Skip to main content

Full text of "Respiratory care : the official journal of the American Association for Respiratory Therapy"

See other formats 


November  1995 
Volume  40,  Number  11 


RESPIRATORS 


A  MONTHLY  SCIENCE  JOURNAL 
40TH  YEAR— ESTABLISHED  1956 


Call  for 

1 996  Open  Forum  Abstracts 

Early  Deadline  February  11,  1996! 


4c 


41st  Annual  Convention  and  Exhibition 

December  2-5 

Orlando,  Florida 


Editorials 

Quiet — Hospital  Zone 
Balancing  the  Risks  &  Benefits 

Noise  Levels  in  the  NICU 

Impact  of  a  Protocol  on  Pulse- 
Oximetry  &  Oxygen  Use 

Update  on  Ventilator-Associated 
Pneumonia 

Nerve  Damage  from  Arterial 
Puncture 

Ventilator  Dyssynchrony  & 
Inadvertent  PEEP 

1995  Open  Forum  Abstracts 


Your  Critical  Skills  Made  The 
Difference,  Tell  Us  How. . . 


u 


Positive  Outcomes  with  Positive  Closure"  Contest 


Share  your  expertise  utilizing  the  "positive  closure"  Passy-Muir  Speaking  Valves  with  your  ventilator 
dependent  patients.  You  could  win  an  opportunity  for  you.  your  patient  and/or  your  department  to  be 
featured  in  a  lull  page  color  advertisement  in  a  national  respiratory  journal,  as  well  as  a  $250  scholarship  to 
the  CEU  program  of  your  choice  and  Passy-Muir  Ventilator  Speaking  Valves  for  your  department  or  facility. 

Positive  Closure  Desi«n 

The  Passy-Muir  Tract  tracheostomiza  pendent  patient 

arc  tin.-  when  the  patient  inh 

no  air  ' 

y,  This  facilitates  improvement  in  management. 

production.  I'  ilumn  of  air  in  the  tracheostomy  tube 

p  the  tube  into 

Rules 

patient. 
mrking  witha  ventilator 


,,//      Xuik 


live  and  would 


Visit  AARC  Booth  1020  in  Orlando      Circle  165  on  reader  service  card 


****... A  Must  See!. ..The  Highlight  of  the  Year! 


ciccr^a.  -frtsdu^ci 


L  OR  =  l  J    rOFtUlvl    iv->!_I>i_L£=ij//i/>i^£;j 


"Extraordinary ! 
Intelligent, 
provocative, 
and  compelling! 
A  timely  event 
that  can  make  a 
difference  in 
your  life." 


A  comprehensive  look  at 

important  case  reports, 

the  latest  methods  and 

device  evaluations,  plus 

current  clinical  studies 

from  around  the  world 

presented  by  members 

of  the  American 

Association  for 

Respiratory  Care 


Featuring: 


Teach  Your  Students  Well! 

Educating  Practitioners,  Patients,  &  Colleagues 

Moderators:  Timothy  Op't  Holt  EdD  RRT 
&  Ralph  E  Battel  MEd  RRT 

Cases,  Series,  &  Clinical  Trials: 
Patients  on  Mechanical  Ventilation 

Moderators:  Robert  L  Chatburn  RRT 
&  Sherry  E  Courtney  MD  MS 

Clinical  Practice  Guidelines  in  Action! 

Moderators:  James  K  Stoller  MD 
&  Lucy  Kester  MBA  RRT 

It's  a  Basic  Black  Dress: 
Something  for  Everyone 

Moderators:  Mark  C  Wilson  MD 
&  John  M  Graybeal  CRTT 

Role  Expansion  &  Work  Redesign: 
Implications  for  the  Profession 

Moderators:  William  Dubbs  MBA  RRT 
&  Richard  M  Ford  BS  RRT  RCP 

Work  &  Weaning  What's  the  Buzz? 
Moderators:  Robert  M  Kacmarek  PhD  RRT 
&  Robert  S  Campbell  RRT 


Benches  to  Trenches: 
Calibration,  Validation,  &  Application 

Moderators:  Charles  G  Durbin  Jr  MD 
&  Thomas  D  East  PhD 

Aerosols — A  Foggy,  Foggy  Dew 

Moderators:  Joseph  L  Rau  Jr  PhD  RRT 
&  Michael  McPeck  BS  RRT 

What  Part  of  NO  Don't  You  Understand? 

Moderators:  Dean  Hess  PhD  RRT 
&  Peter  Betit  BS  RRT 

How  Do  They  Do  What  They  Do? 
Devices  &  Systems 

Moderators:  Jon  Nilsestuen  PhD  RRT 
&  Thomas  A  Barnes  EdD  RRT 

To  Boldly  Go  Where  No  One  Has  Gone  Before: 

TGI  &  PLV 

Moderators:  Mark  Heulitt  MD 
&  David  J  Pierson  MD 

So  You  Think  Money  Grows  on  Trees? 
Containing  the  Costs  of  Care 

Moderators:  Shelley  C  Mishoe  PhD  RRT 
&  Patrick  J  Dunne  MEd  RRT 

Ins,  Outs  &  Subtleties  of  Mechanical  Ventilation 

Moderators:  Richard  D  Branson  RRT 
&  Neil  R  Maclntyre  MD 


Exclusive  Engagement!  Only  at  the  1995  AARC  Convention  in  Orlando,  Florida,  Dec.  2-5! 

Please  arrive  as  early  as  possible  for  best  seats  —  Check  your  program  for  auditoriums  and  presentation  times. 


4£ 


Produced  by  American  Association  for  Respiratory  Care 


G    General  Audiences 


CPT  or  PEP? 

Which  secretion  clearance  therapy  is  best  for  your  patients? 


CPT: 

•  Effective  therapy.  Promotes  secretion  mobilization 
through  postural  drainage,  percussion  or  vibration. 

•  Can  be  difficult  to  tolerate.  May  exacerbate  dyspnea  in 
end-stage  CF  patients',  cause  pain  or  bruising  in  frail  COPD 
or  post-op  patients. 

•  Labor/time  intensive.  Single  CPT  session  can  last  up  to 
one  hour;  COPD  patients  may  require  as  many  as  four 
sessions  daily. 

•  Restrictive.  Requires  a  private  environment,  assistance  of 
second  person,  and  scheduling  around  daily  activities. 

While  CPT  is  an  effective  technique  for  mobilizing 
secretions,  it  can  be  difficult  to  tolerate  for  some 
patients.  That's  why  DHD  developed  TheraPEP"  — 
the  first  system  designed  specifically  for  Positive 
Expiratory  Pressure  (PEP)  therapy. 


Mahlmelftei  Ml,  Fink  JH,  HuftmanCL,  hk-r  II,  "Positive-expiiitoiy  pressure  nasi  thenp) 
Theoretical  and  Pnctiol (  onsJdenttons  ind  i  Review  of  the  I  itenture",  Ropintiwy  Gw,  ll^i 
36:1218-1230 


lll.T.ll'l   I'  1'.  .1   H-, 


PEP: 

•  Effective  therapy.  Employs  positive  expiratory  pressure  to 
improve  clearance  of  secretions  and  facilitate  opening  of  airways. 

•  Easy  to  tolerate.  May  reduce  need  for  postural  drainage. 
Commonly  prescribed  for  post-op  patients. 

•  Cost  efficient.  Can  be  performed  in  less  than  half  the  time 
required  for  conventional  CPT  session,  with  no  decrease  in 
quantity  of  sputum  raised.'  Allows  therapist  to  devote  more  time 
to  other  important  tasks.  Requires  only  one  or  two  initial  patient 
training  sessions. 

•  Helps  patient  maintain  effective 
continuum  of  care  away  from  hospital. 

Convenient,  easy-to-use  TheraPEP  System 
ensures  patients  can  continue  their  therapy 
after  they  depart  for  home. 


3    /A, 


\ 


TheraPEP,  call  DHD 
toll-free  today. 

1-800-847-8000 

Circle  99  on  reader  service  card 
Visit  AARC  Booths  815,  817,  and  819  in  Orlando 


>r 

;sign 

TfiemPEP 


TheraPEP  features  an  integral  Pressure 
Indicator  for  immediate,  visual  feedback;  six  orifice  options  for 
prescribing  the  appropriate  resistance  level;  and  a  versatile  design 
which  permits  use  with  a 
mask  or  mouthpiece.  For 
more  information  on 

Positive  Expiratory  Prrssur?  Tlu'nlfiy  System 

ODHD  _ 

CuiutM  NY  13032  USA  BI9W  !221    RAX  (315)  W7-W83 


RE/PIRATORy  CARE 


A  Monthly  Science  Journal.  Established  1956.  Official  Journal  of  the  American  Association  for  Respiratory  Care 

Contents  ... 


Editor 

Pat  Brougher  BA  RRT 


Associate  Editor 

Kaye  Weber  MS  RRT 

Editorial  Office 

11030  Abies  Lane 
Dallas  TX  75229 
(214)243-2272 

Editorial  Board 

James  K  Stoller  MD,  Chairman 

Cleveland  Clinic  Foundation 

Cleveland,  Ohio 

Richard  D  Branson  RRT 

University  of  Cincinnati 

Medical  Center 

Cincinnati,  Ohio 

Crystal  L  Dunlevy  EdD  RRT 

The  Ohio  State  University 
Columbus,  Ohio 

Charles  G  Durbin  Jr  MD 

The  University  of  Virginia 
Health  Sciences  Center 
Charlottesville,  Virginia 

Thomas  D  East  PhD 

LDS  Hospital 

University  of  Utah 

Salt  Lake  City,  Utah 

Dean  R  Hess  PhD  RRT 

Massachusetts  General  Hospital 
Harvard  Medical  School 
Boston,  Massachusetts 

Neil  R  Maclntyre  Jr  MD 

Duke  University  Medical  Center 

Durham,  North  Carolina 

Shelley  C  Mishoe  PhD  RRT 

Medical  College  of  Georgia 

Augusta,  Georgia 

Joseph  L  Rau  PhD  RRT 

Georgia  State  University 
Atlanta,  Georgia 


November  1995 
Volume  40,  Number  11 


Editorials 

1116      Quiet — Hospital  Zone:  Why  We  Should  Reduce 
Noise  Levels  in  the  Hospital 
fry  Shelley  C  Mishoe — Augusta.  Georgia 

1118      First,  Do  No  Harm — Balancing  the  Risks  and 
Benefits  of  Medical  Procedures 
by  Charles  G  Durbin  Jr — Charlottesville,  Virginia 

Original  Contributions 

1120      Octave  Waveband  Analysis  To  Determine  Sound 

Frequencies  and  Intensities  Produced  by  Nebulizers 
and  Humidifiers  Used  with  Hoods 
by  Shelley  C  Mishoe,  C  Worth  Brooks  Jr,  Franklin  H  Dennison, 
Kim  Valeri  Hill,  and  Thomas  Frye — Augusta,  Georgia  and 
Dayton,  Ohio 

1 125  The  Impact  of  a  Postoperative  Oxygen  Therapy 
Protocol  on  Use  of  Pulse  Oximetry  and  Oxygen 
Therapy 

fry  JJ  Komara  Jr  and  James  K  Stoller — Cleveland,  Ohio 

Reviews,  Overviews,  &  Updates 

1 130      Ventilator-Associated  Pneumonia:  An  Update  for 
Clinicians 

by  Marin  Kollef  and  Patricia  Silver — St  Louis,  Missouri 

Case  Reports 

1141       Median  Nerve  Damage  from  Brachial  Artery 
Puncture:  A  Case  Report 

by  Mary  E  Watson — Boston,  Massachusetts 

1 144      A  Case  of  Patient-Ventilator  Dyssynchrony  Caused 
by  Inadvertent  PEEP 

fry  Tom  Blackson,  Joseph  Ciarlo,  and  Albert  Rizzo — 
Wilmington,  Delaware 

Open  Forum  Abstracts  1995 

1151  Introduction 

1 152  1 995  OPEN  FORUM  Abstracts 
1210      OPEN  FORUM  Author  Index 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1099 


The  old  solutions. 


The 

New 

Solution. 

Bringing  the  Stat  Lab  Bedside™ 


Now  Featuring  Blood  Gas 
and  Electrolyte  Testing 

IRMA®,  the  truly  portable  bedside  analyzer, 

solves  your  need  for  critical  blood  analysis 

with  immediate  turn-around. 

•  As  accurate  as  a  benchtop  analyzer 

•  Single-use  cartridge  means 
a  predictable  cost  per  test 

•  One-step  blood  handling  plus 
closed  system  for  safety 

•  Auto  calibration  before  each  test 
assures  accurate  results 

•  Designed  to  meet  CLIA  requirements 

IRMA  features  data  management  and 
downloading  capabilities  with  complete 
QC  menu,  QC  lockout  and  secured 
user  ID  function. 

Discover  the  new  solution  in 
STAT  testing...  IRMA. 

Call  1-800-949-4762 
Department  RC. 


Managing  Editor 

Ray  Masferrer  BA  RRT 

Assistant  Editor 

Kris  Williams  BA 

Editorial  Assistant 

Linda  Barcus  BBA 

Section  Editors 

Robert  R  Fluck  Jr  MS  RRT 
MS  Jastremski  MD 
Blood  Gas  Corner 

Hugh  S  Mathewson  MD 
Drug  Capsule 

Richard  D  Branson  RRT 

Robert  S  Campbell  RRT 

Kittredge  's  Corner 

Charles  G  Irvin  PhD 

Jack  Wanger  MBA  RPFT  RRT 

PFT  Corner 

Patricia  Ann  Doorley  MS  RRT 
Charles  G  Durbin  Jr  MD 
Test  Your  Radiologic  Skill 

Consulting  Editors 

Frank  E  Biondo  BS  RRT 

Howard  J  Birenbaum  MD 

Robert  L  Chatbum  RRT 

Donald  R  Elton  MD 

Ronald  B  George  MD 

James  M  Hurst  MD 

Robert  M  Kacmarek  PhD  RRT 

Michael  McPeck  BS  RRT 

David  J  Pierson  MD 

John  Shigeoka  MD 

Jeffrey  J  Ward  MEd  RRT 

Production 

Steve  Bowden 

Gary  Caywood 

Donna  Knauf 

Karen  Singleterry 

Marketing 

Director 
Dale  Griffiths 

Advertising  Assistant 
Beth  Binkley 

Advertising 

Williams  &  Wilkins 


...  Contents 


November  1995 
Volume  40,  Number  11 


Books,  Films,  Tapes,  &  Software 

1 148  Principles  and  Applications  of  Cardiorespiratory 
Care  Equipment 

reviewed  by  Fran  Pieilahte — Denver,  Colorado 

Letters 

1149  Bad  Press  for  RCPs? 

by  Robert  R  Fluck  Jr — Syracuse,  New  York 

1 149      Therapeutic  Touch  and  Respiratory  Therapy 
by  Stephanie  Haines — Areata.  California 

AARC  Convention  Exhibitors 

1218      Convention  Exhibitors 

In  This  Issue 

1 102  Abstracts  from  Other  Journals 

1240  Advertisers  Index  and  Help  Lines 

1240  Author  Index 

1 230  Calendar  of  Events 

1 223  Call  for  Open  FORUM  Abstracts 

1226  New  Products  &  Services 

1222  Notices 


j! 


RESPIRATORY  Care  (ISSN  0020-1324)  is  published  monthly  by  Daedalus  Enterprises  Inc.  at  1 1030  Abies  Lane. 
Dallas  TX  75229-4593.  for  the  American  Association  for  Respiratory  Care.  One  volume  is  published  per  year  beginning 
each  January.  Subscription  rates  are  $65  per  year  in  the  US;  $80  in  all  other  countries  (for  airmail,  add  $84). 
The  contents  of  the  Journal  are  indexed  in  Hospital  and  Health  Administration  Index,  Cumulative  Index  to 
Nursing  and  Allied  Health  Literature,  and  Excerpta  Medica.  Abridged  versions  of  RESPIRATORY  CARE  are  also 
published  in  Italian  and  Japanese,  with  permission  from  Daedalus  Enterprises  Inc. 

Second  class  postage  paid  at  Dallas  TX.  POSTMASTER:  Send  address  changes  to  RESPIRATORY  CARE,  Mem- 
bership Office.  Daedalus  Enterprises  Inc.  1 1030  Abies  Lane,  Dallas  TX  75229-4593. 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1101 


Abstracts 


Editorials,  Commentaries,  and  Reviews  To  Note 

Long-Term  Oxygen  Therapy  (Review)— SP  Tarpy.  BR  Celli.  N  Engl  J  Med  1995;333(  1 1 ): 
710-714. 

Guidelines  for  Pediatric  Emergency  Care  Facilities — American  Academy  of  Pediatrics 
Committee  on  Pediatric  Emergency  Medicine.  Pediatrics  1995;96(3):526-537. 


Neonatal  Predictors  of  Infection  Status  and 
Early  Death  among  332  Infants  at  Risk  of  HTV- 
1  Infection  Monitored  Prospectively  from 
Birth — EJ  Abrams.  PB  Matheson.  PA  Thomas. 
DM  Thea.  K  Krasinski.  G  Lambert.  N  Shaffer. 
M  Bamji.  D  Hutson,  K  Grimm,  A  Kaul,  D  Bate- 
man,  M  Rogers,  the  New  York  City  Perinatal  HIV 
Transmission  Collaborative  Study  Group.  Pedi- 
atrics 1995;96(3):451. 

BACKGROUND  &  METHODS:  Differences  in 
newborn  outcome  measures  for  human  immun- 
odeficiency virus  ( HIV  )-l -infected  and  HIV-1- 
exposed  but  uninfected  infants  have  been  found 
in  several  studies,  but  not  in  others.  Eighty-four 
infected  and  248  uninfected  children  born  to  HIV- 
1 -seropositive  mothers  followed  prospectively 
in  a  multicenter.  perinatal  HIV- 1  transmission  co- 
hort study  were  compared  for  differences  in  ma- 
ternal demographics,  health  status,  and  newborn 
outcome  measures,  including  delivery  compli- 
cations, physical  examination  findings,  neona- 
tal complications,  and  laboratory  results.  RE- 
SULTS: Mothers  of  HIV- 1 -infected  infants  were 
more  likely  than  those  of  uninfected  infants  to 
have  acquired  immunodeficiency  syndrome 
(AIDS)  diagnosed  through  2  weeks  postpartum 
(21%  vs  11%,  p  =  0.04);  the  transmission  rate  for 
the  38  women  with  AIDS  was  37%  compared 
with  22%  for  the  245  women  without  AIDS.  Two 
of  27  (7%)  women  receiving  zidovudine  during 
pregnancy  had  infected  infants  compared  with 
73  (27%)  of  275  women  who  did  not  receive  zi- 
dovudine (p  =  0.033).  Mean  gestational  age  was 
significantly  lower  among  HI V-l -infected  (37 
weeks)  than  among  uninfected  infants  (38  weeks; 
p  <  ().(X)1 ).  Infected  infants  had  significantly  high- 
er rates  of  prematurity  (gestational  age  <  37 
weeks)  (3391  VS  19%,  p  =  0.01)  and  extreme  pre- 
maturity (gestational  age  <  34  weeks)  (18%  vs 
W/i ,  p  =  0.001 1  than  uninfected  infants.  Infection 
was  associated  with  lower  birthweighl  (2,533  g 
vs  2.862  g,  p  <  0.001)  and  smaller  head  cir- 


cumference (32.0  cm  vs  33.1  cm,  p  =  0.001).  HJV- 
1 -infected  infants  were  significantly  more  like- 
ly to  be  small  for  gestational  age  (26%  vs  16%. 
p  =  0.04)  and  low  birthweight  «  2,500  g)  (45% 
vs  29%,  p  =  0.006)  than  infants  who  were  un- 
infected. Twenty-two  (26%)  HIV- 1 -infected  chil- 
dren died  during  a  median  follow-up  of  27.6 
months  (range  1.9  to  98.3  months).  Prematuri- 
ty was  predictive  of  survival:  by  Kaplan-Meier, 
an  estimated  55%  (95%  confidence  interval,  3 1  % 
to  72%)  of  preterm  infected  children  survived  to 
24  months  compared  with  84%  (95%  confidence 
interval,  70%  to  92%)  of  full-term  infected  chil- 
dren (p  =  0.005).  CONCLUSION:  Infants  born 
to  women  with  AIDS  are  at  higher  risk  for  H1V- 
1  infection  than  are  infants  born  to  HIV- 1 -infected 
women  with  AIDS  not  yet  diagnosed.  Women 
receiving  zidovudine  appear  less  likely  to  trans- 
mit HI  V- 1  to  their  infants.  Significantly  higher 
rates  of  prematurity  and  intrauterine  growth  re- 
tardation were  found  among  HIV- 1 -infected  in- 
fants than  among  those  in  the  uninfected,  HIV- 
1 -exposed  control  group.  Prematurity  was 
associated  with  shortened  survival  in  HIV- 1 -in- 
fected infants.  Measures  of  intrauterine  growth 
and  gestation  appear  to  be  important  predictors 
of  HI  V-l  infection  status  for  seropositive  infants 
and  of  prognosis  for  the  infected  infant. 

Epiglottitis  and  Haemophilus  influenzae  Im- 
munization: The  Pittsburgh  Experience — A 
Five- Year  Review — HG  Valdepena,  ER  Wald, 
E  Rose.  K  Ungkanont.  ML  Casselbrant.  Pediatrics 
1995;96(3):424. 

OB1ECTIVE:  Current  trends  in  the  clinical  pre- 
sentation and  management  of  children  with 
epiglottitis  at  Children's  Hospital  of  Pittsburgh 
were  reviewed  for  the  years  1988  to  1993. 
METHODOLOGY:  The  medical  records  of  all 
patients  diagnosed  as  having  epiglottitis  between 
July  1988  and  June  1993  at  the  Children's  Hos- 
pital of  Pittsburgh  were  reviewed.  An  addition- 


al telephone  survey  was  conducted  among  the  pri- 
mary care  physicians  of  those  patients  to  collect 
information  regarding  administration  of  Haemo- 
philus influenzae  type  b  (HIB)  vaccines.  RE- 
SULTS: During  the  study  period  28  children  (age 
range,  1 1  months  to  1 1  years.  10  months)  were 
admitted  with  the  diagnosis  of  epiglottitis.  Cases 
declined  remarkably  in  1991.  Fever,  sore  throat, 
and  stridor  were  the  usual  symptoms.  HIB  was 
the  most  common  cause  of  epiglottitis  accounting 
for  2 1  cases.  Candida  albicans  was  recovered 
from  the  surface  culture  of  the  epiglottis  in  2  pa- 
tients. At  least  1 1  children  experienced  vaccine 
failure:  9  with  polysaccharide  vaccine  and  2  with 
the  conjugate  vaccine  for  HIB.  CONCLUSION: 
Cases  of  epiglottitis  have  declined  dramatical- 
ly since  licensure  of  HIB  conjugate  vaccines  for 
use  in  early  infancy.  At  least  52%  of  the  reported 
cases  represent  vaccine  failures  with  the  purified 
polysaccharide  vaccine. 

Incentive  Spirometry  To  Prevent  Acute  Pul- 
monary Complications  in  Sickle  Cell  Diseases — 

PS  Bellet.  KA  Kalinyak,  R  Shukla,  MJ  Gelfand, 
DL  Rucknagel.  N  Engl  J  Med  1995;333(  1 1  ):699. 

BACKGROUND:  This  study  was  designed  to  de- 
termine the  incidence  of  thoracic  bone  infarction 
in  patients  with  sickle  cell  diseases  who  were  hos- 
pitalized with  acute  chest  or  back  pain  above  the 
diaphragm  and  to  test  the  hypothesis  that  incentive 
spirometry  can  decrease  the  incidence  of  at- 
electasis and  pulmonary  infiltrates.  METHODS: 
We  conducted  a  prospective,  randomized  trial  in 
29  patients  between  8  and  21  years  of  age  with 
sickle  cell  diseases  who  had  38  episodes  of  acute 
chest  or  back  pain  above  the  diaphragm  and  were 
hospitalized.  Each  episode  of  pain  was  consid- 
ered to  be  an  independent  event.  At  each  hospitali- 
zation, patients  with  normal  or  unchanged  chest 
radiographs  on  admission  were  randomly  assigned 
lo  treatment  with  spirometry  or  to  a  control  non- 
spirometry  group.  Each  patient  in  the  spirome- 


102 


RESPIRATORY  CARE  •  NOVEMBER  'c)5  VOL  40  NO 


Always 

A  Step  Ahead! 

Evita  makes  work  of  breathing 
even  easier! 


0.5  t(s) 


Occlusion-pressure 


I  P    i 

:     20  : 

I  0  =i 

i   -10  1 


Intrinsic  PEEP 


Now  Drager  provides  you  with  two  more 
powerful  tools  to  optimize  weaning  of  your 
patients. 

Introducing  Flowtrigger  without  increase  of 
expiratory  resistance,  combined  with  P01 
measurement  to  determine  the  patients 
ventilatory  drive. 

To  extend  monitoring  capabilities  Evita  now 
includes  the  ability  to  measure  Intrinsic 
Peep  with  the  display  of  Trapped  Volume. 

With  Drager  you  can  stay  one  step  ahead  in 
providing  safe,  patient  friendly  ventilation. 
For  the  difference  your  patients  can  feel, 
choose... 

Drager:  Technology  for  Life 


Drager 

Technology  for  life 

4101  Pleasant  Valley  Road     Suite  100     Chantilly,  VA  22021 
Tel  (703)  817-01 00     Fax  (703)  817-0101 


Circle  101  on  reader  service  card 
Visit  AARC  Booth  526  in  Orlando 


Abstracts 


1 1  >  group  took  10  maximal  inspirations  using  an 
incentive  spirometer  every  2  hours  between  8  am 
and  10  PM  and  while  awake  during  the  night,  until 
the  ehest  pain  subsided.  A  seeond  radiograph  was 
obtained  3  or  more  days  after  admission,  or  soon- 
er if  clinically  necessary,  to  determine  the  inci- 
dence of  pulmonary  complications.  Bone  scan- 
ning was  performed  no  sooner  than  2  days  after 
hospital  admission  to  determine  the  incidence  of 
thoracic  bone  infarction.  RESULTS:  The  inci- 
dence of  thoracic  bone  infarction  was  39.5%  ( 15 
of  38  hospitalizations).  Pulmonary  complications 
(atelectasis  or  infiltrates)  developed  during  only 
1  of  1 9  hospitalizations  of  patients  assigned  to  the 
spirometry  group,  as  compared  with  8  of  19 
hospitalizations  of  patients  in  the  nonspirometry 
group  (p  =  0.019).  Among  patients  with  thoracic- 
bone  infarction,  no  pulmonary  complications  de- 
veloped in  those  assigned  to  the  spirometry  group 
during  a  total  of  7  hospitalizations,  whereas  they 
developed  during  5  of  8  hospitalizations  in  the 
nonspirometry  group  (p  =  0.025).  CONCLU- 
SIONS: Thoracic  bone  infarction  is  common  in 
patients  with  sickle  cell  diseases  who  are  hospi- 
talized with  acute  chest  pain.  Incentive  spirom- 
etry can  prevent  the  pulmonary  complications  (at- 
electasis and  infiltrates)  associated  with  the  acute 
chest  syndrome  in  patients  with  sickle  cell  dis- 
eases who  are  hospitalized  with  chest  or  back  pain 
above  the  diaphragm. 

Outcome  of  Infants  Weighing  Less  Than  800 
Grams  at  Birth:  15  Years'  Experience — TR  La 
Pine.  JC  Jackson.  FC  Bennett.  Pediatrics  1995:96 
(3):479. 

OBJECTIVE:  Mortality  and  neurodevelopmen- 
tal  morbidity  among  infants  weighing  <  800  g  at 
birth  are  compared  in  3  separate  studies  from  the 
same  intensive  care  nursery  during  an  almost  15- 
year  period.  METHODS:  The  survival  and  neuro- 
developmental  outcome  of  210  infants  with  birth- 
weights  <  800  g  admitted  to  the  University  of 
Washington  neonatal  intensive  care  unit  between 
1 986  and  1 990  are  compared  w  ith  those  of  2  pre- 
vious cohorts  (1977  through  1980  and  1983 
Ihrough  1985)  of  extremely  low  birthweight 
(ELBW)  infants  from  the  same  nursery.  RE- 
SULTS. Annual  admissions  of  these  ELBW  in- 
fants nearly  doubled  from  1977  to  1990.  where- 
as nursery  survival  rose  from  20%  between  1977 
and  1 980,  to  36%  between  1 983  and  1 985.  to  49% 
in  this  current  sludy  of  births  between  1 986  and 
1990.  The  greatest  increase  in  survival  among  the 
3  studies  occurred  among  infants  with  hirthweights 
<  7(H)  g.  Female  survival  was  209S  higher  than 
male  survival  in  each  of  the  time  periods.  The 
prevalence  of  major  neurosensory  impairments 
did  not  differ  significantly  among  the  3  Study 
groups  (19%, 21%,  and  22'  i  respective!)  I;  male 
survivors  were  more  commonly  affected  across 
time  periods.  There  were  no  differences  in  mean 
cognitive  lesl  scores  between  the  current  1986 
through  1990  birth  cohort  (94)  and  the  2  previ- 


ous cohorts  (1977  through  1980, 98:  1983  through 
1985,  89).  CONCLUSIONS:  The  experience  of 
our  center  with  these  ELBW  infants  over  time 
seems  reassuring  to  the  extent  that  progressive  in- 
creases in  nursery  survival  have  not  resulted  in  in- 
creased neurodevelopmental  morbidity. 

Persistent  Pulmonary  Hypertension  of  the  New- 
born Treated  with  Magnesium  Sulfate  in  Pre- 
mature Neonates — TJ  Wu.  RJ  Teng.  KT  Yau. 
Pediatrics  1995:96(31:472. 

OBJECTIVE:  To  evaluate  the  clinical  effects  of 
magnesium  sulfate  (MgSO.0  in  the  treatment  of 
persistent  pulmonary  hypertension  of  the  new- 
bom  (PPHN)  in  premature  infants.  METHODS: 
This  was  a  prospective,  nonrandomized,  clinical 
study.  Seven  premature  neonates  with  PPHN  were 
treated  with  MgSOj  as  soon  as  documentation 
of  an  interatrial  right-to-left  shunt  was  made.  A 
loading  dose  of  200  mg/kg  was  infused  over  30 
minutes,  followed  by  a  maintenance  dose  of  20- 
50  mg/kg/h.  Alveolar-arterial  oxygen  tension  dif- 
ference ( AaDO:)  and  oxygenation  index  were  fol- 
lowed up  sequentially  as  the  primary  outcome 
measures.  Blood  pressures  and  serum  electrolytes 
were  also  monitored.  RESULTS:  Six  cases  re- 
sponded clinically.  The  decrease  of  AaDO; 
reached  significance  at  36  hours,  but  the  decrease 
of  oxygenation  index  was  not  significant  over  72 
hours.  Four  infants  survived.  No  significant  side 
effects  were  encountered.  CONCLUSION:  Our 
results  suggest  that  MgSOj  may  be  considered 
as  an  alternative  treatment  of  PPHN  in  prema- 
ture infants. 

School-Based  Screening  for  Tuberculous  In- 
fection: A  Cost-Benefit  Analysis — JC  Mohle- 
Boetani.  B  Miller.  M  Halpem.  A  Trivedi.  J  Lessler. 
SL  Solomon,  M  Fenstersheib.  JAMA  1995:274 
(8):613. 

OBJECTIVE:  To  compare  tuberculin  screening 
of  all  kindergartners  and  high  school  entrants 
(screen-all  strategy)  vs  screening  limited  to  high- 
risk  children  (targeted  screening).  DESIGN:  De- 
cision, cost-effectiveness,  and  cost-benefit  analy- 
ses. SETTING  AND  SUBJECTS:  Students  in  a 
large  urban  and  rural  county.  DEFINITIONS:  High 
risk  of  tuberculous  infection  was  defined  as  birth 
in  a  country  with  a  high  prevalence  of  tubercu- 
losis. Low  risk  was  defined  as  birth  in  the  Unit- 
ed States.  OUTCOME  MEASURES:  Tubercu- 
losis cases  prevented  per  I O.(XK)  children  screened. 
Net  costs,  net  cost  per  case  prevented,  benefit-cost 
ratio,  and  incremental  cost-effectiveness.  RE- 
SULTS: The  screen-all  strategy,  would  prevent 
14.9  cases  per  1 0,000  children  screened:  target 
ed  screening  would  prevent  84.9  cases  per  10,000 
children  screened.  The  screen-all  strategy  is  more 
costly  than  no  screening;  the  benefit-cost  ratio  is 
0.58.  Targeted  screening  would  result  m  a  net  sav 

ings;  the  benefit-COSt  ratio  is  1 .2.  Screening  all  chil 
drcn  is  cost  saving  only  if  the  reactor  rale  is  20' . 


or  greater.  The  cost  per  additional  case  prevent- 
ed for  screening  all  children  compared  w  ith  tar- 
geted screening  ($34,666)  is  more  than  twice  as 
high  as  treatment  and  contact  tracing  for  a  case 
of  tuberculosis  ($16,392).  CONCLUSIONS:  Tar- 
geted screening  of  schoolchildren  is  much  less 
costly  than  mass  screening  and  is  more  efficient 
in  prevention  of  tuberculosis. 

Prehospital  Management  of  Pediatric  Asthma 
Requiring  Hospitalization — JD  Fisher.  RJ  Vinci. 
Pediatr  Emerg  Care  1995;11(4):217. 

Our  objective  was  to  evaluate  the  quality  of  pre- 
hospital assessment  and  management  in  pediatric 
asthma  requiring  hospitalization  via  a  retrospective 
chart  review.  Charts  were  obtained  from  a  pedi- 
atric emergency  department  (ED)  w  ith  24.000  an- 
nual visits.  Included  in  the  study  were  27  patients 
<  18  years  of  age  with  asthma  requiring  hospital- 
ization, transported  to  the  Boston  City  Hospital 
Pediatric  ED  by  Boston  Emergency  Medicine  Ser- 
vices (EMS).  We  found  that  12  patients  admit- 
ted to  the  pediatric  intensive  care  unit  over  an  1 8- 
nionth  period,  and  15  patients  admitted  to  the  ward 
over  a  6-month  period,  received  prehospital  care 
from  Boston  EMS.  Only  63%  of  cases  (17/27)  had 
a  physical  examination  marker  of  asthma  sever- 
ity noted  on  the  EMS  record.  Twenty-six  percent 
of  cases  17/27)  did  not  receive  O:  in  the  field.  Thir- 
ty percent  of  eases  (8/27)  were  hypoxic  at  ED  pre- 
sentation. None  of  the  hypoxic  patients  had  re- 
ceived albuterol  in  the  field,  and  1  did  not  receive 
Oi.  We  conclude  that  further  study  of  the  pre- 
hospital assessment  and  management  of  pediatric 
asthma  is  warranted. 

Children  with  Asthma  in  the  Emergency  De- 
partment: Spectrum  of  Disease,  Variation  with 
Ethnicity,  and   Approach   to  Treatment — 

I  Horowitz.  B  Wolach.  A  Eliakim.  I  Berger. 
S  Gilboa.  Pediatr  Emerg  Care  1995:11(4)240. 

The  role  of  the  pediatric  emergency  department 
(ED)  in  the  management  of  acute  asthma  was  as- 
sessed by  examining  patterns  of  referrals,  ad- 
missions, clinical  patient  evaluation,  laboratory 
tesis  ordered,  and  treatment  instituted.  The  func- 
tioning of  the  attending  physicians  with  different 
degrees  of  seniority  was  also  evaluated.  One  thou- 
sand thirty-six  children  with  acute  asthma  (5  3'  I 
of  all  v  isits )  were  admitted  to  the  ED  during  1 1>'>( ). 
The  mean  age  w  as  5.5  years,  and  the  male  to  fe- 
male ratio  was  2.6: 1 .  Fifty  percent  of  the  patients 
reported  atopic  disease  in  their  immediate  fam- 
ily, and  upper  respiratory  tract  infection  preceding 
the  atlaek  was  reported  in  27',  of  patients.  Sig- 
nificant differences  were  observed  between  Arab 
and  Jew  ish  patients:  more  Arab  patients  presented 
alter  physician  referral  (90  VS  33%),  in  morning 
hours  (43  VS  2o\  ).  and  altera  longer  duration  of 
\v  mptoms.  Experienced  physicians  ordered  fewer 
laboratory  icsis  and  treated  the  patients  less  ag- 
gressively than  junior  physicians.  Patients  treat- 


104 


Respirators  Care •  November '95 voi  -kino  11 


If  Intubating  Him 
Raises  Big  Concerns... 


Here's  A  Small  Suggestion. 


Introducing  the  Pedi-Cap1" 
Pediatric  End-Tidal  C02  Detector. 

The  technology  of  Easy  Cap®  now 
available  in  a  size  suitable  for  NICU, 
PICU,  and  pediatric  EMS  patients!" 

Proven  colorimetric  technology  for  objective 
verification  of  correct  endotracheal  tube  placement. 

A  nontoxic  chemical 


As  an  adjunct  to  current  practices,  Pedi-Cap 
provides  a  simple,  cost-effective  approach  to 
documenting  ET  tube  position  during  emergency 
intubations  and  in  the  NICU  and  PICU.  So 
with  Pedi-Cap  and  Easy  Cap,  you  can  now 


indicator  quickly 

responds  to  exhaled 

C02  with  a  simple 

color  change  from 

purple  to  yellow. 
Circle  102  on  reader  service  card 

Visit  AARC  Booths  802, 1302, 1303  and  1305  in  Orlando 

edi-Cap  is  recommended  for  use  on  patients  weighing  1-15  kg.  Easy  Cap  and  Pedi-Cap  an 


INSPIRATION  EXPIRATION 

Easy  Cap  (pictured)  ami  Pedi-Cap 
attach  to  the  endotracheal  tube  to 
detect  FTCO2  levels  with  breath-to- 
breath  response. 


]  ACTUAL    SIZE 

standardize  patient  protocols  regardless  of  patient  size 

Isn't  it  time  you  started  using  Pedi-Cap? 

For  more  information  on  Pedi-Cap  and  our  complete 
family  of  etCOz  detection  and  monitoring  products, 
contact  your  Nellcor  Puritan  Bennett  representative 
or  call  1-800-NELLCOR  or  510-463-4000. 


NELLCOR 
PURITAN 
BENNETT. 

:rademarks  of  Nellcor  Puritan  Bennett  Inc.  ©  1995  Nellcor  Puritan  Bennett  Inc.  All  rights  reserved. 


Abstracts 


ed  hy  senior  physicians  slaved  less  time  in  the  ED, 
and  a  smaller  proportion  of  patients  was  hospi- 
talized  (4  \s  I99J  i  Patients  admitted  by  senior 
physicians  had  a  longer  period  of  hospitalization 
(4.7  vs  1.2  days).  This  study  shows  that  ethnic- 
ity influenced  the  pattern  of  utilization  of  the  ED 
and  that  the  approach  to  care  differed  among  ju- 
nior and  senior  physicians. 

In-Hospital  Mortality  after  Out-of-Hospital 
Cardiac  Arrest— NR  Grubb.  RA  Elton,  KAA 
Fox.  Lancet  1995:346:417. 

In-hospital  management  of  out-of-hospital  car- 
diac arrest  is  complicated  by  uncertainty  about 
prognosis  and  the  need  to  identify  markers  of  ad- 
verse outcome  in  individuals  surviving  initial  re- 
suscitation. We  sought  to  identify  factors  that  pre- 
dict in-hospital  death  among  patients  who  initially 
survive  out-of-hospital  cardiac  arrest.  We  investi- 
gated 346  consecutive  cases  of  out-of-hospital  car- 
diac arrest  received  by  a  single  centre  in  Edinburgh. 
UK  (270  cases  examined  retrospectively,  76 
prospectively  ).  Of  the  retrospective  cohort.  246 
cases  were  thought  to  be  of  cardiac  origin.  There 
were  associations  between  in-hospital  mortality 
and  pre-arrest  variables,  resuscitation  variables, 
and  factors  measured  during  admission.  Crew-wit- 
nessed arrests  were  associated  with  low  mortal- 
ity: arrest  rhythm  (p  <  0.001 ),  resuscitation  by  a 
health  professional  (p  <  0.05),  conscious  level  on 
admission  (p  <  0.001 ),  and  requirement  for  ven- 
tilaton  (p  <  0.05)  independently  predicted  in-hos- 
pital mortality.  A  weighted  prognostic  scoring  sys- 
tem based  on  3  of  these  variables  accurately 
predicted  the  likelihood  of  in-hospital  death  in  the 
prospective  test  group.  Further  assessment  of  con- 
scious level  during  admission  with  the  Glasgow 
coma  score  predicted  mortality  rates  in  the  study 
population,  but  coma  did  not  predict  a  hopeless 
prognosis  in  individual  cases  unless  it  persisted 
for  72  hours  or  more.  Accurate  prognostic  as- 
sessment of  out-of-hospital  cardiac  arrest  surviv- 
ors can  be  made  from  information  available  on 
admission.  Of  factors  that  independently  predicted 
outcome,  the  skill  of  the  resuscitator  is  most  read- 
ily modified.  This  suggests  that  public  training 
in  resuscitation  may  reduce  mortality  rates. 

Efficacy  of  Expiratory  Tracheal  Gas  Insuf- 
flation in  a  Canine  Model  of  Lung  Injury — 

A  Nahum,  RS  Shapiro,  SA  Ravenscraft, 
AB  Adams,  JJ  Marini.  Am  J  Respir  Crit  Care  Med 
1995:152:4X9 

Tracheal  gas  insufflation  (TGI)  improves  the  ef- 
ficiency of  CO.  elimination  hy  reducing  (he  COi- 
laden  dead  space  oi  the  airways.  Trie  effect  of  TGI 
on  I'.,,  i,  diminishes  in  the  setting  of  acme  lung 
injury  (Al.li  because  an  increased  alveolar  com- 
ponent dominates  the  total  physiologic  dead  space. 
Nevertheless,  adopting  a  strategy  of  permissive 

hypercapnia  should  partially  ollset  (he  decreased 
efficac)  ol  TOl  by  increasing  CO2  concentration 


in  the  proximal  airways.  To  examine  these  issues 
we  studied  the  CO;  removal  efficacy  of  expira- 
tory TGI  as  an  adjunct  to  conventional  mechanical 
ventilation  (CMV)  before  and  after  oleic  acid- 
induced  lung  injury  (OAI).  We  first  examined  the 
effect  of  TGI  before  and  after  OAI.  keeping  tidal 
volume  (VT)  and  frequency  constant,  and  allowing 
PaCO:  to  increase  after  OAI.  We  then  tested  TGI 
efficiency  after  matching  Paco;  after  OAI  to  its 
pre-OAI  level  by  increasing  VT  (post-OA/Vj 
stage ).  Paco:  was  53  ±  3,  79  ±  2 1 ,  and  52  ±  4  mm 
Hg  in  the  pre-OAI,  post-OAI.  and  post-OA/VT 
stages  of  CMV,  respectively.  The  corresponding 
decrements  in  Paco:  produced  by  TGI  at  a  flow 
rate  of  10  L/min  were  16  ±  3,  24  ±  10,  and  10  ± 
2  mm  Hg,  respectively.  TGI  decreased  total  phys- 
iologic dead  space  per  breath  ( Vrj)  by  56.  3 1 ,  and 
28  mL  during  the  pre-OAI,  post-OAI,  and  post- 
OA/VT  stages,  respectively.  Despite  a  smaller  re- 
duction in  Vd  during  the  post-OAI  stage,  the  ef- 
fect of  TGI  on  Paco:  was  preserved  because  of 
the  relatively  high  P.,co:  prior  to  its  initiation.  For 
a  similar  decrement  in  VD  during  the  post-OA/Vj 
stage,  TGI  was  less  effective  in  decreasing  Paco 
Our  results  can  be  explained  by  the  inverse  re- 
lationship between  Paco:  and  the  physiologic 
dead-space  fraction  (VD/Vj).  in  which  at  high 
Vn/Vj  a  small  decrement  in  Vrj  causes  a  relatively 
large  decrease  in  Paco2-  We  conclude  that  ap- 
plication of  a  permissive  hypercapnia  strategy  dur- 
ing ALI  counterbalances  the  decreased  CO2  re- 
moval efficacy  of  TGI  caused  by  increased 
alveolar  dead  space. 

Effects  of  PEEP  on  Liver  Arterial  and  Venous 
Blood  Flows — N  Brienza.  JP  Revelly,  T  Ayuse, 
IL  Robotham.  Am  J  Respir  Crit  Care  Med  1995; 

152:504. 

Total  venous  return  decreases  with  positive  end- 
expiratory  pressure  (PEEP).  It  is  likely  that  the 
liver  plays  an  important  role  in  this  response,  ei- 
ther through  the  development  of  an  increase  in  ve- 
nous resistance  or  through  an  increase  in  the  ve- 
nous backpressure  at  the  outflow  end  of  the  liver. 
In  addition,  hepatic  arterial  flow  is  reported  to  be 
selectively  decreased  by  the  application  of  PEEP. 
Therefore,  to  clarify  the  effects  of  PEEP  on  liver 
hemodynamics,  we  generated  pressure-flow  (P-Q) 
relationships  in  both  liver  vascular  beds  of  anes- 
thetized, mechanically  ventilated  pigs  at  PEEP  of 
0,5,  10,  and  15  cm  H;0  to  obtain  values  of  back- 
pressure (Pback,  mm  Hg)  from  linear  extrapolation 
of  the  P-Q  relationships  and  resistance  (mm 
Hg/mL/min/kg)  from  its  slope.  PEEP  decreased 
portal  vein  flow  (Qpv )  and  caused  an  increase  in 
the  liver  venous  resistance  (from  0.08  ±  0.01  to 
0.16  ±  0.02  mm  Hg/mL/min/kg;  p  <  0.05). 
Ppvback  and  right  atrial  pressure  (Pra)  increased 
equally  (from  5. 1  ±  0.3  to  9.9  ± 0.4  mm  Hg,  p  < 
0.05,  and  from  4.0  ±  0.2  to  8.6  ±  0.5  mm  Hg,  p  < 
0.05.  respectively,  at  PEEP  15).  The  reduction  in 
portal  venous  flow  was  related  to  an  increase  in 
the  backpressure  to  flow  (as  a  result  of  an  increase 


in  Pra)  and  to  an  increase  in  liver  venous  resis- 
tances that  may  cause  blood  pooling  in  the  splanch- 
nic compartment  and  decrease  venous  return 
through  the  liver.  PEEP  increased  Phaback  (from 
11.2  ±0.9  to  14.5  ±0.7  mm  Hg  at  PEEP  15,  p< 
0.05 )  but  did  not  change  hepatic  arterial  resistance. 
Because  a  decrease  in  Qpv.  without  PEEP,  de- 
creases hepatic  arterial  resistance  via  the  hepat- 
ic artery  buffer  response,  opposing  constricting 
and  dilating  effects  appear  to  occur  with  the  ap- 
plication of  PEEP. 

Should  Mechanical  Ventilation  Be  Opti- 
mized to  Blood  Gases,  Lung  Mechanics,  or 
Thoracic  CT  Scan? — F  Brunet,  D  Jeanbour- 
quin,  M  Monchi.  JP  Mira,  L  Fierobe,  A  Ar- 
maganidis.  B  Renaud.  M  Belghith,  S  Nouira. 
JF  Dhainaut,  J  Dall'ava-Santucci.  Am  J  Respir 
Crit  Care  Med  1995:152:524. 

This  study  was  aimed  at  providing  data  for  opti- 
mization of  mechanical  ventilation  in  patients  with 
acute  respiratory  distress  syndrome  ( ARDS).  The 
effects  of  ventilation  with  positive  end-expiratory 
pressure  (PEEP)  titrated  to  blood  gases  were  stud- 
ied by  thoracic  computed  tomographic  (CT)  scans 
and  lung  mechanics  measurements  in  8  patients. 
CT  density  histograms  at  end  expiration  were  used 
to  investigate  the  effects  of  PEEP  on  3  differently 
aerated  zones.  Static  pressure-volume  (P-V)  curves 
were  used  to  determine  the  deflection  point  above 
which  baro-volotrauma  (a  combination  of  baro- 
trauma and  volotrauma)  may  occur.  Peak  pres- 
sures, plateau  pressures,  and  lung  volumes  mea- 
sured by  Respitrace-  were  compared  with  the 
deflection  point.  CT  scan  showed  that  PEEP  in- 
creased "normally  aerated"  areas,  decreased  "non- 
aerated"  areas,  and  did  not  change  "poorly  aer- 
ated" zones.  No  correlations  were  found  between 
CT  scan  and  either  Pao:  or  mechanical  data.  Pres- 
sure at  the  deflection  point  was  lower  than  the  usu- 
ally recommended  35  to  40  cm  H<)  for  peak  pres- 
sure in  4  patients  (range.  28  to  32  cm  H^O).  With 
regard  to  plateau  pressures,  only  1  patient  was  ven- 
tilated above  the  deflection  point.  However,  mon- 
itoring of  volumes  showed  that  these  4  patients 
had  an  end-inspiratory  volume  above  this  point. 
We  conclude  that  mechanical  ventilation  may  be 
initially  adjusted  on  the  basis  of  blood  gas  val- 
ues and  then  optimized  on  the  basis  of  lung  me- 
chanics to  limit  the  risk  of  baro-volotrauma. 

Alterations  of  Lung  and  Chest  Wall  Mechanics 
in  Patients  with  Acute  Lung  Injury:  Effects  of 
Positive  End-Expiratory  Pressure — P  Pelosi. 
M  Cereda,  G  Foti,  M  Giacomini.  A  Pesenti.  Am 
J  Respir  Crit  Care  Med  1995:152:531. 

In  16  mechanically  ventilated  patients  with  acute 
lung  injury  (ALI)  (8  patients  with  moderate  ALI 
[moderate  group],  8  patients  with  severe  Al  .1  [adult 
respiratory  distress  syndrome,  ARDS  group]  I  and 
in  8  normal  anesthetized-paralyzed  subjects  (con 
trol  group),  we  partitioned  the  total  respiratory  sys- 


I  106 


Respiratory  Care:  •  November  "l)5  Vol  40  No  1 1 


Take  a  deep  breath 


You  will  never  miss  it  until  you  are  unable.  But  then  Hamilton  Medical  will  be  there  for  you. 
For  over  15  years  we  have  been  helping  accident  victims  and  the  critically  ill  breathe.  Our 
famous  VEOLARFT  and  AMADEUSFT  critical  care  ventilators  have  established  the  world 
standard  for  performance,  quality  and  value.  Our  instruments  are  technologically  advanced 
yet  intuitive.  We  were  the  ■■i^KJv  ,J^h;  .jhm  first  to  give  the  clinicians 
precise  views  of  thera-  peutic  breathing  patterns 

with  LEONARDO,  the  5Lfc£  advanced  Patient  Data  Ma- 


nager. The  VENTILAIR  is        |fi  "Tf^^jJ  the  quiet  medical  air  com- 

pressor.  The  MAX  is  the    I  j    spare  hands  for  emergency 

transport     ventilation.    ^^^»      w        WKUUKKr  Our  newest  product,  the 

ALADDIN  Infant  Flow  System,  is  a  remarkable  breakthrough  in  respiratory  treatment  of 
premature  infants.  Last,  but  not  least:  ARAMIS  is  the  user-friendly  Infusion  Pump.  In  Making 
Technology  Serve  Mankind,  we  strive  to  provide  solutions  which  are  innovative,  proficient 
and  competitive  in  the  international  market  place. 


sassL  t 


\ 

Iter^H 

'** 

M 

i 

i 

:  -, 

h  , 

m  ■■:. 


^*     '£ 


Circle  96  on  reader  service  card 
Visit  AARC  Booth  1232  in  Orlando 


HAMILTON 
MEDICAL 

MAKING  TECHNOLOGY  SERVE  MANKIND 


Manufacturer:  Hamilton  Medical  AG,  Via  Nova,  CH-7403  Rhazuns/Switzerland,  Telephone  (+41)  81- 37  26  27,  Telex  85131 1  cham  ch,  Fax  (+41)81-37  26  89 

USA:  Hamilton  Medical  Inc.,  P.O.Box  30008,  Reno,  NV  89520,  Telephone  (702)  858-3201,  (800)  HAM-MED-1,  Fax  (702)  856-5621 

Great  Britain:     Hamilton  (G.B.)  Limited,  Kimpton  Link  Business  Centre,  Kimpton  Road,  Sutton,  Surrey  SM3  9QP,  Telephone  0181-641  9008,  Fax  0181-641  9054 

Germany:  Hamilton  Deutschland  GmbH,  Postfach  110565,  D-64220  Darmstadt,  Tel.  (06151)  980  20,  Telex  419684,  Fax  (06151)  89  17  33 

For  all  other  countries  contact  Switzerland  or  our  local  distributor. 

Specifications  are  subject  to  alteration  without  prior  notice. 


Abstracts 


tern  mechanics  into  the  lung  (Ll  and  chest  wall 
(w)  mechanics  using  the  esophageal  balloon  tech- 
nique together  with  the  airway  occlusion  technique 
during  constant  flow  inflation.  We  measured  lung 
elastance  (Est.Ll.  chest  wall  elastance  (Est.w ),  and 
total  lung  (Rmax.L)  and  chest  wall  (Rmax.w)  re- 
sistance. Rmax.L  includes  airway  (Rmin.L)  and 
"additional"  lung  resistance  (DR.L).  DR.L  rep- 
resents the  "additional"  component  due  to  the  vis- 
coelastic  phenomena  of  the  lung  tissues  and  time- 
constant  inequalities  (pendelluft).  Measurements 
were  repeated  at  0,  5.  and  10  cm  HiO  of  positive 
end-expiratory  pressure  (PEEP)  in  the  control 
group  and  at  0, 5.  10,  and  15  cm  H;0  PEEP  in  pa- 
tients with  ALL  The  end-expiratory  lung  volume 
(EELV)  was  measured  at  each  level  of  PEEP.  Spe- 
cific total  lung  (sRmax.L).  airway  (sRmin.L).  and 
"additional"  lung  (sDR.L)  resistances  were  ob- 
tained as  Rmax.L  x  EELV,  Rmin.L  x  EELV.  and 
DR,L  x  EELV,  respectively.  At  PEEP  0  cm  H20, 
we  found  that  both  Est.L  (23.7  ±  5.5  and  13.8  ± 
3.3  versus  9.3  ±  1.7  cm  H-.0/L;  p  <  0.01 )  and  Estw 
(13.2  ±  5.4  and  9.9  ±  2.1  versus  5.6  ±  2.3  cm 
HiO/L;  p  <  0.01 )  were  markedly  increased  in  pa- 
tients with  ARDS  and  moderate  ALI  compared 
with  control  subjects,  with  a  significant  (p  <  0.01 ) 
effect  of  the  severity  of  the  disease  on  Est.L  (p  < 
0.01).  Rmax.L  was  significantly  (p<0.01)  high- 
er in  patients  with  ARDS  and  moderate  ALI  com- 
pared with  control  subjects,  because  of  an  increase 
in  Rmin.L  (4.4  ±  1.9  and  2.7  ±  1.3  versus  2.1  ± 
0.9  cm  H20/L/s;  p  <  0.01 ),  and  DR.L  (3.2  ± 0.8 
and  1.5  ±  1.1  versus  1.1  ±  0.6  cm  H20/L/s;  p  < 
0.01 ).  with  a  significant  effect  of  the  severity  of 
the  disease  (p  <  0.01).  Nevertheless,  SRmax.L 
sRmin.L,  and  sDR.L  were  not  significantly  dif- 
ferent between  groups.  In  patients  with  ALI,  PEEP 
higher  than  10  cm  H20  significantly  (p  <  0.01) 
increased  Rmax.L.  DR.L.  and  sDR.L  while  it  did 
not  affect  sRmin.L.  In  conclusion,  we  have  shown 
that  in  mechanically  ventilated  patients  with  ALI: 
1 )  not  only  lung  but  also  chest  wall  elastance  is 
increased;  2)  increased  total,  airway,  and  "addi- 
tional" lung  resistance  probably  reflects,  at  PEEP 
0  cm  H20,  a  reduction  in  lung  volume;  3)  the 
severity  of  the  disease  significantly  influenced  lung 
mechanics;  4 )  PEEP  higher  than  10  cm  H;0  sig- 
nificantly increased  both  total  and  "additional" 
lung  resistance. 

Nasal  Pressure  Support  Ventilation  Plus  Oxy- 
gen Compared  with  Oxygen  Therapy  Alone  in 
Hypercapnic  COPD— DJM  Jones,  EA  Paul, 
PW  Jones,  JA  Wedzicha.  Am  J  Respir  Crit  Care 
Med  1995:152:538. 

Non-invasive  ventilation  has  been  used  in  chron- 
ic respiratory  failure  due  to  chronic  obstructive 
pulmonary  disease  (COPD),  but  the  effect  of  the 
addition  of  nasal  positive-pressure  ventilation  to 
long-term  oxygen  therapy  (LTOT)  has  not  been 
determined.  We  report  a  randomized  crossover 
study  of  the  effect  of  the  combination  of  nasal  pres- 
sure support  ventilation  (NPSV)  and  domiciliary 


LTOT  as  compared  with  LTOT  alone  in  stable 
hypercapnic  COPD.  Fourteen  patients  were  stud- 
ied, with  values  (mean  ±  SD)  of  Pao:  of  45.3  ± 
5.7  mm  Hg,  Pace*  of  55.8  ±  3.6  mm  Hg.  and  FEV, 
of  0.86  ±  0.32  L.  A  4-week  run-in  period  (on  usual 
therapy)  was  followed  by  consecutive  3-month 
periods  of:  ( 1 )  oxygen  therapy  alone,  and  (2)  oxy- 
gen plus  NPSV  in  randomized  order.  Assessments 
were  made  during  run-in  and  at  the  end  of  each 
study  period.  There  were  significant  improvements 
in  daytime  arterial  Pao:  and  Paco:.  total  sleep  time, 
sleep  efficiency,  and  overnight  Paco:  following 
3  months  of  oxygen  plus  NPSV  as  compared  with 
run-in  and  oxygen  alone.  Quality  of  life  with  oxy- 
gen plus  NPSV  was  significantly  better  than  with 
oxygen  alone.  The  degree  of  improvement  in  day- 
time Paco:  was  correlated  with  the  improvement 
in  mean  overnight  PacO;-  Nasal  positive-pressure 
ventilation  may  be  a  useful  addition  to  LTOT  in 
stable  hypercapnic  COPD. 

Long-Term  Metered-Dose  Inhaler  Adherence 
in  a  Clinical  Trial — CS  Rand,  M  Nides, 
MK  Cowles.  RA  Wise,  J  Connett,  for  the  Lung 
Health  Study  Research  Group.  Am  J  Respir  Crit 
Care  Med  1995:152:580. 

Poor  adherence  to  medication  regimens  is  a  well- 
documented  phenomenon  in  clinical  practice  and 
an  ever-present  concern  in  clinical  trials.  Little 
is  known  about  adherence  to  inhaled  medication 
regimens  over  extended  periods.  The  present  paper 
describes  the  2-year  results  of  the  Lung  Health 
Study  (LHS)  program,  which  was  developed  to 
maintain  long-term  adherence  to  an  inhaled  med- 
ication regimen  in  3.923  special  intervention  par- 
ticipants (as  measured  by  self-report  and  medi- 
cation canister  weight).  The  LHS  is  a  double-blind, 
multicenter.  randomized  controlled  clinical  trial 
of  smoking  intervention  and  bronchodilator  ther- 
apy (ipratropium  bromide  or  placebo)  for  early 
intervention  in  chronic  obstructive  pulmonary  dis- 
ease (COPD).  At  the  first  4-month  follow-up  visit, 
nearly  70%  of  participants  reported  satisfactory 
or  better  adherence.  Over  the  next  1 8  months,  self- 
reported  satisfactory  or  better  adherence  declined 
to  about  60%.  Canister  weight  classified  adher- 
ence as  satisfactory  or  better  in  72%  of  partici- 
pants returning  all  canisters  at  1  year,  and  in  70% 
of  the  participants  returning  all  canisters  at  the  2- 
year  follow-up.  Self-reporting  confirmed  by  can- 
ister weight  classified  48%  of  participants  at  1  year 
as  showing  satisfactory  or  better  adherence. 
Overusers  were  50%  more  likely  than  others  to 
misrepresent  their  true  smoking  status,  suggest- 
ing that  canister  weights  indicating  overuse  may 
be  deceptive.  Results  of  multiple  logistic  regression 
analysis  indicate  that  the  best  compliance  was 
found  in  participants  who  were  married,  older, 
white,  had  more  severe  airways  obstruction,  less 
shortness  of  breath,  and  fewer  hospitalizations, 
and  who  had  not  been  confined  to  bed  for  respi- 
ratory illnesses.  In  summary,  a  structured  program 
for  promoting  adherence  to  an  inhaled  medica- 


tion regimen  was  successful  in  achieving  initial 
satisfactory  adherence  in  the  majority  of  partic- 
ipants; however,  adherence  declined  notably  from 
the  conclusion  of  this  program  to  the  first-year  fol- 
low-up, and  more  gradually  over  the  second  year. 

Etiology  of  Extubation  Failure  and  the  Pre- 
dictive Value  of  the  Rapid  Shallow  Breathing 
Index — SK  Epstein.  Am  J  Respir  Crit  Care  Med 
1995:152:545. 

Failure  of  weaning  from  mechanical  ventilation 
is  thought  to  result  from  an  imbalance  between 
respiratory  muscle  capacity  and  respiratory  de- 
mand. The  ratio  of  respiratory  rate  to  tidal  vol- 
ume (f/  Vj,  rapid  shallow  breathing  index)  dur- 
ing spontaneous  unsupported  respiration  increases 
when  this  imbalance  exists,  and  may  predict  the 
success  or  failure  of  weaning  from  mechanical  ven- 
tilation. Using  f/V-r,  Yang  and  Tobin  demonstrated 
a  positive  predictive  value  (PPV)  of  0.78  (f/VT 
<  105  and  weaning  success).  To  define  the  etiology 
of  the  20%  false-positive  rate  (FPR,  f/VT  <  105 
and  weaning  failure).  94  patients  who  had  an  f/Vj 
determined  prior  to  extubation  were  studied 
prospectively.  Of  84  patients  with  an  tTVy  <  100, 
14  required  reintubation  within  72  hours  of  ex- 
tubation (FPR  =  0.17.  PPV  =  0.83).  Extubation 
in  13  of  these  14  cases  failed  because  of  congestive 
heart  failure,  upper  airway  obstruction,  aspiration, 
encephalopathy,  or  the  development  of  a  new  pul- 
monary process.  Only  1  patient  needed  reintubation 
solely  because  of  the  original  respiratory  process. 
Of  10  patients  extubated  with  an  f/VT  >  100. 4  re- 
quired reintubation.  all  because  of  the  underly- 
ing respiratory  process.  This  study  confirms  the 
high  PPV  for  an  f/VT  <  100.  The  FPR  of  ap- 
proximately 0.20  is  best  explained  by  extubation 
failure  caused  by  processes  for  which  f/Vr  is  phys- 
iologically or  temporally  unlikely  to  predict  suc- 
cess or  failure.  The  negative  predictive  value  If/Vy 
>  100  but  extubation  success)  for  f/Vj  may  be 
lower  than  previously  reported. 

Comparison  of  Exogenous  Surfactants  in  the 
Treatment   of  Wood   Smoke   Inhalation — 

GF  Nieman,  AM  Paskanik.  RR  Fluck.  WR  Clark. 
Am  J  Respir  Crit  Care  Med  1995:152:597. 

The  goal  of  this  study  was  to  compare  the  ef- 
fectiveness of  the  exogenous  surfactants  Infasurf -' 
and  Exosurf"  re-establishing  surfactant  function 
inhibited  by  severe  smoke  inhalation.  Mongrel 
dogs  (n  =  17)  were  anesthetized,  placed  on  a  ven- 
tilator (40%  Oi),  and  surgically  prepared  for  hemo- 
dynamic and  blood  gas  measurements;  venous  ad- 
mixture (Qva/Qt)  and  static  lung  compliance 
(Cstat)  were  calculated.  At  the  conclusion  of  the 
experiment,  lung  samples  were  taken  for  lung 
water  and  dynamic  surface  tension  (D.st.  Wil- 
helmy  balance)  measurements.  Following  base- 
line measurements,  dogs  were  randomly  separated 
into  4  groups:  Group  I,  smoke  +  sham  instillation; 
Group  II.  smoke  +  saline  instillation;  Group  III, 


IDS 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


Ready  When  You  Are, 


Day  or  night,  no  other  blood  gas  system  in  the  world  demands  less. 
Or  delivers  more.  The  new  IL  1600™  Series  blood  gas/electrolytes 
system  is  ready  to  deliver  accurate  results  on  a  moment's  notice... 
a  level  of  readiness  and  availability  no  other  analyzer  can  match. 

The  lowest  overall  maintenance  of  any  blood  gas/electrolytes 
system  of  its  kind. 

New  maintenance-free  electrodes  with  prefilled  disposable  caps. 

FL's  exclusive  continuous  calibration  ensures  that  your  analyzer 
is  always  ready... with  answers  you  can  trust.  You  will  never  have  to 
redraw  a  patient  because  of  a  failed  calibration. 

Improved  operator  safety,  thanks  to  IL's  new  self-wiping  probe 
and  safer  sample  tip  area.  Circle  1 24  on  reader  service  card 

Visit  AARC  Booth  1208  in  Orlando 


Smaller  size  provides  more  usable  space  in  your  lab. 

IL  offers  five  upgradeable  models,  ranging  from  basic  blood  gas  to 
blood  gas/electrolytes.  You  can  also  extend  your  diagnostic  range  by 
interfacing  your  IL  1600  Series  analyzer  with  an  IL  482  CO-Oximeter™ 
system  for  a  comprehensive  profile  of  blood  oxygenation. 

To  experience  a  new  level  of  system  readiness,  see  a  demonstration 
of  the  new  IL  1600  Series  blood  gas/electrolytes  system.  Contact  your 
IL  representative,  or  call  toll  free:  1-800-955-9525;  Fax  1-617-861-1908. 


<©  1994  Instrumentation  Laboratory 
EL  1600  and  IL  482  CO-Oximeter  are 

trademarks  of  Instrumentation  Laboratory 


if 


Instrumentation 
Laboratory 


Abstracts 


smoke  +  Exosurf  instillation:  and  Group  IV. 
smoke  +  Infasurf  instillation.  The  surfactants  (In- 
fasurf and  Exosurf.  100  mg/kg)  or  saline  (same 
volume  as  surfactants)  were  instilled  into  the  lungs 
via  suction  catheter  immediately  following  smoke 
exposure.  Smoke  inhalation  caused  a  similar  in- 
crease in  QyVQt  antt  Wl  >n  P.i(>.'  and  Cstat  in  all 
groups  that  improved  only  with  Infasurf  instil- 
lation (Group  IV).  Dsi  was  significantly  improved 
by  Infasurf  compared  with  all  other  groups.  We 
conclude  that  Infasurf  restores  normal  Dst.  in- 
hibited by  wood  smoke,  improving  lung  function. 
Exosurf  w  as  ineffective  in  the  treatment  of  wood 
smoke  inhalation. 

Tuberculosis  Outbreak  among  Health-Care 
Workers  in  a  Community  Hospital — DE  Grif- 
fith. JL  Hardeman.  Y  Zhang,  RJ  Wallace, 
GH  Mazurek.  Am  J  Respir  Crit  Care  Med  1 995 : 
152:808. 

Twenty-nine  health-care  workers  (HCW|  were 
exposed  to  an  active  case  of  unrecognized  drug- 
susceptible  pulmonary  tuberculosis  in  a  com- 
munity hospital  for  as  long  as  2  hours  in  the  emer- 
gency room  and  10  hours  in  a  medical  intensive 
care  unit.  Twelve  of  the  29  exposed  HCW  could 
not  be  evaluated  for  tuberculosis  infection  because 
10  of  them  had  a  previously  positive  tuberculin 
skin  test  and  2  were  lost  to  follow-up.  Of  the  re- 
maining 17  tuberculin  skin  test  negative  HCW. 
1 3  (76%  I  either  converted  their  skin  test  to  pos- 
itive (10  HCW)  or  developed  active  disease  (3 
HCW )  after  exposure  to  the  index  case.  The  My- 
cobacterium tuberculosis  isolates  from  the  3  HCW 
had  identical  DNA  restriction  fragment  length 
polymorphism  (RFLP)  patterns  when  studied  by 
pulsed  field  gel  electrophoresis.  This  case  of  drug- 
susceptible  tuberculosis  was  associated  with  un- 
usually high  rates  of  tuberculosis  infection  and 
disease  in  HCW.  Prevention  of  similar  occurrences 
in  HCW  may  be  difficult  because  of  the  short  ex- 
posure time  required  for  transmission  of  tuber- 
culosis and  the  absence  of  consensus  on  optimal 
respiratory  protective  measures. 

A  Comparison  of  Severity  of  Illness  Scoring 
Systems  for  Intensive  Care  Unit  Patients:  Re- 
sults of  a  Multicenter,  Multinational  Study — 

X  Castella,  A  Artigas.  J  Bion,  A  Kari,  the  Euro- 
pean/North American  Severity  Study  Group.  Crit 
Care  Med  1995:23(8):  1327. 

OBJECTIVE:  To  compare  the  performance  of  3 
severit}  <>l  illness  scoring  systems  used  commonly 
for  intensive  care  unit  (ICU)  patients  in  a  large 
international  data  set.  The  systems  analyzed  were 
versions  II  and  III  of  the  Acute  Physiology  and 
Chronic  Health  Evaluation  (APACHE)  system, 
versions  I  and  II  of  the  Simplified  Acute  Phys- 
iology Score  (SAPS),  and  versions  1  and  II  of  the 
Mortality  Probability  Model  (MI'Mi,  computed 
at  admission  and  after  24  hours  in  the  ICU.  DE- 
SIGN: A  multicenter,  multinational  cohort  study. 


SETTING:  One  hundred  thirty-seven  ICUs  in  12 
European  and  North  American  countries.  PA- 
TIENTS: During  a  3-month  period.  14,745  pa- 
tients were  consecutively  admitted  to  137  ICUs 
enrolled  in  the  study.  INTERVENTIONS:  Col- 
lection of  information  necessary  to  compute  the 
APACHE  n  and  APACHE  III  scores.  SAPS  I  and 
SAPS  II,  and  MPM  I  and  MPM  II  scores.  Patients 
were  followed  until  hospital  discharge.  Statisti- 
cal comparison,  including  indices  of  calibration 
(goodness-of-fit)  and  discrimination  (area  under 
the  receiver  operating  characteristic  curve ).  MEA- 
SUREMENTS AND  MAIN  RESULTS:  Despite 
having  acceptable  receiver  operating  character- 
istic areas,  the  older  versions  of  the  systems  an- 
alyzed (APACHE  n,  SAPS,  and  MPM  I  computed 
at  admission-MPM  I  computed  after  24  hours  in 
the  ICU)  demonstrated  poor  calibration  for  the 
whole  database.  The  new  versions  of  the  systems 
(SAPS  II  and  MPM  II)  were  superior  to  their  older 
counterparts.  This  superiority  is  reflected  by  larg- 
er receiver  operating  characteristic  areas  and  bet- 
ter fit.  The  APACHE  III  system  improved  its  re- 
ceiver operating  characteristic  area  compared  with 
the  APACHE  II  system,  which  showed  the  best 
fit  of  the  old  systems  analyzed.  CONCLUSIONS: 
The  new  versions  of  the  severity  systems  analyzed 
(APACHE  III,  SAPS  II.  MPM  II)  perform  bet- 
ter than  their  older  counterparts  (APACHE  II, 
SAPS  I,  and  MPM  I).  APACHE  II,  SAPS  II,  and 
MPM  II  show  good  discrimination  and  calibra- 
tion in  this  international  database. 

Corticosteroid  Treatment  for  Sepsis:  A  Crit- 
ical Appraisal  and  Meta-Analysis  of  the  Lit- 
erature— L  Cronin,  DJ  Cook,  J  Carlet,  DK  Hey- 
land.  D  King,  MD  Lansang,  CJ  Fisher  Jr.  Crit  Care 
Med  1995:23(8):  1430. 

OBJECTIVE:  To  determine  the  effect  of  corti- 
costeroid therapy  on  morbidity  and  mortality  in 
patients  with  sepsis.  DATA  SOURCES:  We 
searched  for  published  and  unpublished  research 
using  MEDLINE,  EMBASE,  and  the  Science  Ci- 
tation Index,  manual  searching  of  Index  Medicus, 
citation  review  of  relevant  primary  and  review  ar- 
ticles, personal  files,  and  contact  with  primary  in- 
vestigators. STUDY  SELECTION:  From  a  pool 
of  1 24  potentially  relevant  articles,  duplicate  in- 
dependent review  identified  9  relevant,  random- 
ized, controlled  trials  of  corticosteroid  therapy  in 
sepsis  and  septic  shock  among  critically  ill  adults. 
DATA  EXTRACTION:  In  duplicate,  indepen- 
dently, we  abstracted  key  data  on  population,  inter- 
vention, outcome,  and  methodologic  quality  of 
the  randomized  controlled  trials.  DATA  SYN- 
THESIS: Corticosteroids  appear  to  increase  mor- 
tality in  patients  with  overwhelming  infection  (rel- 
ative risk  1.13.  95%  confidence  interval  0.99  to 
1 .29).  and  have  no  beneficial  effect  in  the  subgroup 
ul  patients  with  septic  shock  (relative  risk  1.07. 
95'  I  confidence  interval  0.91  to  1.26).  Studies  with 
the  highest  methodologic  quality  scores  also  sug 
gcsl  a  trend  toward  increased  mortality  overall  (rel- 


ative risk  1. 10,  95%  confidence  interval  0.94  to 
1.29).  A  similar  trend  was  observed  for  patients 
with  septic  shock  (relative  risk  1.12,  95%  con- 
fidence interval  0.95  to  1 .32 ).  No  difference  in  sec- 
ondary infection  rates  was  demonstrated  in  corti- 
costeroid-treated  patients  with  sepsis  or  septic 
shock.  However,  there  was  a  trend  toward  in- 
creased mortality  from  secondary  infections  in  pa- 
tients receiving  corticosteroids  (relative  risk  1.70, 
95%  confidence  interval  0.70  to  4.12).  The  oc- 
currence rate  of  gastrointestinal  bleeding  was  in- 
creased slightly  in  the  treatment  group  (relative 
risk  1.17,  95%  confidence  interval  0.79  to  1.73). 
CONCLUSIONS:  Current  evidence  provides  no 
support  for  the  use  of  corticosteroids  in  patients 
with  sepsis  or  septic  shock,  and  suggests  that  their 
use  may  be  harmful.  These  trials  underscore  the 
need  for  future  methodologically  rigorous  trials 
evaluating  new  immune-modulating  therapies  in 
well-defined  critically  ill  patients  with  over- 
whelming infection. 

The  Choice  of  Inhalers  in  Adults  and  Children 
over  Six— KR  Chapman.  J  Aerosol  Med  1995:8 
(Suppl2):S-27. 

Available  delivery  systems  for  ambulatory  use 
include  the  conventional  suspension  pressurized 
metered  dose  inhaler  (MD1),  the  conventional 
MDI  with  add-on  devices  such  as  spacing  cham- 
bers and  several  powder  delivery  systems.  Gas- 
driven  or  ultrasonic  nebulizers  are  also  available 
but  are  generally  reserved  for  in-hospital  use  or 
for  the  treatment  of  the  most  severely  obstruct- 
ed patients.  It  is  difficult  to  select  I  best  system 
for  use  in  older  children,  adolescents,  and  adults; 
all  available  systems  have  their  deficiencies,  and 
these  are  outlined  here.  The  most  widely  pre- 
scribed device,  the  MDI,  is  misused  by  some  pa- 
tients with  claims  of  up  to  one  third  of  clinic  pa- 
tients showing  inadequate  inhaler  technique.  In 
the  1990s,  the  MDI  has  also  been  criticized  for 
liberating  chlorofluorocarbons  (CFCs).  On  oc- 
casion, the  adjuvants  are  said  to  precipitate  cough. 
In  some  countries,  the  production  of  generic  or 
second  entry  inhalers  has  been  accompanied  by 
vexing  concerns  over  the  bioequivalence  of  ther- 
apeutic aerosols.  The  problem  of  patient  coor- 
dination with  the  inhaler  is  meant  to  be  dealt  with 
by  a  variety  of  add-on  devices.  Spacing  chambers 
and  reservoir  systems  improve  drug  delivery  and 
treatment  efficacy  for  some  patients.  Unfortu- 
nately, there  are  relatively  few  data  on  patient  spac- 
er technique  or  optimal  teaching  methods.  There 
is  considerable  potential  for  patient  misuse  of  these 
superficially  simple  devices.  One  common  prob- 
lem is  that  the  devices  become  dirty  and  worn  but 
are  seldom  replaced  by  patients.  A  more  subtle 
problem  is  electrostatic  drug  adherence  to  the  spac- 
ing chamber  thereby  reducing  drug  delivery.  This 
is  particularly  likely  to  happen  after  the  device 
is  washed  il  it  is  rubbed  dry  with  a  cloth  rather 
than  air-dried.  The  most  obvious  problems,  how  - 
ever,  concern  patient  compliance.  Spacing  cham- 


II  10 


Respiratory  Care  •  November  "95  vol  40  no  i 


Newport's  Wave  VM200 

ventilator  is  designed  to 

quickly  wean  even  the  most 

difficult  patients. 

Effectively  weaning  your  patients 
from  mechanical  ventilation  is  critical 
to  returning  them  to  productive,  healthy 
lifestyles.  Inefficient  ventilation  can  not 
only  delay  a  patient's  recovery,  but  can 
increase  hospital  costs.  The  Wave 
VM200  provides  the  information  and 
tools  you  need  to  make  simple  adjust- 
ments for  superior  patient  weaning. 


Tools  to 

Synchronize  Patient 

and  Ventilator 

For  example,  the  Peak  Inspira 
tory  Flow  Monitor  enables  you  to 
assess  the  adequacy  of  mechanical 
flow  versus  patient  flow  demand 
and  adjust  accordingly. 


Using  the  Peak  Expiratory  Flow 
Monitor  can  help  you  determine  if  a 
filter  is  clogged,  assess  a  response  to  a 
bronchodilator  and  observe  changes  in 
compliance  and  resistance  through 

increased  or  decreased 
peak  flows.  By  making 
appropriate  adjust- 
ments on  the  ventilator  you 
can  lessen  the  chance  for  auto- 
PEEP  and  decrease  work  to 
trigger  the  ventilator. 

Also  facilitating 
recovery  is  our  Predic- 
tive Learning  Logic 


software  which  automatically  antici- 
pates the  natural  lung  movement  and 
works  with  the  patient  to  decrease 
breathing  effort  and  reduce  stress.  And 
working  in  any  ventilator  mode,  our 
unique  Bias  Flow  decreases  ventilator 
response  time  and  stabilizes  baseline 
pressure. 

Call  today  for  a  complimentary 
demonstration  of  the  Wave  VM200, 
number  one  for  patient  weaning. 


nig 


Newport  Medical  instruments,  Inc. 

Post  Office  Box  2600,  Newport  Beach,  CA  92658 

800.451.3111    714.642.3910 

Fax  714. 548. 3091 


Circle  131  on  reader  service  card 
Visit  AARC  Booth  742  in  Orlando 


Abstracts 


hers  reduce  the  patient's  perception  of  aerosol  de- 
livery; although  this  may  minimize  the  unpleasant 
taste  of  some  drugs,  many  patients  confuse  this 
with  decreased  efficacy  unless  they  are  warned 
about  it.  This  factor  and  the  bulkiness  of  some  de- 
vices would  tend  to  reduce  compliance.  Dry  pow- 
der systems  are  available  in  several  formats  but 
may  offer  uncertain  drug  delivery  in  the  presence 
of  low  flow  or  high  humidity  conditions.  The  need 
to  load  powder  inhalers  may  be  cumbersome.  With 
some  powder  delivery  systems,  such  as  the  Turbu- 
haler™,  the  patient's  failure  to  perceive  drug  de- 
livery is  sometimes  a  cause  for  poor  compliance. 
There  are  fewer  data  describing  patient  use  of 
powder  inhalers  than  for  the  MDIs  that  have  been 
in  longer  use.  With  these  various  shortcomings 
for  each  of  the  available  delivery  systems,  it  is 
fair  to  say  that  no  single  system  is  suitable  for  all 
patients.  The  MDI  is  probably  suitable  with  good 
efficacy  in  80-90%  of  adult  patients  if  appropriate 
teaching  is  offered.  For  the  minority  of  patients 
unable  to  use  the  conventional  MDI  adequately, 
an  add-on  device  or  powder  delivery  system  is 
available  as  an  alternative.  With  no  single  delivery 
system  to  be  recommended  universally,  it  is  in- 
cumbent upon  the  physician  or  caregiver  to  as- 
sess the  patient's  ability  to  use  various  inhalers 
effectively  and  to  determine  patient  preference. 
Regrettably,  academic  medicine  has  generally 
failed  in  its  duty  to  train  medical  professionals 
in  this  essential  task. 

Babyhaler:  A  New  Pediatric  Aerosol  Device — 

R  Kraemer.  J  Aerosol  Med  1995;8(Suppl  2):S-19. 

Nebulizers  have,  until  recently,  been  the  main- 
stay of  drug  delivery  by  inhalation  in  babies  and 
young  children.  The  willingness  of  a  young  child 
to  cooperate,  however,  is  limited  and  the  10-12 
minutes  needed  to  deliver  drug  using  a  nebuliz- 
er often  limits  the  compliance  with  this  mode  of 
administration  in  infants.  Therefore,  drug  deliv- 
ery systems  using  the  metered-dose  inhaler  (MDI) 
as  the  aerosol  generator  attached  to  valved  hold- 
ing chambers  were  developed.  The  breathing  pat- 
tern of  a  baby  with  lung  disease  is  quite  differ- 
ent from  that  of  older  children  and  adults,  for 
whom  most  large-volume  devices  were  developed. 
Infants  have  a  high  respiratory  frequency,  small 
tidal  volume,  and  low  inspiratory  airflow  rate. 
Therefore,  specific  conditions  for  optimal  drug 
use  in  this  particular  group  of  patients  have  to  be 
met.  Efficacy  of  topical  drug  delivery  depends  on 
the  generation  of  aerosol  particles  with  an  ade- 
quate size  distribution  (technical  prerequisites), 
the  breathing  pattern  of  the  child  (physiological 


requirements),  and  the  willingness  of  a  young  child 
to  cooperate  with  parental  drug  administration 
(practicality  and  compliance).  Infants  with  lung 
disease  have  a  tidal  volume  of  8- 10  mL/kg  body 
weight.  The  volume  of  a  spacer  device  must  be 
such  that  about  5-10  breaths  would  be  needed  to 
provide  an  adequate  dose.  In  addition,  the  dimen- 
sions of  a  spacer  device  must  be  such  that  suffi- 
cient drug  particles  of  optimal  size  will  be  gener- 
ated to  minimize  impaction  and  deposition  w  ithin 
the  device.  The  Babyhaler  consists  of  a  tubular 
chamber  230  mm  long,  with  a  volume  of  350  mL 
and  low-resistance  inspiratory  and  expiratory 
valves.  The  drug  aerosol,  which  has  a  mass  me- 
dian diameter  of  3.2 1  /an.  is  contained  briefly  with- 
in the  holding  chamber  to  allow  the  young  child 
to  inhale  the  medication  during  normal  tidal  breath- 
ing. Face  masks  used  in  conjunction  with  the  Baby- 
haler provide  an  effective  seal.  The  overall  dead 
space  volume  was  found  to  be  approximately  55 
mL.  Efficacy  was  demonstrated  in  several  clin- 
ical trials  that  evaluated  bronchodilator  response 
to  /Ji-agonists,  functional  antagonism  against 
bronchial  aerosol  challenge  and  efficacy  of  top- 
ical corticosteroids.  These  results  plus  addition- 
al handling  studies  have  demonstrated  that  infants 
and  young  children  can  be  treated  using  the  in- 
halation route,  and  several  important  practical  prob- 
lems which  previously  limited  drug  compliance 
have  been  overcome. 

The  Diskus™:  A  New  Multi-Dose  Powder  De- 
vice— Efficacy  and  Comparison  with  Tur- 
buhaler™— R  Fuller.  J  Aerosol  Med  1995;8 

(Suppl2):S-ll. 

The  Diskus  is  a  novel  multi-dose  powder  inhaler 
for  the  treatment  of  asthma,  delivering  precise  in- 
dividual doses  of  drug  to  allow  the  'average'  pa- 
tient a  month's  therapy.  It  was  designed  to  be  sim- 
ple to  operate  and  contains  a  dose  counter.  The 
performance  of  the  Diskus  has  been  compared  with 
that  of  a  well-established  reservoir  powder  inhaler. 
The  pharmaceutical  assessment  of  the  Diskus  has 
shown  that  the  delivered  dose  of  salmeterol  and 
fluticasone  propionate  (FP)  remains  at  approxi- 
mately 90%  of  the  labeled  claim  at  a  range  of  flow 
rates  of  30-90  L/min.  This  contrasts  with  data  for 
the  reservoir  powder  inhaler  which  show  that  the 
delivered  dose  as  a  percentage  of  the  labeled  claim 
is  both  lower  and  more  variable,  particularly  at  flow 
rates  between  30  and  60  L/min.  The  mass  of  drug 
substance  (mass  median  aerodynamic  diameter 
(MMAD).  <  6  /an)  delivered  from  the  Diskus  also 
remains  relatively  constant  at  different  flow  rates, 
unlike  the  reservoir  powder  inhaler,  in  which  the 


tine  particle  mass  is  more  dependent  on  flow  rate. 
The  doses  of  drug  in  the  Diskus  are  protected  from 
moisture;  the  tine  particle  mass  of  salmeterol  de- 
livered from  the  Diskus  is  unaffected  by  humid 
conditions  (30°C/75%  relative  humidity)  as  op- 
posed to  the  reservoir  powder  inhaler  in  which  the 
ingress  of  moisture  is  associated  with  a  decrease 
in  particles  of  MMAD  <  6  /an.  In  clinical  stud- 
ies, salmeterol,  50  /tg  twice  daily,  and  FP.  50-500 
//g  twice  daily,  have  been  shown  to  be  equally  ef- 
fective and  well  tolerated  when  delivered  by  Diskus 
as  compared  with  Diskhaler.  More  recently.  FP. 
200  /fg  a  day.  delivered  via  Diskus  has  been  shown 
to  be  more  effective  and  as  safe  as  budesonide. 
400  ng  a  day,  delivered  via  the  reservoir  powder 
inhaler.  Furthermore,  handling  data  show  the 
Diskus  is  well  liked  by  patients  and  was  found  easy 
to  use  by  patients  aged  between  16  and  70  years. 
It  is  also  an  easy  device  to  learn  to  use  and  teach. 
In  direct  comparison  with  the  reservoir  powder 
inhaler,  patients  preferred  the  Diskus  overall  and 
specifically  with  respect  to  ease  of  use  and  the  pres- 
ence of  a  dose  counter. 

Standard  Flow-Time  Waveforms  for  Testing 
of  PEF  Meters— JL  Hankinson,  RO  Crapo.  Am 
J  Respir  Crit  Care  Med  1995,152:696. 

The  American  Thoracic  Society  (ATS)  has  rec- 
ommended the  use  of  24  volume-time  waveforms 
for  the  testing  of  spirometers.  Although  these 
waveforms  include  values  of  peak  expiratory  flow 
(PEF).  they  were  not  originally  intended  to  test 
PEF  meters  but.  rather,  volume  parameters  for 
spirometers.  In  addition,  the  practice  of  using  ATS 
volume-time  Waveform  24  with  varying  multi- 
plying factors  does  not  provide  the  range  of  flow- 
time  waveform  shapes  (rise  times)  needed  to  eval- 
uate PEF  meters.  Accordingly,  we  have  developed 
a  set  of  26  flow-time  waveforms  specifically  se- 
lected to  evaluate  PEF  meters.  PEF  and  other  flow 
parameters  (rise  time  and  time  to  PEF)  can  be  di- 
rectly measured  from  these  flowtime  waveforms. 
When  PEF  determined  directly  from  the  flow-time 
curve  was  compared  with  PEF  determined  indi- 
rectly from  a  volume-time  curve  (ATS  recom- 
mended algorithm  with  an  80  ms  time  segment), 
as  much  as  a  10.7%  difference  between  the  2  meth- 
ods was  observed  using  a  waveform  with  a  fast 
rise  time.  In  contrast,  there  was  very  little  dif- 
ference between  the  various  methods  of  deriving 
PEF  for  waveforms  with  slower  rise  times.  These 
26  flow-time  waveforms  provide  a  means  of  defin- 
ing PEF  for  the  testing  of  software  algorithms  and 
the  testing  of  PEF  meters  w  ith  computer-driven 
mechanical  pumps. 


1112 


RlSI'lk AIORY  C'AKI    •  NOVEMBER  '45  Vol    40  No 


Saunders'  strategies  for  success... 


ENTRY  LEVEL  RESPIRATORY 
CARE  REVIEW:  Study  Guide 
and  Workbook,  2nd  Edition 

Reviews  the  material  you  need  to;T  * 
know  for  the  NBRC  certification     h^ 
exam. ..then  challenges  your 
understanding  with  short-answer 
questions  and  problems.  Also 
features  a  post-test,  test-taking  tips, 
more!  Based  on  the  current  exam 
content  matrix. 

By  Gary  Persing,  BS,  RRT  Nov.  1995.  Over  320  pp. 
Illustd.  Soft  cover.  S36.95  Order  #W6426-1 

FLIP  AND  SEE  ECC  |a^| 

Master  3-lead  ECG  recognition'-w^ 
and  interpretation  in  less  than  two 
hours!  An  easy-to-follow,  interactive 
format  helps  you  quickly  progress 
from  basic  anatomy  and  physiology 
to  more  advanced  concepts. 
Includes  a  free  pocket  guide  to 
interpretation. 

Bv  Elizabeth  Gross  Cohn,  RN,  CEN,  EMT-CC;  & 
Mary  Gilroy-Doohan,  MD.  Oct.  1995.  Over  140  pp. 
Over  140  ills.  Soft  cover  $19.95.  Order  #W5834-2. 


COMPREHENSIVE 
RESPIRATORY  CARE 

Groundbreaking  book  blends 
respiratory  care  with  critical  care! 
71  experts  from  every  relevant 
discipline  help  you  to  recognize 
and  respond  to  life-threatening 
problems  with  greater  confidence, 
speed,  and  success. 

Edited  by  David  R.  Dantzker,  MD; 
Neil  R.  Maclntyre,  MD;  &  Eric  D.  Bakow, 
MA,  RRT,  with  71  contributors,  1995. 1344  pp 
812  ills.  559.00.  Order  #W2844-3. 

PERINATAL  AND  ^k 
PEDIATRIC  V^ 

RESPIRATORY  CARE 

Looks  at  the  principles  of 
respiratory  care.. .and  how  to 
apply  them  in  practice. ..so  you'll 
be  better  prepared  to  manage  a 
full  range  of  conditions.  A  great 
review  for  the  specialty  certifying 
exam! 

Edited  bv  Sherry  L.  Barnhart,  AS,  RRT,  & 
Michael  P.  Czervinske,  BSRT,  RRT;  with  66 
contributors.  Mar.  1995.  731  pp.  522  ills.  $47.00. 
Order  #W6739-2. 


LEARNING  STRATEGIES  FOR  f«e3, 
ALLIED  HEALTH  STUDENTS    V^ 

Helps  vou  build  the  skills  you  need  to 
score  to  your  potential  on  exams. ..increase 
your  vocabulary. ..get  more  out  of  every- 
thing you  read. ..organize  your  ideas  so 
you  can  write  clearly  and  effectively... 
much  more! 

Bv  Susan  Marcus  Patau,  MA;  &  Marilyn  Meltzer,  MA.  Sept. 
1995.  Over  365  pp.  Illustd.  Soft  cover.  $24.95.  Order  #W5603-X. 

PHARMACOLOGY  AND 
THERAPEUTICS  IN 
RESPIRATORY  CARE 

Must-have  guide  to  drugs  now  in  use, 
awaiting  FDA  approval,  and  being  tested 
in  emerging  and  experimental  therapies. 
Appendices  include  ratios  and  equivalents, 
respiratory  drugs  administered  by 
inhalation,  more. 

Bv  Theodore  J.  Witek,  Jr.,  DrPH;  k  E.  Neil  Schachter, 
MD.  1994. 490  pp.  398  ills,  (with  162  in  2-color)  $4195. 
Order  #W3483-4. 


Call  Toll- Free 
1  800  545  2522 

(8:30-7:00  Eastern  Time)  to  order. 
Be  sure  to  mention  DM#33565. 


lPt   YES!  Please  send  my  copy  of  the  book(s)  checked.  If  not 
completely  satisfied,  I  may  return  the  book(s)  with  the  invoice  within  30 
days  with  no  further  obligation. 
~  Bill  me  later      Z  Check  enclosed  VISA      D  MC      DAmEx 

Card# / / / Exp.  date / 

Add  the  applicable  sales  tax  tor  your  area  Prepaid  orders  save  shipping  Make  checks  payable  to 
W.B.  SAUNDERS  COMPANY.  Staple  this  to  your  purchase  order  to  expedite  delivery. 


W6426-1  Persing,  2nd  Ed.  $36.95 
W5834-2  Cohn  &  Gilroy-Doohan  $19.95 

□  W2844-3  Dantzker  et  al.  $59.00 

LI  W6739-2  Barnhart  &  Czervinske  $47.00 

□  W5603-X  Palau  &  Meltzer  $24.95 
W3483-4  Witek  &  Schachter  $41.95 
Also  send: 

W2859-1  Dorland's  ILLUSTRATED  MEDICAL 
DICTIONARY,  28th  Edition  $39.95 


..Telephone  ( . 


_City 


-Zip 


3W.B.  SAUNDERS  COMPANY  1995  Professional  references  may  be  tax-deductible  Offer  valid  in  USA  only  Prices  subject  to  change  without  notice. 

W.B.  SAUNDERS  COMPANY 

A  Division  of  Harcouri  Brace  &  Company 

Order  Fulfillment  Department  •  6277  Sea  Harbor  Drive  •  Orlando,  Florida  32887 


RC  1 1/95   DMS33565 


Circle  132  on  reader  service  card 
Visit  AARC  Booth  646  in  Orlando 


Peak 


Momtorm 


Patented  flow-sampling 
technology  minimizes 
wear...  maximizes 
accuracy  and 
reproducibility 


Sterilizable.. 
dishwasher-safe 


The  self-contained 
carrying  case... 


Meets  NAEP 
Technical  Standards 


Xorget  everything 
you  know  about  peak 
flow  meters. 

We  did.  Keeping 
only  the  proven  accuracy 
of  our  exclusive  flow-sampling  technology, 
we  set  out  to  build  an  entirely  new  kind  of 
peak  flow  meter 
The  result  is  Personal  Best"' 
—  the  revolutionary  new 
meter  that's  changing  the 
tape  of  peak  flow  monitonng 
Wherever 
Personal  Best  goes — in  the 
hospital,  office,  or  home 
it  sets  a  new  standard  foi 
convenience,  complianci 
and  confidence.  ...makes  using 

Personal  Best  child''. 


Easy-to-read  scale  —  available  in 
Full  (60-810  L/min)  and 
Low  (50-390  L  Imin)  ranges 


And  Personal  Best  goes 
anywhere. ..easily.  With  a  light- 
weight, self-contained,  portable 
design  that  puts  peak  flow 
monitonng  at  your  fingertips  — 
or  your  patients'  —  all  day  long 

Plus  a  rugged,  sterilizable 
construction  that  helps  it  stand  up  to  the 
roughest  use  day  after  day 

Personal  Best  encourages  compliance 
with  its  comfortable  oval  mouthpiece  and 
easy-to-use  built-in  handle.      Comprehensiv 
And  it  improves  patient 
communication  with  its 
high-legibility  scale  and 
NAEP-endorsed  Three- 
Zone  Management  System. 


play. 


Flow 
Redefined. 


High-impact  ABS  plastic 
construction,  surgical  stainless  steel 
moving  parts  — jor  reliable,  cost- 
effective  performance 


Foldout  handle  keeps  hands  away 
from  airstream  —  ensures  proper 
technique  for  accurate  readings 


Most  important,  Personal  Best 

provides  accurate,  instant 
r  Better  fit. 

airflow  measurements  that         Better  comfort 
may  be  used  by  healthcare         Better  seal. 
professionals  to  guide  patient  screening, 
emergency  assessment,  discharge  instruction, 

medication  adjustment,  and 

home  monitonng. 


Unique  oval  mouthpiece  — 
easier  and  more  comfortable  for 
patients  to  use 


Get  your  hands 
on  Personal  Best, 
and  expenence  the 
difference  for 
yourself.  Call 
1-800-962-1266 
toll-free.  Or  drop  this 
coupon  in  the  mail. 


Instruction  card 
fits  inside  handle. 


r 


Steri/izable 
construction 
and  disposable 
mouthpieces  make 
multi-patient 
screening  a  snap. 


PeAAxmcU  Qe&t* 


RC 11/95 

Peak  Flow  Meter 
Redefining  peak  flow  monitoring. 

I  want  to  experience  the  Personal  Best  difference  first-hand. 


City 


State 


ZIP 


Telephone  ©  1995  HealtKSan  Products  Inc  PA755002-2 

HealthScan  Products  Inc.  •  908  Pompton  Avenue  •  Cedar  Grove,  NJ  07009-1292  USA 
1-800-962-1266  FAX  (201)  239-0831 


Circle  129  on  reader  service  card 
Visit  AARC  Booth  1310  in  Orlando 


Editorials 


Quiet — Hospital  Zone: 
Why  We  Should  Reduce  Noise  Levels  in  the  Hospital 


The  utilization  of  technology  and  personnel  in  modem  hos- 
pitals contributes  to  noise  pollution  and  excessive  noise  ex- 
posure for  our  patients.  Noise  levels  in  hospitals  have  increased 
in  recent  years,  often  exceed  safe  or  comfortable  levels,  and 
can  result  in  noise-induced  hearing  loss.1"3  Respiratory  care 
practitioners  and  other  health  care  professionals  should  be  con- 
cerned about  the  contribution  of  their  equipment  and  prac- 
tices to  noise  levels  in  the  hospital  environment.  Not  only  can 
noise  increase  patients'  risk  for  hearing  loss,  but  it  also  caus- 
es physiologic  stress.4"6  Noise  directly  contributes  to  physio- 
logic stress  by  causing  increased  blood  pressure,  heart  rhythm 
changes,  dilation  of  blood  vessels,  and  increased  secretion  of 
stomach  acid.4  7  It  has  also  been  documented  that  noise  rais- 
es intracranial  pressure  in  infants.5  Noise  indirectly  contributes 
to  physiologic  stress  by  interfering  with  sleep.2,8,9  Sleep  is  es- 
sential to  restore  and  maintain  physiologic  and  mental  health. 
It  has  also  been  shown  how  stress  and  sleep  deprivation  con- 
tribute to  illness  and  interferes  with  the  ability  of  the  body  to 
heal  itself. 

Infants  are  particularly  susceptible  to  the  damaging  ef- 
fects of  noise  because  of  the  immaturity  of  the  developing 
ear.  Table  1  shows  how  various  technology,  procedures,  and 
practices  contribute  to  noise  in  neonatal  intensive  care  units 
(NICUs).'1  Health  care  practitioners  can  implement  many 
changes  to  reduce  noise  in  our  hospitals,  including  NICUs. 
We've  probably  all  been  guilty  of  slamming  incubator  doors, 
dropping  charts  on  hard-surfaced  desk  tops,  drumming  our 
fingers  on  incubator  canopies  or  bed  rails,  and  calling  across 
an  already  noisy  room.  Noise  should  not  be  used  as  a  stimu- 
lus during  apneic  episodes;  alternative  procedures  for  stim- 
ulating breathing  in  newborns  should  be  used.  Our  study1" 
published  in  this  issue  of  the  Journal  reports  on  the  type  of 
noise  produced  by  humidifiers  and  nebulizers  used  with  hoods 
in  the  NICU.  We  offer  several  recommendations  to  minimize 
noise  exposure  when  oxygen  and  humidity  is  needed  in  the 
care  of  newborns.  We  found  that  heated  humidifiers  should 
be  used  in  NICUs  because  they  can  significantly  decrease 
infants'  exposure  to  noise.  Furthermore,  hoods,  incubators, 
and  Other  equipment  with  noise-reduction  features  should  be 
used  whenever  possible. 


Sound  Levels  Measured  in  Deeihels  (dB)  in  Neonatal 
Intensive  Care  Units* 


Location                                        Average  (dB) 

Peak(dB) 

Room 

Quiet 

58-62 

— 

Talking 

58-64 

— 

Radio 

60-62 

— 

Intravenous  pump  alarm 

61 

78 

Sink  on/off 

66 

76 

Inside  Incubator 

Using  hood  top  as  a  writing  surface 

59 

64 

Incubator  alarm 

67 

67 

Motor  off 

38-42 

71 

Motor  on 

55 

71 

Intravenous  pump  alarm 

56 

76 

Bumping  a  metal  vvastebasket 

62 

85 

Opening  a  plastic  sleeve 

67 

86 

Bubbling  in  ventilator  tubing 

62 

87 

A  bradycardia  alarm 

55 

88 

Tapping  hood  with  fingers 

70 

95 

Closing  an  incubator  cabinet 

70 

95 

Setting  a  plastic  feeding  bottle  on  canopy 

84 

108 

Closing  a  solid  plastic  porthole 

80 

111 

Dropping  the  head  of  a  mattress 

88 

117 

*  Adapted  from  Reference  9,  with  permission 

Other  studies  have  demonstrated  how  suctioning  equip- 
ment and  alarms  can  significantly  increase  noise  exposure  in 
the  hospital  environment.12'1  Ii:  Consequently,  alarms  should 
be  set  at  the  lowest  audible  setting  with  the  longest  feasible 
time  delay.  Also,  effective  suctioning  practices  are  crucial  so 
that  frequency  of  the  procedure  can  be  reduced  and  unneces- 
sary suctioning  can  be  eliminated.  Authors  have  also  reported 
reduction  of  the  high  noise  levels  caused  by  the  motor  and 
fan  of  incubators  by  replacing  the  motor  with  one  of  higher 
quality,  by  trimming  and  balancing  the  fan  blades,  and  by  elim- 
inating sharp  edges  of  the  airduct.13  The  study  of  "noise-in- 
duced  hypoxemia"  and  elevation  of  intracranial  pressure  should 
be  looked  upon  as  a  potential  hazard  of  excessive  incubator 
noise  of  short  duration.5  Research  is  needed  to  evaluate  in- 


II  If. 


RhSIMRATORY  C'ARI    •  NOYLMBHR  '95  VOL  40  NO  I  1 


Editorial 


cubator  design  and  use  in  order  to  reduce  infants'  noise  ex- 
posure in  the  NICU.  Further  research  and  changes  in  prac- 
tice are  also  needed  to  protect  our  patients  from  the  health  risks 
associated  with  noise  exposure  in  our  hospitals. 

Shelley  C  Mishoe  PhD  RRT 

Associate  Professor  &  Chair 

Department  of  Respiratory  Therapy 

Medical  College  of  Georgia 

Augusta,  Georgia 


REFERENCES 

Balogh  D,  Kittinger  E,  Benzer  A,  Hackl  JM.  Noise  in  the  ICU.  In- 
tensive Care  Med  1993;19(6):343-346. 

Aitken  RJ.  Quantitative  noise  analysis  in  a  modern  hospital.  Arch 
Environ  Health  1982;37(6):361-364. 

Gottfried  AW,  Hodgman  JE.  How  intensive  is  newborn  intensive  care? 
An  environmental  analysis.  Pediatrics  I984;74(2):292-294. 


Falk  SA,  Woods  NF.  Hospital  noise-levels  and  potential  health  haz- 
ards. N  Engl  J  Med  1973;289(15):774-780. 
Long  JG.  Lucey  JF,  Philip  AG.  Noise  and  hypoxemia  in  the  inten- 
sive care  nursery.  Pediatrics  1980;65(1):  143-145. 
Field  T.  Alleviating  stress  in  newborn  infants  in  the  intensive  care 
units.  Clins  Perinatol  1 990;  1 7(  1 ):  1  -9. 

Baker  CF.  Sensory  overload  and  noise  in  the  ICU:  sources  of  en- 
vironmental stress.  Crit  Care  Q  1984;6:66-80. 
Topf  M,  Davis  JE.  Critical  care  unit  noise  and  rapid  eye  movement 
(REM)  sleep.  Heart  Lung  1993;22(3):252-258. 
Thomas  KA.  How  the  NICU  environment  sounds  to  a  preterm  in- 
fant. MCN  Am  J  Matern  Chil  Nurs  1989;14(4):249-251. 
Mishoe  SC,  Brooks  CW  Jr,  Dennison  FH,  Hill  KV,  Frye  T.  Octave 
waveband  analysis  to  determine  sound  frequencies  and  intensities 
produced  by  nebulizers  and  humidifiers  used  with  hoods.  Respir  Care 
1995;40(11):1 120-1 124. 

Bess  FH,  Peek  BF,  Chapman  JJ.  Further  observations  on  noise  lev- 
els in  infant  incubators.  Pediatrics  1979;63(1):100-106. 
Hyde  BB.  McCown  DE.  Classical  conditioning  in  neonatal  inten- 
sive care  nurseries.  Pediatr  Nurs  1986;12(1):1 1-14. 
13.  Michaelsson  M,  Riesenfeld  T,  Sagren  A.  High  noise  levels  in  infant 
incubators  can  be  reduced  (communication).  Acta  Pediatr  1992;81 
(10):843-844. 


10 


11 


12 


41st  Annual  Convention  and  Exhibition 
December  2-5  •  Orlando,  Florida 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


First,  Do  No  Harm: 
Balancing  the  Risks  and  Benefits  of  Medical  Procedures 


The  Hippocratic  admonition  to  "First,  do  no  harm"  is  fre- 
quently forgotten  today  because  we  believe  that  greater  good 
can  be  achieved  with  invasive  (and  often  dangerous)  treat- 
ments. In  Hippocrates's  day,  cure  was  rare;  diagnosis  and 
prognosis  were  the  only  contributions  made  by  the  physi- 
cian. But  even  today  with  the  chance  of  cure,  it  is  imper- 
ative that  we  keep  the  possible  negative  consequences  of 
our  treatments  in  mind.  Unintended  and  incidental  damage 
can  occur  to  many  body  structures  even  during  minimal- 
ly invasive  procedures. 

In  this  issue  of  the  Journal,  Dr  Watson1  reports  medi- 
an nerve  damage  from  brachial  artery  puncture — a  rare 
complication  of  arterial  blood  sampling.  The  author  iden- 
tifies several  aspects  about  the  brachial  artery  that  may  make 
it  a  more  hazardous  route  for  arterial  blood  sampling  than 
the  radial  artery.  This  case  reminds  us  all  of  the  possibil- 
ity of  inadvertent  patient  harm  often  present  even  with  'rou- 
tine' procedures. 

With  arterial  blood  sampling,  clinically  important  neg- 
ative consequences  are  rarely  seen.  The  safety  of  this  pro- 
cedure is  taken  for  granted  by  most  of  us.  Few  respira- 
tory care  practitioners  will  ever  see  a  patient  with  the  se- 
vere neurologic  complication  from  arterial  blood  gas 
sampling  described. 

This  case  report  is  a  compelling  example  of  why  it  is  im- 
portant to  balance  the  risks  with  the  benefits  of  any  inva- 
sive procedure.  In  addition,  minimizing  risks  is  important 
after  deciding  the  invasive  procedure  or  test  is  to  be  per- 
formed. Skill  and  knowledge  are  elements  that  reduce  risk. 
A  working  understanding  of  the  3-dimensional  anatomy  of 
the  area  being  invaded  will  help  the  respiratory  care  prac- 
titioner anticipate  and  detect  potential  problems.  Peripheral 
nerves  are  located  near  many  sites  used  for  arterial  sampling. 
Understanding  the  symptoms  of  nerve  injury  and  the  ap- 
propriate therapy  is  essential  when  performing  arterial  punc- 
ture at  any  site.  Nerve  damage  may  be  caused  by  direct  trau- 
ma from  the  needle  or  from  hematoma  formation  after  ar- 
terial penetration. 

Paresthesias  are  hallmarks  of  nerve  trauma  and  may  occur 
when  a  needle  is  inserted  for  arterial  blood  sampling.  A  pares- 


thesia is  a  sharp,  shooting,  electrical-type  pain  that  radiates 
distally  from  the  insertion  site.  "Striking  the  funny  bone"  is 
the  paresthesia  elicited  from  the  ulnar  nerve  at  the  elbow.  The 
pain  is  usually  brief  and  may  be  followed  by  a  sensation  of 
warmth  or  numbness  in  the  area  of  previous  radiation.  A  pares- 
thesia does  not  indicate  that  permanent  or  serious  nerve  in- 
jury has  occurred,  it  simply  indicates  that  the  needle  is  very 
close  to  or  touching  the  nerve.  When  one  performs  major  nerve 
blocks,  paresthesias  are  sought  and  used  as  a  method  of  iden- 
tifying the  appropriate  site  for  injection.  The  consequences 
of  transient  paresthesias  are  minimal. 

If  a  paresthesia  is  obtained  during  arterial  localization 
for  sampling,  the  seeking  needle  should  be  withdrawn.  The 
paresthesia  should  immediately  disappear.  Persistent  pares- 
thesias after  needle  withdrawal  or  other  neurologic  find- 
ings may  be  cause  for  concern.  These  usually  indicate  that 
nerve  injury  has  occurred  and  follow-up  examinations  are 
needed.  Nerve  conduction  studies  performed  several  weeks 
later  can  identify  the  location  and  extent  of  a  peripheral 
nerve  injury. 

Peripheral  nerve  injuries  are  treated  in  several  ways.  Minor 
injuries  (such  as  those  from  a  small  needle)  usually  resolve 
with  no  specific  treatment.  Physical  therapy  to  prevent  the 
complications  from  nonuse  of  the  extremity  may  be  bene- 
ficial. Axons  grow  approximately  0.5-1 .0  mm/day  and  rein- 
nervation  will  occur  if  the  nerve  bundle  is  intact.  If  the  nerve 
is  severed,  surgical  repair  or  an  interposed  graft  may  be  nec- 
essary. This  type  of  injury  occurs  during  penetrating,  sharp 
(knife  or  glass)  trauma  and  is  unlikely  in  a  needle  injury. 
Hematoma  formation  may  injure  the  nerve  by  pressure  (is- 
chemic) necrosis.  This  injury  may  require  release  of  pres- 
sure by  drainage  of  the  hematoma  to  improve  neurologic  func- 
tion. There  is  a  window  of  2-12  hours  when  this  type  of  in- 
jury is  potentially  reversible. 

Occasionally,  minor  trauma  to  an  extremity  can  lead  to  se- 
vere neurologic  symptoms.  The  development  of  reflex  sym- 
pathetic dystrophy  or  causalgia  are  devastating  complications 
believed  to  be  caused  by  sympathetic-nervous-system-me- 
diated peripheral  nerve  sensitization. u  Symptoms  include  burn- 
ing pain,  vasoconstriction,  reduced  blood  flow,  and  atroph- 


1118 


respiratory  Care  •  November  '95  vol  40  no 


Editorial 


ic  changes.  These  are  not  in  typical  dermatome  location.  Sig- 
nificant functional  loss  is  often  present.  The  syndrome  develops 
over  several  weeks  to  months.  There  may  be  an  antecedent 
identifiable  injury  (causalgia)  or  not  (reflex  sympathetic  dys- 
trophy). Some  of  the  features  of  the  reported  case  are  con- 
sistent with  causalgia.  Treatment  is  early  intervention  with 
sympathetic  nervous  system  interruption.  Repeated  sympa- 
thetic nerve  blocks  with  local  anesthetics  can  help  prevent  pro- 
gression of  the  condition.  Prolonged  and  intensive  physical 
therapy  may  be  necessary  in  severe  cases.  Sympathetic-ner- 
vous-system-mediated pain  may  have  been  a  problem  in  the 
case  reported. 

Patient  injuries  may  not  be  entirely  preventable.  The 
medicolegal  consequences  of  an  adverse  outcome  are  reduced 
when  the  practitioner  is  aware  of  a  potential  problem  and  takes 
care  to  avoid  it.  Performing  only  necessary  treatments  in  the 
safest  possible  way  is  essential.  Understanding  what  can  hap- 


pen and  how  to  avoid  it  is  the  responsibility  of  the  person  doing 
the  procedure. 

Charles  G  Durbin  Jr  MD 

Professor  of  Anesthesiology  &  Surgery 

Medical  Director,  Respiratory  Care  Services 

The  University  of  Virginia  Health  Sciences  Center 

Charlottesville.  Virginia 


REFERENCES 

Watson  ME.  Median  nerve  damage  from  brachial  artery  puncture: 
a  case  report.  Respir  Care  1995:40(  1 1):  1 141-1 143. 
Hord  AH.  Chaet  M.  Fleming  LL.  Current  treatment  of  reflex  sym- 
pathetic dystrophy.  Perspect  Orthop  Surg  1990;1:81-101. 
Bonica  JJ.  Causalgia  and  other  reflex  sympathetic  dystrophies.  Post- 
grad Med  1973;53(6):143-148. 


4f 


41st  Annual  Convention  and  Exhibition 
December  2-5  •  Orlando,  Florida 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1119 


Original  Contributions 


Octave  Waveband  Analysis  To  Determine  Sound  Frequencies  and 
Intensities  Produced  by  Nebulizers  and  Humidifiers  Used  with  Hoods 

Shelley  C  Mishoe  PhD  RRT,  C  Worth  Brooks  Jr  MEd  RRT, 
Franklin  H  Dennison  MEd  RRT  RPFT,  Kim  Valeri  Hill  MSEd  RRT,  and  Thomas  Frye  BS  RRT 


BACKGROUND:  Health-care  practitioners  should  be  aware  of  how  their  equip- 
ment and  practices  can  increase  the  patient's  risk  for  noise-induced  hearing 
loss.  PURPOSE:  We  conducted  this  study  to  determine  the  type  of  noise  pro- 
duced by  humidifiers  and  nebulizers  used  with  hoods  in  the  neonatal  inten- 
sive care  unit  (NICU).  We  performed  octave  waveband  analysis  to  determine 
sound  intensities  and  frequencies  because  degree  of  hearing  loss  from  noise 
exposure  is  related  to  the  intensity  of  sound,  frequency  of  sound,  and  dura- 
tion of  exposure.  METHODS:  We  studied  4  simple  humidifiers,  3  heated  hu- 
midifiers, and  4  nebulizers.  Sound  levels  were  measured  at  various  frequencies, 
flows,  and  water  levels  using  Peace  and  Shiley  oxygen  hoods.  RESULTS:  The 
findings  show  that  sound  levels  were  significantly  louder  (p  <  0.001 )  for  neb- 
ulizers compared  to  humidifiers.  Aquapak  nebulizers  pose  the  greatest  risk 
for  hearing  loss  because  they  produce  sound  at  the  highest  frequencies  and 
volume.  The  peak  sound  levels  of  humidifiers  not  only  were  significantly  lower 
but  also  occurred  at  the  lowest  sound  frequencies,  which  are  the  least  dam- 
aging to  hearing.  Sound  levels  were  generally  higher  across  sound  frequen- 
cies at  higher  flows  and  with  the  Peace  Hood.  CONCLUSION:  We  conclude 
that  heated  humidifiers  produce  lowest  sound  intensities  at  the  lowest  sound 
frequencies  and,  consequently,  are  most  appropriate  for  use  in  the  NICU.  [Respir 
Care  1995;40(1 1):1 120-1 124] 


Background 

Although  little  is  known  about  the  epidemiology  of  hear- 
ing loss  in  children.1  studies  have  demonstrated  that  prolonged 


Dr  Mishoe  is  Associate  Professor  and  Chair,  Mr  Brooks  is  Assistant  Pro- 
fessor  and  Director  of  Admissions,  Mr  Dennison  is  Assistant  Professor, 
and  Mr  Frye  is  Instructor— Department  of  Respirators  Therapy.  Medical 
College  of  Georgia.  Augusta.  Georgia.  Ms  Hill  is  Instructor,  Department 
of  Respiratory  Therapy,  Sinclair  Community  College.  Dayton.  Ohio. 

A  version  ol  tins  paper  was  presented  during  the  RESPIRATORY  CARL 
i  >PI  N  I  i  IRI  M  ai  the  AARC  Annual  Meeting  held  in  San  Antonio.  Texas, 
December  12-15,  1992. 

None  ol  the  authors  lias  a  financial  interest  m  any  ol  the  products  men 
tinned  in  this  papei 

Reprints  Shellej  C  Mishoe  PhD  RRT.  Department  ol  Respiratory  Ther- 
apy. HM-143,  Medical  College  ol  Georgia,  Augusta GA  30912-0850, 


neonatal  illness  and  its  management  are  related  to  sensori- 
neural healing  loss  in  preterm  infants.2,3  Up  to  9%  oflow- 
birthweight  infants  who  require  extended  hospitalization  at 
birth  have  been  found  to  have  some  degree  of  hearing  loss,4 
compared  to  a  2%  incidence  among  all  newborns.5  Salamy 
et  al:  and  Halpem  et  al3  have  shown  that  the  length  of  hospi- 
talization in  the  neonatal  intensive  care  unit  (NICU)  and  du- 
ration of  assisted  ventilation  (among  other  variables)  contri- 
bute to  sensorineural  hearing  loss. 

One  factor  related  to  prolonged  hospitalization  that  can  be 
hazardous  to  hearing  is  the  noise  in  the  NICU  caused  by  me- 
chanical equipment.6 "'  The  purpose  of  our  study  was  to  de- 
termine how  respiratory  care  equipment  used  for  humidifi- 
cation  and  oxygenation  contributes  to  noise  level  in  the  NICU. 
Noise  levels  in  the  hospital  environment  have  increased  with 
the  use  of  technology  and  often  exceed  safe  or  comfortable 
levels.8,10,11  Reducing  noise  exposure  in  the  NICU  is  an  im- 


1120 


Rj  spiratory  Care  •  November  '95  vol  40  No  1 1 


Noise  Produced  by  Nebulizers  &  Humidifiers 


portant  consideration  not  only  in  the  prevention  of  hearing 
impairment  but  also  for  alleviating  stress12  and  sensory  over- 
load11 in  preterm  infants. 

Hearing  loss  resulting  from  noise  exposure  is  related  to 
intensity  of  sound  (reported  in  decibels,  ordB);  frequency  of 
sound  (reported  in  hertz,  or  Hz);  and.  duration  of  noise  ex- 
posure. Sound  intensity  or  sound  level  determines  how  loud 
a  noise  is  perceived;  whereas,  sound  frequency  determines 
the  pitch.  For  example,  the  frequency  of  a  locomotive  horn 
is  approximately  250  Hz,  and  the  frequency  of  a  table  saw 
is  4.000  Hz.14  One  Hz  equals  60  cycles/s.  The  human  ear  is 
sensitive  to  a  frequency  range  of  20  to  20,000  Hz.15 

Sound  intensity  is  measured  in  decibels,  a  decibel  being 
defined  as  10  times  the  intensity-level  logarithm.  Because 
the  human  ear  is  more  sensitive  to  the  damaging  effects  of 
high-frequency  sound  than  to  low-frequency  sound,  a  bet- 
ter correlation  with  noise-induced  hearing  loss  is  obtained 
when  low-frequency  sound  is  filtered  out  using  the  A-weight- 
ed  scale. Ifl  This  means  that  a  sound  of  90  decibels  on  the  A- 
weighted  scale  (dBA)  is  ten  times  stronger  than  a  sound  of 
80  decibels,  and  the  sound  of  100  decibels  is  100  times 
stronger  than  a  sound  of  80  decibels.  A  conversational  voice 
is  around  65  dBA;  a  shout  is  90  dBA  or  louder.14  Therefore, 
it  is  conventionally  agreed  that  the  A-weighted  scale  is  the 
best  single-number  estimate  of  the  probable  effects  of  sound 
on  human  ears.  However,  broad-spectrum  analysis,  commonly 
called  octave-waveband  analysis,  is  most  desirable  for  de- 
termining both  the  sound  frequency  and  the  sound  intensi- 
ty. The  human  ear  is  more  sensitive  to  the  damaging  effects 
of  high-frequency  sound  (>  4,000  Hz)"1  and  infants  are  more 
sensitive  than  adults.17  Consequently,  mechanical  equipment 
that  produces  sound  at  high  frequencies  and  high  intensities 
is  potentially  most  damaging  to  infants'  hearing. 

Infants  are  susceptible  to  sensorineural  hearing  loss  be- 
cause of  the  immaturity  of  the  developing  organ  of  Corti  and 
numerous  risk  factors  as  shown  in  Table  l.18  Experimen- 
tal and  clinical  evidence  have  demonstrated  the  damaging 
effects  on  the  cochlea  of  noise  exposure  in  combination  with 
ototoxic  antibiotics.1,18,19"23  Light  microscopy  shows  that  the 
damage  caused  by  the  combination  of  noise  and  ototoxic  an- 
tibiotics is  characterized  by  degeneration  of  the  sensory  cells 
of  the  organ  of  Corti.20"22  It  has  been  shown  in  animal  stud- 
ies that  the  cellular  damage  to  the  organ  of  Corti  after  com- 
bined exposure  to  noise  and  antibiotics  exceeds  the  sum  of 
the  separate  effects  of  each  agent. K:l  In  a  study  of  1,240 
infants.  Smith  et  al23  identified  the  use  of  ototoxic  antibi- 
otics and  gestational  age  less  than  36  weeks  as  important 
risk  factors  for  hearing  loss  detected  by  auditory  brain-stem 
response  (ABR)  screening  failures.  The  level  and  type  of 
noise  exposure  in  the  NICU  should  be  of  particular  concern 
to  health-care  professionals  because  premature  babies  are 
even  more  susceptible  than  full-term  babies  to  noise-induced 
hearing  damage  and  often  are  given  ototoxic  antibiotics  to 
combat  sepsis. 


Table  I .      Risk  Factors  for  Sensorineural  Hearing  Impairment  in 
Neonates 

•  Family  history  of  congenital  or  childhood  hearing  sensorineural  im- 
pairment 

•  Congenital  infection  (toxoplasmosis,  syphilis,  rubella, 
cytomegalovirus,  herpes) 

•  Craniofacial  anomalies 

•  Birthweight  <  1500  g  «  3.3  lb) 

•  Hyperbilirubinemia  at  a  level  exceeding  indication  for  exchange 
transfusion 

•  Ototoxic  medications  (aminoglycosides,  loop  diuretics) 

•  Bacterial  meningitis/sepsis 
■      Severe  depression  at  birth 

•  Prolonged  mechanical  ventilation  >  10  days 

Underlying  clinical  condition  (hyperbilirubinemia,  apnea,  hypoxia, 
hypertension,  renal  impairment) 

•  Stigmata  or  other  syndromes  associated  with  sensorineural  hearing 
loss 


Adapted  from  Reference  18.  with  perrni- 


Methods  &  Materials 

We  performed  octave  waveband  analysis  by  measuring 
sound  intensities  produced  by  the  equipment*  at  specific  fre- 
quencies. Sound  levels  (dB)  were  measured  with  a  sound-level 
meter  at  frequencies  of  250. 500,  1 ,000, 2,000, 4,000,  and  8,000 
Hz.  The  measurements  were  taken  inside  an  oxygen  hood  with- 
in a  closed  incubator  with  the  motor  off. 

Background  noise  level  was  maintained  constant  at  45 
dBA — an  increase  from  our  earlier  work  in  which  we  used  a 
background  noise  level  of  40  dBA.24  This  change  is  based  on 
our  own  measurements  in  our  NICU  and  the  reports  of  oth- 
ers25-26 that  have  been  published  in  the  interim. 

We  studied  4  simple  humidifiers:  Aquapak  302,  Dart  325 
mL,  MistyOx  500  niL,  and  Travenol;  3  heated  humidifiers: 
Conchafherm  III,  Fisher  &  Paykel  MR  630,  and  the  Marquest 
SCT  2000;  and  5  nebulizers:  Aquapak  ( AP)  700  mL  and  1,000 
mL,  Dart  300  mL,  MistyOx  500  mL,  and  Travenol  1 .000  mL. 
We  randomly  selected  5  of  each  for  study.  We  chose  the  equip- 
ment because  it  was  commonly  used  in  NICUs  in  the  sur- 
rounding 3-state  area.  We  studied  the  equipment  at  oxygen 
flows  of  6,  8,  10,  and  12  L/min  under  full,  half-full,  and  empty 
water-reservoir  conditions,  using  both  the  Shiley  and  Peace 
Hoods.  Nebulizers  were  tested  at  fractional  concentration  of 
delivered  oxygen  (Foo:)  of  1 .0.  Equipment  was  set  up  according 
to  manufacturers'  guidelines. 

Sound  levels  were  analyzed  using  repeated  measures  anal- 
ysis of  variance  (ANOVA).  A  p  value  <  0.05  indicated  sta- 
tistical significance.  Tukey's  HSD  was  performed  post-hoc 
on  all  significant  ANOVAs  to  make  pairwise  comparisons. 


*  Suppliers  are  identified  in  the  Product  Sources  section  at  the  end  of 
the  text. 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


121 


Noise  Produced  by  Nebulizers  &  Humidifiers 


Results 

Sound  levels  were  significantly  louder  for  nebulizers  (mean 
|SD]  62  [9]  dB)  compared  to  humidifiers  (48  [3]  dB)  as  shown 
in  Figure  1  (p  <  0.001 ).  Type  of  equipment  had  a  significant 
main  effect  on  sound  levels  at  all  frequencies,  except  2,000 
Hz,  and  explained  almost  40%  of  the  variance  in  sound  lev- 
els (R:  =  0.381;  p  <  0.01).  Mean  sound  intensities  at  each 
sound  frequency  for  nebulizers  and  humidifiers  are  shown 
in  Tables  2  and  3. 


1000      2000      4000      8000 


Sound  Frequency  (Hz) 


Fig.  1 .  Sound  intensities  of  nebulizers  (■)  and  humidifiers  (      )  at 
each  sound  frequency  tested.  Bars  are  mean  +  standard  deviation. 


Nebulizers  produced  maximum  sound  levels  (55  [  14]  dB) 
at  higher  frequencies  of  4,000  Hz.  At  8.000  Hz.  there  was 
a  significant  main  effect  for  hoods  when  nebulizers  were 
used  (p  <  0.001 ).  Sound  levels  were  significantly  louder  when 
using  the  Peace  Hood  (15  [18]  dB)  versus  the  Shiley  Hood 
(9  [15]  dB).  At  the  lower  frequencies,  <  1 ,000  Hz,  the  hood 


type  did  not  affect  sound  levels.  There  was  a  2-way  inter- 
action for  nebulizer  and  flow  at  1 .000  Hz  (p  <  0.001 ),  2,000 
Hz  (p  <  0.01 ),  4,000  Hz  (p  <  0.001 )  and  8,000  Hz  (p  <  0.001 ). 
Flow  and  hood  type  did  not  affect  sound  levels  at  frequencies 
of  250  and  500  Hz.  A  significant  main  effect  for  water  level 
was  observed  at  all  frequencies  (p  <  0.001 ),  except  250  Hz. 
For  example,  sound  levels  increased  from  23  [19]  dB  when 
full  to  30  [21]  dB  when  dry.  Sound  levels  were  significantly 
louder  under  conditions  of  low  water  levels  and  high  flows. 
At  4,000  Hz,  sound  levels  increased  from  39  [21]  dB  at  6 
L/minto58  [20]  dB  at  12L/min. 

Aquapak  700  mL  and  1 .000  mL  nebulizers  were  the  loud- 
est and  also  produced  sound  at  higher  frequencies.  The  700 
mL  model  had  a  peak  sound  level  of  69  [5]  dB  and  the  1 .000 
mL  model  had  a  peak  sound  level  of  59  [6]  dB,  at  4,000  Hz. 
The  Travenol  nebulizers  also  produced  peak  sound  intensi- 
ties at  the  highest  frequencies  (53  [6]  dB).  The  Dart  and  Misty- 
Ox  nebulizers  were  the  quietest  and  produced  sound  at  the  low- 
est frequency  (Table  2). 

Table  2.      Mean  (SD)  Sound  Intensities  (dB)  of  Nebulizers  at  Various 
Frequencies 


Frequency 
(Hz) 


Travenol        Dart        MistvOx    AP  1,000     AP  700 


250 

23(19) 

51(13) 

53   (2) 

51(13) 

23 ( 1  1 ) 

500 

19(24) 

39   (7) 

42    (6) 

55(21) 

7(17) 

1,000 

19(17) 

40(10) 

40(16) 

58(20) 

12(15) 

2.000 

16(23) 

29(16) 

20(20) 

47(17) 

6(14) 

4.000 

53   (7) 

46(12) 

40    (8) 

59    (6) 

69    (5) 

8,000 

15(15) 

24(17) 

16(15) 

43(17) 

5(13) 

Maximum  sound  levels  of  humidifiers  occurred  at  250  Hz 
(51  [2]  dB)  and  lessened  significantly  above  1,000  Hz.  A  3- 
way  interaction  occurred  among  humidifiers,  hoods,  and  water 
levels  at  250  and  500  Hz  and  among  humidifiers,  hoods  and 
flows  at  2,000  Hz  (p  <  0.01 ).  There  were  2-way  interactions 
between  humidifier  and  flow  (p  <  0.001 )  and  between  hu- 
midifier and  hood  (p  <  0.0 1 )  at  1 ,000,  2,000,  and  4.000  Hz. 
However,  at  these  frequencies  sound  levels  were  generally 
louder  when  the  Peace  Hood  was  used  and  when  higher  Hows 


Table  3.      Mean  (SD)  Sound  Intensities  (dB)  of  Humidifiers  at  Various  Frequencii 


Frequency 

(Hz) 

Conchatherm* 

Fisher-Paykel* 

Marquest* 

Travenol 

Dart 

MistvOx 

Aquapak 

250 

50   (3) 

51    (3) 

54    (1) 

53    (2) 

50    (3) 

50   (3) 

49    (3) 

500 

39    (3) 

38    (3) 

36  (2) 

39   (4) 

36   (3i 

41    (3) 

35    (5) 

1.000 

12(12) 

7(10) 

0 

32    (8) 

34    (7) 

35    (8) 

27(16) 

2.000 

6(10) 

0 

0 

24(221 

24(24) 

24(21) 

21(23) 

4.000 

1) 

0 

0 

14(14) 

14(14) 

14(14) 

16(15) 

8,000 

0 

0 

0 

13(15) 

21(14) 

13(14) 

8(15) 

*  Heated  humidifiers 

1122 


Respiratory  Care  •  November  '95  vol  40  No 


Noise  Produced  by  Nebulizers  &  Humidifiers 


were  used.  For  example,  at  2,000  Hz  the  sound  levels  were 
negligible  when  using  the  Shiley  Hood  (2  [5]  dB),  but  were 
significantly  higher  when  the  Peace  Hood  was  used  (27  [21] 
dB ;  p  <  0.00 1 ).  At  8.000  Hz,  the  sound  intensities  were  sig- 
nificantly higher  when  using  the  Peace  Hood  ( 10  [  15]  dB)  com- 
pared to  the  Shiley  Hood  (6  [1  l]dB]:  p  <  0.001 ). 

As  shown  in  Table  3,  the  3  heated  humidifiers  did  not  pro- 
duce sound  at  the  higher  frequency  levels  and  were  the  qui- 
etest. Unlike  the  heated  humidifiers,  the  simple  humidifiers 
produced  sound  at  all  frequencies.  The  Travenol  and  Dart 
Humidifiers  were  the  loudest  of  the  humidifiers  we  tested 
(Table  3). 

Discussion 

Octave  waveband  analysis  provides  useful  information  to 
allow  rational  selection  of  respiratory  care  equipment  for  use 
in  the  NICU  environment.24-2728  Our  data  indicate  that  the  use 
of  nebulizers  and  humidifiers  with  hoods  contributes  to  in- 
creased noise  exposure  for  infants  in  the  NICU.  Sound  lev- 
els recorded  in  this  study  were  of  sufficient  intensity  and  fre- 
quency to  interfere  with  sleep  and,  possibly,  to  damage  hear- 
ing of  infants,  especially  when  antibiotics  are  used.19-21-29 

The  nebulizers  produced  noise  of  higher  sound  intensity 
and  higher  sound  frequency,  which  poses  increased  risk  for 
noise-induced  hearing  loss.  Our  results  support  the  findings 
of  other  investigators  who  also  reported  that  the  Aquapak  neb- 
ulizers were  the  loudest  under  various  testing  conditions.30-31 
Not  only  were  the  Aquapak  700  and  1.000  mL  nebulizers  the 
loudest,  but  the  data  demonstrate  that  the  greatest  sound  is  pro- 
duced at  the  highest  frequencies.  Broadband  noise  generation 
resulting  in  high-frequency  sound  has  been  demonstrated  to 
be  more  upsetting  and  damaging  than  low-frequency  sound.15 17 
Authors  have  speculated  that  the  nebulizer  sound  spectrum  de- 
termined by  octave  waveband  analysis  is  as  important  as  deci- 
bel measurements  to  explain  why  some  equipment  is  perceived 
as  louder  or  noisier,  even  though  there  are  no  differences  in 
measurements  using  the  A-weighted  scale.24-3"  The  results  of 
this  study  suggest  that  nebulizers  should  not  be  used  in  the  NICU 
because  they  produce  more  noise  across  all  sound  frequencies. 
High-intensity  sound  at  high  frequencies,  as  produced  by  neb- 
ulizers, is  potentially  most  damaging  to  infant  hearing. 

Sound  levels  were  significantly  louder  with  nebulizers  as 
compared  to  humidifiers,  particularly  at  high  frequencies.  Our 
previous  research24  and  a  related  study28  demonstrated  under 
various  testing  conditions  that  all  of  the  humidifiers  produced 
sound  levels  <  58  dBA.  the  maximum  recommended  by  the 
American  Academy  of  Pediatrics,15  but  the  nebulizers  exceeded 
this  level  (Table  2).  Therefore,  humidifiers  are  most  appro- 
priate for  use  in  the  NICU. 

The  heated  humidifiers  produced  the  lowest  sound  intensities 
at  the  lowest  frequencies.  Furthermore,  broad-spectrum  analy- 
sis demonstrated  that  the  heated  humidifiers  do  not  produce 
sound  at  high  frequencies.  Therefore,  we  recommend  that  heat- 


ed humidifiers  be  used,  whenever  possible  in  NICU,  as  one 
means  of  decreasing  infants'  exposure  to  high-frequency  and 
high-intensity  sound.  Noise-induced  hearing  loss  can  be  min- 
imized in  the  NICU  by  eliminating  this  type  of  sound. 

The  results  of  this  study  and  other  studies2431  indicate  that 
the  hood  itself  can  significantly  affect  sound  intensity  and  should 
be  a  consideration  in  noise  reduction.  Although  we  had  3-way 
and  2-way  interactions  that  prohibit  further  discussion  of  main 
effects  across  frequencies,  we  found  that  the  sound  intensi- 
ties were  generally  lower  for  nebulizers  and  humidifiers  when 
the  Shiley  hood  was  used.  However,  hood  type  did  not  affect 
sound  levels  for  nebulizers  at  frequencies  of  250  and  500  Hz 
or  for  humidifiers  at  frequencies  <  1 ,000  Hz.  The  hood  type 
had  a  significant  effect  on  noise  produced  by  both  nebuliz- 
ers and  humidifiers  at  the  highest  frequency  of  8,000  Hz.  Sound 
levels  were  significantly  lower  when  the  Shiley  Hood  was  used. 
The  Shiley  hood  utilizes  a  foam  insert  at  the  oxygen  tubing 
inlet  port,  which  the  manufacturer  described  as  a  water  and 
noise  filter.  The  filter  may  explain  differences  in  noise  lev- 
els between  the  two  hood  designs.  The  Shiley  hood  that  we 
tested  is  no  longer  marketed.  However,  we  recommend  the 
use  of  hoods  that  incorporate  noise  reduction  features. 

Water  levels  significantly  affected  the  sound  levels  of  neb- 
ulizers at  all  frequencies  except  250  Hz,  but  water  levels  did 
not  significantly  affect  the  sound  levels  of  humidifiers.  Sound 
levels  for  nebulizers  were  louder  at  lower  water  levels.  Al- 
though we  do  not  recommend  the  use  of  nebulizers  in  the 
NICU,  if  nebulizers  are  used,  attention  should  be  given  to 
maintaining  full  water  reservoirs.  Based  on  this  study,  our 
previous  study,24  and  our  related  study,28  we  also  recommend 
that  the  lowest  possible  flows  be  used  whenever  possible 
because  this  may  also  be  a  factor  in  reducing  infants'  ex- 
posure to  noise  in  the  NICU. 

Although  an  incubator  was  utilized  in  our  study,  we  did 
not  specifically  evaluate  the  effects  of  incubator  noise.  How- 
ever, a  few  studies  over  the  past  2  decades  have  reported  ex- 
cessive noise  exposure  for  infants  kept  in  incubators. 7-8-19-32'34 
Manufacturers  should  explore  ways  to  modify  equipment  used 
in  neonatal  and  pediatric  care — reducing  noise  levels  with- 
out increasing  cost.  Additional  research  is  needed  on  the  syn- 
ergistic effects  of  noise  created  by  other  factors  in  the  NICU 
such  as  incubators,  monitors,  ventilators,  alarms,  and  person- 
nel activities  such  as  conversation,  opening  incubator  doors, 
and  using  radios  at  the  bedside.  Health-care  professionals 
should  actively  pursue  measures  to  monitor  noise  levels  and 
minimize  noise  exposure  of  all  patients,  particularly  infants. 


PRODUCT  SOURCES 


Simple  Humidifiers: 

Aquapak  301,  Respiratory  Care  Inc.  Arlington  Heights  IL 
Dart  325  mL.  Dart  Respiratory.  Seamless  Professional  Medical  Prod- 
ucts Inc,  Ocala  FL 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1123 


Noise  Produced  by  Nebulizers  &  Humidifiers 


MistyOx  500  mL,  Medical  Molding  Corp  of  America,  Respiratory  Med- 
ical Products  Division,  Costa  Mesa  CA 
Travenol,  Travenol  Laboratories  Inc.  Deerfield  IL 

Heated  Humidifiers: 

Conchatherm  III.  Hudson  Respiratory  Care  Inc.  Temecula  CA 
Fisher  &  Paykel  MR  630.  Fisher  &  Paykel  LTD  Medical  Division,  New 

Zealand 
Marquest  SCT  2000,  Marquest  Medical  Products  Inc.  Englewood  CO 

Nebulizers: 

Aquapak  700  mL  and  1,000  mL,  Respiratory  Care  Inc.  Arlington 
Heights  IL 

Dart  300  mL,  Dart  Respiratory,  Seamless  Professional  Medical  Prod- 
ucts Inc.  Ocala  FL 

MistyOx  500  mL,  Medical  Molding  Corp  of  America,  Respiratory  Med- 
ical Products  Division,  Costa  Mesa  CA 

Travenol  1000  mL,  Travenol  Laboratories  Inc.  Deerfield  IL 

Incubator: 

Isolette  Infant  Incubator,  Air-Shields  Inc.  A  Narco  Health  Company,  Hat- 
boro  PA 

Sound  Level  Meter: 

Tracor  RA1 10,  Tremetrics  Inc,  Austin  TX 


REFERENCES 

1 .  Todd  NW.  At-risk  populations  for  hearing  impairment  in  infants  and 
young  children.  Int  J  Pediatr  Otorhinolaryngol  1994;29(1):1 1-21. 

2.  Salamy  A,  Eldredge  L,  Tooley  WH.  Neonatal  status  and  hearing  loss 
in  high  risk  infants.  J  Pediatr  1989;1 14(5):847-852. 

3.  Halpern  J,  Hosford-Dunn  H,  Malachowski  N.  Four  factors  that  ac- 
curately predict  hearing  loss  in  'high  risk'  neonates.  Ear  Hear  1987;8 
(l):21-25. 

4.  Bergman  I,  Hirsch  RP,  Fria  TJ,  Shapiro  SM,  Holzman  I,  Painter  MJ. 
Cause  of  hearing  loss  in  the  high-risk  premature  infant.  J  Pediatr 
1985;106(1):95-101. 

5.  Thiringer  K,  Kankkunen  A,  Liden  G.  Niklasson  A.  Perinatal  risk  fac- 
tors in  the  aetiology  of  hearing  loss  in  preschool  children.  Dev  Med 
Child  Neurol  1984;26(6):799-807. 

6.  Anagnostakis  D,  Petmezakis  J,  Papazissis  G,  Messaritakis  J,  Mat- 
saniotis  N.  Hearing  loss  in  low-birth-weight  infants.  Am  J  Dis  Child 
1982;136(7):602-604. 

7.  Thomas  KA.  How  the  NICU  environment  sounds  to  a  preterm  in- 
fant. MCN  Am  J  Matern  Child  Nurs  1989;14(4):249-251. 

8.  Bess  FH,  Peek  BF,  Chapman  JJ.  Further  observations  on  noise  lev- 
els in  infant  incubators.  Pediatrics  1979;63(1):100-106. 

9.  Minoli  I,  Moro  G.  Constraints  of  intensive  care  units  and  follow-up 
studies  in  prematures.  Acta  Otolaryngol  Stockh  1985;421(Suppl): 
62-67. 

10.  Balogh  D,  Kittinger  E,  Benzer  A,  Hackl  JM.  Noise  in  the  ICU.  In- 
tensive Care  Med  1993;19(6):343-346. 

1 1 .  Gottfried  AW,  Hodgman  JE.  How  intensive  is  newborn  intensive  care? 
An  environmental  analysis.  Pediatrics  1984;74(2):292-294. 


12.  Field  T.  Alleviating  stress  in  newborn  infants  in  the  intensive  care 
units.  Clin  Perinatol  1 990;  1 7(  1 ):  1  -9. 

1 3.  Baker  CF.  Sensory  overload  and  noise  in  the  ICU:  sources  of  en- 
vironmental stress.  Crit  Care  Q  1984;6:66-80. 

14.  Hearing  conservation:  A  guide  to  preventing  hearing  loss.  Daly  City 
CA:  Krames  Communications,  1985. 

15.  American  Academy  of  Pediatrics  Committee  on  Environmental 
Hazards.  Noise  pollution:  neonatal  aspects.  Pediatrics  1974;54(4): 
476-479. 

1 6.  Heffler  AJ.  Hearing  loss  due  to  noise  exposure.  Otolaryngol  Clin  North 
Am  1978;ll(3):723-740. 

17.  Price  GR.  Age  as  a  factor  in  susceptibility  to  hearing  loss:  young  ver- 
sus adult  ears.  J  Acoust  Soc  Am  1976;60(4):886-892. 

1 8.  Joint  Committee  on  Infant  Hearing.  1 990  position  statement.  ASHA 
1991;March(5,  Suppl):3-6. 

1 9.  Falk  S A,  Woods  NF.  Hospital  noise-levels  and  potential  health  haz- 
ards. N  Engl  J  Med  1973;289(15):774-780. 

20.  Falk  S  A,  Farmer  JC  Jr.  Incubator  noise  and  possible  deafness.  Arch 
Otolaryngol  1973;97(5):385-387. 

2 1 .  Jauhiainen  T,  Kohonen  A,  Jauhiainen  M.  Combined  effects  of  noise 
and  neomycin  on  the  cochlea.  Acta  Otolaryngol  Stockh  1972;73 
(5):387-390. 

22.  Dayal  VS,  Kokshanian  A,  Mitchell  DP.  Combined  effects  of  noise 
and  kanamycin.  Ann  Otol  Rhinol  Laryngol  1971;80(6):897-901. 

23.  Smith  RJ,  Zimmerman  B,  Connolly  PK,  Jerger  SW,  Yelich  A.  Screen- 
ing audiometry  using  the  high-risk  register  in  a  level  III  nursery.  Arch 
Otolaryngol  Head  Neck  Surg  1 992;  1 1 8(  1 2):  1 306- 1311. 

24.  Beckham  RW,  Mishoe  SC.  Sound  levels  inside  incubators  and  oxy- 
gen hoods  used  with  nebulizers  and  humidifiers.  Respir  Care  1982; 
27(l):33-40. 

25.  Richmond  KH.  Konkle  DF,  Potsic  WP.  ABR  Screening  of  high-risk 
infants:  effects  of  ambient  noise  in  the  neonatal  nursery.  Otolaryn- 
gol Head  Neck  Surg  1986;94(5):552-560. 

26.  Aitken,  RJ.  Quantitative  noise  analysis  in  a  modem  hospital.  Arch 
Environ  Health  1982;37(6):361-364. 

27.  Mishoe  SC,  Brooks  CW  Jr,  Valeri  KL.  Octave  band  analysis  of  sound 
level  frequencies  and  intensities  produced  by  nebulizers  and  humidifiers 
(abstract).  Respir  Care  1992;37(  1 1 ):  1 288- 1 289. 

28.  Mishoe  SC,  Brooks  CW,  Valeri  KL,  Taft  AA.  Sound  levels  of  hu- 
midifiers and  nebulizers  supplying  oxygen  hoods  (abstract).  Respir 
Care  1992;37(1 1):1288. 

29.  Topf  M,  Davis  JE.  Critical  care  unit  noise  and  rapid  eye  movement 
(REM)  sleep.  Heart  Lung  1993;22(3):252-258. 

30.  Clark  B,  Nash  L,  Jackson  D,  Parker  M,  Gradwell  G.  Sound  level  com- 
parison between  UHC-qualified-prefilled  nebulizers  (abstract).  Respir 
Care  1992:37(1 1):  1298. 

3 1 .  Smith  J.  Mathews  PJ.  What  factors  influence  noise  levels  inside  oxy- 
gen hoods?  (abstract).  Respir  Care  199 1  ;36(  1 1 ):  1 306. 

32.  Douek  E,  Dodson  HC,  Bannister  LH,  Ashcroft  P,  Humphries  KN. 
Effects  of  incubator  noise  on  the  cochlea  of  the  newborn.  Lancet 
1976;2(7995):  11 10-1 113. 

33.  Blennow  G,  Svenningsen  NW,  Almquist  B.  Noise  levels  in  infants' 
incubators  (adverse  effects?).  Pediatrics  1974:53(l):29-32. 

34.  Long  JG,  Lucey  JF,  Philip  AG.  Noise  and  hypoxemia  in  the  inten- 
sive care  nursery.  Pediatrics  1980:65(  1 ):  143- 145. 


124 


RESPIRATORY  CARE  •  NOVEMBER  '95  VOL  40  NO  1 1 


The  Impact  of  a  Postoperative  Oxygen  Therapy  Protocol  on 
Use  of  Pulse  Oximetry  and  Oxygen  Therapy 

JJ  Komara  Jr  RRT  and  James  K  Stoller  MD 


BACKGROUND:  Recent  evidence  suggests  that  both  pulse  oximetry  mon- 
itoring and  oxygen  (O2)  therapy  may  be  used  inappropriately  at  times,  im- 
plying the  need  for  improved  use  of  pulse  oximetry  by  health-care  providers. 
METHODS:  We  studied  the  clinical  and  financial  impact  of  a  postoperative 
02-therapy  protocol  in  2  groups  of  patients.  Group  1  (n  =  20)  was  comprised 
of  patients  whose  physicians  made  all  O2  therapy  management  decisions.  Group 
2  (n  =  20)  was  comprised  of  patients  whose  O2  therapy  management  was  per- 
formed by  respiratory  therapists  according  to  an  algorithm  with  a  stop  cri- 
terion of  Spo2  ^92%.  The  duration  of  postoperative  O2  therapy,  the  frequency 
of  unnecessary  O2  therapy,  and  group  totals  of  Spo2  measurements  were  com- 
pared between  groups  using  the  Mann- Whitney  Rank  Sum  Test.  RESULTS: 
O2  therapy  was  used  on  average  (SD)  3.45  ( 1.28)  days/patient  in  Group  1  and 
2.1  (0.64)  days/patient  in  Group  2  (p  <  0.003).  Sixteen  Group-1  patients  con- 
tinued to  receive  O2  at  least  24  hours  after  achieving  a  room-air  Spo2  >  92%. 
Group  1  had  57  Spo2  measurements  and  Group  2  had  24  (p  <  0.003).  No  ad- 
verse clinical  events  ascribed  to  hypoxemia  were  noted  in  either  group.  CON- 
CLUSIONS: Our  experience  suggests  that  implementing  a  uniform,  clinically 
appropriate  'stop  criterion'  for  low-flow  O2  therapy  in  nonthoracic  postoperative 
patients  can  shorten  the  duration  of  O2  therapy  and  reduce  the  number  of 
Spo2  measurements  without  incurring  additional  complications.  [Respir  Care 
1995;40(11):  1125-1 129] 


Introduction 

As  part  of  a  more  general  problem  regarding  the  misallo- 
cation1'2  of  respiratory  care,  practices  of  ordering  and  imple- 
menting oxygen  (Oi)  therapy  are  frequently  flawed.  For  ex- 
ample. Small  et  al3  demonstrated  that  58%  of  orders  for  O2  were 
incorrect,  and  that  the  practice  of  prescribing  O:  therapy  was 
more  error-prone  than  the  practice  of  prescribing  antibiotics. 
Similarly,  Brougher  et  al4  showed  that  70%  of  orders  for  O2 
failed  to  meet  physiologic  criteria  and  that  38%  of  orders  failed 


Mr  Komara  is  Supervisor,  Section  of  Respiratory  Therapy,  and  Dr  Stoller 
is  Head,  Section  of  Respiratory  Therapy  and  Director,  IH  Page  Center  for 
Medical  Effectiveness  Research,  Department  of  Pulmonary  and  Critical 
Care  Medicine — Cleveland  Clinic  Foundation,  Cleveland.  Ohio. 

The  authors  have  no  financial  interest  in  any  of  the  products  mentioned  in 
this  paper. 

Reprints:  James  K  Stoller  MD,  Pulmonary  and  Critical  Care  Medicine, 
A-90,  Cleveland  Clinic  Foundation,  9500  Euclid  Avenue,  Cleveland 
OH  44195. 


to  satisfy  combined  physiologic  and  clinical  guidelines.  In  a 
third  example  of  suboptimal  management  of  Ot  therapy,  Albin 
et  al5  observed  that  61  %  of  physician  orders  for  supplemen- 
tal O2  therapy  were  deemed  unnecessary,  but  that  20%  of  or- 
ders for  patients  exhibiting  hypoxemia  specified  O2  flows  too 
low  to  assure  adequate  Ot  saturation. 

Pulse  oximetry  is  widely  used  in  current  practice.  Because 
pulse  oximetry  measurement  of  oxyhemoglobin  saturation 
(Spo2)  is  widespread  and  less  invasive  than  other  methods, 
its  use  may  permit  more  rigorous  management  of  oxygena- 
tion, but  may  also  invite  monitoring  activity  that  is  disasso- 
ciated from  management  decisions.6-7  For  example,  Bowton 
et  al6  showed  that  desaturation,  detected  by  continuous  pulse 
oximetry,  elicited  adjustment  of  O2  therapy  in  fewer  than  30% 
of  patients  in  an  academic  medical  center.  In  another  series,7 
introducing  pulse  oximetry  caused  only  a  small  reduction 
( 10.3%)  in  the  frequency  of  arterial  blood  gas  (ABG)  analy- 
ses performed  in  surgical  ICU  patients  and  no  reduction  in 
the  frequency  of  ABG  determinations  in  medical  ICU  patients. 

The  growing  breach  between  gathering  monitoring  data 
and  treating  detected  abnormalities  highlights  the  need  for 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1125 


Postoperative  O  Protocol 


changing  current  practice.8  Respiratory  therapist-directed  pro- 
tocols represent  one  strategy  for  changing  current  practice  be- 
cause managerial  decisions  regarding  these  modalities  are  al- 
located to  respiratory  care  practitioners,  based  on  algorithms 
to  help  direct  clinical  decisions.  A  growing  body  of  literature 
supports  the  efficacy  of  therapist-driven  protocols  (also  known 
as  patient-driven  protocols)  and  confirms  advantages  when 
respirator}'  care  practitioners  allocate  some  diagnostic  and  ther- 
apeutic respiratory  care  services.9'14 

In  this  context,  the  goal  of  the  current  cohort  study  is  to 
examine  postoperative  O:  management  practices  when  anes- 
thesiologists and  surgeons  prescribe  and  manage  Ot  thera- 
py versus  when  O2  is  managed  using  a  therapist-directed  pro- 
tocol with  a  room-air  Spo:  5  92%  as  a  criterion  for  stopping 
O:  therapy.  The  decision  to  implement  an  Spo?  value  of  > 
92%  as  the  'stop  criterion'  for  discontinuing  supplemental 
O;  therapy  was  based  on  medical  necessity  guidelines  es- 
tablished by  the  American  Association  for  Respiratory  Care, 
American  College  of  Chest  Physicians,  and  other  current  re- 
search findings.415  17 


Methods 

Practices  of  discontinuing  postoperative  Ot  were  exam- 
ined for  40  patients  admitted  to  the  postanesthesia  care  unit 
(PACU)  at  the  Cleveland  Clinic  Foundation  after  patients  un- 
derwent surgery  other  than  thoracic  or  cardiac  surgery.  Two 
patient  groups  were  considered.  In  the  standard-practice  group 
(Group  1.  n  =  20).  decisions  regarding  prescribing  and  dis- 
continuing Oi  were  made  by  the  anesthesiology  staff  in  the 
PACU  with  co-management  by  the  responsible  surgeons  once 
patients  returned  to  the  nursing  floor.  In  the  protocol  group 
(Group  2,  n  =  20),  initial  orders  for  Ot  were  normally  made 
by  the  PACU  Anesthesiology  staff,  but  subsequent  monitoring 
of  oxygenation  and  decisions  regarding  discontinuing  O2  ther- 
apy were  made  by  the  respiratory  care  practitioners  assigned 
to  the  nursing  floors  to  which  these  patients  returned  after 
PACU  discharge.  The  decision  to  stop  O2  therapy  was  made 
in  accordance  with  an  algorithm  (Fig.  1 )  using  a  stop  crite- 
rion of  Spo:  ^  92%  measured  on  room  air  and  stable  for  at  least 
20  minutes.  Three  exceptions  to  using  this  stop  criterion  were 


Preoperative  Assessment 


Postoperative  Assessment 


Yes  to  all  (Patient  is  eligible  tor  protocol) 


Use  92%  stop  criterion 


No  to  any  (Patient  is  ineligible  for  protocol) 


Management  of  postoperative 
02  via  ABG/Spo2  with 
appropriately  modified  target 
Spo2  value 


Increase  Foo2and 

notify  physicians 


Continue  current 
O2  therapy 


Low  flow  02  therapy 
at  prescribed  flowrate 


Discontinue  02  therapy 


Fig.  1 .  Algorithm  illustrating  the  use  of  a  protocol  for  managing  and  discontinuing  postoperative  oxygen  (02)  therapy.  Spo;  =  oxyhemoglobin 
saturation  as  measured  by  pulse  oximetry;  Sao..  =  oxyhemoglobin  saturation  in  arterial  blood;  ABG  =  arterial  blood  gas  (analysis);  Foo?  = 
fractional  concentration  of  02  delivered.  Based  on  AARC  Clinical  Practice  Guidelines  and  Reference  17. 


1 26 


Respiratory  Care:  •  November  '95  Vol  40  No 


Postoperative  Oi  Protocol 


recognized:  ( 1 )  the  patient  was  known  to  be  hypoxic  pre- 
operatively  (ie,  room-air  Spo2  <  90%  and  Pao:  ^  60  torr),  (2) 
the  patient  was  known  to  be  hypercapnic  preoperatively  (ie, 
resting  room-air  Paco:  ^  45  torr),  and  (3)  the  correlation  be- 
tween arterial  oxyhemoglobin  saturation  (Sao:)  and  Spo2  was 
known  to  be  poor  (ie,  values  differed  by  >  3%).  In  these  3  cir- 
cumstances, O:  was  continued  or  the  decision  to  discontin- 
ue O:  was  based  on  ABG  measurements,  which  were  obtained 
sparingly  and  at  the  respiratory  care  practitioners'  and/or  physi- 
cians' discretion. 

The  policy  by  which  respiratory  care  practitioners  could 
manage  monitoring  and  discontinuing  O2  was  implemented 
in  March  1 992.  This  study  compares  practices  for  the  protocol 
group  after  this  policy  was  begun  to  a  standard-practice  group 
enrolled  before  the  protocol  was  implemented.  Patients  in  the 
study  comprised  a  convenience  sample  selected  over  two  1- 
month  time  periods  from  approximately  1 ,250  eligible  patients 
admitted  to  the  PACU.  Patients  were  enrolled  on  days  when 
the  study  investigators  were  available.  By  assembling  a  con- 
venience sample  over  2  months  rather  than  a  consecutive  se- 
ries, a  larger  sample  of  managing  anesthesiologists  in  the  stan- 
dard-practice group  was  represented. 

Strategies  for  monitoring  oxygenation  differed  between 
Groups  1  and  2.  Specifically,  in  Group  1 ,  Spo:  measurements 
were  repeated  at  the  discretion  of  the  anesthesiology  and 
surgery  staff;  whereas,  in  Group  2,  Spo:  measurements  were 
performed  only  at  prescribed  intervals — on  the  second  post- 
operative day  following  the  patient's  discharge  from  PACU 
and  approximately  every  12  hours  thereafter  until  the  stop 
criterion  was  satisfied.  Measurements  of  Spo;  were  performed 
using  a  Criticare  503  pulse  oximeter  (Critical  Care  Systems 
Inc.  Milwaukee  WI)  and  a  nondisposable  digit  sensor. 

The  primary  outcome  measures  in  the  study  included  the 
duration  of  postoperative  O2  therapy  and  the  frequency  with 
which  O:  continued  to  be  prescribed  when  no  longer  indi- 
cated (ie.  after  room-air  Spo:  was  >  92%).  Secondary  outcome 
measures  included  reports  (by  physicians  and/or  nurses)  of 
hypoxemia  and  of  adverse  postoperative  events  attributed  to 
hypoxemia  as  ascertained  by  retrospective  chart  review.  Clin- 
ical data  for  respiratory  care  services  were  gathered  using  a 
respiratory  care  management  information  system  (CliniVision, 
Nellcor  Puritan-Bennett  Corp,  Carlsbad  CA).  Costs  of  pro- 


viding oximetry  and  Ch  administration  were  based  on  time- 
motion  analyses  performed  by  the  Cleveland  Clinic  Foun- 
dation Department  of  Management  Engineering  and  included 
a  detailed  analysis  of  both  fixed  and  variable  costs  (eg,  equip- 
ment, labor,  and  supplies). 

Statistical  comparison  of  differences  between  groups  was 
performed  using  Mann-Whitney  Rank  Sum  Tests.  Data  are 
presented  as  mean  (SD).  Comparisons  yielding  p  <  0.05  were 
considered  statistically  significant. 

Results 

The  demographic  characteristics  of  Groups  1  and  2  show 
no  significant  differences  in  age,  gender,  or  racial  distribu- 
tion (Table  1 ).  Recent  preoperative  pulmonary  function  tests 
were  available  for  3/20  (15%)  Group- 1  patients,  whose  mean 
(SD)  percent-predicted  FEV,  was  60.7  (8. 1 )%  and  FEV,/FVC 
was  76.0  (7.8),  indicating  mild  to  moderate  airflow  obstruction. 
Most  patients  in  both  groups  (Group  1 ,  60%  and  Group  2,  70%) 
underwent  abdominal  surgery,  with  the  remaining  patients 
undergoing  orthopedic  or  other  procedures. 

As  shown  in  Table  2,  the  mean  (SD)  Spo:  at  which  post- 
operative O2  therapy  was  discontinued  in  Group  1  was  95.2 
(1.1)%.  Twelve  of  20  (60%)  patients  in  this  group  had  writ- 
ten orders  specifying  that  O2  should  be  discontinued  only 
once  room-air  Spo:  exceeded  95%  (ie,  stop  criterion  was  Spo, 
>95%).  Also,  6  of  these  had  an  Spo,  stop  criterion  that  ex- 
ceeded the  patient's  own  preoperative  room-air  Spo2  (mean 
[SD]  92.8  [1.2]%). 

Of  the  57  room-air  Spo2  measurements  made  in  Group- 
1  patients,  31  (54%)  showed  saturation  values  >  93%.  Six- 
teen of  20  Group- 1  patients  (80%)  continued  to  receive  sup- 
plemental O2  for  at  least  24  hours  after  achieving  a  room- 
air  Spo2  of  92%,  the  stop  criterion  employed  in  Group  2. 
Furthermore,  3  of  20  (15%)  Group- 1  patients  were  dis- 
charged from  the  hospital  without  achieving  their  post- 
operative stop  criterion. 

Table  3  presents  the  frequency  of  pulse  oximetry  use  and 
the  costs  of  providing  pulse  oximetry.  As  shown,  the  mean 
number  of  Spo:  measurements/patient  after  PACU  discharge 
was  lower  among  Group-2  members,  as  were  direct  oxime- 
try costs  (p<  0.003). 


Table  1 .      Demographic  Characteristics  of  Patients  in  Group  I  and  Group  2* 


Group 


Mean  Age  (SD) 

Gender 

Race 

Types  of  Surgery  (n) 

60.5  (10.5)  years 

10  Male 

19  Caucasian 

Abdominal  (12) 

(Range,  40-78) 

10  Female 

1  Noncaucasian 

Orthopedic  (8) 

63.7  (14.1  (years 

1 1  Male 

18  Caucasian 

Abdominal  (14) 

(Range.  27-87) 

9  Female 

2  Noncaucasian 

Orthopedic  (5) 
Other ( 1 ) 

1 .  Standard  Practice 


:  No  significant  differences  between  Group  1  (Standard  Practice)  and  Group  2  (Protocol) 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1127 


Postoperative  O  Protocol 


Table  2-      Comparison  of  Criteria  for  Discontinuing  Oxygen  Therapy  in 
Group  I  vs  Group  2 


Group 


Method  To  Assess  Criterion  for  Stopping  O; 

Need  for  Oi  (O;  saturation ) 


I .  Standard  Practice       Decision  made  by 
physician 


Protocol  standard 


95.2  (1.1,  SD)% 

(Range  939r-96<7< ) 
I'M',  [2], 94%  [5], 
95%  [1],  9692  [12]) 

°2'<  (stable  on  room 
air  for  >  20  minutes) 


Table  3.      Frequency  of  Pulse  Oximetry  Use  and  Associated  Costs 
Mean(SD) 

Oximeter  Total  Direct 

Group  n     Measurements/      Oximeter  Oximetry 

Patient         Measurements    Cost/Patient 


1 .  Standard  Practice   20* 

2.  Protocol  20 


2.9(1.57) 

1.2(0.41) 


57'  $18.64(10.23) 

24  $7.84(2.68) 


*  3  of  Group- 1  patients  failed  to  achieve  oxygen  discontinuation  criteri- 
on during  hospital  stay. 
;  p  <  0.003.  Group  1  vs  Group  2 


1  and  7  from  Group  2).  no  preoperative  Spo:  or  ABG  anal- 
ysis was  recorded. 

Retrospective  review  of  patients'  medical  records  showed 
that  no  adverse  events  were  ascribed  to  hypoxemia  in  either 
study  group.  As  such,  the  accelerated  discontinuation  of  O: 
in  Group-2  patients  was  not  associated  with  complications, 
in  the  current  series. 


Pulse  Oximetry 


02  Administration 


Fig.  2.  Cost  comparison  data  for  standard  practice  (Group  1 
n  =  20)  vs  protocol  (Group  2  ■,  n  =  20)  patients. 
*  p  <  0.003. 


Discussion 


Table  4  presents  the  duration  of  postoperative  Ot  thera- 
py and  costs  associated  with  O2  administration.  As  with  the 
data  on  oximetry  described  in  Table  3,  Group-2  patients  re- 
quired shorter  courses  of  postoperative  O2  therapy  than  Group- 
1  patients,  and  the  costs  of  providing  O2  therapy  were  lower 
(p  <  0.003).  Total  costs  for  O2  administration  and  pulse  oxime- 
try use  are  depicted  in  Figure  2. 

Table  4.      Duration  of  Postoperative  Oxygen  Therapy  and  Costs  of 
Oxygen  Administration  in  Group  1  vs  Group  2  Mean  (SD) 


Group 


O:  Therapy  Total  Duration         Direct 

Duration/      O;  Therapy         0:Cost/ 

Patient  (Days)       (Days)  Patient 


1 ,  Standard  Practice  20  3.45(1.28)*         69*         $27.94(10.33)* 

2,  Protocol  20  2.10(0.64)  42  $17.01(4.47) 


p  <  0.003.  Group  I  vs  Group  2 


As  another  indicator  of  attention  to  Spo:  measurements 
in  clinical  management  of  these  patients,  the  frequency  of 
measuring  preoperative  saturation  values  was  also  exam- 
ined. Despite  regular,  mandatory  dependence  on  Sp(>  data 
in  the  operating  room  and  PACU.  a  review  of  the  medical 
records  of  all  40  patients  showed  thai  in  32.595  (6  from  Group 


This  study  extends  prior  research  that  examined  the  fre- 
quency of  misallocation  of  respiratory  care  services  in  gen- 
eral and  of  O2  administration  and  monitoring  in  particular. 
Specifically,  estimates  of  the  frequency  of  overordering  O2 
range  from  23%  to  61%  and  estimates  of  underordering  range 
from  1 1%  to  20%.2"5  Although  this  study  does  not  permit  a 
conclusion  about  whether  it  was  the  92%  Spo:  stop  criteri- 
on itself  or  the  respiratory  care  practitioners  as  implementors 
that  caused  the  observed  benefits,  our  findings  support  prior 
conclusions  that  respiratory  care  practitioners  are  more  like- 
ly to  successfully  implement  practice  guidelines  than  are  other 
health-care  providers.  For  example,  a  study  by  Browning  et 
al9  showed  that  the  frequency  of  inappropriately  ordered  ABG 
analyses  was  decreased  after  appropriateness  guidelines  were 
disseminated  to  practitioners  and  that  respiratory  care  prac- 
titioners were  less  likely  to  order  inappropriate  ABG  analy- 
ses than  were  other  health-care  providers.  Initial  experience 
in  our  institution  with  the  Respiratory  Therapy  Consult  Ser- 
vice also  suggests  that  respiratory  care  practitioners  are  more 
likely  to  employ  algorithms,  and  that  use  of  patient-driven  pro- 
tocols is  associated  with  fewer  inappropriate  orders  for  res- 
piratory care  services.1 ' 

Our  data  also  suggest  that  closer  attention  should  be  given 
lo  assessing  preoperative  oxygenation  in  order  to  better  es- 
tablish appropriate  postoperative  therapeutic  end  points.  F01 
example,  we  found  that  most  patients  in  the  standard-prac- 
tice group  continued  10  receive  supplemental  oxygenation 


1128 


RESPIRATORS  CARE  •  NOVEMBER  '95  VOL  40  No 


Postoperative  O  Protocol 


for  at  least  24  hours  after  achieving  a  room-air  Sp0:  >  92%. 
Also  in  this  group,  patients  for  whom  a  preoperative  mea- 
surement of  oxyhemoglobin  saturation  was  recorded  had 
an  Spo:  stop  criterion  that  often  exceeded  their  preopera- 
tive room-air  saturation  value.  Several  interpretations  may 
explain  this  phenomenon.  Managing  physicians  may  have 
desired  a  greater  margin  of  oxygenation  after  surgery,  though 
prior  research  suggests  that  in  Caucasians,  Spo;  ^  92%  as- 
sures adequate  arterial  oxygenation,  even  in  critically  ill  pa- 
tients being  weaned  from  mechanical  ventilation.17  Alter- 
nately, it  is  possible  that  O2  was  prescribed  with  relative  inat- 
tention to  physiologic  principles.18  Although  our  study  does 
not  assess  the  reason  for  differences  between  preoperative 
and  postoperative  saturation  targets,  prior  research  shows 
that  physicians  prescribe  O2  less  precisely  than  they  pre- 
scribe antibiotics,3  and  that  O2  is  frequently  both  overordered 
(ie,  prescribed  for  patients  with  adequate  saturation)  and  un- 
derordered  (not  prescribed  for  hypoxemic  patients  or  pre- 
scribed in  inadequate  concentrations).35 

Our  findings  must  be  interpreted  cautiously  in  view  of  sev- 
eral potential  shortcomings  of  this  study.  First,  because  we 
studied  a  convenience  sample  with  a  small  number  of  patients 
in  a  specific  hospital  setting  (ie,  PACU  and  medical/surgi- 
cal nursing  floors),  our  findings  may  not  be  widely  gener- 
alizable.  On  the  other  hand,  previous  studies  do  suggest  that 
Oi  therapy  is  frequently  misallocated  in  many  clinical  set- 
tings, suggesting  a  widespread  need  for  implementing  bet- 
ter management  strategies.  Our  findings  are  consistent  with 
previous  observations  that  physicians  often  employ  a  wide 
range  of  Spo;  criteria  when  assessing  oxygenation.17  A  sec- 
ond shortcoming  is  that  the  use  of  noncontemporaneous  con- 
trols could  introduce  performance  bias,14  if  the  care  provid- 
ed to  Group- 1  patients  had  changed  from  that  provided  to 
Group-2  patients  due  to  the  passing  of  time. 

Finally,  the  comparison  between  physician-directed  care 
and  therapist-directed  care  using  a  specific  stop  criterion 
does  not  permit  a  conclusion  about  whether  the  therapist  or 
the  stop  criterion  is  responsible  for  the  observed  im- 
provements in  Oi-therapy  management.  We  believe  that  both 
elements  are  required  for  maximal  effect.  Certainly,  ther- 
apists' proficiency  with  monitoring  techniques  and  success 
using  guidelines  recommend  them  as  important  participants 
in  02-therapy  management. 

ACKNOWLEDGMENTS 

The  authors  thank  Beth  Dobish  for  her  expert  assistance  in  preparing 
the  manuscript. 


REFERENCES 

Stoller  JK.  Misallocation  of  respiratory  care  services:  time  for  a  change 
(editorial).  RespirCare  1993;38(3):263-266. 
Kester  L.  Stoller  JK.  Ordering  respiratory  care  services  for  hospi- 
talized patients:  Practices  of  overuse  and  underuse.  Cleve  Clin  J  Med 
1992:59(61:581-585. 

Small  D,  Duha  A.  Wieskopf  B.  Dajezman  E.  Laporta  D.  Kreisman  H. 
et  al.  Uses  and  misuses  of  oxygen  in  hospitalized  patients.  Am  J  Med 
l992;92(6):591-595. 

Brougher  LI.  Blackwelder  AK.  Grossman  GD,  Straton  GW.  Ef- 
fectiveness of  medical  necessity  guidelines  in  reducing  cost  of  oxy- 
gen therapy.  Chest  1986;90(5):646-648. 

Albin  RJ,  Criner  GJ.  Thomas  S,  Abou-Jaoude  S.  Pattern  of  non-ICU 
inpatient  supplemental  oxygen  utilization  in  a  university  hospital. 
Chest  1992;102(6):1672-1675. 

Bowton  DL.  Scuderi  PE,  Harris  L.  Hoponik  EF.  Pulse  oximetry  mon- 
itoring outside  the  intensive  care  unit:  progress  or  problem?  Ann  In- 
tern Med  1991:115(61:450-454. 

Inman  KJ,  Sibbald  WJ,  Rutledge  FS.  Speechley  M,  Martin  CM. 
Clark  BJ.  Does  implementing  pulse  oximetry  in  a  critical  care  unit 
result  in  substantial  arterial  blood  gas  savings?  Chest  1993:104(2): 
542-546. 

Kacmarek  RM,  Hess  D.  Stoller  JK.  Perspectives  on  monitoring  in 
respiratory  care.  In:  Monitoring  in  respiratory  care.  Kacmarek  RM, 
HessD.  Stoller  JK  (editors)  St  Louis:  Mosby- Yearbook.  1993. 
Browning  JA.  Kaiser  DK.  Durbin  CG  Jr.  The  effect  of  guidelines 
of  the  appropriate  use  of  arterial  blood  gas  analysis  in  the  intensive 
care  unit.  RespirCare  1989;34(4):269-276. 
Stoller  JK,  Haney  D,  Burkhart  J,  Fergus  L,  Giles  D,  Hoisington  E. 
et  al.  Physician-ordered  respiratory  care  vs  physician-ordered  use  of 
respiratory  care  consult  service:  early  experience  at  the  Cleveland 
clinic  foundation.  RespirCare  1993;38(11):1 143-1 154. 
Smoker  JM,  Tangen  MI.  Stephen  MF,  Hess  D,  Rexrode  WO.  A  pro- 
tocol to  assess  and  administer  aerosolized  bronchodilator  therapy. 
RespirCare  1986;3 1(91:780-785. 

Hart  SK,  Dubbs  W.  Gil  A,  Myers-Judy  M.  The  effects  of  therapist 
evaluation  of  orders  and  interaction  with  physicians  on  the  appro- 
priateness of  respiratory  care.  RespirCare  1989;34:(3)185-190. 
Haney  D.  Orens  D.  Kester  L.  Stoller  JK.  Impact  of  a  respiratory  ther- 
apy consult  service  on  inappropriateness  of  orders  for  respiratory  care 
(abstract).  Respir  Care  1993i38(  1 1 1: 1305. 

Weber  K,  Milligan  S.  Therapist-driven  protocols:  the  state-of-the- 
art  (Conference  Summary).  RespirCare  1994;39(7):746-756. 
American  Association  for  Respiratory  Care.  AARC  clinical  practice 
guidelines:  incentive  spirometry.  RespirCare  199 1:36(1 2 ):  1402-1405. 
American  College  of  Chest  Physicians,  National  Heart,  Lung  and 
Blood  Institute.  The  national  conference  on  oxygen  therapy.  Chest 
1984:86(2):234-247. 

Jubran  A,  Tobin  MJ.  Reliability  of  pulse  oximetry  in  titrating  sup- 
plemental oxygen  therapy  in  ventilator  dependent  patients.  Chest 
1990:97(6):1420-I425. 

Zibrak  JD.  Monitoring  oxygen  therapy — is  it  worth  the  cost?  (edi- 
torial). Chest  1986:90(51:629. 

Feinstein.  AR.  An  outline  of  cause-effect  evaluations.  In:  Clinical 
epidemiology:  the  architecture  of  clinical  research.  Philadelphia:  WB 
Saunders.  1985:45-46. 


Respiratory  Care  •  November  '95  vol  40  No  1 


1129 


Reviews,  Overviews,  &  Updates 


Ventilator-Associated  Pneumonia:  An  Update  for  Clinicians 

Marin  H  Kollef  MD  and  Patricia  Silver  ME  RRT 


I.      Introduction 
II.      Aspects  To  Be  Considered 

A.  Epidemiology 

B.  Mortality 

C.  Pathogenesis 

D.  Clinical  Diagnosis 

E.  Diagnostic  Techniques 

F.  Prevention  &  Treatment 
III.      In  Summary 


Introduction 


Aspects  To  Be  Considered 


The  leading  cause  of  death  from  hospital-acquired  infections 
is  pneumonia.1  The  estimated  prevalence  of  nosocomial  pneu- 
monia in  intensive  care  units  (ICUs)  ranges  from  10  to  65% 
with  case  fatality  rates  of  13  to  55%. 2'7  Ventilator-associat- 
ed pneumonia  (VAP)  specifically  refers  to  pneumonia  de- 
veloping in  a  mechanically  ventilated  patient  later  than  48  hours 
after  intubation  (ie.  no  evidence  suggested  the  presence  or  like- 
ly development  of  pneumonia  at  the  time  of  untubation).8  The 
clinical  importance  of  VAP  is  demonstrated  by  several  recent 
investigations  suggesting  that  its  occurrence  is  an  indepen- 
dent determinant  of  mortality  for  critically  ill  patients  requiring 
mechanical  ventilation.''1"  More  importantly,  emerging  clin- 
ical data  now  suggest  that  the  application  of  new  management 
strategies  for  the  prevention  of  VAP.  including  more  specific 
indications  for  antimicrobial  use.  could  result  in  improved  pa- 
tient outcome.-1  '"•"  The  article  that  follows  is  not  a  compre- 
hensive review  but  addresses  many  of  the  developing  and  con- 
troversial issues  that  we  believe  will  guide  the  future  course 
of  medical  care  and  investigation  of  VAP. 


t)r  Kollef  i>-  the  director  of  both  Respiratory  Therapy  and  the  Medical 
Intensive  Care  Unit,  and  Ms  Silver  is  clinical  specialist — Department  of 
Internal  Medicine.  Pulmonary  and  Critical  Care  Division.  Washington 
University  School  of  Medicine  and  Department  of  Respiratory  Therapy, 
Barnes  Hospital,  St  Louis,  Missouri. 

Reprints:  Mann  II  Kollcl  Ml).  Director.  Respiratory  Therapy  &  Medical 
Intensive  Care  Unit,  Pulmonarj  and  Critical  (arc  Division,  Washington 
I  Iniversity  School  of  Medicine,  Box  8052, 660  S  Euclid  Avenue,  St  Louis 
MO  631  10. 


Epidemiology 

Using  multivariate  methods,  a  number  of  investigators  have 
identified  various  risk  factors  associated  with  the  develop- 
ment of  VAP:  4A1I|:  (Table  1 ).  These  risk  factors  appear  to 
increase  the  likelihood  that  VAP  will  develop,  by  increasing 
the  bacterial  burden  of  colonization  in  the  oropharynx  and  stom- 
ach (eg,  antacids,  histamine  type-2-receptor  antagonists,  prior 
use  of  antibiotics)  or  by  increasing  the  risk  of  aspiration  (eg. 


Table  1 .      Risk  Factors  for  Ventilator-Associated  Pneumonia 


Risk  Factor 

Reference 

Duration  of  mechanical  ventilation 

2.3 

Aspiration  of  gastric  contents 

3.6 

Chronic  obstructive  pulmonary  disease 

3,6,12 

Histamine  type-2-receptor  antagonist 

4 

Nasal  intubation/sinusitis 

39 

Use  of  PEEP 

3 

Reintubation 

3 

ICP  monitoring/depressed  consciousness 

4.b 

Fall-Winter  season 

4 

24-h  mechanical -ventilatoi  -circuit  changes 

4 

Thoracic/upper  abdominal  surgery 

6 

Age 

6.11 

Multiple  acquired  organ-system  derangements 

II 

Prior  antibiotic  administration 

II 

Supine  head  positioning 

11 

Duration  of  hospitalization  prior  to  nicchamc.il 

ventilation 
.iin.il  pressui 

12 

PPEP  =  positive  end-expirator)  pressure;  ICP  =  intrac 

130 


Inspiratory  Carp:  •  Novfmbfr  '95  Vol  40  No  1 1 


Ventilator-Associated  Pneumonia 


supine  positioning,  endotracheal  tube  or  ventilator-circuit  ma- 
nipulation, depressed  consciousness)  (Fig.  1 ).  Accordingly, 
clinical  trials  have  been  performed  with  the  main  goals  of  mod- 
ifying these  risk  factors  in  order  to  improve  patient  outcomes 
(eg.  reduce  bacterial  colonization  of  the  upper  airway  and  stom- 
ach, aspiration,  and  the  occurrence  of  V  AP).  Such  trials  have 
incorporated  measures  aimed  at  modifying  previously  identi- 
fied patient  risk  factors  for  VAP  including  the  avoidance  of 
gastric  alkalinization,1314  the  maintenance  of  a  semi-erect  posi- 
tioning of  the  head,15  administration  of  enteral  feeding  solutions 
directly  into  the  jejunum16  or  close  monitoring  of  residual  vol- 
umes for  intragastric  feedings,17  and  changing  ventilator  cir- 
cuits every  48  hours  instead  of  daily.418 


Transthoracic  Infection 

Contaminated  Aerosol 

Bacteremia 

(?  translocation) 


PATHOGENESIS 

RISK  FACTORS 

1)  Gastric  alkalinization 
2}  Prior  antimicrobials 

3)  Nasal  intubation 

4)  Malnutrition 

Gastric/Oropharyngeal/ 

Sinus/Subglottic 
Bacterial  Colonization 

«- 

i 

1)  Supine  positioning 

2)  Circuit/Airway 
manipulation 

Aspiration 

[LRT  detense 
mechanisms] 

1 

J 

1}  Immunosuppression 
2)  Radiation/Scarring 
3}  Malnutrition 
4}  Malignancy 

Bronchiolitis 

I 

Bronchopneumonia 

; 

Lung  Abscess 

Fig.  1 .  Flow  chart  showing  pathophysiologic  mechanisms  for  infec- 
tion of  lower  respiratory  tract  (LRT). 


Recently,  several  groups  of  investigators  have  identified 
the  prior  administration  of  broad-spectrum  antibiotics  as  an 
important  risk  factor  for  the  emergence  of  nosocomial  in- 
fections due  to  highly  virulent,  antibiotic-resistant  micro- 
organisms. |l)  -  Our  group  has  previously  shown  that  the  prior 
administration  of  antibiotics  is  an  independent  risk  factor  for 
the  development  of  VAP. ' '  The  predominant  organisms  re- 
covered from  the  respiratory  tract  secretions  of  these  patients 
included  antibiotic-resistant  Gram-negative  bacilli  and  Staphy- 
lococcus aureus.11-23  Similarly,  Rello  and  co-workers  found 
that  the  prior  administration  of  antibiotics,  particularly  third- 
generation  cephalosporins,  predicted  the  development  of  VAP 
due  to  methicillin-resistant  Staphylococcus  aureus  (MRSA):4 
and  antibiotic-resistant  Gram-negative  bacilli  that  they  termed 
high-risk  organisms  due  to  their  associated  increased  mor- 


tality.10 These  same  investigators  demonstrated  that  patients 
without  prior  antimicrobial  treatment  were  significantly  more 
likely  to  develop  VAP  due  to  Hemophilus  influenzae,  which 
was  associated  with  good  clinical  outcomes.1025 

The  studies  linking  previous  antimicrobial  exposure  to  the 
development  of  antibiotic-resistant  infections  support  the  con- 
cept that  there  is  a  clinical  'price'  to  be  paid  for  the  routine 
use  of  broad-spectrum  antibiotics  in  hospitalized  patients.  Pro- 
phylactic administration  of  aerosolized  antibiotics26  and  the 
topical  administration  of  oropharyngeal  and  intragastric  an- 
tibiotics (ie,  selective  digestive  decontamination  [SDD])27"30 
have  also  been  shown  to  predispose  to  the  development  of 
antibiotic-resistant  infections.  These  investigations  highlight 
the  importance  of  previous  antimicrobial  administration  as 
a  predisposition  to  the  subsequent  development  of  high-risk 
nosocomial  infections,  and  the  findings  suggest  that  the  in- 
discriminate use  of  these  agents  should  be  avoided.  Their  use 
is  indicated  by  the  presence  or  strong  clinical  suspicion  of  un- 
derlying infection. 

Mortality 

The  development  of  VAP  is  associated  with  increased  mor- 
tality in  patients  with  acute  respiratory  failure.511-23  However, 
it  remains  uncertain  whether  patients  die  due  to  the  development 
of  VAP  or  whether  VAP  is  merely  a  marker  or  epiphenomenon 
of  the  patient's  underlying  burden  of  illness,  resulting  in  death. 
In  a  case-control  study  aimed  at  addressing  this  issue,  Fagon 
and  colleagues4  found  the  mortality  rate  of  patients  with  VAP 
to  be  54.2%  compared  with  a  mortality  rate  for  control  pa- 
tients of  27.1%,  yielding  an  attributable  mortality  due  to  VAP 
of  27.1%  (risk  ratio  for  death,  2.0).  For  patients  with  VAP  due 
to  high-risk  antibiotic-resistant  bacteria  (ie,  Pseudomonas 
aeruginosa  and  Acinetobacter  sp),  the  mortality  rate  was  7 1 .4%, 
yielding  an  attributable  mortality  due  to  antibiotic-resistant 
VAP  of  42.8%  (risk  ratio  for  death,  2.5). 

Our  own  data  have  shown  that  the  development  of  VAP 
due  to  similar  high-risk  pathogens  is  an  independent  predictor 
of  hospital  mortality  even  after  patient  demographic  factors 
and  underlying  severity  of  illness  are  controlled  for.31  We 
demonstrated  that  patients  with  VAP  due  to  a  high-risk 
pathogen  (ie,  Pseudomonas  aeruginosa,  Acinetobacter  sp,  and 
Xanthomonas  maltophilia)  had  a  significantly  higher  mor- 
tality rate  (65%)  compared  to  patients  with  late-onset  VAP 
due  to  other  pathogens  (31.3%;  relative  risk.  2.07;  95%  CI, 
1.29  to  3.35)  or  compared  to  patients  without  late-onset  VAP 
(37.4%;  relative  risk,  1.74;  95%  CI.  1.21  to  2.50;  p<  0.05). 
Therefore,  it  appears  that  important  subgroups  of  VAP  (eg, 
VAP  due  to  high-risk  antibiotic-resistant  pathogens)  may  be 
responsible  for  patient  mortality  in  excess  of  that  attributable 
to  patients'  underlying  severity  of  illness. g-31 

In  addition  to  its  impact  on  patient  outcome,  the  develop- 
ment of  VAP  also  adversely  affects  the  hospitals  caring  for 
these  critically  ill  patients  because  the  hospitals  are  rarely  fully 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1131 


Ventilator- Associated  Pneumonia 


reimbursed  for  their  care.  In  one  study  from  Rhode  Island.32 
the  occurrence  of  nosocomial  pneumonia,  including  VAP,  re- 
sulted in  a  net  loss  of  $5,800  per  hospital  case.  Thus,  efforts 
have  been  increased  to  identify  patients  at  risk  for  VAP  early. 
in  order  to  eliminate  risk  factors  when  possible. '  Kelleghan 
and  colleagues"  have  demonstrated  that  the  rigorous  im- 
plementation of  simple  infection-control  and  quality-im- 
provement policies  (eg.  handwashing,  ventilator  maintenance, 
elevation  of  the  head  of  bed)  significantly  reduced  by  519c 
the  incidence  of  VAP  at  their  institution  resulting  in  substantial 
cost  savings  ($105,000  from  the  costs  associated  with  the  15 
cases  of  VAP  that  were  prevented  during  the  study  year). 

Pathogenesis 

Aerobic  Gram-negative  bacilli  and  Staphylococcus  au- 
reus are  the  major  pathogens  responsible  for  VAP,  ac- 
counting for  50-70%  of  all  cases.''210  VAP  can  develop  by 
a  number  of  different  mechanisms  (Fig.  1 ).  including  as- 
piration of  colonized  secretions  from  the  upper  airway  or 
stomach,  bacteremia  from  another  established  focus  of  in- 
fection with  secondary  infection  of  the  lung,  inhalation  of 
a  contaminated  aerosol  solution,  direct  transthoracic  inocu- 
lation, and.  possibly,  by  bacterial  translocation  through  the 
gastrointestinal  tract.1 34  Direct  aspiration  is  the  most  com- 
mon mechanism  responsible  for  the  development  of  VAP.1  •" 
Aspiration  of  small  volumes  of  secretions,  often  contain- 
ing large  concentrations  of  bacteria,  is  a  common  event  in 
hospitalized  patients,  especially  in  the  presence  of  impaired 
level  of  consciousness.35 

Animal  models  have  clearly  shown  that  aspirated  liq- 
uid boluses  contaminated  with  bacteria  cause  pneumonia.36 
Usually,  significantly  smaller  quantities  of  bacteria  are  re- 
quired to  cause  pneumonia  if  aspirated,  instead  of  being  in- 
troduced into  the  lung  by  the  aerosol  route.37  Endotracheal 
tubes  in  mechanically  ventilated  patients  probably  play  a 
major  role  in  predisposing  such  patients  to  aspiration  by  by- 
passing normal  protective  mechanisms  in  the  upper  airway 
and  by  allowing  secretions  to  pool  in  the  upper  part  of  the 
trachea.3*  Additionally,  when  endotracheal  tubes  are  placed 
nasally,  instead  of  through  the  mouth,  sinusitis  is  signifi- 
cantly more  likely  to  occur  due  to  blockage  of  the  ostia  of 
the  sinuses.3"'4"  The  occurrence  of  nosocomial  sinusitis  has 
been  associated  with  the  development  of  VAP.39  Culture 
results  from  the  maxillary  sinuses  in  patients  with  nosocomial 
sinusitis  often  yield  antibiotic-resistant  Gram-negative  bacil- 
li due,  in  large  part,  to  prior  antimicrobial  exposure.3'1 4"  How- 
ever, sinusitis  and  VAP  are  common  infections  occurring 
in  patients  with  respiratory  failure,  and,  to  date,  a  defini- 
tive causal  relationship  between  these  two  infections  has 
not  been  demonstrated.4"  Dental  plaque  has  also  been  shown 
to  be  colonized  with  potential  respiratory  pathogens  and  has 
also  been  implicated  as  a  source  of  infectious  aspirate  com- 
ing from  the  oropharynx  to  cause  VAP.41 


During  the  past  decade,  the  role  of  the  gastrointestinal  tract 
in  the  pathogenesis  of  VAP  has  been  of  great  interest.42  Gas- 
tric contents  are  normally  sterile  due  to  the  bactericidal  ac- 
tivity of  hydrochloric  acid.43  Bacterial  colonization  of  the  stom- 
ach has  been  associated  with  a  number  of  factors  frequent- 
ly present  in  hospitalized  patients,  including  advanced  age, 
underlying  gastrointestinal  disorders,  achlorhydria.  malnutrition, 
antacid  administration,  and  the  use  of  histamine  type-2-receptor 
antagonists.44-45  Recumbent  supine  positioning  of  the  head  and 
the  presence  of  various  medical  devices  (eg.  nasogastric  tubes, 
feeding  tubes)  appear  to  facilitate  both  retrograde  coloniza- 
tion of  the  oropharynx  from  the  stomach  and  direct  aspiration 
of  gastric  contents  into  the  lower  airways.  '■46-47  One  study,  using 
radiolabeled  gastric  contents,  demonstrated  that  supine  posi- 
tioning of  the  head  increased  the  prevalence  of  aspiration  and 
bacterial  colonization  of  the  lower  airways  in  mechanically 
ventilated  patients;  whereas,  semirecumbent  and  supine  posi- 
tioning prevented  these  complications.15  Another  investiga- 
tion found  supine  positioning  of  the  head  to  be  an  indepen- 
dent risk  factor  for  the  development  of  VAP,  probably  by  al- 
lowing greater  aspiration  of  gastric  contents." 

Concerns  about  the  role  of  gastric  colonization  in  the  patho- 
genesis of  nosocomial  pneumonia  have  led  a  number  of  in- 
vestigators to  examine  the  impact  of  gastric  alkalization  on 
the  development  of  VAP.1314-4445  Gastric  alkalinization  (ie, 
administration  of  antacids  or  histamine  type-2-receptor  an- 
tagonists) is  frequently  used  in  the  ICU  in  an  effort  to  reduce 
the  frequency  of  upper  gastrointestinal  bleeding  related  to  stress 
ulcers.  Although  these  studies  generally  support  a  role  for  gas- 
tric alkalinization  in  the  pathogenesis  of  VAP,  methodologic 
problems  in  their  study  design  limit  the  strength  of  their  con- 
clusions and  probably  account  for  the  discrepant  results  found 
between  more  recent  studies.48"52  Although  debate  continues 
over  the  importance  of  gastric  colonization  as  a  risk  factor 
for  VAP,  most  investigators  agree  that  significant  aspiration 
of  contaminated  gastric  contents  into  the  lower  airway  can 
lead  to  the  development  of  VAP  and  to  direct  lung  injury.'-48 
Additionally,  it  appears  that  few  critically  ill  patients  have  clin- 
ically important  gastrointestinal  bleeding,  and  therefore  pro- 
phylaxis against  stress  ulcers  can  be  safely  withheld  from  most 
patients  unless  they  have  additional  risk  factors  for  gas- 
trointestinal bleeding  (eg,  coagulopathy). 52'n 

Clinical  Diagnosis 

VAP  is  usually  suspected  when  a  patient  who  requires  me- 
chanical ventilation  develops  a  new  or  progressive  pulmonary 
infiltrate,  with  fever,  leukocytosis,  and  purulent  tracheobronchial 
secretions.54  Many  noninfectious  causes  of  fever  and  pulmonary 
infiltrates  can  occur  in  mechanically  ventilated  patients  mak- 
ing the  described  clinical  criteria  nonspecific  for  the  diagnosis 
of  VAP.55  These  noninfectious  causes  of  fever  and  pulmonary 
infiltrates  include  chemical  aspiration  without  infection,  at- 
electasis, pulmonary  embolism,  ARDS,  pulmonary  hemor- 


I  132 


Respiratory  Cari  •  November  '95  Voi  40  No  I 


Ventilator-Associated  Pneumonia 


rhage,  lung  contusion,  infiltrative  tumor,  radiation  pneumonitis, 
and  drug  reaction. 

One  study56  of  patients  with  acute  lung  injury  used  autopsy 
results  to  show  that  clinical  criteria  alone  led  to  an  incorrect 
diagnosis  of  V  AP  in  29%  of  clinically  suspected  cases.  Sim- 
ilarly, a  study  of  147  mechanically  ventilated  patients  that 
used  quantitative  lower  airway  cultures  to  establish  the  di- 
agnosis of  VAP  found  that  clinical  variables  could  not  be  used 
to  accurately  distinguish  between  patients  with  and  without 
VAP.57  This  same  group  of  investigators  in  another  study58 
evaluated  the  accuracy  of  clinical  judgment  in  formulating 
treatment  plans  for  patients  with  suspected  VAP  compared 
with  quantitative  lower  airway  cultures  obtained  by  bron- 
choscopy. Compared  with  treatment  decisions  based  on  cul- 
ture specimens,  clinical  judgments  about  the  presence  of  VAP 
were  correct  only  62%  of  the  time.  More  startling  was  the  ob- 
servation that  only  33%  of  the  treatment  plans  were  deemed 
effective  on  the  basis  of  clinical  judgment  alone.  Most  clin- 
ical errors  resulted  in  the  unnecessary  prescription  of  antibiotics, 
failure  to  diagnose  VAP  accurately,  failure  to  treat  all  or- 
ganisms causing  polymicrobial  VAP.  and  failure  to  treat  VAP 
due  to  antibiotic-resistant  organisms.58  These  studies56-58  em- 
phasize the  important  limitations  of  bedside  clinical  parameters 
routinely  used  for  the  diagnosis  and  management  of  VAP. 

Similar  to  clinical  criteria,  radiographic  criteria  have  been 
shown  to  be  nonspecific  for  the  diagnosis  of  VAP.56-5y  One 
group  of  investigators  examined  the  chest  radiographs  of  69 
patients  who  had  died  in  respiratory  failure  and  upon  whom 
autopsies  had  been  performed.60  Of  the  30  patients  fulfilling 
radiographic  and  clinical  criteria  for  VAP.  only  1 3  were  found 
to  have  VAP  at  autopsy  (57%  false-positive  rate).  Stepwise 
logistic  regression  analysis  suggested  that  air  bronchograms 
were  the  only  radiographic  sign  that  might  predict  the  pres- 
ence of  VAP. 

Diagnostic  Techniques 

The  noted  limitations  and  inaccuracies  in  clinical  decision 
making  have  been  the  motivation  for  developing  new  tech- 
niques to  diagnose  VAP.  Examination  and  culture  of  tracheal 
aspirates  have  traditionally  been  used  to  aid  diagnosis  but  are 
clearly  nonspecific  for  establishing  the  diagnosis  of  VAP  be- 
cause tracheobronchial  bacterial  colonization  in  critically  ill 
patients  is  common.61-62  Three  methods  have  recently  been 
applied  to  tracheal  aspirates  in  an  attempt  to  improve  their 
diagnostic  specificity:  potassium  hydroxide  staining  for  the 
presence  of  elastin  fibers  (ie.  an  indication  of  parenchymal 
necrosis  due  to  VAP).63-64  quantitative  bacterial  cultures,6567 
and  testing  of  the  antibody  coating  of  bacteria.68  Each  of  these 
techniques  apparently  improve  the  overall  specificity  of  using 
tracheal  aspirates  to  diagnose  VAP;  however,  their  sensitivity 
varies  from  65  to  75%  limiting  their  routine  clinical  use. 

At  the  present  time  (1995),  bronchoscopic  sampling  of  the 
lower  airways,  using  either  a  protected  specimen  brush  (ie, 


double-sheathed  catheter  to  minimize  bacterial  contamina- 
tion) or  bronchoalveolar  lavage  (BAL)  appears  to  be  accepted 
as  the  most  accurate  method  of  diagnosing  VAP,  short  of  di- 
rect tissue  examination.54 -w  These  techniques  have  been  val- 
idated in  both  animal  models  and  clinical  trials.7" 7:  The  pro- 
tected-specimen-brush  procedure  involves  placing  the  tip  of 
the  bronchoscope  next  to  an  involved  bronchial  segmental  ori- 
fice and  then  advancing  the  protected  specimen  brush  through 
its  sheath  into  the  airway  for  sampling  of  uncontaminated  se- 
cretions.7:-71  BAL  involves  the  infusion  and  aspiration  of  ster- 
ile saline  through  a  flexible  fiberoptic  bronchoscope  wedged 
into  a  bronchial  segmental  orifice.  For  both  of  these  meth- 
ods, rigid  procedural  guidelines  are  available  to  minimize  con- 
tamination of  the  specimens  and  to  optimize  their  accuracy.55-72 

Quantitative  or  semiquantitative  cultures  are  usually  per- 
formed on  the  bronchoscopic  specimens,  and  the  diagnosis 
of  VAP  then  depends  on  exceeding  some  appropriate  thresh- 
old.73 Many  clinical  studies  have  shown  that  thresholds  of  103 
colony  forming  units  (cfu)/mL  for  protected-specimen-brush 
samples  and  104  cfu/mL  for  BAL  specimens  yield  the  best 
operating  characteristics  for  these  two  methods.73  The  diagnostic 
accuracy  of  these  threshold  values  has  recently  ( 1995)  been 
validated  in  a  study  of  patients  with  VAP  that  employed  im- 
mediate postmortem  lung  examination  as  the  diagnostic  gold 
standard.74  The  application  of  quantitative  thresholds  to  cul- 
tures obtained  from  airway  secretions  is  necessary  to  improve 
their  overall  diagnostic  specificity  due  to  the  presence  of  tra- 
cheobronchial bacterial  colonization.  However,  an  analyti- 
cal approach  to  clinical  decision  making  in  patients  with  VAP 
has  recently  suggested  that  threshold  values  lower  than  those 
currently  recommended  may  be  more  appropriate  in  patients 
suspected  of  having  VAP.  unless  the  risks  of  antibiotic  ther- 
apy are  judged  to  be  extreme.75 

The  derivation  of  quantitative  threshold  values  for  res- 
piratory specimens  in  patients  with  suspected  VAP  comes  from 
the  findings  of  quantitative  cultures  obtained  from  infected 
lung  tissue.72  Clinically  important  lung  infections  usually  con- 
tain bacteria  numbering  at  least  104  cfu/g  of  tissue  and  >  105 
bacteria/mL  of  exudate.72  The  volume  of  respiratory  secre- 
tions retrieved  by  a  protected  specimen  brush  is  approximately 
0.001  mL.  The  brush  sample  is  usually  diluted  in  1  mL  of  hold- 
ing medium,  resulting  in  a  100-  to  1,000-fold  dilution  of  the 
bacteria.  Therefore,  a  growth  of  >  103  cfu/mL  in  the  culture 
plate  indicates  an  initial  concentration  of  10s  to  106  bacteria 
in  the  pulmonary  secretions.72  Similarly,  BAL  fluid  is  esti- 
mated to  recover  at  least  5  to  10  times  the  number  of  organisms 
retrieved  by  the  protected  specimen  brush.72  A  colony  count 
of  104  cfu/mL,  therefore,  represents  105to  106  bacteria/mL 
of  infected  pulmonary  secretions. 

Although  bronchoscopic  methods  for  obtaining  lower  air- 
way specimens  are  generally  safe,  their  expense  plus  the  need 
for  a  trained  bronchoscopist  has  limited  their  general  appli- 
cation. Additionally,  it  has  yet  to  be  shown  that  the  ability  to 
obtain  specimens  from  the  lower  airway  with  these  invasive 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1133 


Ventilator- Associated  Pneumonia 


diagnostic  tools  has  influenced  patient  outcome  in  any  mean- 
ingful manner/''  These  limitations  to  the  bronchoscope  ap- 
proach and  the  studies" 7S  showing  the  limited  diagnostic  value 
of  these  methods  in  the  presence  of  antibiotic  therapy  have 
resulted  in  increased  enthusiasm  for  nonbronchoscopic  tech- 
niques that  can  obtain  specimens  more  readily  prior  to  admin- 
istering antibiotics.  Like  the  bronchoscopic  techniques,  the 
nonbronchoscopic  methods  use  quantitative  culture  thresh- 
olds to  improve  overall  diagnostic  accuracy. 

Blind,  nonbronchoscopic  sampling  of  lower  respiratory 
tract  secretions,  using  various  catheter  or  brush  devices  to 
obtain  specimens  for  quantitative  cultures,  has  been  exten- 
sively examined  as  an  alternative  diagnostic  method  in  cases 
of  suspected  VAP.7Q"82  Pham  and  co-workers74  found  that  the 
sensitivity  (100%)  and  specificity  (82.2%)  of  quantitative  bac- 
terial samples  obtained  with  one  of  these  devices  to  be  com- 
parable to  (if  not  better  than)  those  of  bronchoscopically  guid- 
ed protected-specimen-brush  cultures  (sensitivity  64.7%  and 
specificity  93.5%).  In  another  investigation,  blind  catheter 
lavage  of  the  lower  airway  was  demonstrated  to  have  a  sen- 
sitivity of  70%  and  a  specificity  of  69%  compared  to  post- 
mortem histologic  and  bacteriologic  analysis  of  lung  tissue.82 
These  results  compare  favorably  with  the  findings  of  an  ear- 
lier investigation  comparing  postmortem  tissue  examination 
with  culture  results  obtained  using  a  bronchoscopically  di- 
rected protected  specimen  brush.70 

We  recently  demonstrated  that  the  technique  of  catheter 
mini-BAL.  as  performed  by  respiratory  therapists,  is  a  safe 
and  technically  simple  procedure  for  obtaining  quantitative 
lower  airway  cultures  in  patients  requiring  mechanical  ven- 
tilation.83 More  importantly,  the  quantitative  culture  results 
obtained  by  mini-BAL  were  comparable  to  those  obtained  by 
bronchoscopic  protected-specimen-brush  sampling  but  at  a 
significantly  lower  cost.  The  culture  threshold  we  used  for 
the  mini-BAL  culture  specimens  was  10'  cfu/mL.  This  is  lower 
than  that  used  for  standard  B  AL;  however,  its  diagnostic  ac- 
curacy has  been  validated  using  postmortem  lung  examina- 
tion and  tissue  cultures.82 

Similar  to  cultures  of  endotracheal  aspirates,  blind  mini- 
BAL  identifies  more  organisms  than  do  bronchoscopic  sam- 
pling methods  (eg.  protected  specimen  brush  or  BAL).83  This 
could  potentially  increase  the  costs  associated  with  this  less 
specific  diagnostic  technique  due  to  the  possible  need  for 
additional  antibiotics  to  treat  all  identified  organisms.  How- 
ever, at  least  one  investigation  has  suggested  that  these  non- 
bronchoscopic methods  can  allow  serial  evaluations  to  be 
readily  performed  in  patients  requiring  prolonged  mechanical 
ventilation  in  order  to  allow  early  specific  diagnosis  and  treat- 
ment of  VAP.84  This  has  resulted  in  the  successful  withholding 
of  antibiotics  in  patients  with  suspected  VAP  who  had  neg- 
ative mini-BAL  cultures  and  would  otherwise  have  been  treat- 
ed on  the  basis  of  clinical  criteria  alone.84  If  these  results  are 
validated,  then  such  nonbronchoscopic  techniques  could  make 
follow-up  evaluations  of  persistent  or  new  infiltrates  (due 


to  possible  superinfection)  easier  and  more  cost-effective 
to  perform. 

Although  data  supporting  the  efficacy  of  using  invasive 
bronchoscopic  and  nonbronchoscopic  diagnostic  methods 
over  empiric  treatment  of  VAP  are  lacking,  the  potential  dan- 
gers associated  with  the  unnecessary  administration  of  an- 
tibiotics (eg,  emergence  of  antibiotic-resistant  infections)1011 
and  concents  over  the  inappropriate  selection  of  antibiotics58 
have  been  given  as  justification  for  their  application  at  pre- 
sent.85 Further  resolution  of  the  controversy  regarding  the  need 
for  lower  airway  sampling  in  patients  with  suspected  VAP 
awaits  prospective  clinical  trials  aimed  at  validating  these 
diagnostic  methods  using  appropriate  patient  outcomes.  Until 
such  data  become  available,  individual  institutions  should 
tailor  their  strategies  for  the  evaluation  of  VAP  according 
to  local  expertise  and  review  of  the  prevailing  opinions  re- 
garding this  issue.76-85"87 

Figure  2  offers  our  approach  to  the  evaluation  and  treat- 
ment of  suspected  VAP  using  either  bronchoscopic  or  non- 
bronchoscopic lower  airway  sampling  techniques.  Other  ap- 
proaches using  only  clinical  criteria  as  determinants  for  an- 
tibiotic treatment  could  also  be  designed  and  successfully 


/     specimen:      \ 

V       Significant      / 

\^    colony      X 

1 

1 

spectrum  antibiotic 
possible 

Clinically 
improved 

Suspicion  tor  VAP 
persists 

i 

i 

Observe  off 

Repeat  LflT 
sampling 

Fig.  2.  Flow  chart  showing  management  strategy  for  patients  with 
suspected  ventilator-associated  pneumonia  (VAP).  LRT  =  lower 
respiratory  tract. 


34 


Respiratory  Care  •  NOVEMBER  '95  Vol  40  No  1 1 


Ventilator-Associated  Pneumonia 


implemented.  In  designing  such  a  strategy,  it  is  important  to 
note  that  the  use  of  clinical  criteria  alone  for  the  diagnosis  of 
VAP  (ie,  not  requiring  invasive  diagnostic  methods)  can  be 
employed  for  both  'high-quality'  patient  care  and  clinical  in- 
vestigation.76 Additionally,  a  Clinical  Pulmonary  Infection 
Score  (CPIS)  has  been  developed  to  aid  in  the  bedside  diagnosis 
of  VAP.88  The  CPIS  correlates  well  with  the  results  of  quan- 
titative bacteriologic  results  obtained  with  BAL.84-88 

Prevention  &  Treatment 

Few  specific  approaches  to  the  prevention  of  VAP  have 
been  evaluated  in  a  rigorous  fashion.  As  a  result,  many  ther- 
apeutic strategies  are  controversial.  To  make  the  basis  of  our 
own  recommendations  explicit,  we  have  graded  them  according 
to  the  quality  of  the  currently  available  scientific  information 
(Tables  2  &  3).  In  the  absence  of  specific  clinical  trials,  we 
offer  our  own  approach,  recognizing  the  often  controversial 
nature  of  various  strategies. 

Table  2.      The  Quality  of  the  Evidence  and  the  Grading  of 
Recommendations  in  VAP 

Quality  of  the  evidence 

Level  1:  randomized,  prospective,  controlled  investigation  of 

VAP 

Level  2:  nonrandomized  concurrent-cohort  investigations,  his- 

torical-cohort investigations,  and  case  series  of  VAP 

Level  3:  randomized,  prospective,  controlled  investigations  of 

other  nosocomial  infections  with  potential  application 
to  VAP 

Level  4:  case  reports  of  VAP 

Grading  of  recommendations 

A:  Supported  by  at  least  two  Level- 1  investigations 

B:  Supported  by  at  least  one  Level- 1  investigation 

C:  Supported  by  Level-2  investigations  only 

D:  Supported  by  at  least  one  Level-3  investigation 

Ungraded:        No  available  clinical  investigations 


(ie.  SIRS,  sepsis,  severe  sepsis,  septic  shock,  and  end-organ 
dysfunction)  may  allow  more  specific  guidelines  to  be  de- 
veloped for  empiric  administration  of  antimicrobial  therapy 
in  the  ICU  setting.94-95 

Table  3.      Recommendations  for  the  Prevention  of  Ventilator- 
Associated  Pneumonia 


Treatment 


Recommended   Grade*    Reference 


Nonpharmacologic 
Effective  hand  washing 
Use  of  protective  gowns  and  gloves 
Semi-erect  positioning 
Avoid  large  gastric  volumes 
Oral  (non-nasal)  intubation 
Routine  drainage  of  ventilator- 
circuit  condensate 
Routine  ventilator-circuit  changes 
Use  of  heat  &  moisture  exchangers 
Continuous  subglottic  suctioning 
Postural  oscillation/rotation 
Use  of  a  quality  improvement  team 

Pharmacologic 
Avoid  routine  stress  ulcer 

prophylaxis 
Administration  of  sucralfate  to 

high-risk  patients  for  stress 

ulcer  prophylaxis 
Avoid  unnecessary  empiric 

antimicrobial  administration 
Aerosolized  prophylactic  antibiotics 
Selective  digestive  decontamination 
Prophylactic  standard  immune 

globulin 
Prophylactic  GCSF  &  antibiotics 

in  neutropenic  patients 


Yes 

B 

96 

Yes* 

B 

98 

Yes 

C 

11,15 

Yes 

B 

16,17 

Yes 

D 

39 

Yes 

C 

106 

No 

A 

107-110 

Yes 

B 

110 

Yes 

A 

103.104 

Yes*' 

B 

113-115 

Yes 

C 

33 

52,53 


Yes 

C 

10,11 

No 

B 

26,89,90 

No 

A 

27,91,92 

Yes" 

D 

112 

Yes' 

D 

117-119 

*Refers  to  grading  scheme  in  Table  2.  'Recommended  in  selected  patients 
described  in  the  investigation.  -Pending  the  results  of  further  clinical  trials;  H-2  = 
histamine  type-2  receptor;  GCSF  =  granulocyte  colony-stimulating  factor. 


VAP  =  ventilator-associated  pn 


Direct  topical  administration  of  antibiotics  into  the  airway 
has  been  examined  in  an  attempt  to  provide  prophylaxis  against 
the  development  of  VAP  in  high-risk  patients.  The  evidence 
to  date  suggests  that  this  practice  does  not  improve  patient 
outcome  and  is  associated  with  the  development  of  nosoco- 
mial pneumonia  due  to  antibiotic-resistant  bacteria.26-89-90  Sim- 
ilarly, the  routine  application  of  SDD,  with  or  without  the  ad- 
ministration of  systemic  antibiotic  prophylaxis,  has  not  been 
shown  to  improve  patient  outcome  despite  evidence  suggesting 
that  the  overall  incidence  of  VAP  is  reduced  by  its  admin- 
istration.91 93  We  recommend  that  the  unnecessary  use  of  all 
antibiotics,  particularly  broad-spectrum  agents,  be  avoided 
unless  clear  indications  for  their  use  are  present.  Future  in- 
vestigations employing  new  clinical  criteria,  such  as  the  sys- 
temic inflammatory  response  syndrome  (SIRS)  classification 


Most  current  recommendations  for  the  prevention  of  VAP 
rely  on  methods  aimed  at  minimizing  colonization  of  patients 
with  pathogenic  bacteria  and  avoiding  the  occurrence  of  as- 
piration events.  Caregiver  handwashing96  and  the  appropri- 
ate use  of  gloves  or  barrier  precautions,97-98  maintaining  the 
patient  in  the  semirecumbent  position,15  and  avoiding  of  gas- 
tric overdistension,1617-99  all  appear  to  be  reasonable  meth- 
ods that  can  be  readily  applied  (Table  3).  Avoidance  of  gas- 
tric alkalinization  (with  histamine  type-2-receptor  antagonists 
and  antacids),  unless  indicated  in  high-risk  patients,  also  ap- 
pears to  be  a  reasonable  and  cost-effective  preventive  strat- 
egy based  on  current  clinical  data.1-1-14-51"53  However,  when 
prophylaxis  against  gastrointestinal  stress  ulceration  is  required, 
several  recent  meta-analyses  have  suggested  that  sucralfate 
is  associated  with  significantly  less  development  of  VAP  com- 
pared to  either  antacids  or  histamine  type-2-receptor  antag- 
onists."*102 Additionally,  one  of  these  analyses  also  suggested 


Respiratory  Care  •  November  '95  Vol  40  No  1 


1135 


YIN  I II  ATOR-ASSOCIATED  PNEUMONIA 


a  surv  ival  advantage  with  the  use  of  sucralfate  compared  to 
the  gastric-pH-lowering  agents.102 

Recently,  continuous  suctioning  of  subglottic  secretions 
using  a  modified  endotracheal  tube  has  been  shown  to  pre- 
vent the  occurrence  of  early-onset  VAP  (ie.  VAP  occurring 
within  4  to  5  days  of  intubation).103,104  Despite  preventing  the 
development  of  early-onset  nosocomial  pneumonia,  which 
is  usually  due  to  low-risk  antibiotic-sensitive  pathogens,  there 
was  no  reduction  in  overall  mortality  with  this  intervention. 
These  investigations,  along  with  the  trials  of  SDD  (which  also 
primarily  prevent  early-onset  VAP).  emphasize  the  need  for 
strategies  directed  tow  aid  preventing  the  development  of  VAP 
occurring  later  in  the  course  of  mechanical  ventilation.  Such 
strategies  would  have  a  greater  likelihood  of  improving  pa- 
tient outcome  because  it  is  late-onset  VAP  that  typically  is 
due  to  high-risk  antibiotic-resistant  pathogens  associated  with 
a  higher  mortality.10,31-51'105 

Regular  monitoring  of  ventilator  circuits  for  the  removal 
of  accumulated  condensate  is  another  important  preventive 
strategy  due  to  the  high  concentration  of  bacteria  present  in 
these  pools  of  fluid.""1  However,  changing  ventilator  circuits 
too  often  can  increase  the  occurrence  of  VAP.  This  is  thought 
to  occur  due  to  increased  manipulation  of  the  patient,  the  en- 
dotracheal tube,  or  the  ventilator  circuit  resulting  in  increased 
aspiration  of  contaminated  tubing  condensate  or  upper  air- 
way secretions.4  us  Our  group  has  recently  demonstrated  in 
a  prospective,  randomized,  controlled  trial  that  the  elimina- 
tion of  routine  ventilator-circuit  changes  is  associated  with 
significant  cost  savings  and  does  not  increase  the  incidence 
of  nosocomial  pneumonia  in  patients  requiring  prolonged  me- 
chanical ventilation.107  This  study  supports  the  findings  of  other 
investigators1"8""  and  should  allow  more  specific  recom- 
mendations to  be  made  regarding  the  lack  of  need  for  routine 
ventilator  circuit  changes. ' ' ' 

Different  humidification  techniques  have  also  been  eval- 
uated in  terms  of  their  relationship  to  the  occurrence  of  VAP. 
Most  active  humidification  methods  (Cascade-type  humid- 
ification, wick  humidifiers)  allow  condensate  to  develop  with- 
in ventilator  circuits,  which  quickly  becomes  colonized  with 
pathogenic  bacteria.18  Passive  humidification  using  heat  and 
moisture  exchangers  (HMEs)  allows  airway  humidification 
to  occur  without  condensate  formation.  Additionally,  many 
HMKs  can  filter  out  pathogens  reducing  the  colonization  of 
ventilator  circuits.""  However,  reductions  in  ventilator  cir- 
cuit colonization  with  the  use  of  HMEs  has  not  been  shown 
to  reduce  the  occurrence  of  VAP.""  This  suggests  that  cir- 
cuit colonization  plays  little  or  no  role  in  the  development  of 
VAP.  provided  usual  precautions  are  applied  to  prevent  as- 
piration of  contaminated  condensate  (eg.  regular  emptying 
of  condensate  collection  traps,  semirecumbent  positioning, 
avoidance  of  unnecessary  circuit  manipulation).  However. 
the  use  of  I  IMHs  may  still  be  beneficial  by  reducing  the  amount 
oi  time  spent  performing  potentially  unnecessary  procedures 
(eg.  emptying  ol  ventilator  circuit  traps)  related  to  the  use  of 


active  humidification  methods.  Similar  benefits  have  been  re- 
ported for  heated  wire  circuits. 

Other  strategies  investigated  for  the  possible  prevention 
of  VAP  include  the  use  of  oral  as  opposed  to  nasal  intuba- 
tion (avoidance  of  nosocomial  sinusitis,  which  is  associat- 
ed with  the  occurrence  of  VAP).'1'  implementation  of  for- 
mal quality  improvement  programs  to  reduce  the  occurence 
of  VAP,"  the  administration  of  standard  immune  globulin 
to  high-risk  postsurgical  patients."-1  and  the  application  of 
rotating  bed  therapy  or  postural  oscillation  in  selected  sub- 
groups of  patients."3"5  However,  immune  globulin,  rotating 
bed  therapy  and  postural  oscillation  still  represent  investi- 
gational techniques  requiring  further  clinical  investigation 
before  more  definitive  recommendations  regarding  their  use 
can  be  made  (Table  3).  It  is  our  practice  at  present  not  to  em- 
ploy these  techniques  routinely  but  instead  to  ensure  that  pa- 
tients are  kept  in  a  semirecumbent  position  and  to  employ 
good  infection-control  policies  to  prevent  aspiration  of  col- 
onized secretions  or  ventilator  condensate. ' l6  Additionally, 
serious  nosocomial  infections  including  VAP  can  be  prevented 
in  neutropenic  patients  by  the  prophylactic  administration 
of  antibiotics  and  granulocyte  colony-stimulating  factor."7"9 
In  these  severely  immunosuppressed  patients,  the  benefits 
of  broad-spectrum  antimicrobial  therapy  clearly  outweigh 
any  risk  associated  with  the  use  of  these  agents  until  neu- 
trophil recovery  occurs."9 

When  preventive  measures  fail  and  VAP  develops,  then 
its  effective  treatment  requires  an  appropriate  course  of  an- 
timicrobial therapy  once  the  diagnosis  is  established."612" The 
narrowest  spectrum  of  antibiotics  possible  should  be  used  when 
the  etiologic  agent(s)  for  VAP  are  known.  The  appropriate 
use  of  antibiotics  (eg,  adequate  dosing,  appropriate  suscep- 
tibility of  the  causal  organisms)  appears  to  significantly  in- 
fluence the  outcome  of  patients  with  VAP.,l:l  Therefore,  ef- 
forts should  be  made  to  establish  the  cause  of  VAP  in  most 
circumstances  so  as  to  optimize  therapeutic  interventions. 

In  Summary 

VAP  is  a  common  problem  faced  by  clinicians  caring  for 
critically  ill  patients.  Use  of  appropriate  preventive,  diagnostic, 
and  therapeutic  strategies  should  minimize  morbidity  resulting 
from  this  clinical  problem.  Future  investigations  need  to  bet- 
ter define  the  optimum  diagnostic  methods  and  the  most  ap- 
propriate use  of  antibiotics  for  patients  with  suspected  VAP. 
Only  by  developing  these  strategies  can  we  hope  to  avoid  the 
complications  associated  with  spiraling  empiricism. i::  These 
complications  include  numerous  outbreaks  of  serious  antibiotic- 
resistant  nosocomial  infections  due  to  the  empiric  over-ad- 
ministration of  broad-spectrum  antimicrobial  agents.  Advances 
in  both  the  clinical  and  basic  medical  sciences  are  likely  to 
help  further  elucidate  the  epidemiology  and  pathogenesis  of 
VAP  and.  therein .  improve  the  opportunities  for  future  pre- 
vention of  this  disorder. 


16 


Respiratory  Care  •  November  '95  Vol.  40  No  1 1 


Ventilator-Associated  Pneumonia 


ACKNOWLEDGMENT 

We  thank  Cindy  Brame  for  her  secretarial  assistance. 

REFERENCES 

1.  Craven  DE,  Steger  KA.  Barber  TW.  Preventing  nosocomial  pneu- 
monia: state  of  the  art  and  perspectives  for  the  1990s.  Am  J  Med 
]  99 1  ;9 1  ( 3.  PartB):44S-53S. 

2.  Fagon  JY.  Chastre  J,  Domart  Y,  Trouillet  JL.  Pierre  J.  Dame  C,  Gib- 
ert  C.  Nosocomial  pneumonia  in  patients  receiving  continuous  me- 
chanical ventilation.  Prospective  analysis  of  52  episodes  with  use  of 
a  protected  specimen  brush  and  quantitative  culture  technique.  Am 
RevRespirDis  1989;  139(41:877-884. 

3.  Torres  A,  Aznar  R.  Gatell  JM,  Jimenez  P.  Gonzalez  J,  Ferrer  A.  et 
al.  Incidence,  risk,  and  prognosis  factors  of  nosocomial  pneumonia 
in  mechanically  ventilated  patients.  Am  Rev  Respir  Dis  1990:142 
(3):523-528. 

4.  Craven  DE.  Kunches  LM.  Kilinsky  V,  Lichtenberg  DA.  Make  BJ. 
McCabe  WR.  Risk  factors  for  pneumonia  and  fatality  in  patients  re- 
ceiving continuous  mechanical  ventilation.  Am  Rev  Respir  Dis 
1986:133(51:792-796. 

5.  Craven  DE.  Kunches  LM.  Lichtenberg  DA.  Kollisch  NR.  Barry  MA. 
Heeren  TC.  McCabe  WR.  Nosocomial  infection  and  fatality  in  med- 
ical and  surgical  intensive  care  unit  patients.  Arch  Intern  Med 
1988:148(51:1161-1168. 

6.  Celis  R,  Torres  A.  Gatell  JM.  Almela  M,  Rodriguez-Roisin  R.  Agusti- 
Vidal  A.  Nosocomial  pneumonia.  A  multivariate  analysis  of  risk  and 
prognosis.  Chest  1988:93(2):318-324. 

7.  Leu  HS,  Kaiser  DL.  Mori  M,  Woolson  RF,  Wenzel  RP.  Hospital- 
acquired  pneumonia.  Attributable  mortality  and  morbidity.  Am  J  Epi- 
demiol 1989;129(6):1258-1267. 

8.  Meduri  GU.  Johanson  WG  Jr.  International  consensus  conference: 
clinical  investigation  of  ventilator-associated  pneumonia.  Chest 
1992;102(5,  Suppl):551S-552S. 

9.  Fagon  JY.  Chastre  J.  Hance  AJ.  Montravers  P.  Novara  A,  Gibert  C. 
Nosocomial  pneumonia  in  ventilated  patients:  a  cohort  study  eval- 
uating attributable  mortality  and  hospital  stay.  Am  J  Med  1993:94 
(3):281-288. 

10.  Rello  J.  Ausina  V,  Ricart  M.Castella  J.  Prats  G.  Impact  of  previous 
antimicrobial  therapy  on  the  etiology  and  outcome  of  ventilator-as- 
sociated pneumonia.  Chest  1 993;  1 04(  1 6 ):  1 230- 1 235. 

1 1 .  Kollef  MH.  Ventilator-associated  pneumonia:  a  multivariate  anal- 
ysis. JAMA  1993;270(16):1965-1970. 

12.  Jimenez  P.  Torres  A.  Rodriguez-Roisin  R.  de  la  Bellacasa  JP,  Aznar  R, 
Gatell  JM,  Agusti-Vidal  A.  Incidence  and  etiology  of  pneumonia 
acquired  during  mechanical  ventilation.  CritCare  Med  1989;  17(9): 
882-885. 

1 3.  Driks  MR.  Craven  DE,  Celli  BR,  Manning  M.  Burke  RA,  Garvin  GM. 
et  al.  Nosocomial  pneumonia  in  intubated  patients  given  sucralfate 
as  compared  with  antacids  or  histamine  type  2  blockers.  The  role  of 
gastric  colinization.  N  Engl  J  Med  1987:317(221:1376-1382. 

14.  Tryba  M.  Risk  of  acute  stress  bleeding  and  nosocomial  pneumonia 
in  ventilated  intensive  care  unit  patients:  sucralfate  versus  antacids. 
Am  J  Med  1987:83(3,  Suppl):l  17-124. 

15.  Torres  A.  Serra-Batlles  J,  Ros  E.  Piera  C.  de  la  Bellacasa  JP.  Cobos  A. 
et  al.  Pulmonary  aspiration  of  gastric  contents  in  patients  receiving 
mechanical  ventilation:  the  effect  of  body  position.  Ann  Intern  Med 
1992:116(71:540-543. 

1 6.  Montecalvo  MA.  Steger  KA.  Farber  HW.  Smith  BF.  Dennis  RC,  Fitz- 
patrick  GF,  et  al.  Nutritional  outcome  and  pneumonia  in  critical  care 
patients  randomized  to  gastric  versus  jejunal  tube  feedings.  Crit  Care 
Med  1992;20(10):  1377-1387. 

17.  Marian  M.  Rappaport  W,  Cunningham  D.  Thompson  C,  Esser  M, 


Williams  F,  Warneke  J.  Hunter  G.  The  failure  of  conventional  meth- 
ods to  promote  spontaneous  transpyloric  feeding  tube  passage  and 
the  safety  of  intragastric  feeding  in  the  critically  ill  ventilated  patient. 
Surg  Gynecol  Obstet  1993;  176(5 1:475-479. 
Craven  DE.  Connolly  MG  Jr.  Lichtenberg  DA,  Primeau  PJ.  Mc- 
Cabe WR.  Contamination  of  mechanical  ventilators  with  nibing  changes 
every  24  or  48  hours.  N  Engl  J  Med  1982:306(25)  1505-1509. 
Meyer  KS,  Urban  C.  Eagan  JA.  Berger  BJ.  Rahal  JJ.  Nosocomial 
outbreak  of  klebsiella  infection  resistant  to  late-generation  cepha- 
losporins. Ann  Intern  Med  1993;1 19(5):353-358. 
Chow  JW.  Fine  MJ.  Shlaes  DM.  Quinn  JP.  Hooper  DC,  Johnson  MP, 
et  al.  Enterobacter  bacteremia:  clinical  features  and  emergence  of 
antibiotic  resistance  during  therapy.  Ann  Intern  Med  1991:1 15(8): 
585-590. 

Struelens  MJ,  Carlier  E,  Maes  N,  Seiruys  E.  Quint  WG.  van  Belkum  A. 
Nosocomial  colonization  and  infection  with  multiresistant  Acine- 
tobacter baunumnii:  outbreak  delineation  using  DNA  macrorestriction 
analysis  and  PCR-fingerprinting.  J  Hosp  Infect  1993;25(  1 ):  15-32. 
Rello  J,  Ausina  V,  Ricart  M,  Puzo  C,  Quintana  E.  Net  A.  Prats  G. 
Risk  factors  for  infection  by  Pseudomonas  aeruginosa  in  patients 
with  ventilator-associated  pneumonia.  Intensive  Care  Med  1994:20 
(31:193-198. 

Kollef  MH.  Wragge  T.  Pasque  C.  Determinants  of  multiorgan  dys- 
function in  cardiac  surgery  patients  requiring  prolonged  mechani- 
cal ventilation.  Chest  1 995;  1 07(5 ):  1 395- 1 40 1 . 
Rello  J.  Torres  A.  Ricart  M,  Valles  J.  Gonzalez  J,  Artigas  A.  Rodriguez- 
Roisin  R.  Ventilator-associated  pneumonia  by  Staphylococcus  au- 
reus. Comparison  of  methicillin-resistant  and  methicillin-sensitive 
episodes.  Am  J  Respir  Crit  Care  Med  1994;150:1545-1549. 
Rello  J,  Ricart  M.  Ausina  V.  Net  A.  Prats  G.  Pneumonia  due  to 
Haemophilus  influenzae  among  mechanically  ventilated  patients.  In- 
cidence, outcome,  and  risk  factors.  Chest  1992;  102(5):  1562-1565. 
Klick  JM.  duMoulin  CC,  Hedley-Whyte  J,  Teres  C.  Bushnell  LS, 
Feingold  DS.  Prevention  of  gram-negative  bacillary  pneumonia  using 
polymyxin  aerosol  as  prophylaxis.  II.  Effect  on  the  incidence  of  pneu- 
monia in  seriously  ill  patients.  J  Clin  Invest  1975;55(3):514-519. 
Gastinne  H,  Wolff  M,  Delatour  F,  Faurisson  F.  Chevret  S.  The  French 
Study  Group  on  Selective  Decontamination  of  the  Digestive  Tract. 
A  controlled  trial  in  intensive  care  units  of  selective  decontamina- 
tion of  the  digestive  tract  with  nonabsorbable  antibiotics.  N  Engl  J  Med 
1992;326(9):594-599. 

Daschner  F.  Emergence  of  resistance  during  selective  decontami- 
nation of  the  digestive  tract.  Eur  J  Clin  Microbiol  Infect  Dis  1992:1 1 
(l):l-3. 

Bonten  MJ.  van  Tiel  FH,  van  der  Geest  S.  Stobberingh  EE.  Gail- 
lard  CA.  Enterococcusfaecalis  pneumonia  complicating  topical  an- 
timicrobial prophylaxis.  N  Engl  J  Med  1993:328(31:209-210. 
Nau  R,  Ruchel  R.  Mergerian  H.  Wegener  U,  Winkelmann  T, 
Prange  HW.  Emergence  of  antibiotic-resistant  bacteria  during  selective 
decontamination  of  the  digestive  tract.  J  Antimicrob  Chemother 
1990:25(5  ):88 1-883. 

Kollef  MH,  Silver  P.  Murphy  DM.  Trovillion  E.  The  effect  of  late- 
onset  ventilator-associated  pneumonia  in  determining  patient  mor- 
tality. Chest  (1995.  in  Press). 

Boyce  JM.  Potter-Bynoe  G.  Dziobek  L.  Solomon  SL.  Nosocomial 
pneumonia  in  Medicare  patients.  Hospital  costs  and  reimbursement 
patterns  under  the  prospective  payment  system.  Arch  Intern  Med 
1991:151(61:1 109-1 114. 

Kelleghan  SI.  Salemi  C,  Padilla  S.  McCord  M.  Mermilliod  G. 
Canola  T,  Becker  L.  An  effective  continuous  quality  improvement 
approach  to  the  prevention  of  ventilator-associated  pneumonia.  Am 
J  Infect  Control  1993:21(61:322-330. 

Fiddian-Green  RG,  Baker  S.  Nosocomial  pneumonia  in  the  critically 
ill:  product  of  aspiration  or  translocation?  Crit  Care  Med  1991:19 
(6):763-769. 


Respiratory  Care  •  November  '95  Vol  40  No 


137 


Ventilator-Associated  Pneumonia 


35.  Huxley  EJ.  Viroslav  J.  Gray  WR.  Pierce  AK.  Pharyngeal  aspiration 
in  normal  adults  and  patients  with  depressed  consciousness.  Am  J  Med 
l978;64(4):564-568. 

36.  lohanson  WG  Jr.  Seidenfeld  JJ.  de  los  Santos  R.  Coalson  JJ.  Gomez  P. 
Prevention  of  nosocomial  pneumonia  using  topical  and  parenteral 
antimicrobial  agents.  Am  Rev  RespirDis  1988;137(2):265-272. 

37.  Berendl  RF.  Relationship  of  method  of  administration  to  respiratory 
virulence  of  Klebsiella  pneumoniae  for  mice  and  squirrel  monkeys. 
Infect  Immun  1978;20(2):58 1-583. 

38.  Greene  R.  Thompson  S.  Jantsch  HS.  Teplick  R.  Cullen  DJ.  Greene  EM. 
Whitman  GJ,  Hulka  CA,  Llewellyn  HJ.  Detection  of  pooled  secre- 
tions above  endotracheal-tube  cuffs:  value  of  plain  radiographs  in 
sheep  cadavers  and  patients.  AJR  1994;163:1333-1337. 

39.  Rouby  JJ,  Laurent  P.  Gosnach  M.  Cambau  E.  Lamas  G,  Zouaoui  A, 
et  al.  Risk  factors  and  clinical  relevance  of  nosocomial  maxillary  si- 
nusitis in  the  critically  ill.  Am  J  Respir  Crit  Care  Med  1994:150(3): 
776-783. 

40.  Heffner  JE.  Nosocomial  sinusitis.  Den  of  multiresistant  thieves?  Am 
J  Respir  Crit  Care  Med  1994;150(3):608-609. 

41.  Scannapieco  FA,  Stewart  EM,  Mylotte  JM.  Colonization  of  dental 
plaque  by  respiratory  pathogens  in  medical  intensive  care  patients. 
Crit  Care  Med  1992:20(61:740-745. 

42.  Heyland  D,  Mandell  LA.  Gastric  colonization  by  gram-negative  bacil- 
li and  nosocomial  pneumonia  in  the  intensive  care  unit  patient.  Ev- 
idence for  causation.  Chest  1 992;  101  ( 1  >:  1 87- 1 93. 

43.  Giannella  RA,  Broitman  SA.  Zamcheck  N.  Influence  of  gastric  acid- 
ity on  bacterial  and  parasitic  enteric  infections.  A  perspective.  Ann 
Intern  Med  1973:78(21:271-276. 

44.  Donowitz  LG,  Page  MC,  Mileur  GL.  Guenthner  SH.  Alteration  of 
normal  gastric  flora  in  critical  care  patients  receiving  antacid  and  cime- 
tidine  therapy.  Infect  Control  1986:7(1  ):23-26. 

45.  DuMoulin  GC.  Paterson  DG.  Hedley-Whyte  J,  Lisbon  A.  Aspiration 
of  gastric  bacteria  in  antacid-treated  patients:  a  frequent  cause  of  post- 
operative colonization  of  the  airway.  Lancet  1982:1(82661:242-245. 

46.  George  DL.  Epidemiology  of  nosocomial  pneumonia  in  intensive 
care  unit  patients.  Clin  Chest  Med  1995;16(  1  ):29-44. 

47.  Craven  DE.  Steger  KA.  Epidemiology  of  nosocomial  pneumonia. 
New  perspectives  on  an  old  disease.  Chest  1995;108:1S-16S. 

48.  Noseworthy  TW,  Cook  DJ.  Nosocomial  pneumonia,  prophylaxis 
against  gastric  erosive  disease,  and  clinically  important  gastrointestinal 
bleeding:  where  do  we  stand?  Crit  Care  Med  1993;21(  12):1814-1816. 

49.  Pickworth  KK,  Falcone  RE,  Hoogeboom  JE.  Santanello  SA.  Oc- 
currence of  nosocomial  pneumonia  in  mechanically  ventilated  trau- 
ma patients:  a  comparison  of  sucralfate  and  ranitidine.  Crit  Care  Med 
1993;21(12):1856-1862. 

50.  Metz  CA,  Livingston  DH,  Smith  JS.  Larson  GM,  Wilson  TH.  Im- 
pact of  multiple  risk  factors  and  ranitidine  prophylaxis  on  the  de- 
velopment of  stress-related  upper  gastrointestinal  bleeding:  a  prospec- 
tive, multicenter.  double-blind,  randomized  trial.  Crit  Care  Med 
1993;21(12):I844-1849. 

51.  Prod'hom  G,  Leuenberger  P.  Koerfer  J,  Blum  A.  Chiolero  R, 
Schaller  MD.  ct  al.  Nosocomial  pneumonia  in  mechanically  venti- 
lated patients  receiving  antacid,  ranitidine,  or  sucralfate  as  prophylaxis 
for  stress  ulcer:  a  randomized  controlled  trial.  Ann  Intern  Med 
1994;120(8):653-662. 

52.  Ben-Menachem  T.  Fogel  R.  Patel  RV,  Touchette  M.  Zarowitz  BJ. 
Hadzijahic  N,  et  al.  Prophylaxis  for  stress-related  gastric  hemorrhage 
in  the  medical  intensive  care  unit.  A  randomized,  controlled,  single- 
blind  study.  Ann  Intern  Med  1994;121(8):568-575. 

53.  Canadian  Critical  Care  Trials  Group.  Cook  DJ,  Fuller  HD.  Guy- 
atlGII.  Marshall  JC,  Leasa  I).  Hall  R,  et  al  Risk  factors  lor  gas- 
trointestinal bleeding  in  critically  ill  patients.  N  Engl  J  Med  1994 
(6);330;  377-3X1. 

54.  Meduri  GU.  Venlilatoi  -associated  pneumonia  in  patients  with  res- 
piratoiy  failure.  A  diagnostic  approach.  Chest  1990;97(5):  1208-1219. 


56 


57 


Meduri  GU.  Diagnosis  and  differential  diagnosis  of  ventilator-as- 
sociated pneumonia.  Clin  Chest  Med  1995;16(  1 1:61-93. 
Andrews  CP,  Coalson  JJ.  Smith  JD.  Johanson  WG  Jr.  Diagnosis  of 
nosocomial  bacterial  pneumonia  in  acute,  diffuse  lung  injury.  Chest 
1981:80(31:254-258. 

Fagon  JY,  Chastre  J,  Hance  AJ,  Guiguet  M.  Trouillet  JL,  Domart  Y. 
Pierre  J,  Gibert  C.  Detection  of  nosocomial  lung  infection  in  ven- 
tilated patients.  Use  of  a  protected  specimen  brush  and  quantitative 
culture  techniques  in  147  patients.  Am  Rev  Respir  Dis  1988:138 
(11:110-116. 

58.  Fagon  JY,  Chastre  J,  Hance  AJ,  Domart  Y.  Trouillet  JL,  Gibert  C. 
Evaluation  of  clinical  judgement  in  the  identification  and  treatment 
of  nosocomial  pneumonia  in  ventilated  patients.  Chest  1993:103 
(2):547-553. 

59.  Rubin  SA.  Winer-Muram  HT.  Ellis  J  V.  Diagnostic  imaging  of  pneu- 
monia and  its  complications  in  the  critically  ill  patient.  Clin  Chest 
Med  1995:16(1  ):45-59. 

Wunderink  RG.  Woldenberg  LS,  Zeiss  J,  Day  CM,  Ciemins  J,  Lach- 
er  DA.  The  radiologic  diagnosis  of  autopsy-proven  ventilator-associated 
pneumonia.  Chest  1992;101(2):458-463. 

Leeper  KV  Jr.  Diagnosis  and  treatment  of  pulmonary  infections 
in  adult  respiratory  distress  syndrome.  New  Horizons  1993:1(4): 
550-562. 

Fagon  JY,  Chastre  J.  Trouillet  JL,  Domart  Y,  Dombret  MC.  Bomet  M. 
Gibert  C.  Characterization  of  distal  bronchial  microflora  during  acute 
exacerbation  of  chronic  bronchitis.  Use  of  the  protected  specimen 
brush  technique  in  54  mechanically  ventilated  patients.  Am  Rev  Respir 
Dis  1990;142(5):1004-1008. 

Salata  RA.  Lederman  MM.  Shlaes  DM.  Jacobs  MR.  Eckstein  E. 
Tweardy  D,  et  al.  Diagnosis  of  nosocomial  pneumonia  in  intubat- 
ed, intensive  care  unit  patients.  Am  Rev  Respir  Dis  1987:135(2): 
426-432. 

Shlaes  DM,  Lederman  MM,  Chmielewski  R.  Tweardy  D.  Krause  G, 
Saffai  C.  Sputum  elastin  fibers  and  the  diagnosis  of  necrotizing  pneu- 
monia. Chest  1984;85(6):763-766. 

Marquette  CH.  Georges  H,  Wallet  F,  Ramon  P,  Saulnier  F.  Nevierre  R, 
et  al.  Diagnostic  efficiency  of  endotracheal  aspirates  with  quantitative 
bacterial  cultures  in  intubated  patients  with  suspected  pneumonia. 
Comparison  with  the  protected  specimen  brush.  Am  Rev  Respir  Dis 
1993;148(1):138-144. 

el-Ebiary  M.  Torres  A,  Gonzalez  J,  de  la  Bellacasa  JP.  Garcia  C. 
Jimenez  de  Anta  MT.  et  al.  Quantitative  cultures  of  endotracheal  as- 
pirates for  the  diagnosis  of  ventilator-associated  pneumonia.  Am  Rev 
RespirDis  1993;  148(6,  Part  11:1552-1557. 

Marquette  CH.  Copin  MC.  Wallet  F,  Neviere  R.  Saulnier  F.  Math- 
ieu  D.  et  al.  Diagnostic  tests  for  pneumonia  in  ventilated  patients: 
prospective  evaluation  of  diagnostic  accuracy  using  histology  as  a 
diagnostic  gold  standard.  Am  J  RespirCrit  Care  Med  1995:151(6): 
1878-1888. 

Wunderink  RG.  Russell  GB,  Mezger  E,  Adams  D,  Popovich  J  Jr.  The 
diagnostic  utility  of  antibody  coated  bacteria  test  in  intubated  patients. 
Chest  1991;99(l):84-88. 

Wimberley  N.  Faling  U,  Bartlett  JG.  A  fiberoptic  bronchoscopy  tech- 
nique to  obtain  uncontaminated  lower  airway  secretions  for  bacte- 
rial culture.  Am  Rev  RespirDis  L979;119(3):337-343. 

70.  Chastre  J.  Viau  F,  Brun  P.  Pierre  J.  Dauge  MC.  Bouchama  A,  et  al. 
Prospective  evaluation  of  the  protected  specimen  brush  for  the  di- 
agnosis of  pulmonary  infections  in  ventilated  patients.  Am  Rev  Respir 
Dis  1984:130(51:924-929. 

Higuchi  JH.  Coalson  JJ.  Johanson  WG  Jr.  Bacterial  diagnosis  of  noso- 
comial pneumonia  in  primates.  Usefulness  of  the  protected  speci- 
men brush.  Am  Rev  Respir  Dis  1982;125(  I  ):53-57. 
Meduri  GU.  Chastre  J.  The  standardization  of  hronchoscopic  lech 
niques  for  ventilator-associated  pneumonia.  Chest  I992;102(5, 
Suppl):557S-564S. 


60 


61 


62 


63 


64 


65 


66 


67 


68 


69 


71 


138 


RESPIRATORY  ("ARE  •  NOVEMBER  '95  VOL  40  NO  I  I 


Ventilator-Associated  Pneumonia 


Baselski  VS,  El-Torky  M,  Coalson  JJ,  Griffin  JP.  The  standardiza- 
tion of  criteria  for  processing  and  interpreting  laboratory  specimens 
in  patients  with  suspected  ventilator-associated  pneumonia.  Chest 
1992:102(5,  Suppl):571S-579S. 

Chastre  J,  Fagon  JY,  Bornet-Lecso  M.  Calvat  S.  Dombret  M-C,  Al 
Khani  R,  et  al.  Evaluation  of  bronchoscopic  techniques  for  the  di- 
agnosis of  nosocomial  pneumonia.  Am  J  RespirCrit  Care  Med  1995; 
152:231-240. 

Baker  AM.  Bowton  DL,  Haponik  EF.  Decision  making  in  nosoco- 
mial pneumonia.  An  analytic  approach  to  the  interpretation  of  quan- 
titative bronchoscopic  cultures.  Chest  1995:107(1  ):85-95. 
Niederman  MS.  Torres  A.  Summer  W.  Invasive  diagnostic  testing 
is  not  needed  routinely  to  manage  suspected  ventilator-associated 
pneumonia.  Am  J  Respir  Crit  Care  Med  1994;150(2):565-569. 
Torres  A.  el-Ebiary  M,  Padro  L,  Gonzalez  J,  de  la  Bellacasa  JP, 
Ramirez  J.  et  al.  Validation  of  different  techniques  for  the  diagno- 
sis of  ventilator-associated  pneumonia.  Comparison  with  immedi- 
ate post  mortem  pulmonary  biopsy.  Am  J  Respir  Crit  Care  Med 
1994:149(2,  Pan  11:324-331. 

Dotson  RG,  Pingleton  SK.  The  effect  of  antibiotic  therapy  on  recovery 
of  intracellular  bacteria  from  bronchoalveolar  lavage  in  suspected 
ventilator-associated  nosocomial  pneumonia.  Chest  1993:103(2): 
541-546. 

Pham  LH,  Brun-Busson  C,  Legrand  P,  Rauss  A.  Verra  F,  Brochard  L, 
Lemaire  F.  Diagnosis  of  nosocomial  pneumonia  in  mechanically  ven- 
tilated patients.  Comparison  of  a  plugged  telescoping  catheter  with 
the  protected  specimen  brush.  Am  Rev  Respir  Dis  1991:143(5.  Part 
1):1055-I061. 

Papazian  L,  Martin  C,  Meric  B.  Dumon  JF.  Gouin  F.  A  reappraisal 
of  blind  bronchial  sampling  in  the  microbiologic  diagnosis  of  noso- 
comial bronchopneumonia:  a  comparative  study  in  ventilated  patients. 
Chest  1993:103(1 1:236-242. 

Leal-Noval  SR.  Alfaro-Rodriguez  E.  Murillo-Cabeza  F,  Garnacho- 
Montero  J,  Rey-Perez  J,  Munoz-Sanchez  MA.  Diagnostic  value  of 
the  blind  brush  in  mechanically  ventilated  patients  with  nosocomi- 
al pneumonia.  Intensive  Care  Med  1 992;  18(7 1:410-414. 
Rouby  JJ,  De  Lassale  EM,  Poete  P,  Nicolas  MH,  Bodin  L.  Jarlier  V, 
et  al.  Nosocomial  bronchopneumonia  in  the  critically  ill.  Histologic  and 
bacteriologic  aspects.  Am  Rev  Respir  Dis  1992:146(4):  1059-1066. 
Kollef  MH.  Bock  KR.  Richards  RD.  Heams  ML.  The  safety  and  di- 
agnostic accuracy  of  minibronchoalveolar  lavage  in  patients  with  sus- 
pected ventilator-associated  pneumonia.  Ann  Intern  Med  1995:122 
(101:743-748. 

A'Court  CH,  Garrard  CS,  Crook  D.  Bowler  I,  Conlon  C,  Peto  T.  An- 
derson E.  Microbiologic  lung  surveillance  in  mechanically  venti- 
lated patients,  using  non-directed  bronchial  lavage  and  quantitative 
culture.  Q  J  Med  1993;86(  101:635-648. 

Chastre  J,  Fagon  JY.  Invasive  diagnostic  testing  should  be  routinely 
used  to  manage  ventilated  patients  with  suspected  pneumonia.  Am 
J  Respir  Crit  Care  Med  1994;150(2):570-574. 
Cook  DJ,  Brun-Buisson  C,  Guyatt  GH.  Sibbald  WJ.  Evaluation  of 
new  diagnostic  technologies:  bronchoalveolar  lavage  and  the  di- 
agnosis of  ventilator-associated  pneumonia.  Crit  Care  Med  1994:22 
(8):1314-1322. 

Bonten  MJ,  Gaillard  CA,  Wouters  EF,  van  Tiel  FH,  Stobbenngh  EE, 
van  der  Geest  S.  Problems  in  diagnosing  nosocomial  pneumonia  in 
mechanically  ventilated  patients:  a  review.  Crit  Care  Med  1994:22 
(10):1683-1691. 

Pugin  J,  Auckenthaler  R,  Mili  N,  Janssens  JP,  Lew  PD,  Suter  PM. 
Diagnosis  of  ventilator-associated  pneumonia  by  bacteriologic  anal- 
ysis of  bronchoscopic  and  nonbronchoscopic  "blind"  bronchoalveolar 
lavage  fluid.  Am  Rev  Respir  Dis  1991:143(5,  Part  1  ):1 121-1129. 
Feeley  TW,  DuMoulin  GC,  Hedley-Whyte  J,  Bushnell  LS,  Gilbert  JP, 
Feingold  DS.  Aerosol  polymyxin  and  pneumonia  in  seriously  ill  pa- 
tients. N  Engl  J  Med  1975:293(101:471-475. 


90.  Greenfield  S,  Teres  D.  Bushnell  LS,  Hedley-Whyte  J.  Feingold  DS. 
Prevention  of  gram-negative  bacillary  pneumonia  using  aerosol 
polymyxin  as  prophylaxis.  I.  Effect  on  the  colonization  pattern  of 
the  upper  respiratory  tract  of  seriously  ill  patients.  J  Clin  Invest  1973; 
52(111:2935-2940. 

91.  Kollef  MH.  The  role  of  selective  digestive  tract  decontamination  on 
mortality  and  respiratory  tract  infections.  A  meta-analysis.  Chest 
1994;105(4):1101-1108. 

92.  Selective  Decontamination  of  the  Digestive  Tract  Trialist's  Col- 
laborative Group.  Meta-analysis  of  randomised  controlled  trials  of 
selective  decontamination  of  the  digestive  tract.  BMJ  1993:307 
(69031:525-532. 

93.  Heyland  DK,  Cook  DJ,  Jaeschke  R,  Griffith  L.  Lee  HN,  Guyatt  GH. 
Selective  decontamination  of  the  digestive  tract.  An  overview.  Chest 
1994;105(4):1221-1229. 

94.  The  American  College  of  Chest  Physicians/Society  of  Critical  Care 
Medicine  Consensus  Conference  Committee.  Bone  RC,  Balk  RA, 
Cerra  FB.  Dellinger  RP,  Fein  AM,  Knaus  WA,  et  al.  Definition  for 
sepsis  and  organ  failure  and  guidelines  for  the  use  of  innovative  ther- 
apies in  sepsis.  Chest  1992;101(6):1644-1655. 

95.  Rangel-Frausto  MS,  Pittet  D.  Costigan  M.  Hwang  T,  Davis  CS,  Wen- 
zel  RP.  The  natural  history  of  the  systemic  inflammatory  response 
syndrome  (SIRS).  A  prospective  study.  JAMA  1995;273(2):1 17-123. 

96.  Doebbeling  BN,  Stanley  GL,  Sheetz  CT.  Pfaller  MA.  Houston  AK, 
Annis  L,  Li  N,  Wenzel  RP.  Comparative  efficacy  of  alternative  hand- 
washing agents  in  reducing  nosocomial  infections  in  intensive  care 
units.  N  Engl  J  Med  1992;327(2):88-93. 

97.  Maki  DG.  Control  of  colonization  and  transmission  of  pathogenic 
bacteria  in  the  hospital.  Ann  Intern  Med  1978:89(5,  Part  21:777-780. 

98.  Klein  BS,  Perloff  WH,  Maki  DG.  Reduction  of  nosocomial  infec- 
tion during  pediatric  intensive  care  by  protective  isolation.  N  Engl 
J  Med  1989;320(26):1714-1721. 

99.  Bassin  AS.  Niederman  MS.  Prevention  of  ventilator-associated  pneu- 
monia. An  attainable  goal?  Clin  Chest  Med  1995;16(  1 ):  195-208. 

100.  Tryba  M.  Sucralfate  versus  antacids  of  H2-antagonists  for  stress  ulcer 
prophylaxis:  a  meta-analysis  on  efficacy  and  pneumonia  rate.  Crit 
Care  Med  1991;19:942-949. 

101.  Cook  DJ.  Laine  LA.  Guyatt  GH.  Raffin  TA.  Nosocomial  pneumonia 
and  the  role  of  gastric  pH.  A  meta-analysis.  Chest  1991  ;100(  1 1:7-13. 

102.  Cook  DJ,  Reeve  BK,  Scholes  LC.  Histamine-2-receptor  antagonists 
and  antacids  in  the  critically  ill  population:  stress  ulceration  versus 
nosocomial  pneumonia.  Infect  Control  Hosp  Epidemiol  1994:15: 
437-442. 

103.  Mahul  P.  Auboyer  C,  Jospe  R.  Ros  A.  Guerin  C.  el  Khouri  Z,  et  al. 
Prevention  of  nosocomial  pneumonia  in  intubated  patients:  respective 
role  of  mechanical  subglottic  secretions  drainage  and  stress  ulcer  pro- 
phylaxis. Intensive  Care  Med  1992;  18(  I  ):20-25. 

1 04.  Valles  J,  Artigas  A,  Rello  J,  Bonsoms  N,  Fontanals  D,  Blanch  L,  et 
al.  Continuous  aspiration  of  subglottic  secretions  in  preventing  ven- 
tilator-associated pneumonia.  Ann  Intern  Med  1995:122(3):  179-186. 

105.  Kollef  MH.  antibiotic  use  and  antibiotic  resistance  in  the  intensive 
care  unit:  Are  we  curing  or  creating  disease?  Heart  Lung  1994;23: 
363-367. 

106.  Craven  DE,  Goularte  TA,  Make  BJ.  Contaminated  condensate  in  me- 
chanical ventilator  circuits.  A  risk  factor  for  nosocomial  pneumo- 
nia? Am  Rev  Respir  Dis  1984:129(41:625-628. 

1 07.  Kollef  MH,  Shapiro  SD,  Fraser  VJ,  Silver  P,  Murphy  DM,  Trovil- 
lion  E.  et  al.  Mechanical  ventilation  with  or  without  7-day  circuit 
changes:  a  randomized  controlled  trial.  Ann  Intern  Med  1995;123 
(21:168-174. 

108.  Dreyfuss  D.  Djedaim  K.  Weber  P.  Brun  P.  Lanore  JJ.  Rahamani  J, 
et  al.  Prospective  study  of  nosocomial  pneumonia  and  of  patient  and 
circuit  colonization  during  mechanical  ventilation  with  circuit  changes 
every  48  hours  versus  no  change.  Am  Rev  Respir  Dis  1991:143(4, 
Part  11:738-743. 


RESPIRATORY  CARE  •  NOVEMBER  '95  VOL  40  NO  1  1 


139 


Ventilator- Associated  Pneumonia 


Hess  D.  Burns  E.  Romagnoli  D.  Kacmarek  RM.  Weekly  ventilator 
eireuit  changes.  A  strategy  to  reduce  costs  without  affecting  pneu- 
monia rates.  Anesthesiology  [995;82(4):903-91  1. 
Dreyfuss  D,  Djedaini  K.  Gros  I.  Mier  L,  Le-Bourdelles  G.  Cohen  Y, 
et  al.  Mechanical  ventilation  with  heated  humidifiers  or  heat  and 
moisture  exchangers:  effects  on  patient  colonization  and  incidence 
Oi  nosocomial  pneumonia.  AmJ  Respir  Crit  Care  Med  1995;  151(4): 
986-992. 

Tablan  OC.  Anderson  U,  Arden  NH,  Breiman  RF,  Butler  1C.  Mc- 
Neil MM.  Hospital  Infection  Control  Practices  Advisory  Commit- 
tee. Guideline  for  prevention  of  nosocomial  pneumonia.  Respir  Care 
1994:391 12):  1191-1236. 

The  Intravenous  Immunoglobulin  Collaborative  Study  Group.  Pro- 
phylactic intravenous  administration  of  standard  immune  globulin 
as  compared  with  core-lipopolysaccharide  immune  globulin  in  pa- 
tients at  high  risk  of  postsurgical  infection.  N  Engl  1  Med  1992:327 
(41:234-240. 

Sahn  SA.  Continuous  lateral  rotational  therapy  and  nosocomial  pneu- 
monia. Chest  199 1;99(5):  1263-1267. 

Fink  MP.  Helsmoortel  CM.  Stein  KL.  Lee  PC.  Cohn  SM.  The  ef- 
ficacy of  an  oscillating  bed  in  the  prevention  of  lower  respiratory  tract 
infection  in  critically  ill  victims  of  blunt  trauma.  A  prospective  study. 
Chest  1990:97(11:132-137. 
deBoisblanc  BP,  Castro  M,  Everret  B,  Grender  J,  Walker  CD.  Sum- 


mer WR.  Effect  of  air-supported,  continuous,  postural  oscillation  on 
the  risk  of  early  ICU  pneumonia  in  nontraumatic  critical  illness.  Chest 
1993;103(5):  1543-1547. 

Bergogne-Berezin  E.  Treatment  and  prevention  of  nosocomial  pneu- 
monia. Chest  1995;108:26S-34S. 

Gisselbrecht  C,  Prentice  HG,  Bacigalupo  A,  Biron  P,  Milpied  N. 
Rubie  H.  et  al.  Placebo-controlled  phase  III  trial  of  lenograstim  in 
bone-marrow  transplantation.  Lancet  1994;343(8899):696-700. 
Maher  DW.  Lieschke  GJ,  Green  M,  Bishop  J.  Stuart-Harris  R.  Wolf  M. 
et  al.  Filgrastim  in  patients  with  chemotherapy-induced  febrile  neu- 
tropenia. A  double-blind,  placebo-controlled  trial.  Ann  Intem  Med 
1994;121(7):492-501. 

Pizzo  PA.  Current  issues  in  the  antibiotic  primary  management  of 
the  febrile  neutropenic  cancer  patient:  a  perspective  from  the  National 
Cancer  Institute.  J  Hosp  Infect  1990;15(Suppl  A):41-48. 
Dever  LL,  Johanson  WG.  Jr.  Nosocomial  pneumonia.  In:  Sim- 
mons DH,  Tiemey  DF,  editors.  Current  pulmonology,  vol.  13.  St. 
Louis:  Mosby,  1993:1-28. 

Moore  RD.  Smith  CR.  Lietman  PS.  Association  of  aminoglycoside 
plasma  levels  with  therapeutic  outcome  in  gram-negative  pneumonia. 
Am  J  Med  1984;77(4):657-662. 

Kim  JH.  Gallis  HA.  Observations  on  spiraling  empiricism:  its  caus- 
es, allure,  and  perils,  with  particular  reference  to  antibiotic  therapy. 
Am  J  Med  1989:87(2):201-206. 


Don't  miss  the 

Research  Symposium 

at  the  1995 

Annual  Convention 

of  the  American  Association 

for  Respiratory  Care 

Orlando,  Florida  •  Dec.  2-5,  1995 


1140 


RESPIRATORY  CARE  •  NOVEMBER  '95  VOL  40  NO  I  1 


Case  Reports 


Median  Nerve  Damage  from  Brachial  Artery  Puncture: 
A  Case  Report 

Mary  E  Watson  EdD  RRT 


This  report  describes  a  ease  in  which  puncture  of  the  brachial  artery  to  ob- 
tain a  sample  for  blood-gas  analysis  resulted  in  damage  to  the  median  nerve 
with  a  persisting  neuropathy  and  apparent  loss  of  function.  Errors  in  judg- 
ment and  contributions  to  possible  negligence  included  ( 1 )  inappropriate  choice 
of  sampling  site;  (2)  lack  of  knowledge  of  precautions  and  possible  compli- 
cations; (3)  incomplete/inadequate  description  of  optimal  procedure  in  de- 
partmental procedure  manual;  (4)  arbitrary  selection  of  the  dominant  hand. 
[Respir  Care  1995;40(  1 1 ):  1 141-1 143] 


Introduction 

Although  sampling  arterial  blood  is  a  commonly  practiced 
procedure,  it  is  not  without  possible  complications.  Choos- 
ing the  artery  for  puncture  is  important  for  patient  safety  and 
requires  knowledge  of  the  anatomy  of  the  nerves  and  ves- 
sels of  the  arm  and  hand  as  well  as  the  possible  complica- 
tions related  to  each  site.  The  choice  of  site  is  based  on  ac- 
cessibility, collateral  circulation,  and  safety.  A  description 
of  criteria  for  selection  and  the  complications  related  to  each 
site  is  not  the  intent  of  this  report  but  can  be  found  elsewhere 
for  review.1 4 

The  literature  suggests  that  the  vessel  of  choice  for  ar- 
terial punctures  in  adults  is  the  radial  artery .2-4"i: The  AARC 
Clinical  Practice  Guidelines  for  sampling  arterial  blood  are 
not  explicit  but  do  imply  that  the  radial  artery  is  the  first  con- 
sideration by  stating  it  first  in  the  list  of  possible  sites.1  The 
approved  national  standard  of  the  National  Committee  for 
Clinical  Laboratory  Standards  (NCCLS)  states  that  in  cur- 
rent practice  the  most  commonly  used  site  for  arterial  punc- 
ture is  the  radial  artery.1 

The  brachial  artery  is  considered  an  alternative  when  radial 


Dr  Watson  is  Chair,  Cardiopulmonary  Sciences  Department.  North- 
eastern University.  Boston.  Massachusetts. 

Reprints:  Mary  Watson  EdD  RRT.  Cardiopulmonary  Sciences  Department. 
Northeastern  University.  100DK,  360  Huntington  Ave,  Boston  MA  021 15. 


arteries  are  unavailable.  However  this  site  is  not  without 
risks.2-4'5'8'9-B14One  reference  goes  so  far  as  to  state  that  punc- 
tures by  nonphysicians  should  be  limited  to  the  radial  arteries.4 

The  purpose  of  this  article  is  to  report  a  case  of  median  nerve 
damage — a  risk  of  brachial  artery  puncture.  This  case  further 
justifies  why  the  radial  arteries  are  ruled  out  first  before  con- 
sidering another  site  for  puncture.  A  second  focus  is  to  pre- 
sent some  considerations  for  practitioners  regarding  the  legal 
risks  of  being  unable  to  defend  procedures  performed  on  pa- 
tients, the  importance  of  keeping  abreast  of  the  literature,  and 
the  importance  of  assuring  continuing  competence. 

The  risk  of  median  nerve  damage  from  brachial  artery 
puncture  appears  to  be  an  understated  problem.  It  is  not  on 
the  list  of  hazards/complications  in  the  AARC  Clinical  Prac- 
tice Guidelines  nor  as  a  hazard  of  arterial  puncture  in  the 
NCCLS  standards.11  One  author  has  stated  that  thousands 
of  brachial  artery  punctures  have  been  performed  in  his  de- 
partment with  no  known  complications.15  However,  sever- 
al papers  report  median  nerve  neuropathy-'' ■8A14  and  neuropathy 
to  the  hand13  as  a  result  of  brachial  artery  punctures.  Com- 
plications have  been  reported  both  with  patients  being  treat- 
ed and  those  not  being  treated  with  anticoagulant  thera- 
py 5.8.9.13.14  in  two  rep0rted  cases  of  patients  not  being  treat- 
ed with  anticoagulants,  complications  ended  in  permanent 
disability,5  J1and  legal  action  was  taken  in  at  least  one  case.5 
I  present  another  case  of  a  patient  not  receiving  anticoagu- 
lants in  whom  brachial  artery  puncture  resulted  in  apparently 
permanent  median  nerve  damage.  Legal  action  resulted  in 
an  out-of-court  settlement  favoring  the  patient. 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1141 


Nerve  Damage  from  Arterial  Puncture 


Case  History 

A  40-year-old.  right-handed  man  entered  the  emergency 
room  at  a  community  hospital  with  complaints  of  flu-like 
symptoms  including  general  weakness,  fever,  nausea,  head- 
ache, and  diarrhea  for  5  days.  He  was  admitted  for  further 
study.  On  the  day  of  admission,  arterial  blood  was  sampled 
from  the  right  brachial  artery  by  a  medical  laboratory  tech- 
nologist. As  the  arterial  puncture  was  attempted,  involuntary 
movements  of  the  patient's  fingers  occurred,  and  he  com- 
plained of  pain  in  the  elbow  area.  The  pain  occurred  along 
the  ulnar  aspect  of  the  right  arm  and  radiated  down  the  fore- 
arm into  the  hand.  The  patient  had  difficulty  straightening 
his  hand  and  moving  his  fingers  and  could  not  hold  a  pen. 
He  developed  swelling  in  his  arm  and  subsequently  noticed 
numbness  and  weakness.  The  patient  continued  to  complain 
of  pain,  weakness,  and  numbness  in  his  arm  and  hand.  A  neu- 
rology consultant  recommended  ice  packs  and  a  sling,  with 
some  relief  of  symptoms. 

Several  days  later,  the  patient  continued  to  complain  of 
pain  and  was  evaluated  by  a  physical  therapist.  He  was  found 
to  have  loss  of  function  manifested  by  the  inability  to  write 
or  feed  himself  with  that  hand.  He  continued  to  have  pain 
in  the  right  arm  from  the  shoulder  to  the  fingers.  An  exer- 
cise program  was  prescribed,  and  he  was  encouraged  to  use 
his  right  arm  and  hand  as  much  as  possible.  He  was  discharged 
the  next  day  with  therapy  being  continued  on  an  outpatient 
basis.  His  discharge  diagnosis  included  acute  viral  illness  and 
ulnar  neuritis. 

Subsequent  evaluation  by  electromyography  produced  find- 
ings consistent  with  a  median  neuropathy  occurring  at  or  prox- 
imal to  the  elbow,  with  signs  of  chronic  neuropathy.  The  pa- 
tient was  diagnosed  with  traumatic  neuropathy  of  the  prox- 
imal right  median  nerve.  He  suffers  permanent  partial  disability 
with  25%  permanent  impairment  due  to  combined  loss  of 
motor  power  and  sensation  and  pain  in  the  right  upper  arm. 

The  patient  never  regained  full  permanent  function  of  the 
right  arm  and  hand.  Prior  to  the  injury,  he  had  enjoyed  work- 
ing out  in  a  health  club  3  to  4  hours  per  week  and  participating 
in  physical  activities  such  as  tennis  and  running.  Motion  of 
the  arm  and  shoulder  still  causes  pain.  The  patient  subsequently 
brought  a  malpractice  action  against  the  hospital  for  negli- 
gence in  sampling  arterial  blood  and  for  wrongful  conduct 
resulting  in  a  permanent  loss  of  function. 

Discussion 

The  basis  for  the  out-of-court  settlement  was  the  reason- 
able assurance  that  the  patient  would  not  have  been  injured 
had  the  medical  technologist  not  committed  several  errors  in 
judgment,  consuued  as  possible  negligence.  These  errors  should 
be  understood  by  Students  learning  blood  gas  procedures  and 
should  serve  as  reminders  to  practitioners  and  department  pol- 
icy writers  who  are  considering  the  protocol  to  be  incorpo- 


rated into  policies  and  procedures  for  sampling  arterial  blood. 

Error  1 :  The  brachial  artery  was  the  site  chosen  for  sam- 
pling the  blood,  but  there  was  no  apparent  clinical  reason  for 
avoiding  the  radial  artery.  The  technologist  could  not  justi- 
fy her  choice  of  the  brachial  artery  as  the  site  of  puncture  for 
this  patient.  This  issue  addresses  the  importance  of  practitioners 
being  able  to  defend  the  care  they  are  giving  to  patients. 

The  need  to  use  the  brachial  artery  for  puncture  is  present 
in  only  3-5%  of  those  requiring  blood  gas  analysis  and  is  usu- 
ally due  to  inadequate  collateral  circulation  through  the  ulnar 
artery.2  Although  radial  nerve  damage  can  occur  from  a  ra- 
dial puncture,  the  fact  that  the  median  nerve  is  closely  par- 
allel to  the  course  of  the  brachial  artery  is  a  major  reason  for 
not  choosing  the  brachial  artery  for  puncture  (Fig.  1 ).  Trau- 
ma to  the  median  nerve  may  occur  while  brachial  artery  punc- 
ture is  being  attempted,  with  subsequent  permanent  nerve  dam- 
age, as  occurred  in  this  case  and  other  reported  cases.513 


Radial 
Artery 


Fig.  1 .  Sketch  showing  how  the  large  median  nerve  parallels  the 
brachial  artery.  (Adapted  from  Reference  2,  with  permission.) 


Error  2:  The  technologist  appeared  to  have  little  knowl- 
edge of  the  criteria  for  choosing  a  site  for  arterial  puncture 
or  of  the  possible  complications  and  contraindications  to  sam- 
pling arterial  blood  from  various  sites.  Maintaining  skills  is 
the  responsibility  of  both  the  practitioner  and  the  health-care 
facility.  NCCLS  standards  state  that  every  person  perform- 
ing arterial  punctures  should  be  familiar  with  the  dangers  of 
the  procedures  and  with  precautions  designed  to  prevent  haz- 
ards.3 The  AARC  Clinical  Practice  Guideline  for  sampling 
arterial  blood  also  emphasizes  the  need  for  periodic  re-eval- 
uation of  practitioners  on  this  procedure,  to  assure  continu- 
ing competence  of  skill  and  knowledge.'  In  addition,  the  Joint 
Commission  on  Accreditation  of  Health  Care  Organizations 
requires  ongoing  training  to  maintain  the  knowledge  and  skill 
of  all  personnel."1 


1142 


Respiratory  Care  •  November  '95  Voi.4()No  1 


Nervk  Damage  from  Arterial  Puncture 


The  practitioner  was  also  not  aware  that  the  Department 
procedure  manual  included  a  procedure  for  sampling  arterial 
blood  that  stated  that  the  radial  artery  is  the  preferred  site.  This 
error  addresses  the  need  for  practitioners  to  be  responsible 
for  knowing  and  following  what  is  in  the  procedure  manu- 
al. In  addition,  the  Department  has  the  responsibility  to  as- 
sure that  the  manual  is  actually  used  by  practitioners  and  not 
just  by  policy  writers. 

Error  3:  Sampling  arterial  blood  in  the  hospital  in  ques- 
tion is  a  shared  responsibility  between  the  laboratory  and 
the  Respiratory  Therapy  Department.  Neither  department 
included  the  Allen's  Test  or  modified  Allen's  Test  as  part 
of  the  procedure  to  check  for  collateral  circulation.  The  lit- 
erature indicates  that  this  should  be  part  of  the  proce- 
dure.I4-6-7"  The  Allen's  Test  is  a  practical  method  of  assessing 
collateral  circulation  at  the  bedside.  This  error  addresses  the 
need  for  departments  to  be  sure  that  procedures  are  updat- 
ed based  on  current  standards  of  practice. 

Error  4:  The  blood  sample  was  obtained  from  the  domi- 
nant arm.  Puncturing  an  artery  in  the  nondominant  arm  or 
wrist  is  logical  and  makes  good  clinical  sense.  When  puls- 
es are  equal,  the  artery  on  the  nondominant  side  should  be 
chosen  for  puncture."  This  criterion  is  not  commonly  included 
in  the  written  procedures  but  is  an  important  consideration. 
If  an  injury  occurs  in  the  nondominant  limb,  the  patient  is 
less  incapacitated.  For  example,  a  right-handed  patient  with 
left-handed  problems  would  most  likely  be  able  to  carry  out 
daily  activities.  In  this  case  the  patient  was  right-handed,  and 
there  was  no  evidence  to  disallow  use  of  the  arteries  in  the 
left  arm. 

The  technologist  had  many  years  of  experience  in  sam- 
pling arterial  blood,  yet  did  not  know  many  important  facts 
related  to  the  procedure.  There  was  no  attempt  on  her  part  to 
stay  updated  on  this  protocol.  The  hospital  was  possibly  neg- 
ligent both  for  not  having  a  procedure  that  meets  the  standard 
of  practice  and  for  not  assuring  adequate  training  in  the  pro- 
cedure for  the  technicians.  Although  there  was  a  department 
policy  in  place  for  assuring  continued  competence,  it  was  in- 
adequate in  this  situation. 

Although  the  case  presented  here  did  not  involve  a  res- 
piratory therapist,  those  of  us  who  provide  respiratory  care 
can  learn  from  the  experience.  The  potential  for  nerve  dam- 
age with  brachial  artery  puncture  is  a  real  risk  to  patients  and 
a  legal  risk  for  practitioners.  Brachial  artery  punctures  should 
not  be  performed  unless  the  radial  arteries  have  been  ruled 
out  for  use.  When  the  brachial  artery  must  be  punctured,  the 
less  dominant  arm  should  be  used  in  case  injury  does  occur. 

When  we  consider  the  expanding  role  of  respiratory  ther- 
apists, the  importance  of  providing  documentation  to  assure 
professional  training  can  not  be  overstated.  When  roles  and 
responsibilities  become  more  diverse,  assuring  that  skills  are 


up  to  date  becomes  more  complex.  Practitioners  have  the  re- 
sponsibility to  know  the  procedure  manual  and  to  keep  them- 
selves current  with  respect  to  the  literature.  Practitioners  may 
find  themselves  in  a  situation  where  they  have  to  defend  their 
performance. 

When  a  department  writes  new  policies  and  procedures 
or  updates  old  policies,  it  is  critical  that  steps  be  formalized 
to  ensure  that  all  appropriate  staff  members  are  aware  of  these 
procedural  changes.  Additionally,  the  need  for  recertification 
to  assure  continued  competence  is  necessary. 

REFERENCES 

1 .  American  Association  for  Respiratory  Care.  Clinical  practice  guide- 
lines: Sampling  for  arterial  blood  gas  analysis.  Respir  Care  1992:37 
(8):913-917. 

2.  Malley  W.  Clinical  blood  gases — applications  and  noninvasive  al- 
ternatives. Philadelphia:  WB  Saunders,  1990:6-18. 

3.  National  Committee  for  Clinical  Laboratory  Standards.  Percutaneous 
collection  of  arterial  blood  for  laboratory  analysis.  2nd  ed.  Approved 
standard.  Villanova  PA:  National  Committee  for  Clinical  Labora- 
tory Standards.  1992:1-32. 

4.  Shapiro  BA,  Peruzzi  WT,  Templin  R.  Clinical  application  of  blood 
gases.  5th  ed.  Chicago:  Year  Book  Medical  Publishers  Inc.  1994: 
301-306. 

5.  Berger  A.  Brachial  artery  puncture:  the  need  for  caution.  J  Fam  Pract 
1989;28(6):720-721. 

6.  Blodgett  D.  Manual  of  respiratory  care  procedures.  Philadelphia:  JB 
Lippincott  Co.  1987:194-195. 

7.  Lane  EE,  Walker  JF,  Clinical  arterial  blood  gas  analysis.  St.  Louis, 
CV  Mosby  Company,  1987:202-209. 

8.  Luce  EL,  Futrell  JW.  Wilgis  EF,  Hoopes  JE.  Compression  neuropathy 
following  brachial  arterial  puncture  in  anticoagulated  patients.  J  Trau- 
ma. 1976:16(91:717-721. 

9.  Macon  WL  4th.  Futrell  JW.  Median-nerve  neuropathy  after  percu- 
taneous puncture  of  the  brachial  artery  in  patients  receiving  anti- 
coagulants. N  Engl  J  Med  1973:288(261:1396. 

10.  Peters  JA.  Hodgkin  JE.  Collier  CR.  Blood  gas  analysis  and  acid-base 
physiology.  In:  Burton  GG.  Hodgkin  JE,  Ward  JJ.  editors.  Respiratory 
care — a  guide  to  clinical  practice.  Philadelphia:  JB  Lippincott  Co. 
1991:181-183. 

1 1.  Plunkett  PF.  Blood  gas  interpretation.  In:  Barnes  TA.  editor.  Res- 
piratory care  practice.  Chicago:  Year  Book  Medical  Publishers  Inc, 
1994:617-618. 

12.  Schwartz  MI.  Levin.  DC.  Understanding  blood  gases.  New  York: 
Sanofi  Winthrop  Pharmaceutics.  1978:4. 

13.  McCready  RA,  Hyde  GL,  Bivins  BA,  Hagihara  PF.  Brachial  ar- 
terial puncture:  a  definite  risk  to  the  hand.  South  Med  J  1984:77: 
786-789. 

14.  Neviaser  RJ.  Adams  JP.  May  GI.  Complications  of  arterial  puncture 
in  anticoagulated  patients.  J  Bone  Joint  Surg,  1 976:  58(  2 1:2 1 8-220. 

15.  Beauchamp  RK.  Pulmonary  function  testing  procedures.  In:  Barnes  TA. 
editor.  Respiratory  care  practice.  Chicago:  Year  Book  Medical  Pub- 
lishers Inc.  1994:81. 

1 6.  Joint  Commission  of  Accreditation  of  Healthcare  Organizations.  Ori- 
entation, training,  and  education  of  staff.  In:  Accreditation  manual 
for  hospitals,  joint  commission  of  accreditation  of  healthcare  or- 
ganizations. Oakbrook  Terrace  IL:  Joint  Commission  of  Accreditation 
of  Healthcare  Organizations,  1993. 


RESPIRATORY  CARE  •  NOVEMBER  '95  VOL  40  NO 


1143 


A  Case  of  Patient-Ventilator  Dyssynchrony  Caused  by  Inadvertent  PEEP 

Tom  Blackson  RRT,  Joseph  Ciarlo  BA  RRT,  and  Albert  Rizzo  MD 


Despite  years  of  experience  and  a  plethora  ofliterature  regarding  manage- 
ment strategies  for  mechanically  ventilated  patients  with  chronic  airflow  ob- 
struction (CAO),  the  resources  of  health-care  providers  in  the  acute  care  set- 
ting continue  to  be  challenged.  We  report  a  case  demonstrating  the  successful 
application  of  the  use  of  extrinsic  positive  end-expiratory  pressure  (PEEPe), 
to  offset  inadvertent  PEEP  (PEEPA)  in  a  patient  with  CAO.  The  use  of  con- 
ventional ventilatory  strategies  in  this  patient  resulted  in  patient-ventilator 
dyssynchrony,  and  repeated  attempts  at  weaning  were  unsuccessful.  We  em- 
ployed esophageal  pressure  manometry  to  guide  titration  of  PEEPe  up  to  15 
cm  HiO,  which  allowed  us  to  stabilize  and  eventually  wean  this  patient  from 
mechanical  ventilatory  support.  This  case  demonstrates  that  the  nonconventional 
use  of  PEEPe  with  appropriate  monitoring  can  be  beneficial  in  patients  with 
CAO  and  PEEPA.  [Respir  Care  1995;40  ( 1 1 ):  1 144-1 147] 


Introduction 

Inadvertent  positive  end-expiratory  pressure  (PEEPa)  is 
common  in  mechanically  ventilated  patients  with  chronic  air- 
flow obstruction  (CAO).1  It  has  been  suggested  that  the  ap- 
plication of  PEEPe  to  patients  who  develop  PEEPa  during 
mechanical  ventilation  may  decrease  patient  work  of  breath- 
ing ( WOBp).2-3  Despite  these  findings,  the  use  of  PEEPE  to 
decrease  WOBp  in  patients  with  CAO  and  PEEPa  during  me- 
chanical ventilation  remains  controversial.4  We  present  a  case 
to  illustrate  the  beneficial  effects  of  PEEPE  on  both  WOBP 
and  patient-ventilator  dyssynchrony  during  mechanical  ven- 
tilation of  a  patient  with  CAO  and  PEEPa- 

Case  Summary 

The  patient,  a  60-year-old.  238-pound,  (ideal  body  weight 
154  pounds)  Caucasian  woman  with  advanced  chronic  ob- 


Mr  Blackson  is  Director  of  Clinical  Education  and  Mr  Ciarlo  is 
Instructor,  School  oi  Respiratory  Cure.  Medical  Center  of  Delaware  and 
Delaware  Technical  and  Community  College.  Dr  Rizzo  is  Instructor — 
Jefferson  Medical  College  and  Medical  Center  of  Delaware,  Wilming- 
ton, Delaware. 

The  authors  have  no  relationships,  financial  01  otherwise,  with  the  manu- 
facturers of  commercial  products  mentioned  in  this  paper 

Reprints:  Tom  Blackson  RRT.  Medical  Center  ol  Delaware,  School  of 
Respirator)  Care,  .sol  Wesi  14th  Street,  Wilmington  DE  19899 


structive  pulmonary  disease  (COPD),  bullous  emphysema, 
and  many  previous  hospital  admissions,  presented  with  acute 
respiratory  distress.  She  was  having  an  acute  exacerbation  of 
COPD.  most  likely  due  to  infectious  bronchitis,  and  required 
intubation  and  mechanical  ventilation.  She  was  admitted  to 
the  medical  intensive  care  unit  for  treatment  and  monitoring. 
Her  medical  history  revealed  recurrent  exacerbations  of  COPD, 
chronic  hypercarbia,  and  frequent  urinary  tract  infections.  She 
was  a  60-pack-year  cigarette  smoker.  During  this  admission 
she  was  managed  with  oral  endotracheal  intubation  and  var- 
ious mechanical  ventilation  modalities  including  assist  con- 
trol, intermittent  mandatory  ventilation,  and  pressure  support. 
Her  acute  exacerbation  was  treated  with  aerosolized  fi  ago- 
nists, inhaled  ipratropium  bromide,  systemic  corticosteroids, 
theophylline  preparations,  and  antibiotics.  Because  of  pro- 
longed ventilatory  requirements,  a  tracheostomy  was  placed. 
Initially,  a  #6  trach  tube  (inner  diameter  7.0  mm  and  length 
78  mm)  was  used  (Shiley  Inc.  Irvine  CA). 

Patient  Assessment 

The  patient  remained  ventilator  dependent  during  the  next 
several  weeks,  and  various  reasons  for  failure  to  wean  were 
considered,  including  the  airway  resistance  of  the  tracheostomy 
tube.  At  this  time  she  was  awake,  alert  and  cooperative.  She 
showed  no  evidence  of  infection  as  evidenced  by  a  normal 
white  blood  cell  count  and  body  temperature.  Her  chest  ra- 
diograph was  unremarkable  except  for  chronic  hyperinflation. 
Ventilator  settings  (Puritan-Bennett  7200.  Carlsbad  CA)  were 


1144 


Rl  SI'IRATORY  CARK  •  NOVEMBER  H).S  Vol.  40  Nt)  I  I 


Dyssynchrony  &  Inadvertent  PEEP 


Fdo:  0.35,  tidal  volume  (Vt)  650  mL,  assist-control  mode, 
back-up  rate  14  breaths/min,  and  PEEPe  5  cm  H^O.  This  pa- 
tient made  12-18  inspiratory  efforts/mil)  that  did  not  trigger 
a  positive-pressure  breath.  Routine  care  was  provided  including 
tracheal  suctioning,  administration  of  aerosolized  bron- 
chodilators,  and  comfortable  patient  positioning.  The  patient's 
airway  was  changed  from  a  #6  to  a  #8  tracheostomy  tube  (Shi- 
ley  Inc,  Irvine  CA)  with  an  inner  diameter  of  8.5  mm  and  84 
mm  in  length  to  minimize  the  work  of  breathing  imposed  by 
her  airway.  However,  patient-ventilator  dyssynchrony  was 
not  relieved  by  these  attempts  nor  by  our  efforts  to  optimize 
ventilator  sensitivity  and  inspiratory  flow  settings. 

Evaluation  and  Treatment 

We  evaluated  this  patient  using  esophageal  and  proximal- 
airway  pressure  manometry  (CP-100,  Bicore,  Irvine  CA)  to 
elucidate  the  cause  of  the  dyssynchrony.  A  #16  French  Smart- 
Cath  (a  combination  feeding  tube  and  esophageal  pressure  [Pes] 
catheter  [Bicore,  Irvine  CA])  was  placed  to  monitor  Pes,  as 
a  surrogate  of  intrathoracic  pressure.  The  position  of  the 
esophageal  catheter  was  verified  using  Baydur  et  al's  method.5 
The  flow  transducer  ( VarFlex,  Bicore,  Irvine  CA)  was  placed 
between  the  ventilator  circuit  and  the  patient's  airway  to  mon- 
itor airway  pressure  (Paw)  and  inspired  and  expired  tidal  vol- 
umes and  flows  (V-n,  Vte,  and  Vi,  Vg).  Evaluation  of  the  graph- 
ic display  on  the  monitor's  patient- ventilator  synchrony  screen 
confirmed  our  observations  (Fig.  1  A).  We  adjusted  the  ven- 
tilator to  the  pressure  support  mode  (PSV)  with  an  inspira- 
tory pressure  of  15  cm  HiO  and  5  cm  H2O  PEEPe.  Although 
the  dyssynchrony  improved,  it  was  not  eliminated  (Fig.  IB). 
Baseline  values  of  WOBp  were  not  merely  elevated  but  were 
in  a  range  greater  than  five  times  normal  WOBp."  The  change 
in  Pes  (APes)  necessary  to  trigger  the  ventilator,  PEEPa  and 
P0.1  (a  reflection  of  the  patient's  neural  drive  to  breath)  were 
also  unacceptably  high  (Table  1). 

Table  1.  Results  Derived  from  Monitoring  40  Breaths  during  Pressure 
Support  Ventilation  at  15  cm  HiO  with  2  Levels  of  Extrinsic 
PEEP  (PEEPE).  Values  are  mean  (SD). 


Variable 

PEEPe 

PEEPE 

Percent 

5  cm  H20 

15cmH20 

Change 

WOBp'  (J/L) 

2.67  (0.39) 

1.52  (0.34) 

-431 

APes(cmH20) 

28.90  (7.33) 

15.70  (7.50) 

-46' 

PEEPa  (cm  H2Ol 

22.30  (6.80) 

14.00  (4.12) 

-37' 

PEEPT  (cm  H20) 

28.30  (6.80) 

29.90  (3.17) 

+6* 

P0.1  (cm  H20) 

7.46  (2.53) 

4.21   (2.22) 

-44' 

CL(L/cmH20) 

51.34(24.34) 

74.42(31.06) 

+45' 

Vti(L) 

0.36  (0.09) 

0.45  (0.06) 

+25' 

*  WOBp.  palienl  work  of  breathing;  PCs,  esophageal  pressure  change,  PEEPa.  inad- 
vertent positive  end-expiratory  pressure;  PEEP-]-,  end-expiratory  alveolar  pressure; 
Pq,I  inspiratory  pressure  at  100  ms  after  the  start  of  inspiratory  flow;  Cl.  lung  com- 
pliance; V-n,  inspired  tidal  volume. 
;  unpaired  nest,  p<  0.001.  *  unpaired  /test,  p  >  0.05. 


J r 


Fig.  1.  A.  Example  of  patient-ventilator  dyssynchrony  in  the  as- 
sist-control mode.  The  patient  is  making  inspiratory  efforts  evi- 
denced by  deflections  in  esophageal  pressure  (Pes)— a.  However, 
none  of  these  efforts  produce  a  drop  in  airway  pressure  (Paw)  suf- 
ficient to  trigger  the  ventilator — b.  B.  Example  of  patient  ventilator 
dyssynchrony  in  the  pressure-support  mode.  The  patient  is  mak- 
ing inspiratory  efforts  evidenced  by  deflections  in  Pes — a. 
However,  many  of  these  efforts  failed  to  produce  a  drop  in  airway 
pressure  (Paw)  sufficient  to  trigger  the  ventilator— b. 


Because  conventional  treatment  strategies  to  reduce  PEEPa 
were  ineffective,  we  titrated  PEEPe  levels  slowly  to  15  cm 
HiO  to  offset  PEEPa,  promote  patient-ventilator  synchrony, 
and  decrease  WOBp  and  APes.7  This  resulted  in  improved  pa- 
tient-ventilator synchrony  (Fig.  2B)  and  decreased  WOBp, 
APes,  PEEPA,  and  Pn.i  (Table  1 ).  We  compared  the  baseline 
values  for  these  variables  to  values  collected  after  the  increase 
in  PEEPe,  using  unpaired  t  tests  (more  conservative  than  paired 
t  tests).  The  differences  were  significant  (p  <  0.001 ).  Simi- 
lar improvements  in  patient-ventilator  synchrony  and  WOBp 
were  observed  at  night,  when  the  patient  was  ventilated  in  the 
assist-control  mode.  With  the  exception  of  the  increase  in 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1145 


Dyssynchrony  &  Inadvertent  PEEP 


PEEPe  from  5  cm  HiO  to  15  cm  H2O,  the  assist-control  ven- 
tilator settings  remained  unchanged  (Fig.  2A). 


Fig.  2.  A.  Example  of  improved  patient/ventilator  synchrony  in  (A) 
assist-control  mode  and  (B)  pressure  support  mode.  Note  that 
each  inspiratory  effort,  deflection  in  esophageal  pressure  (Pes) — a, 
is  associated  with  a  drop  in  airway  pressure  (Paw) — b  and  ventila- 
tor triggering. 


Discussion 

In  the  past,  the  assist-control  mode  of  ventilation  was  used 
as  an  initial  strategy  to  rest  or  unload  ventilatory  muscles  of 
patients  with  CAO  requiring  mechanical  ventilation  because 
of  ventilatory  failure.  More  recently,  pressure-support  strate- 
gies have  been  utilized  for  this  purpose."  The  benefits  of  these 
modes  are  based  on  the  assumption  that  each  inspiratory  ef- 
fort by  the  patient  triggers  the  ventilator,  allowing  it  to  pro- 
vide the  mechanical  work  for  inspiration.  Minimal  patient  ef- 
fort, as  reflected  by  AP0.  is  required  to  trigger  an  assisted  breath 
as  long  as  trigger  threshold  is  set  appropriately.  This  case 


demonstrates  that  these  assumptions  may  not  be  valid  in  pa- 
tients with  CAO  and  PEEPA  (Fig.  1  A).  As  a  result  of  the  high 
level  of  PEEPa  in  this  patient,  many  inspiratory  efforts  did 
not  produce  a  decrease  in  airway  pressure  sufficient  to  trig- 
ger the  ventilator  into  the  inspirator)'  phase.  This  occurred  de- 
spite the  fact  that  the  patient's  inspiratory  efforts  produced 
APCS  more  than  twice  normal.9 

As  has  been  reported  by  Marini.:7 '"  the  addition  of  PEEPe 
to  patients  with  CAO  on  mechanical  ventilation  may  make 
breath  triggering  easier  and  reduce  the  WOBp.  By  increas- 
ing PEEPe  in  such  patients,  it  may  be  possible  to  alter  the 
anatomic  position  of  the  equal  pressure  point,  resulting  in  a 
narrowing  of  the  gradient  between  end-expiratory  alveolar 
pressure  (PEEPt)  and  the  pressure  in  the  central  airways.710 
The  net  effect  of  this  change  should  be  a  reduction  in  patient 
effort  required  to  trigger  the  ventilator.  This  case  study  illustrates 
some  of  the  beneficial  effects  that  may  be  realized  when  PEEPe 
is  employed  to  offset  PEEPa — patient-ventilator  synchrony 
improved,  and  WOBp.  APes.  and  P0.1  decreased.  It  is  noteworthy 
that  these  beneficial  reductions  in  work  indices  were  ac- 
companied by  an  increase  in  V-n. 

Although  these  results  are  dramatic,  their  true  importance 
may  be  underappreciated  based  on  manometry  results  alone. 
With  the  esophageal  manometry  system  that  we  used.  APes 
that  is  not  followed  by  volume  displacement  is  not  counted 
as  a  breath  and  is  not  incorporated  into  WOBp  calculations. 
Therefore,  the  reductions  in  WOBp  and  APes,  as  calculated 
by  this  method,  may  not  fully  represent  the  reduction  in  oxy- 
gen cost  of  breathing  that  occurred.7 

Although  PEEPa  is  common  in  mechanically  ventilated 
patients,  not  all  patients  with  PEEPa  can  be  safely  and  ef- 
fectively managed  with  increased  levels  of  PEEPe-  If  PEEPa 
results  from  dynamic  airflow  obstruction,  increasing  levels 
of  PEEPe.  not  to  exceed  the  original  level  of  PEEPa.  should 
result  in  a  decrease  in  the  patient's  effort  to  breathe  without 
causing  further  lung  distention  or  placing  the  patient  at  in- 
creased risk  from  barotrauma  or  cardiovascular  depression. 
However,  if  PEEPa  is  caused  by  factors  other  than  dynam- 
ic airflow  obstruction,  the  addition  of  PEEPe  may  result  in 
increasing  PEEPt,1"  thereby  increasing  the  risk  of  barotrauma1 ' 
and  cardiovascular  depression.  For  these  reasons,  it  is  important 
to  differentiate  clinically  between  these  causes  of  PEEPa-  Once 
again,  this  case  illustrates  the  results  one  should  anticipate  if 
PEEPa  is  due  to  dynamic  airflow  obstruction.  While  being 
treated  with  a  PEEPe  of  5  cm  FhO.  our  patient's  average  PEEPt 
was  28.3  cm  H20  (SD  6.80).  Following  treatment  of  the  pa- 
tient with  a  PEEPe  equal  to  1 5  cm  rTO.  the  PEEPt  was  in- 
creased to  29.9  cm  H:0(SD  3.17).  This  change  was  not  sta- 
tistically significant  (unpaired  t  test,  p  >  0.05).  In  addition. 
the  VTi  increased  from  0.36  L  (SD  0.09)  with  the  patient  re- 
ceiving 5  cm  H;0  to  0.45  L  (SD  0.06)  once  the  patient  was 
treated  with  a  PEEPe  equal  to  15  cm  H2O.  The  increase  in 
Vti  occurred  while  the  patient  was  ventilated  with  a  constant 
pressure  support  level  of  15  cm  H^O.  The  patient's  arterial 


1146 


ki  siMR  \\n\<\  Caki  •  November  '95  Vol  40  No  1 1 


Dyssynchrony  &  Inadvertent  PEEP 


blood  pressure  remained  stable  at  150/80  mm  Hg  both  before 
and  after  titration  of  PEEPe.  There  was  no  radiologic  or  phys- 
ical evidence  of  barotrauma  at  any  time  during  this  patient's 
hospital  course.  These  results  implicate  flow  limitation  as  the 
cause  of  the  PEEPa  in  this  patient. 

For  comparison,  if  flow  limitation  had  not  been  the  cause 
of  the  PEEPa.  the  patient's  response  to  increasing  levels  of 
PEEPe  would  have  been  very  different.  The  PEEPj  would 
be  expected  to  increase  in  direct  proportion  to  the  elevat- 
ed PEEPe-10  While  employing  a  pressure-constant  strate- 
gy for  ventilation,  V-n  would  decrease  as  PEEPe  was  titrat- 
ed upward.  Results  of  this  nature  would  argue  against  the 
use  of  elevated  levels  of  PEEPe  which,  if  employed,  may 
place  the  patient  at  increased  risk  for  barotrauma  and  car- 
diovascular depression. 

Once  stabilized  with  15  cm  HiO  of  PEEPe.  our  patient  was 
transferred  to  an  intensive  respiratory  'weaning'  unit  where 
she  was  successfully  weaned  from  mechanical  ventilatory  sup- 
port. During  the  weaning  process,  PEEPe  was  maintained  at 
levels  sufficient  to  maintain  patient-ventilator  synchrony  pri- 
marily through  observation  of  her  triggering  efforts.  Esophageal 
and  proximal-airway  manometry  was  used  intermittently  as 
a  monitoring  tool  during  this  period.  Although  this  case  demon- 
strates that  benefits  may  be  realized  through  elucidation  and 
treatment  of  patient-ventilator  dyssynchrony  caused  by  PEEPa, 
many  questions  remain  to  be  answered.  What  is  the  role  of 
PEEPe  utilized  during  noninvasive  ventilatory  support  of  pa- 
tients with  CAO?  Should  the  level  of  PEEPe  employed  dur- 
ing bilevel,  noninvasive,  pressure  support  ventilation  be  ad- 
justed to  improve  patient- ventilator  synchrony  in  patients  with 
CAO?1213  Does  PEEPe  alone  have  a  role  in  the  prevention 
of  acute  respiratory  failure  due  to  ventilatory  muscle  fatigue 
in  patients  with  CAO?  How  soon  after  patient  stabilization 
should  attempts  be  made  to  reduce  PEEPe?  In  addition  to  ques- 
tions concerning  patient  management,  it  is  not  known  whether 
this  treatment  strategy  affects  the  length  of  hospital  stay  or 
days  of  mechanical  ventilation  required  when  compared  to 
conventional  PEEPe  treatment  in  this  category  of  patients. 
The  financial  impact  of  this  management  approach  is  also  un- 
known. Further  research  is  necessary  to  evaluate  the  long-range 
impact  of  this  treatment  strategy. 

Conclusions 

1.  PEEPA  during  mechanical  ventilation  of  patients  with 
CAO  may  cause  an  increase  in  the  WOBp  necessary  to 
trigger  a  positive  pressure  breath.  This  increase  in  work 
appears  to  be  independent  of  the  mode  of  ventilation  or 


trigger  threshold  employed.  The  elevated  WOBp  may  be 
reduced  with  appropriate  adjustment  of  PEEPe. 

2.  PEEPa  represents  one  of  the  causes  of  patient-ventila- 
tor dyssynchrony  during  positive  pressure  ventilation  of 
patients  with  CAO.  Dyssynchrony  caused  by  PEEPa  may 
be  reduced  with  proper  selection  of  PEEPe  level. 

3.  The  use  of  esophageal  manometry  may  be  useful  in  the 
elucidation  and  treatment  of  both  patient- ventilator  dyssyn- 
chrony and  increased  WOBp  induced  by  PEEPa. 


REFERENCES 


1.  Pepe  PE,  Marini  JJ.  Occult  positive  end-expiratory  pressure  in  me- 
chanically ventilated  patients  with  airflow  obstruction:  the  auto-PEEP 
effect.  Am  Rev  Respir  Dis  1 982;  1 26(  1 ):  1 66- 1 70. 

2.  Smith  TC,  Marini  JJ.  Impact  of  PEEP  on  lung  mechanics  and  work 
of  breathing  in  severe  airflow  obstruction.  J  Appl  Physiol  1988;65 
(4):  1488- 1499. 

3.  Petrof  BJ,  Legare  M,  Goldberg  P,  Milic-Emili  J.  Gottfried  SB.  Con- 
tinuous positive  airway  pressure  reduces  work  of  breathing  and  dys- 
pnea during  weaning  from  mechanical  ventilation  in  severe  chron- 
ic obstructive  pulmonary  disease.  Am  Rev  Respir  Dis  1990;  141 
(2):281-289. 

4.  Tuxen  DV.  Detrimental  effects  of  positive  end-expiratory  pressure 
during  controlled  mechanical  ventilation  of  patients  with  severe  air- 
flow obstruction.  Am  Rev  Respir  Dis  1989;  140( l):5-9. 

5.  Baydur  A,  Behrakis  PK,  Zin  WA,  Jaeger  M,  Milic-Emili  J.  A  sim- 
ple method  for  assessing  the  validity  of  the  esophageal  balloon  tech- 
nique. Am  Rev  Respir  Dis  1982;126(5);788-791. 

6.  Banner  MJ.  Jaeger  MJ.  Kirby  RR.  Components  of  the  work  of  breath- 
ing and  implications  for  monitoring  ventilator-dependent  patients. 
Crit  Care  Med  1994;22(3):515-523. 

7.  Marini  JJ.  Lung  mechanics  determinations  at  the  bedside:  instru- 
mentation and  clinical  application.  Respir  Care  1990;35(7):669-696. 

8.  Maclntyre  N.  Pressure  support  ventilation:  effects  on  ventilatory  re- 
flexes and  ventilatory-muscle  workloads.  Respir  Care  1987;32(6): 
447-457. 

9.  Petros  AJ,  Lamond  CT,  Bennett  D.  The  Bicore  pulmonary  monitor: 
a  device  to  assess  the  work  of  breathing  while  weaning  from  me- 
chanical ventilation.  Anaesthesia  1993;48(1 1):985-988. 
Marini  JJ.  Should  PEEP  be  used  in  airflow  obstruction?  (editorial). 
Am  Rev  Respir  Dis  1989;  140(  1 ):  1 -3. 

Slutsky  AS.  Mechanical  ventilation.  American  college  of  chest  physi- 
cians consensus  conference.  Chest  1993;  104(6):  1 833- 1 859. 
Appendini  L,  Patessio  A,  Zanaboni  S,  Carone  M.  Gukov  B,  Don- 
ner  CF,  Rossi  A.  Physiologic  effects  of  positive  end-expiratory  pres- 
sure and  mask  pressure  support  during  exacerbations  of  chronic  ob- 
structive pulmonary  disease.  Am  J  Respir  Crit  Care  Med  1994;  149 
(5):1069-1076. 

13.  Meduri  GU.  Abou-Shala  N,  Fox  RC,  Jones  CB.  Leeper  KW,  Wun- 
derink  RG  Noninvasive  face  mask  mechanical  ventilation  in  pa- 
tients with  acute  hypercapnic  respiratory  failure.  Chest  1991:100(2): 
445-454. 


10 


11 


12 


RESPIRATORY  CARE  •  NOVEMBER  '95  VOL  40  NO  1  1 


1147 


Books,  Films, 
Tapes,  &  Software 


Listing  and  Reviews  of  Books  and  Other  Media 

Note  to  publishers:  Send  review  eopies  of  books,  filn 
1 1030  Abies  Lane.  Dallas  TX  75229-4393. 


,  tapes,  and  software  to  RESPIRATORY  CARE, 


Principles  and  Applications  of  Cardio- 
respiratory Care  Equipment,  edited  by 
David  H  Eubanks  and  Roger  C  Bone,  with 
16  contributors.  Hardcover,  394  pages,  il- 
lustrated. St  Louis:  Mosby-Year  Book, 
1994.  S45.95. 

The  editors  of  Principles  and  Appli- 
cations of  Cardiorespiratory  Care  Equip- 
ment attempt  to  go  beyond  the  usual  tech- 
nical explanation  of  equipment  by  including 
clinical  applications  supplied  by  both  physi- 
cian and  therapist  authors.  Medical  students 
and  physicians  who  seek  an  explanation  of 
equipment  used  in  cardiorespiratory  appli- 
cations are  the  book's  intended  audience. 

Chapter  1  details  medical  gas  cylinders, 
regulators,  flowmeters,  and  safety  rules. 
Bulk  and  portable  oxygen  systems  and  air 
compressors  are  explained  in  detail.  The 
diagrams  are  clear  and  easy  to  understand. 
Only  the  addition  of  the  Compressed  Gas 
Association  numbers  would  have  made  the 
chapter  more  complete. 

Methods  of  administrating  medical  gases 
follow  in  logical  sequence  as  Chapter  2.  De- 
vices— from  cannula  to  transtracheal  oxy- 
gen (SCOOP)  catheters  are  clearly  illustrated. 
Photographs  show  their  correct  application 
to  patients.  An  excellent  review  of  heliox  and 
carbogen  is  presented.  One  small  typograph- 
ical error  that  lists  the  Fiq,  of  a  nasal  cannula 
as  0.40-0.44  in  Table  2-5  on  Page  41  is  the 
only  distraction  in  this  chapter. 

Chapter  3  covers  humidity  and  aerosols 
and  includes  excellent  pictures  and  diagrams. 
Metered  dose  inhalers,  spacers,  and  holding 
chambers  are  well  illustrated  with  the  ra- 
tionale for  their  appropriate  use.  This  book 
contains  one  of  the  best  reviews  of  humid- 
ity and  aerosol  devices  that  I  have  read.  Un- 
fortunately, some  of  the  captions  to  the  fig- 
ures are  incorrect.  On  Page  93,  Figure  3-59 
clearly  shows  a  mouthpiece  in  use  while  the 
caption  states  it  is  a  mask.  Also  on  Page  91 
the  text  cites  some  of  the  figures  in  error. 

The  practice  of  using  warmed,  humidified 
gases  to  treat  hypothermia  is  not  supported 
by  citation  of  the  current  literature.  In  fact, 
the  reference  cited  on  Page  56  refers  to  blood 
levels  of  fluorocarbons  in  asthmatic  patients. 

Chapter  4,  Artificial  Airways  and  Tubes, 
uses  the  same  format  of  detailed  pictures  and 
diagrams.  However,  some  figures  and  text 


do  not  agree.  On  Page  134,  the  text  refers 
to  a  tracheostomy  tube  with  a  pressure  lim- 
iting automatic  relief  valve  in  Figure  22B. 
There  is  no  automatic  relief  valve  in  the  di- 
agram. Also,  Figure  4-26  omits  labeling  A 
andB. 

Chapter  5,  Manual  Resuscitators,  Venti- 
lators, and  Breathing  Circuits,  lists  many 
specifications.  The  chapter  covers  primar- 
ily the  reusable  systems  and  does  not  review 
neonatal  systems. 

The  Chatburn  Ventilator  Classification 
System  is  presented  early  in  the  chapter,  with 
a  representative  sample  of  modern  venti- 
lators. It  is  noted  that  "A  more  detailed  de- 
scription of  each  ventilator,  as  defined  by  the 
classification  system  proposed  by  Chatburn 
is  found  in  Table  5-7."  What  is  found  in 
Table  5-7  is  an  inconsistency.  The  table  de- 
scribes flow  as  "decelerating."  Whereas, 
Chatbum  clearly  points  out  that  the  term  "de- 
celerate" is  a  misnomer  and  that  the  term  "ex- 
ponential decay"  is  more  correct.1 

The  explanation  of  the  BEAR  2  is  ex- 
plained based  on  its  similarity  to  the  BEAR 
1,  the  BEAR  1  is  not  covered  in  the  text! 

This  chapter  is  somewhat  difficult  to  read 
because  text  and  related  figures  and  tables 
are  separated — sometimes  by  many  pages. 
Flipping  back  and  forth  adds  to  the  confu- 
sion and  distracts  the  reader  from  informa- 
tion about  each  ventilator. 

On  Page  174.  the  display  and  control 
panel  of  the  BEAR  3  is  rotated. 

The  discussion  on  output  alarms  is  con- 
fusing, on  Page  166.  The  subtopics  under 
"Pressure"  list  mean  airway  pressure  twice 
with  two  different  definitions. 

The  authors  end  the  chapter  with  the 
modes  of  ventilation,  but  they  appear  to  have 
forgotten  that  they  were  following  the  Chat- 
bum  System,  because  there  is  little  similarity. 
The  section  on  airway  pressure  release  ven- 
tilation refers  to  the  PPG  Irisa  ventilator.  It 
also  mentions  the  BiPAP  system  produced 
by  Respironics  Inc  and  includes  the  modes 
of  this  device.  The  explanations  of  these  sys- 
tems are  weak,  and  neither  the  Irisa  or  the 
BiPAP  machines  are  covered  earlier  in  the 
chapter  with  the  review  of  other  ventilators. 

Although  the  chapter  includes  many 
good  diagrams  and  helpful  facts,  overall  it 
contains  less  information  than  each  venti- 
lator's operator's  manual. 


Nonconventional  mechanical  ventilation 
is  covered  in  Chapter  6.  Topics  include  high- 
frequency  ventilation,  bidirectional  jet  ven- 
tilation, intravascular  oxygenation  (IVOX), 
extracorporeal  carbon  dioxide  removal 
(ECOsR),  and  diaphragmatic  pacing,  plus 
the  Bird  intrapulmonary  percussive  venti- 
lator, volumetric  diffusive  respiration  (VDR). 
and  the  APT  1010. 

Extracorporeal  membrane  oxygenation 
(ECMO)  is  explained  with  clear  diagrams. 
The  section  on  IVOX  is  informative  and  thor- 
ough. The  review  of  ECO:R  is  also  well 
done  with  excellent  figures,  procedure  tech- 
niques, and  rationale. 

Cardiopulmonary  Bedside  Monitoring, 
Chapter  7,  focuses  on  ventilatory  monitor- 
ing, gas  exchange,  and  hemodynamic  mon- 
itoring. The  schematic  of  the  Siemens  900C 
on  page  297  (inappropriately  labeled  300C) 
distracts  from  the  theme  of  the  chapter.  Also 
on  Page  313.  Figure  7-28  reads  ?2co:  instead 
ofPaCOf 

The  method  of  measuring  maximum  in- 
spiratory pressure  (MIP)  is  well  explained 
but  respirometers  are  not  included.  Other  de- 
vices that  measure  volume — from  bedside 
spirometers  to  incentive  spirometers — are 
included.  A  wealth  of  information  on  meta- 
bolic carts,  transcutaneous  devices,  capno- 
graphs,  and  hemodynamic  monitoring  in- 
struments is  included. 

Cardiopulmonary  Laboratory  Instru- 
mentation reviews  pulmonary  function  test- 
ing, cardiovascular  and  pulmonary  stress  test- 
ing, blood  gas  analysis,  bronchoscopy,  and 
sleep  disorders  testing. 

This  book  can  be  a  valuable  addition  to 
any  hospital  departmental  reference  shelf  be- 
cause of  the  wide  variety  of  topics  includ- 
ed. It  provides  practical  and  clinically  rel- 
evant information  that  is  difficult  to  find  in 
most  standard  texts. 

Fran  Piedalue  RRT 

University  Hospital 
Denver,  Colorado 


REFERENCES 

I .  Chatburn  RL.  A  new  system  for  under- 
standing mechanical  ventilators.  Respir 
Care  1991;36(  10):  1 123-1 155. 


1148 


Respiratory  Carf.  •  November  '95  Vol  40  No  1 1 


Letters  addressing  topics  of  current  interest  or  material  in  RESPIRATORY  CARE  will  be  considered  for  publication.  The  Editors  may  accept  or 
decline  a  letter  or  edit  without  changing  the  author's  views.  The  content  of  letters  as  published  may  simply  reflect  the  author's  opinion  or  in- 
terpretation of  information — not  standard  practice  or  the  Journal's  recommendation.  Authors  of  criticized  material  will  have  the  opportunity 
to  reply  in  print.  No  anonymous  letters  can  be  published.  Type  letter  double-spaced,  mark  it  "For  Publication,"  and  mail  it  to  RESPIRATORY 
CARE,  1 1030  Abies  Lane.  Dallas  TX  75229-4593. 


Letters 


'Bad  Press'  for  RCPs? 

Because  I  am  active  both  as  a  paramedic 
and  a  respiratory  care  instructor,  I  read  with 
interest  an  abstract  reprinted  from  Chest  that 
appeared  on  Page  798  of  the  August  issue 
of  the  Journal,  relating  one  hospital's  ex- 
perience with  having  paramedics  perform 
intubations  during  cardiac  arrests.  After  read- 
ing the  abstract,  1  proceeded  to  retrieve  and 
read  the  complete  paper.1  Alas — fortunately 
or  unfortunately — what  the  abstract  does  not 
include  is  the  inaccurate  and  even  deroga- 
tory depiction  of  respiratory  care  practitioners 
(RCPs)  that  appears  in  the  discussion  sec- 
tion of  that  paper.  On  Page  1659,  the  authors 
state  that  respiratory  therapists  "are  in  high 
demand,  with  a  high  turnover  rate  and  a  gen- 
eral unavailability  and  unwillingness  to  work 
nights..."  (I  added  the  italics  for  emphasis.) 

Our  AARC  leadership  is  aware  of  the 
paper  and  its  assertions,  but  chartered  affiliate 
leaders  and  RCPs  at  the  bedside  also  need 
to  be  aware  of  them.  We  need  to  be  vigilant 
about  countering  such  incorrect  and  possi- 
bly dangerous  assertions. 

In  the  reported  study,  paramedics  had  the 
fastest  response  time  of  a  group,  consisting 
of  paramedics,  certified  nurse  anesthetists, 
anesthesiologists,  and  other  physicians.  Ther- 
apists were  not  included  in  the  group.  The 
authors  advocated  the  use  of  paramedics  over 
therapists  because  of  costs.  However,  as  with 
many  scenarios,  using  lower  paid  personnel 
is  probably  false  economy.  Because  thera- 
pists would  be  involved  in  resuscitation  any- 
way, "paramedics  . . .  hired  primarily  for  in- 
tubations" could  mean  more  personnel  in  an 
era  in  which  numbers  of  personnel  are  being 
cut  and  would  make  the  paramedic  pretty 
much  a  'one-trick  pony'  when  multiskilling 
is  becoming  the  rule.  The  authors  do  say  that 
the  paramedics  would  be  able  to  assist  with 
venous  line  placement,  drug  administration, 
and  defibrillation — duties  that  RCPs  are  as- 
suming in  many  institutions. 

Robert  R  Fluck  Jr  MS  RRT 

Clinical  Coordinator 

Department  of  Respiratory  Care 

&  Cardiorespiratory  Sciences 

State  University  of  New  York 

Health  Science  Center 

Syracuse,  New  York 


REFERENCES 

1.  SmaleJR,  Kutty  K,  Ohlert  J,  Cotter  T.  En- 
dotracheal intubation  by  paramedics  dur- 
ing in-hospital  CPR.  Chest  1995;  107(6): 
1655-1661. 


Therapeutic  Touch 
&  Respiratory  Therapy 

In  1993, 1  took  a  workshop  in  Therapeutic 
Touch;  this  experience  has  changed  my  out- 
look on  western  medicine  and  opened  my 
eyes  to  the  potential  available  for  healing  on 
all  levels,  if  we  integrate  medicine  as  it  is 
and  various  holistic  approaches. 

I  have  been  a  respiratory  therapist  (RT) 
for  24  years  and  am  increasingly  frustrated 
with  the  emphasis  on  technology  and  a  seem- 
ing lack  of  concern  for  preventive  practices 
and  holistic  approaches  to  healing  that  pre- 
vail in  Western  medicine.  We  seem  to  want 
to  alleviate  symptoms,  not  promote  health. 
I  believe  it  is  possible  to  integrate  holistic 
modalities  with  even  acute  care  medicine. 

For  several  years  I  have  been  attracted 
to  holistic  practices  and  have  been  surprised 
to  find  that  Therapeutic  Touch  is  being  used 
in  many  hospitals  and  medical  facilities. 
Therapeutic  Touch  was  developed  by 
Kreiger  in  19721  and  is  now  being  taught  in 
colleges  and  health-care  facilities.  Thera- 
peutic Touch  is  within  the  health  profes- 
sionals' scope  of  practice  in  some  hospitals. 
Several  of  these  facilities  have  policies  and 
procedures  in  place  and  offer  training  work- 
shops on  this  topic. 

It  is  not  within  the  scope  of  this  letter  to 
explain  the  procedure  of  Therapeutic  Touch, 
for  one  must  take  a  class  to  be  appropriately 
instructed.  However,  the  basic  premise  is 

Therapeutic  Touch  is  based  on  the  idea 
that  human  beings  are  energy  in  the  form 
of  a  field.  When  you  are  healthy,  that  en- 
ergy is  freely  flowing  and  balanced.  In 
contrast,  dis-ease  is  a  condition  of  ener- 
gy imbalance  or  disorder.  The  human  en- 
ergy field  extends  beyond  the  level  of  the 
skin  and  the  Therapeutic  Touch  practi- 
tioner attunes  himself  or  herself  to  that  en- 
ergy using  the  hands  as  sensors.2 

In  disease,  trauma,  or  anxiety  states  the 
energy  field  around  the  body  becomes  un- 


balanced. The  practitioner  uses  his/her  hands 
to  assess  and  rebalance  this  energy  field. 
Much  of  this  energy  work  is  done  without 
actually  touching  the  body  and,  in  fact,  all 
of  it  can  be  so  done.  (As  an  added  note,  this 
practice  also  works  well  with  animals). 

Research  supports  that  Therapeutic  Touch 
can  decrease  pain,1-3  decrease  anxiety,4,5  de- 
crease diastolic  blood  pressure,6  accelerate 
the  body's  own  healing  process,7  and  pro- 
mote wellness.  Kreiger  stated  that  "Thera- 
peutic Touch  can  be  learned  by  anyone  who 
has  a  sincere  desire  to  help  others." 

In  most  hospitals.  Therapeutic  Touch  is 
provided  by  nurses — because  it  was  initially 
started  by  a  nurse  for  nurses;  because  they 
have  a  larger  body  of  persons  available;  and 
because  the  position  they  hold  in  the  culture 
of  medicine  gives  them  innumerable  op- 
portunities for  providing  the  service.  How- 
ever, in  many  places  it  is  considered  a  multi- 
disciplinary  practice  that  is  not  confined  to 
nursing  but  can  be  practiced  by  anyone  who 
has  attended  a  Therapeutic  Touch  workshop 
(generally  a  12-hour  class). 

I  have  found  Therapeutic  Touch  (es- 
pecially its  calming  effect)  to  help  patients 
with  acute  asthma,  and  I  have  used  this 
modality  for  patients  with  congestive  heart 
failure,  headaches,  postoperative  pain,  mus- 
cle cramps,  gastric  pain,  and  other  con- 
ditions. I  have  found  that  administering 
Therapeutic  Touch  saves  time  because  pa- 
tients tend  to  be  less  anxious  and  more  re- 
laxed. Some  patients  may  accept  therapy 
that  they  have  been  refusing  because  of 
pain  or  anxiety. 

Therapeutic  Touch  may  be  a  new  concept 
for  RTs  who  are  technically  oriented.  How- 
ever, I  have  found  that  interacting  with  patients 
on  a  human  and  healing  basis  makes  my  job 
more  satisfying.  Medicine  is  entering  a  new 
phase  in  which  traditional  medicine,  although 
necessary,  is  being  viewed  as  only  one  avail- 
able option.  Traditional  medicine  and  holis- 
tic approaches  work  well  together.  In  my  hos- 
pital, we  now  have  a  respiratory  therapist,  a 
physical  therapist,  a  physician,  and  several 
nurses  administering  Therapeutic  Touch,  while 
others  await  the  next  class. 

Stephanie  Haines  RRT 

Mad  River  Community  Hospital 
Areata,  California 


RESPIRATORY  CARE  •  NOVEMBER  '95  VOL  40  NO  1  1 


1149 


Letters 


REFERENCES 

1 .  Professional  Associates  Inc.  Nurse  heal- 
ers information  brochure.  Allison  Park  PA. 

2.  Meehen  TC.  The  effect  of  therapeutic 
touch  on  the  experience  of  acute  pain  in 
post  operative  patients.  Dissertation  Abs 
Int46.  795B. 

3.  Keller  E.  Bzdek  VM.  Effects  of  Thera- 
peutic Touch  on  tension  headache  pain. 
NursRes  1986;35(2):101-106. 

4.  Heidt  P.  Effect  of  therapeutic  touch  on  the 
anxiety  level  of  hospitalized  patients.  Nurs 
Res  1979;(4):660-662. 

5.  Quinn  JF.  Therapeutic  touch  as  an  ener- 
gy exchange:  testing  the  theory.  Adv  Nurs 
Sci  1984;6(2):42-49. 

6.  Quinn  JF.  Therapeutic  touch  as  an  ener- 
gy exchange:  replication  and  extension. 
Nurs  Sci  Q  1989;(2):79-87. 

7.  Wirth  DP.  Richardson  JT.  Eidelman  WS, 
O'Malloy  AC.  Full  thickness  dermal 
wounds  treated  with  non-contact  thera- 
peutic touch:  a  replication  and  extension. 
Complementary  Therapies  in  Medicine 
1993;(1):127-132. 


RESOURCES  FOR 
THERAPEUTIC  TOUCH* 

Arizona  State  University  Dept  of  Nursing, 

Tempe  AZ  85287-2602' 

Ashland  Community  Health  Center,  245  4th 

St,  Ashland  OR  97521* 

Bristol  Hospital,  PO  Box  529,  Bristol  CT 

06011-0529' 

Calgary  General  Hospital,  841  Center  Ave 

E  Calgary  AB,  T2E0A1  Canada'* 

Chaffey  College,  Dept  of  Physical  Educa 

tion/Wellness  Division,  5885  Haven  Ave,  Ran 

choCA  91701-0430* 

Cleveland  State  University,  Dept  of  Contin 

uing  Education,  E  24th  &  Euclid  Ave,  Cleve 

land  OH  441 15' 


Community  Homewell  Home  Health.  1971 
State  Route  20,  Sedro  Wooley  WA  98284' 
Cope  Foundation,  Dept  of  Inservice  Educa- 
tion. Bonnington,  Montenolte.  Cork.  Ireland* 
Denver  General  Hospital,  777  Bancock  St, 
Denver  CO  80204'* 

Eastern  State  Hospital.  4601  Iron  Bound  Rd, 
Williamsburg  VA  23187' 
Georgian  College.  Dept-School  of  Continu- 
ous Learning,  1  Georgian  Drive,  Barre.  On- 
tario L4M3X9,  Canada' 
Jersey  City  State  College,  Dept  of  Nursing. 
2039  Kennedy  Blvd.  Jersey  City  NJ  07305' 
Mad  River  Community  Hospital,  3800  Janes 
Rd,  Areata  CA  95521' 
Masonic  Retirement  Center,  23660  Marine 
View  Dr,  S  Des  Moines  WA  98198* 
Mercy  Hospital.  3663  S  Miami  Ave,  Miami 
FL  33133** 

Midcoast  Hospital.  58  Baribeau  Dr,  Brunswick 
ME  04011* 

Murray  State  University.  Dept  of  Nursing,  PO 
Box  9,  Murray  KY  42071** 
Ochsner  Medical  Foundation  Hospital,  1516 
Jefferson  Highway.  New  Orleans  LA  701 2 1  '* 
Oregon  Health  Science  University,  Dept  of 
the  School  of  Nursing  at  Southern  Oregon 
State  College,  1250  Siskiyou,  Ashland  OR 
97520'* 

Pembrook  Civic  Hospital,  425  Cecelia  St. 
Pembrook,  Ontario  K8A1S7  Canada' 
Presbyterian  St  Lukes  Medical  Center,  1719 
E  19th  Ave,  Denver  CO  80218" 
Riverside  Methodist  Hospital.  3535  Olentangy 
Rd,  Columbus  OH  43214'* 
Sacramento  City  College,  Dept  of  Commu- 
nity Education,  3085  Freeport  Blvd.  Sacra- 
mento CA  95822* 

San  Francisco  State  University.  Dept-Insti- 
tute  for  Holistic  Healing  Studies,  1600  Hol- 
loway  Ave,  San  Francisco  CA  94132* 
Southern  New  Hampshire  Regional  Medical 
Center,  PO  Box  2014,  Nashua  NH  03060* 
St  Joseph's  Health  Center,  30  The  Queen's 
Way,  Toronto,  Ontario  M6R1B5  Canada* 


•  St.  Mary's  Hospital,  Guy  Park  Ave,  Ams- 
terdam NY  12010 

•  Toronto  East  General  Hospital,  825  Coxwell 
Ave.  Toronto,  Ontario  M4C3E7  Canada* 

•  University  of  Alabama  at  Birmingham.  UAV 
Station,  Dept  of  Nursing  1701  University  Blvd. 
Room  GO  10.  Birmingham  AL  35294* 

•  University  of  Colorado,  Dept  of  Nursing,  4200 
E  9th  Ave.  Campus  Box  C288,  Denver  CO 
80262' 

•  University  of  Hawaii  at  Manoa,  Dept  of  Con- 
tinuing  Education  and  Community  Service, 
2530  Dole  Street,  Honolulu  HI  96822* 

•  University  of  Victoria.  Dept-School  of  Nurs- 
ing, PO  Box  1700  MS  7955,  Victoria  BC 
V8W2Y2  Canada' 

•  University  of  Western  Ontario,  Dept-Facul- 
ty  of  Part-Time  Continuing  Education.  Rm  23 
Stevenson-Lawson  Bldg,  London,  Ontario 
N6A5B8,  Canada' 

•  Virginia  Mason  Medical  Center.  Dept  of  Nurs- 
ing Education,  1 100  9th  Ave,  PO  Box  900  c/o 
HNR9RHU,  Seattle  WA  981 1 1' 

•  Winthrop  University  Hospital,  259  First  St. 
MineolaNY  11501" 

•  Winthrop  University  Hospital,  259  First  St. 
MineolaNY  11511 

*Supplied  by  the  Nurse  Healers  and  Professional 
Associates  Inc.  PO  Box  444,  Allison  Park  PA 
15101-0444.  'Offer  educational  program.  'Have 
policies  and  procedures  in  place. 

SUGGESTED  READING 

•  Brennan  B.  Hands  of  light.  New  York:  Ban- 
tam. 1987. 

•  Gerber  R.  Vibrational  medicine:  new  choic- 
es to  heal  ourselves,  Santa  Fe:  NM  Bear  &  Co. 
1988. 

•  Kreiger  D.  The  therapeutic  touch.  Englewood 
Cliffs:  Prentice-Hall,  1979. 

•  Kreiger  D.  Accepting  your  power  to  heal:  the 
personal  practice  of  therapeutic  touch.  Santa 
Fe:  NM  Bear  &  Co,  1993. 


1150 


RESPIRATORY  CARL  •  NOVEMBER  '95  VOL  40  NO  1  1 


Respiratory  Care 
Open  Forum  Abstracts 


FACE  TO  FACE  WITH  CHANGE 

A  comprehensive  look  at  important  case  reports,  the  latest  methods  and  device  evaluations, 

plus  current  clinical  studies  from  around  the  world — All  are  part  of  the  1995  Respiratory 

Care  Open  Forum.  More  than  160  abstracts  will  be  presented  during  this  year's 

Minisymposia;  the  13  sessions  and  their  moderators  are  listed. 

An  index  of  the  authors,  with  Presenters  designated  in  boldface  type,  appears  on  Page  1210. 


Teach  Your  Students  Well! 

Educating  Practitioners,  Patients,  &  Colleagues 

Moderators:  Timothy  Op't  Holt  EdD  RRT 
&  Ralph  E  Bartel  MEd  RRT 

Cases,  Series,  &  Clinical  Trials: 
Patients  on  Mechanical  Ventilation 

Moderators:  Robert  L  Chatburn  RRT 
&  Sherry  E  Courtney  MD  MS 

Clinical  Practice  Guidelines  in  Action! 

Moderators:  James  K  Stoller  MD 
&  Lucy  Kester  MBA  RRT 

It's  a  Basic  Black  Dress: 
Something  for  Everyone 

Moderators:  Mark  C  Wilson  MD 
&  John  M  Graybeal  CRTT 

Role  Expansion  &  Work  Redesign: 
Implications  for  the  Profession 

Moderators:  William  Dubbs  MBA  RRT 
&  Richard  M  Ford  BS  RRT  RCP 

Work  &  Weaning  What's  the  Buzz? 

Moderators:  Robert  M  Kacmarek  PhD  RRT 
&  Robert  S  Campbell  RRT 


Benches  to  Trenches: 
Calibration,  Validation,  &  Application 

Moderators:  Charles  G  Durbin  Jr  MD 
&  Thomas  D  East  PhD 

Aerosols — A  Foggy,  Foggy  Dew 

Moderators:  Joseph  L  Rau  Jr  PhD  RRT 
&  Michael  McPeck  BS  RRT 

What  Part  of  NO  Don't  You  Understand? 

Moderators:  Dean  Hess  PhD  RRT 
&  Peter  Betit  BS  RRT 

How  Do  They  Do  What  They  Do? 
Devices  &  Systems 

Moderators:  Jon  Nilsestuen  PhD  RRT 
&  Thomas  A  Barnes  EdD  RRT 

To  Boldly  Go  Where  No  One  Has  Gone  Before: 

TGI  &  PLV 

Moderators:  Mark  Heulitt  MD 
&  David  J  Pierson  MD 

So  You  Think  Money  Grows  on  Trees? 
Containing  the  Costs  of  Care 

Moderators:  Shelley  C  Mishoe  PhD  RRT 
&  Patrick  J  Dunne  MEd  RRT 

Ins,  Outs  &  Subtleties  of  Mechanical  Ventilation 

Moderators:  Richard  D  Branson  RRT 
&  Neil  R  Maclntyre  MD 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


151 


Saturday,  December  2,  12:45-2:40  pm  (Rooms  230C-D) 


SMOKING  HABITS  OF  RESPIRATORY  CARE 
PRACTITIONERS  IN  OHIO,  INDIANA,  AND  KENTUCKY. 
Debra  K.  Kasel.  M.Ed..  RRT.  Bradley  R.  A.  Wilson,  Ph.D., 
Donald  I.  Wagner,  Ph.D.,  University  of  Cincinnati,  Cincinnati, 
Ohio.  BACKGROUND:  The  purpose  of  this  study  was  to 
determine  the  smoking  rate  among  respiratory  care 
practitioners  (RCP's)  who  attended  the  annual  Region  Two 
conference,  and  to  determine  the  effect  RCP  educational 
preparation  had  on  smoking  behavior  among  these  RCP's, 
ana  to  assess  how  psychological  and  social  factors  affected 
RCP's  smoking  behavior.  METHODS:  The  study  was 
conducted  at  the  annual  Ohio,  Indiana,  and  Kentucky  Region 
Two  conference  held  May  1 1-13,  1994,  at  Cincinnati,  Ohio. 
Participants  were  asked  to  complete  a  questionnaire  at 
registration  and  return  the  questionnaire  to  boxes  located  at 
the  doors  to  the  conference  hall.  RESULTS:  One  hundred 
fifty-two  usable  questionnaires  were  obtained  from  1000 
participants.  The  smoking  rate  among  RCP's  was  26.0%.  A 
95%  confidence  interval  among  the  general  population  was 
25.0%-  26.1%,  therefore  the  smoking  rate  among  RCP's  at 
this  regional  conference  falls  within  this  confidence  interval 
for  the  general  population.  The  majority  of  respondents  had 
completed  an  associate's  degree  56.3%,  21 .2%  had 
completed  a  baccalaureate  degree,  12.6%  had  a  high  school 
diploma,  and  9.9%  had  completed  a  master's  degree.  The 
chi-square  (3,  ii=  151)  =  2.403,  p.  >  .05,  showed  no  difference 
among  education  preparation  and  smoking  rate.  The 
analysis  of  variance  on  psychological  and  social  factors  and 
smoking  habits  showed  no  difference  £  (1 ,  61 )  =  .570,  p.  >  .05. 
CONCLUSION:  RCP's  who  attended  the  annual  Region  Two 
conference  had  the  same  smoking  rate  as  the  general 
population,  educational  preparation  had  no  affect  on  the 
smoking  rate  among  these  RCP's,  and  psychological  and 
social  factors  did  not  influence  smoking  behavior  of  RCP's. 


PRELIMINARY  EVALUATION  OF  A  COMMUNITY  QUIT  &  WIN  SMOKING  CESSATION 

PROGRAM 

Tim  Blanchette  MS.  RRT  Maine  Medical  Center,  Portland,  ME 

Introduction:  Quit  and  Win  smoking  cessation  contests  have  been  conducted  in  businesses, 
communities,  states  and  even  entire  countries  as  etlective  mass-reach  smoking  cessation 
strategies.  Most  individuals  quit  smoking  on  their  own,  are  unwilling  to  attend  group  clinics  but 
are  willing  to  participate  in  minimal  contact  programs.  This  is  such  a  program.  Methods:  Our 
respiratory  care  department  organized  a  community  coalition  and  developed  plans  for 
implementing  a  mass-reach  Quit  Smoking  and  Win  lottery  in  the  Portland,  Maine  vicinity  (area 
pop:  166,200  -  27%  smokers).  Essentially,  current  smokers  who  registered  (or  the  program  and 
quit  smoking  for  five  weeks  were  eligible  for  cash  prizes  ol  $500,  $250,  and  $1 00  via  a  lottery. 
Their  "helpers'  were  also  eligible  for  prizes.  A  small  grant,  local  businesses,  and  organizations 
provided  funding  for  prizes  and  Maine  Medical  Center  provided  other  "in  kind"  contributions.  All 
participants  were  professed  smokers  {>  5  cigarettes/day)  with  "helpers"  to  verify  their  smoking 
status  and  help  them  quit  All  participants  were  required  to  quit  smoking  by  February  14, 1995 
and  remain  nonsmokers  until  the  first  day  of  spring  [-  5  weeks).  Program  publicity  through  a 
limited  mass  media  campaign,  posters,  and  brochures  primarily  in  hospitals  and  businesses 
began  in  early  January.  Registration  forms  were  available  at  local  pharmacies  and  a  college 
fitness  center.  Anyone  quitting  after  January  1 , 1 995  was  eligible  for  the  contest  as  long  as  they 
maintained  abstinence  through  the  five  week  quit  period  ending  March  20.  Upon  registration,  all 
registrants  were  sent  a  Quit  Kit  with  self-help  smoking  cessation  booklets  (one  for  quitter,  one 
tor  helper)  and  a  letter  noting  local  cessation  resources  Two  additional  letters  of 
encouragement  with  "quit  tips"  and  further  information  were  sent  to  participants  during  the  5 
week  quft  period.  In  order  to  verify  their  non-smoking  status  and  be  eligible  for  prizes, 
registrants  were  required  to  appear  for  an  exhaled  CO  test  a  few  days  prior  to  the  program 
finale.  Three,  six,  and  twelve  month  followups  are  planned  Results:  One  hundred  seventy-six 
Portland  area  smokers  (with  helpers)  registered  for  the  Quit  and  Win  program.  There  were  69 
male  and  107  female  contestants  ranging  in  age  from  14-69  years.  Mean  age  was  38,1±  10.5 
years.  Sixty  participants  (37  female.  23  male  or  34%  of  registrants)  stopped  smoking  for  the  five 
required  weeks  and  were  eligible  for  prizes.  At  the  program's  conclusion,  all  successful  quitters 
completed  program  questionnaires.  78%  felt  the  program  encouraged  them  to  quit  smoking, 
though  73%  said  they  would  have  quit  even  without  the  program  Successful  quitters  provided 
much  positive  feedback  and  all  telt  the  Quit  &  Win  program  was  worthwhile  for  them. 
Conclusions:  Quit  and  Win  campaigns  can  be  coordinated  through  respiratory  care 
departments  and  reach  larger  numbers  of  smokers  than  conventional  smoking  cessation 
techniques.  It  is  difficult  to  determine  if  the  contest  increased  the  background  smoking 
cessation  rate  but  short  term  quit  rates  were  impressive  and  the  program  provided  public 
relations  benefits  for  the  hospital. 

OF-95-103 


RESPIRATORY  THERAPISTS  PROVIDE  SMOKING 
CESSATION  COUNSELING  TO  HOSPITALIZED 
SMOKERS 

Linda  Allawav.  B.S..RRT..  Homedco.  Portland.  Ore. 

Victor  J.  Stevens,  Ph.D.,  Kaiser  Permanente  Center  for  Health 

Research,  Portland,  Ore. 

An  earlier  study  showed  that  a  brief,  bed-side  counseling 
session  using  master's  degree  level  smoking  counselors 
significantly  increased  one-year  quit  rates  among 
hospitalized  smokers  (Stevens,  et  al.,  Medical  Care, 
1993;31:65-72.).  Can  hospital  respiratory  therapists  be  trained 
to  successfully  perform  the  same  intervention?  A  NCI- 
funded,  randomized,  controlled  clinical  trial  has  tested  the 
practicality  and  effectiveness  of  this  intervention  model  in 
two  large  hospitals  using  respiratory  therapists  as  the 
smoking  counselors.  Elements  of  the  intervention  program 
include  assessment  of  readiness  to  quit  smoking  (stage  of 
change),  a  20-minute  counseling  session  tailored  to  the 
patient's  stage  of  change,  a  10-minute  video  tape,  a  variety  of 
written  materials  and  a  follow-up  phone  call  one  to  three 
weeks  after  leaving  the  hospital.  Patient  acceptance  of  the 
respiratory  therapy  counselors  has  been  high  with  only  3% 
of  the  first  525  patients  refusing  to  see  the  counselors.  Of 
those  patients  seen,  (n=359),  71  %  expressed  a  strong  interest 
in  quitting  smoking,  53%  resolved  to  not  smoke  again  and 
43%  reported  abstinence  from  tobacco  at  a  follow-up 
interview  one  to  three  weeks  after  leaving  the  hospital.  The 
hospital  based  intervention  was  completed  one  year  ago  and 
current  data  regarding  smoking  cessation  in  the  study 
groups  is  being  collected  and  analyzed  to  determine  success 
in  converting  a  successful  temporary  cessation  during 
hospitalization  with  a  structured  intervention  by  respiratory 
therapist  to  long-term  abstinence  from  cigarette  smoking. 


KNOWLEDGE  LEVELS  OF  RESPIRATORY  CARE  PRACTITIONERS 
REGARDING  NICOTINE  INTERVENTION  IN  THE  HOSPITAL 
SETTING.  Dunlew  CL.EdD.RRT.  Capots  MD,  Hensley  KA. 
The  Ohio  State  University,  Columbus,  Ohio. 
Introduction:  Nicotine  intervention  in  the  hospital 
setting  is  often  performed  by  nursing  staff.  In 
light  of  the  changing  environment  in  health  care, 
and  because  they  work  closely  with  patients  who 
have  smoking  related  diseases/disorders,  nicotine 
intervention  is  a  task  that  could  be  performed  by 
the  respiratory  care  practitioner  (RCP) .  The 
purpose  of  this  study  was  to  determine  whether  RCPs 
are  knowledgeable  enough  to  undertake  this 
responsibility  without  retraining.  Methods:  A  25- 
item  test  was  developed  by  the  investigators, 
designed  to  determine  subjects'  knowledge  of 
nicotine  intervention  as  it  relates  to  the 
hospitalized  patient  (signs  &  symptoms  of  nicotine 
withdrawal,  determining  level  of  addiction, 
readiness  to  quit,  effect  of  a  non-smoking 
environment,  etc.).  8  experts  gave  feedback  to 
ensure  content  validity.  Cronbach's  alpha  was 
performed  for  reliability  (0.76),  using  pilot  tests 
from  30  subjects.  6  demographic  questions  were  also 
included.  As  a  result  of  a  power  analysis  (0.80), 
350  subjects  were  randomly  selected  from  a  list  of 
5280  licensed  RCPs  in  the  state  of  Ohio.  Subjects 
were  instructed  no  to  consult  outside  resources 
when  completing  the  test.  Means  &  standard 
deviations  were  calculated  for  test  scores;  one-way 
ANOVA  was  performed  to  compare  test  scores  for  each 
demographic  variable.  Results:  191  tests  were 
returned  (55%  response) .  81%  of  respondents 
received  a  failing  score.  One-way  ANOVA  revealed 
that  no  single  demographic  variable  accounted  for  a 
statistically  significantly  higher  score  (p  value 
ranging  from  0.067  to  0.835).  Discussion:  The 
results  indicate  that  RCPs  are  not  currently  ready 
to  take  on  the  responsibility  for  nicotine 
intervention  of  the  hospitalized  patient  without 
some  form  of  further  training  or  retraining. 


1152 


Respiratory  Care  •  Novhmbkr  '95  Vol  40  No  1 1 


Saturday,  December  2,  12:45-2:40  pm  (Rooms  230C-D) 


ASTHMA  CARE  EDUCATION  IN  SPORTS  (ACES) .  Dunlew  CL, 
EdD .  RRT .  The  Ohio  State  Univ. ,  Columbus,  OH 
Introduction:  Given  that  students  with  exercise- 
induced  asthma  (EIA)  comprise  approximately  5%  of 
the  school-age  population,  it  would  seem  logical 
that  coaches  and  physical  education  (PE)  teachers 
be  informed  of  the  special  circumstances  brought  to 
their  classes/teams  by  teens  with  asthma.  The 
medical  literature  reveals  that  almost  all 
asthmatics  are  prone  to  asthma  triggered  by  even 
moderate  levels  of  exercise.  PE  teachers  and 
coaching  staff  are  the  adult  supervisors  for 
school-related  physical  activity  —  they  need  to 
know  how  to  respond  appropriately,  should  one  of 
their  students  experience  EIA  during  or  following 
physical  exercise.  The  purpose  of  this  study  was  to 
determine  the  effectiveness  of  ACES.  Methods:  468 
high  school  coaches  and  PE  instructors  in  central 
Ohio  participated  in  the  ACES  program.  Prior  to 
attending  the  program,  subjects  completed  a  15-item 
questionnaire  designed  to  assess  their  knowledge 
about  asthma,  as  well  as  a  17-item  survey  designed 
to  elicit  information  about  their  attitudes 
regarding  asthma  &  asthmatic  students.  ACES 
consisted  of  lectures  and  demonstrations.  Subjects 
also  received  a  30-minute  audiotape  and 
instructional  packet  highlighting  important 
information  about  asthma.  Subjects  repeated 
identical  testing  6  weeks  after  completion  of  the 
ACES  program.  Means  &  SD  were  calculated,  and 
paired,  2-tailed  t-tests  were  performed  in  order  to 
detect  differences  between  pre-  and  post  test 
scores;  p  <  0.05  was  considered  statistically 
significant.  Results:  387  subjects  completed  post- 
testing  (83%)  .  T-tests  revealed  a  statistically 
significant  improvement  in  both  knowledge  scores  (p 
<  0.01)  and  attitudes  about  asthma  (p  <  0.01)  . 
Discussion:  By  educating  the  physical  education 
instructors  and  coaching  personnel  about  asthma,  we 
benefit  both  student  and  teacher,  which  ultimately 
translates  to  optimal  care  for  asthma. 


NICOTINE  INTERVENTION  IN  THE  CURRICULA  OF 
RESPIRATORY  CARE  PROGRAMS.  Dunlew  CL.  EdD.  RRT. 
Male  N.  The  Ohio  State  Univ.,  Columbus,  OH. 
Introduction:  As  Respiratory  Care  (RC)  educational 
programs  prepare  for  the  21st  century,  they  need  to 
be  responsive  to  the  current  health  care  agenda, 
which  places  greater  emphasis  than  ever  before  on 
health  promotion.  Because  Respiratory  Care 
Practitioners  (RCPs)  devote  a  great  deal  of  time  to 
the  care  of  patients  with  smoking-related  diseases, 
it  would  seem  logical  that  RC  programs  prepare 
graduates  to  perform  nicotine  intervention.  The 
purpose  of  this  study  was  to  determine  the  extent 
to  which  RC  programs  include  nicotine  intervention 
in  their  curricula.  Methods:  142  RC  programs  were 
randomly  selected  from  the  1994  JRCRTE  therapist 
program  list  to  participate  in  the  study.  Subjects 
were  asked  to  complete  a  25-item  questionnaire  that 
included  information  about  various  aspects  of 
nicotine  addiction/ intervention  including 
physiology,  incidence,  various  methods  of  smoking 
cessation,  signs/symptoms  of  withdrawal,  and  coping 
mechanisms.  The  questionnaire  also  asked  for 
demographic  information  concerning  RC  program 
level,  hrs.  devoted  to  this  topic,  etc.  Percentages 
for  each  item  were  calculated.  Results:  103 
questionnaires  were  returned  (73%).  74%  of  the  RC 
programs  surveyed  included  nicotine  intervention  in 
their  curricula  to  some  degree  (a  mean  of  3.1 
classroom  hours;  <  1  lab  hour;  1.75  clinical 
hours) .  Topics  most  often  included  were  those 
pertaining  to  incidence  and  physiologic  effects  of 
smoking.  Less  than  25%  of  respondents  reported  that 
they  include  information  about  recognizing 
withdrawal  symptoms ,  determining  level  of 
addiciton,  readiness  to  quit,  developing  a  nicotine 
intervention  program,  or  coping  strategies  for  the 
abstinent  smoker .  Discussion:  In  order  to  produce 
RC  graduates  who  are  able  to  function  effectively 
in  a  competetive  healthcare  environment,  education 
programs  need  to  include  a  comprehensive  study  of 
nicotine  intervention  in  their  curricula. 


EFFECT  OF  EDUCATION  ON  IN  APPROPRIATE  ARTERIAL  BLOOD  CAS 

ACQUISITION  IN  A  SURGICAL  ICU 

John  Sestito,  BA.RRT.  Michael  SBDtoro,BS,RRT,Lynda  GndwelL  MS.RRT, 

Harold  Palevsky.  MD  .David  Shulkm.M  D  .  Susan  Craemer,  RRT.  John  Hansen- Flaschen.M.D. 

University  ol  Pennsylvania  Health  System,  Philt. .Pa. 

JNT  RODl  CTION   The  purpose  of  thb  study  was  to  eiamlne  the  effect  of  an  educational 

Intervention  conducted  by  respiratory  therapists,  nurses,  physicians  and  administrators.  The 

Intervention  included  the  formulation  aod  publication  of  clinical  guide  Lin  es,dlscusston  of  these 

protocols  at  staff  meetings  and  incorporation  of  new  practices  into  unit  and  hospital  C."OI 

programs.  METHODS:  Clinical  guidelines  were  formulated  for  arterial  blood  gas  sampling  by  a 

multidisclpllnary  committee.  Guidelines  were  disseminated  throughout  the  surgical  intensive 

care  unit  (SICU)  and  subsequent  staff  meetings  were  held  to  discuss  these  guidelines.  Indications 

for  obtaining  ABG's  in  the  SICU  Tor  a  one  week  time  before  and  after  intervention. 

RESULTS:  A  total  of  596  ABG's  were  acquired  during  the  study  period.  Data  was  compared 

for  (he  periods  pre  and  post  Implementation  of  guidelines. 

Percentage  obtained  with  a  physician  ordered  ABG's  are  shown: 

1993  (465  ABG's  sampled)  1994  (596  ABG's  sampled) 

WITHOUT  PHYSICIAN  ORDERS  (PO) 

262  (56.3%)  370  (62%) 

WITH  PHYSICIAN  ORDER 

203(43.7%)  226(38%) 


ROUTINE  ASSESSMENT  (%  ORDERED  FOR  ROUTINE  MONITORING) 
(Pre)  (Post) 

96  (47.3%)  37  (16.3%) 

RESPONSE  TO  02  THERAPY(NON- VENTILATED) 
(Pre)  (Post) 

17(8.3%)  20(8.8%) 

+.03%  cbap2e 
ADMISSION  (INITIAL  VENTILATOR  PARAMETERS) 
(Prt)  (Post) 

20(9.8%)  24  (10.6V.) 

+  .08%  change 
ASSESS  CHANGE  IN  VENTILATOR  PARAMETERS 
(Pre)  (Post) 

48  (23.6%)  107  (47.3%) 

+23.7%  change 
ASSESS  ACUTE  CHANGES 
(Pre)  (Post) 

23(11%)  38(16.3%) 

♦  5.3%  change 

•%  CHANGE  CALCUALTED  (1994-1993  SAMPLES) 

CONCLUSION;    Witb  the  implementation  of  arterial  blood  gas  guldunes,  changes  have  been 
observed  that  suggest  that  the  educational  intervention  has  had  a  direct  impact  on  decrease  us 
of  arterial  blood  gases  for  routines  assessment  After  im  piemen  tattoo  of  guidelines,  this 
technology  b  being  utilised  for  more  appropriate  Indications. 


Medi 


3  a  i  v 


TX. 


Over  the  past  year  the  Hospital  Department  and  the  Program  in 
Respiratory  Care  have  jointly  developed  a  computerized  lung 
station  for  teaching  ventilator  graphics. The  lab  has  been 
utilized  for  simulating  patient  clinical  scenarios  and  to 
develop  training  materials  for  both  students  and  staff.  As  one 
method  of  evaluating  the  lab  we  initiated  a  CPI  process  to 
identify  the  incidence  of  unrecognized  Auto-PEEP  ,  both  before 
and  after  staff  training.  A  data  collection  form  was  created 
which  identified  the  patient  and  ventilator  characteristics  and 
determined  whether  auto-PEEP  was  present  based  on  the 
ventilator  graphics,  and  whether  auto-PEEP  was  recognized  as 
evidenced  by  (a)  the  ventilator  flow  sheet,  (b)  the  physician 
progress  note  or  (c)  the  respiratory  therapist  progress  note . 
The  data  was  collected  by  a  single  investigator  who  evaluated 
all  patients  admitted  to  the  medical/  surgical  services  over  a 
two  week  period.  The  survey  was  then  repeated  following  staff 
development  training  using  the  graphics  analysis  lab.  The 
training  highlighted  recognition  of  auto-PEEP.   Results :   the 
overall  incidence  of  auto-PEEP  was  50%. [47%  (15  of  32  pts)  in 
the  Surgical  units  and  55%  {12  of  22  pts)  in  the  Medical 
units! .   None  of  the  charting  for  the  27  pts  with  auto-PEEP  had 
any  previous  indication  of  its  existence  (100%  unrecognized 
auto-PEEP) .  Auto-PEEP  was  most  frequently  found  to  be  due  to 


ventila 

or  se 

tings,  i.e. 

oo 

low 

a  set  insp 

ry  flowrat 

deceler 

iting 

ing 

arolonged 

catory  tim 

autocyc 

ing  o 

rail  ii 

cidence  of 

PEEP  was 

reduced 

to  18 

(9/50  pts)  . 

All 

of 

s  had  known  as 

or  COPD 

The 

ncidence  of 

llat 

or  induced 

PEEP  was 

to  4% 

(2/50) .  All 

lenc 

PEEP 

ed  and  documented 

lence:  Prior  t 

the  study  the 

only  feedback  we 

hac 

regarding 

the 

effecti 

of  the  lab  w. 

rse/lab  evalua 

ered  by  the  school 

auto-PEEP  is  c 

ne  indicator 

tha 

.tandard 

printed 

als  had  not  been 

y  effective 

form  an 

lysis 
at  lee 

ir:.1 

The 
prov 

ventilato 

st  in  the  she 

d  the 

identif 

catior 

of  auto-PEEP  by 

t  hr* 

staff.  The 

inc 

dence  of 

lly 


ventilator  set ting/ therapist  induced  aut 
decreased.  Our  experience  has  had  severa 

implications :  staff  have  taken  a  much  more  active  role  in 
recognizing,  reporting  and  resolving  inappropriate  waveforms; 
the  frequent  use  of  the  decelerating  flow  patterns  has  been 
reduced,  students  and  staff  enjoy  a  new  sense  of  collegiality 
and  physicians  have  started  to  recognize  the  importance  of 
routinely  evaluating  the  wave  forms. 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1153 


Saturday,  December  2,  12:45-2:40  pm  (Rooms  230C-D) 


A  SIMPLE  MODEL  FOR  TEACHING  THE  VARIABLES  EFFECTING 
FD02  AND  F102  WITH  COMMON  OXYGEN  DELIVERY  DEVICES 

Robert  M.  Keller.  BA.  RRT  and  Jim  Fink,  MS,  RRT 

Hines  VA  Hospital  and  Loyola  Univ.  Chicago,  Stritch  School  of 

Medicine,  Hines  IL. 

Effective  use  of  oxygen  administration  devices  requires  an 
understanding  of  device  limitations  as  well  as  variables  that  affect 
FD02  and  F102.  In  our  institution  we  had  noted  clinicians  with 
unrealistic  expectations  of  oxygen  device  performance  during 
clinical  use.  We  built  a  simple  patient  analog  consisting  of  a  self- 
inflating  resuscitation  bag  without  valve  (FMR,  Puritan)  connected 
via  aerosol  tubing  to  a  mannequin  head  {from  a  Resusci-Annie, 
Laerdal)  with  an  oxygen  analyzer  and  spirometer  in  line. 


02  Analyzer 


Mannequin  Head 


irometer 


The  bag  was  squeezed  to  simulate  patient  respiratory  rate  and  tidal 
volume,  while  oxygen  devices  placed  on  the  head  were  operated  at 
various  oxygen  flow  rates.  In  a  pretest,  a  group  of  30  residents, 
nurses  and  RCPs  consistently  overestimated  FI02  based  on 
references  from  standard  texts.  Upon  completion  of  a  30  minute  lab 
session,  participants  were  able  to  more  accurately  estimate  range  of 
FI02  based  for  each  device,  based  on  liter  flow,  respiratory  rate  and 
tidal  volume  (fxO.001).  We  conclude  that  use  of  this  simple 
laboratory  model  provides  clinicians  with  a  more  realistic 
expectation  for  02  delivery  device  performance  in  the  clinical 
setting. 

0F-95-156 


met) 


EFFECT  OF  MULTI-SKILLED  RESPIRATORY  CARE  PRACTITIONERS  ON  A 
DEPARTMENT  OF  EMERGENCY  MEDICINE.  Rebecca  L.  Meredith.  RRT. 
Nina  M.  Fielden.  MSN.  RN     The  Cleveland  Clinic  Foundation.  Cleveland.  Ohio 
INTRODUCTION:  In  1994,  the  expanded  Emergency  Department  (ED)  at 
faced  with  the  challenge  of  providing  respiratory  therapy  services.  The  new 
located  away  from  the  main  hospital  and  respiratory  therapy  response  times  range  from 
eight  •  12  mm.  The  bed  capacity  is  five  tunes  larger  with  a  projected  doubling  of  patient 
census    One  respiratory  therap>  position  was  approved  in  the  budget  as  an  educator/ 
coordinator  for  the  nursing  staff    Respiratory  Care  Practitioners'  (RCPsJ  have  specialized 
skills  in  regard  to  airway  management  mechanical  ventilation,  and  oilier  modalities  available 
to  optimize  care    Mutti-skilling  and  expanding  me  role  of  me  RCP  to  include  other  patient 
care  relaied  duties  such  as  EKG,  phlebotomy  TV,  central  service  and  orthopedics  were 
explored.  METHODS;  Five  RCPs  that  were  graduales  from  an  AMA  approved  program  for 
respiratory  care  were  hired  into  previously  approved  Patient  Care  Technician  (PCT) 
positions.  These  RCPs  underwent  a  four-week  PCT  orientation  program  that  included  ED 
specific  skills,  The  RCPs  have  assumed  the  technical  roles  of  EKG,  Phlebotomy-TV,  Central 
Service,  and  Orthopedics  along  with  their  respiratory  therapy  skills.  We  further  evaluated  the 
adequacy  of  the  mulu-skilhng  based  on  the  cost  of  personnel  and  orientation,  RCP  job 
satisfaction,  and  physician  and  patient  satisfaction    RESULTS:  Immediate  availability  of  the 
RCP  m  the  ED,  has  moved  respiratory  services  closer  to  the  patient,  eliminating  any 
treatment  delay    Approximately  241)  patients  experiencing  broiuhospasm  are  seen  in  our  ED 
per  month.  Of  these  patients,  130  require  the  delivery  of  three  or  more  beta-agonists  20  mm. 
apart,  oxygen,  rV(s)  and  ABG(s,  with  an  average  treatment  duration  of  60  -  90  nun.  The 
provider  team  of    RN,  RCP,  and  physician  limits  the  number  of  health  care  personnel  that  me 
patient  needs  to  see.  decreasing  patient  stress   The  RCPs  manage  most  of  the  patients'  care 
needs,  allowing  the  RN  to  concentrate  on  other  assignments.  No  additional  orientation  costs 
resulted  due  to  me  multi-skilled  training.  Based  on  volumes  to  date,  we  have  estimated  that, 
as  an  alternative,  5.5  additional  RN  positions  would  be  needed  to  provide  for  the  volume  of 
respiratory  procedures    The  program  has  proven  to  be  less  expensive  from  a  salary 
perspective,  with  an  estimated  annual  savmgs  of  $21 ,000.00  based  on  the  median  salaries  of 
RCPs  and  RNs.  A  RCP  job  satisfaction  survey  was  conducted  after  10  months.  Results  show 
that  RCPs  believe  mat  being  multi-skiUed  has  increased  their  value  to  the  institution  (5/5), 
they  fit  well  into  me  patient  tare  team  and  are  proud  to  be  members  (5/5).  A  survey  of  ED 
attending  physicians  revealed  that  eight  of  10  use  the  RCP  consistently  and  believe  they  are 
an  essential  pan  of  the  patient  care  team.  They  also  believe  the  RCP  has  unproved  patient 
care  efficiencies  (10/10)  and  unproved  the  quality  ot  respiratory  care  (9/10)    A  continuous 
quality  improvement  program  (CQI)  has  been  established  with  preliminary  results  showing  a 
high  standard  of  respiratory  tare  maintained  by  the  RCP.  A  telephone  call-back  with  RCPs 
contacting  pulmonary  patients  discharged  from  the  ED  has  initially  shown  patient  satisfaction 
to  be  very  good   CONCLUSIONS:  Multi-skilling  RCPs  has  improved  our  ED  operation  by: 
1    movmg  the  services  closer  to  the  patient,  eliminating  treatment  delay,  2.  freeing  the  RN  to 
concentrate  on  other  assignments,  3.  decreasing  patient  stress  by  creating  provider  teams, 
4.  savmg  salary  costs  related  to  efficient  use  of  resources,  5    maintaining  a  high  degree  of 
RCP  job  satisfaction,  6    satisfying  ED  physicians,  and  7    maintaining  quality  care. 

OF-95-107 


CALIFORNIA  MANAGEMENT  SURVEY  REPORT  ON  THE  ASSOCIATE  DECREE 
ENTRY  LEVEL  PRACTITIONER  Professional  Advancement  Sub-Committee  -  California 
Society  for  Respiratory  Care,  Tom  Malmowski  BS  RRT  RCP 

Introduction  The  California  Society  for  Respiratory  Care  (CSRC)  Professional  Advancement 
Committee  conducted  a  survey  of  Respiratory /Cardiopulmonary  managers  to  gather  opinions 
on  present  and  future  education/training  requirements  for  RCP's  in  the  state.  The  purpose  of 
the  survey  was  to  validate  the  position  of  the  state  Board  of  Directors  that  the  entry  level 
practitioner  requirements  should  be  elevated  to  the  AS  degree  level.    This  position  was 
consistent  with  the  strategic  educational  direction  identified  by  the  AARC  Consensus 
Conference  on  Respiratory  Care  Education  Methods  505  surveys  were  mailed  to  RC 
department  heads  of  acute  care  hospitals  in  California  Respondents  were  asked  to  indicate 
type  of  facility,  bed  size,  percentage  of  one-year /two- year  graduates,  and  hiring  practices 
within  the  institution    In  addition,  respondents  were  asked  to  indicate  their  opinion  on  7 
questions  related  to  3  categories,  respiratory  care  practice  changes,  departmental  professional 
advancement  practices,  and  entry  level  educational  requirements  within  the  state    Question  U I ) 
The  scope  of  RC  practice  has  expanded  in  the  past  10  years,  03)  The  RCP  is  required  to 
comprehend  and  master  more  information  and  skills  now  than  10  yean  ago.  «3 ) Based  on  the 
scope  of  practice,  the  RCP  of  the  future  will  become  more  independent  and  more  effective  as  a 
consultant  to  other  health  professionals,  *4)  An  AS  in  RC  is  preferred  for  professional 
advancement  within  your  department,  "5)  One  year  technician  programs  should  be  expanded 
to  AS  degree  programs.  *6)  The  AS  degree  should  become  the  minimum  requirement  for  entry 
into  RC  practice  in  the  state,  and  #7)  Two  year  graduales  are  preferred  over  one-year 
graduaies    A  Liken  scale  of  1  to  5  with  1  -  strongly  agree,  2  -  agree.  3  -  no  opinion,  4  - 
disagree.  5  -  strongly  disagree  was  used  for  the  questionnaire.  Statistical  analysis  by  t  test  was 
used  in  comparing  responses  (p<  05)  Results  There  were  272  respondents  for  a  return  rate  of 
54%   242  were  from  acute  care  facilities.  78  which  had  additional  sub-acute  units,  and  82  with 
additional  skilled  nursing  facility  contracts.  6  respondents  were  stand  alone  sub-acute 
departments,  and  6  were  stand  alone  skilled  nursing  facilities.  78%  of  the  respondents  (208) 
were  from  facilities  <300  beds.  Considerably  more  respondents  selected  the  two  positive 
responses  ( I  &2)  than  negative  responses  (4  &  5)  for  all  questions.  This  relationship  was 
tically  significant. 


Question 
irnpondenU 

chooiini  1  *  2 

'  umulilur 


ntf.  rnpon 


222 


212 


*7 

196 


CorcIuiIooi  A  clear  majority  of  surveyed  respiratory  care  managers  in  the  state  of  California 
believe    I )  The  scope  of  practice  and  information  required  for  practice  in  the  state  has 
increased    2)  Thai  graduates  from  two  year  programs  are  preferred  for  hiring  and  promotion 
withui  the  respective  institutions    3)  Two  year  AS  degree  programs  should  be  the  minimum 
entry  level  for  respiratory  care  practice  in  the  stale  of  California. 

OF-95-163 


COGNITIVE  LEVELS  AND  FREQUENCY  OF  DISTRIBl  HON  OF  THE 
LEARNING  OBJECTIVES  IN  THREE  RC  TEXTBOOKS.  David  W.  Chang.  EdD. 
RRT,  Columbus  College.  Columbus.  Georgia 

INTRODUCTION:    Use  of  learning  objectives  (LO)  is  one  of  the  criteria  for  the 
accreditation  of  RC  educational  programs  (JRCRTE  Accreditation  Essential  V.  Self- 
Study  Appendix  H)  Since  many  RC  textbooks  include  LO  and  no  studies  have  been 
done  on  the  LO  of  these  textbooks,  I  evaluated  the  cognitive  levels  and  frequency  of 
distribution  of  these  LO  in  three  RC  textbooks.    METHOD:  Three  current  editions  of 
multi-author  RC  textbooks  with  written  LO  were  chosen  and  the  abbreviated  titles 
(year  published)  were  Mechanical  Ventilation  (1992),  Comprehensive  RC  (1995),  and 
RC  Equipment  (1995).  From  each  textbook,  the  first,  middle,  and  last  chapters  were 
used.  The  behavioral  terms  of  the  LO  at  the  beginning  of  each  chapter  were  classified 
and  grouped  inlo  one  of  six  cognitive  levels  using  the  criteria  described  by  Bloom  ct  al 
(1956).  These  six  levels,  from  low  to  high  cognitive  measure,  are  listed  below  with 
examples  of  the  respective  behavioral  terms;  (1)  Knowledge  (define,  describe,  list);  (2) 
Comprehension  (discuss,  explain,  interpret),  (3)  Application  (assemble,  calculate, 
perform);  (4)  Analysis  (compare,  diagnose,  distinguish),  (5)  Synthesis  (create,  develop, 
predict);  (6)  Evaluation  (certify,  judge,  prove)  The  behavioral  terms  were  interpreted 
m  the  context  of  the  entire  sentence  in  Ihe  LO  since  some  behavioral  terms  could  be 
placed  in  two  or  more  cognitive  levels  The  cognitive  levels  and  frequency  of 
distribution  of  these  LO  were  recorded  for  all  nine  chapters.  For  this  descriptive  study, 
frequency  count  and  percentage  calculation  were  the  only  statistical  tests  done. 
RESULTS:   The  cognitive  levels  and  frequency  of  distribution  of  the  LO  in  this  study 
arc  listed  below  by  frequency  counts: 


Cognitive  Levels 

Mcch  Vent 

Come  RC 

L  RC  Equip 

Knowledge 

32   (73%) 

24    (86%) 

35   (60%) 

Comprehension 

9   (20%) 

1    (4%) 

12   (21%) 

Application 

1    (2%) 

i  U%) 

5   (9%) 

Analysis 

0   (0%) 

2    (7%) 

6    (10%) 

Synthesis 

2   (5%) 

0   (0%) 

0   (0%) 

Evaluation 

0   (WTO 

0  (0%) 

0    (0%) 

Total  #  (%)  of  Lt) 

44    (100%) 

28    (100%) 

58  (100%.) 

CONCLUSIONS:    Majority  ol  ihe  LO  in  these  three  RC  textbooks  were  written  al  the 

Knowledge  and  Comprehension  levels  ('IV;  .  W id  SI';,  ie-.pe.lneh)    1  Ins 

distribution  differs  from  Ihe  NBRC  Examination  Matrices  in  which  only  :"' .   (CRl'I  ) 
and  21%  (written  RRT)  of  Ihe  exam  items  were  written  below  Ihe  Application  level 
(NBRC,  1994).  Extensive  use  of  LO  written  al  lower  cognitive  levels  may  discourage 
students  from  using  their  critical  thinking  skills  To  enhance  the  learning  outcome,  the 
LO  in  the  textbooks  should  be  reviewed  and  revised  bv  the  i 
the  educational  goals  ol  a  RC  course. 


1  154 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


Saturday,  December  2.  12:45-2:40  pm  (Rooms  230C-D) 


COMPARISON  ON  THE  USE  OF  THE  MODIFIED  NEDELSKVS 
PROCEDURE  PERFORMED  BY  RC  EDUCATORS  AND 
PRACTITIONERS  David  W.  Chang.  EdD.  RRT.  Columbus  College, 
Columbus.  Georgia,  Sandra  Gaviola,  RRT,  Greater  Johnstown  Career  and 
Technology  Center,  Johnstown,  Pennsylvania. 

INTRODUCTION:  The  modified  Nedelsky  procedure  is  commonly  used 
to  calculate  the  minimal  passing  indices  (MPI)  of  questions  in  a  multiple- 
choice  exam.  Since  the  procedure  specifies  use  of  a  small  group  (less  than 
8)  of  subject  matter  experts  but  not  the  professional  experience  and 
background  of  these  experts,  we  compared  the  use  of  the  modified 
Nedelsky  procedure  by  teaching  RC  educators  (RCE)  and  non-teaching  RC 
practitioners  (RCP).  We  sought  to  determine  whether  the  MPI  and 
subsequently  the  cut  score  of  an  exam  can  be  done  by  RCE  alone. 
METHOD:  Thirty  current  NBRC  written  RRT  self-assessment  questions 
were  selected  at  random  with  10  questions  in  each  cognitive  levels  -  recall, 
application,  and  analysis.  Five  RCE  and  six  RCP  (all  RRT's)  used  the 
modified  Nedelsky's  procedure  and  evaluated  all  150  responses  in  these  30 
questions.  Each  response  was  scored  between  0  and  2  points  by  consensus 
(3  or  more  RCE  in  agreement  OR  4  or  more  RCP  in  agreement).  Point 
assignments  were  done  by  consensus  as  follows:  correct  response  (2 
points),  incorrect  but  plausible  response  (1  point),  incorrect  response  (0 
points).  The  MPI  for  each  question  was  calculated  by  dividing  the  correct 
response  (2  points)  by  the  total  possible  points  (ranges  from  2  to  6  points). 
I-test  was  used  to  evaluate  the  difference  of  the  MPI  determined  by  RCE 
and  RCP.  RESULTS:  The  MPI  of  the  30  questions  determined  by  RCE 
ranged  from  0.33  to  1.0  (mean  =  0.66,  S.D.  =  0.18)  and  that  determined 
by  RCP  ranged  from  0.4  to  1.0  (mean  =  0.67,  S.D.  =  0.15).  The 
calculated  1  was  0.214  and  the  table  I  ■«  was  2.002.  CONCLUSIONS: 
There  was  no  significant  difference  between  the  MPI  determined  by  RCE 
or  RCP.  The  subject  matter  experts  specified  by  the  modified  Nedelsky 
procedure  may  consist  of  RCE.  RCP  or  a  combination  of  these  two  groups 
of  experts.  This  study  indicates  that  the  MPI  and  cut  score  of  an  exam 
may  be  determined  by  RCE  only  without  adding  RCP  to  the  panel  of 
experts. 


•Save Time  »*  fewer  repairs 

•Save  Money  ■*  less  labor 

•  Save  \bur  Equipment  •'*  no  contamination 

•Save  Expense  ■*  less  stand-by  equipment  needed 

High 

Pressure 

Line 

Filters 

T 

Stop  Particulates 

Stop  Moisture 

Protect  your  ventilators,  blenders,  and  anesthesia  machines 
from  compressor  water,  dirt,  calcium,  and  other  contamination. 
Our  HPL  filters  will  retain  O.lum  particles  and  stop  water.  They 
can  replace  water  traps  and  particulate  barriers.  The  built-in 
drain  allows  easy  draining,  and  we  will  guarantee  them  for  a 
year.  This  product  is  inexpensive  insurance  for  you! 

-       .  _  _        „  .401  West  Morgan  Road 

Arbor  ItlBuiCBl  Ann  Mmi-  m  mos -9i°9 

Arbor  Technologies,  Inc.    Phone  (313)663-6662 

a  Fax  (313)  665-3516 


Circle  141  on  reader  service  card 


EVERYONE'S  CONCERN! 

MEDICAL  COSTS  •  MEDICAL  WASTE  •  PERSONNEL  SAFETY 

Think  Globally,  Act  Locally 
Think  Pasteurization,  Think  HR 

Choose  the  Best'  AerOSOl 

Sten-Vers  Efficient!  insukted!  Treatment 

Washer  Plus        warm  inside  -  Cool  Outside  Guard 

Aerotherm  Dryer 


The  Steri-Vers  System 
and  Washer  Plus  wash 
and  pasteurize  better 
with  agitation! 
NO  DRIP! 
NO  FUSS! 
NO  MUSCLE! 


Reduce  exposure 
to  TB.  Safety  and 
peace  of  mind  with 
theATG! 


HR  Incorporated 

P.O.  Box  1744  •  Bellevue,  WA  98009  •  (800)  426-1042  •  Fax  (206)  881-3654 


Circle  139  on  reader  service  card        Visit  AARC  Booths  1500  and  1501  in  Orlando 


ll  55 


Saturday,  December  2,  3:00-4:55  pm  {Rooms  230A-B) 


TRADITIONAI  VLRXUS  NoN-TRADl"!  K  >NAI  Ml  THODSOF  SHORT  TERM  POSITIVE 

PRP.SSURI     VINIIIAMON  A  COMPARISON  STUDY 

Wendy  1.   laChauncc.RRT 

Joan  Blondtn,  DS,  RRT 

Fletcher  Allen  Health  Cure.  MCHV  Campus 

1 1  I  Colchester  Avenue 

Burlington.  Vermont  05401 

In  an  effort  lo  address  the  continued  shortage  of  intensive  care  unit  beds  and  10  improve  the  quality  of 
care  for  our  patients,  we  formed  a  team  of  professionals  to  compare  the  effectiveness  of  noninvasive 
positive  pressure  ventilation  (N-11'PV),  lo  invasive  intuhaiion  and  conventional  mechanical 
ventilation  The  comparison  study  included  36  patients  who  were  diagnosed  with  progressive 
rcspiroiorv  failure  Of  the  1(»  patients,  the  pnmarv  causes  of  respiratory  failure  included  acute 
pulmonary  edema (nel  I),  COPD  (n=10),  post-op extubatjoo  respiratory  failure  (N=8).  limited 
support,  DNR  (N=4l,  neuromuscular  disease  (N=2)  and  chest  trauma  |N=1 )  A  physician  makes  the 
decision  to  institute  N-IPPV  based  on  pre-established  criteria  RR>3n.  Pll<7  30  with  PC02  >55,  and 
Pa02  <55  or  02  sat<9(i  (dial  does  not  res-pond  to  supplemental  02)    A  respiratory  practitioner  then 
initiates  N-IPPV  and  adjusts  die  sellings  according  lo  a  therapist  driven  protocol   Hie  results  lodatc 
arc  verv  encouraging  Of  the  36  patients  studied.  75%  (N"27)  improved  and  did  not  require 
intubation.  14%  (N~5>  worsened  and  required  intubation,  and  1 1%  (N=4)  died  (per  advance 
directives,  DNR)    1  he  most  favorable  response  to  N-IPPV  was  noted  in  the  acute  pulmonary  edema 
(91%  improved  without  intubation)  and  COPD  (80%  improved  without  intubation)  groups 
Throughout  the  study,  no  significant  complications  were  noled,  and  no  additional  staffing  was 
required  to  institute  treatment   I  ising  historical  patient  dala  from  a  six  month  prc-pro|ecl  penod,  we 
estimated  the  average  length  of  intubation  and  mechanical  ventilation,  of  patients  with  similar 
diagnosis  and  degree  of  respiratory  failure,  lobe  approximately  4  days  We  compared  this  to  an 
average  length  of  N-lPPVof  2  davs  Since  N-IPPV  is  non-invasive,  patients  did  not  always  require  an 
ICt  I  bed  Seven  of  our  36  study  patients  were  managed  on  the  general  wards,  and  24  required  an  ICU 
bed  The  two  da\  drop  in  ICU  stay  translates  into  a  dollar  savings  of  $156,015  in  six  months  Other 
benefits  realized  include  increased  patient  and  employee  satisfaction  as  evidenced  by  interviews  and 
patient  satisfaction  surveys  and  a  reduction  in  the  risk  factors  associated  with  intubation  and 
conventional  ventilation  In  conclusion,  we  feci  that  N-IPPV  is  a  safe  and  effective  alternative  to 
intubation  and  mechanical  ventilation  in  some  patient  populations  N-IPPV  can  eliminate  the  need  for 
intubation  and  reduce  the  length  of  stay  in  the  [CI  I  thereby  conserving  valuable  and  expensive 
resources  and  reducing  the  cost  of  care  to  the  patients  and  the  i 


LULu 


Haft/ord  Haipiu 

INTRO     Btleve 

chroruc  bypoven 
defeca     Howev 

tracheostomy  tut 
METHODS     Pi 


R.PAPtrach     A  NOVEL  FORM  OF  AUGMENTING  VENTILATION 

,  S  Iumgictn.RN    K  rhrmnpher.  MP ..  D  Onprtlo.  M.D..  RejpiraiDry  Care  DepMtniM 


-uRiPAPthachi  io  provide  ■ 


y  preuurc  (BiPAP)  has  been  mat  u  ■ 

■  in  high  inspiratory  pressures  in  onlcr 
of a  Respiritroiuc*  BiPAP  device  deb. 


li'1-.tu.  'r'.i 


Additionally 


adequate  ventilation. 


d  candidates  for  i  trial  o 


1 1  turn  dunng  the  day     PlUenU  ei 


y  hypertension,  wd  puenu  intoler 


IIM'ISGS    HiPAf>nt*f-H  dr hvriBri 


nic  hypo  ventilation  iyr 
■d  reduction  in  divttme 
:nt  side  effect     BiPAPtbach  til  own  continuous  phonation 
u  ventilatory  support.    BiPAPrtAra 


EFFECTS  OF  VOLUME  CONTROL  <VC)  VERSUS  PRESSURE  VENTILATION  ON 
PATIENTS  WITH  HYPOXEMIC  RESPIRATORY  FAILURE  Jamie  Vaccaro.  RRT.  John 
Slcinbach.  BS.  Mark  Lund.  BS.  Amy  Orons  BA.  Don  Miller,  the  Respiratory  Care  Staff. 
Herbert  Patrick.  MD.  Department  of  Respiratory  Care,  Thomas  Jefferson  University  Hospital. 
Philadelphia.  PA 


Introduction  At  our  institution  patients  meeting  criteria  for  hypoxemic  respiratory  failure,  a 
FI02  >  60%  or  a  Pa02/F102  <  120.  were  eligible  for  a  study  examining  the  effects  of  VC  vs 
pressure  ventilation  on  pulmonary  mechanics,  oxygenation,  ventilation,  and  cardiac 
parameters  using  the  Bear  1000  yentilator  (Allied  Healthcare,  inc    Riverside,  CA)  The 
modes  of  pressure  yentilation  were  Pressure  Augment  (PA)  Maximum  (PAM)  without  and 
with  inspirator,  pause  (IP)  PA  provides  pressure  support  breaths  with  a  brcalh-bv -breath 
minimum  Vt  guarantee  PAM  is  the  PA  sufficient  to  insure  the  Vt  without  evoking  the 
guarantee  We  hypothesized  that  PAM  +  IP  would  mimic  pressure  control  yentilation  without 
being  labor  intensive  Methods  Each  patient  was  initially  ventilated  in  VC  using  decelerating 
flow  for  4-6  hours  and  then  was  switched  to  PAM  with  idenucal  RR.  Vt,  F102,  and  PEEP 
setungs  If  the  FI02  remained  >  60%.  IP  was  added  until  cither  auio-PEEP  was  detected  or 
the  I  E  rauo  =1  I.  the  RR,  Vt.  F102,  and  PEEP  settings  wen  again  retained  for  another  4-6 
hour  interval  Data  were  anab/.cd  in  pairs  corrected  for  the  duration  of  VC  VI  PAM  and  Pre- 
(PAM  +  IP)  vs  PAM  *  IP  Results  We  prospectively  studied  21  patients  from  November 
1994  to  April  1993  Data  shown  are  mean  +  SEM  with  p  <  0  05  ANOVA,  *VC  VS  PAM  and 
•Pre  {PAM*  IP)  vs  PAM*  IP 


Mode  v  6  hours 

VC 

PAM 

n 

21 

21 

Pa02/FI02 

850  +  50 

97  9  +  6  4 

PIP 

•17  1  +  1  6 

43  4  +  24 

MAP 

180+  1  4 

16  7+  98 

PrFR  actual 

95  I  +  2  5 

97  3+4  7 

Vl  actual 

755  +  23 

863+25* 

Vc  actual 

15  3+82 

16  1  ♦  86 

IE 

136+  25 

135+   21 

CVQt 

0  39  ♦   03 

0  39  +  03 

Vd/Vt 

0  65  ♦    20 

0  66  +  02 

CO 

76+58 

74+48 

PrclPAM  +  lPl 

PAM  t  IP 

16 

id 

8111  +  52 

94  8  +  9  1 

46  5  +  2  3 

45  7  +  2  1 

16  8  +  83 

20  8  +  1  1 ♦ 

106  0  •  5  ii 

103  8  +  40 

826  •  24 

869  t  32       ' 

13  9+   70 

15  3+  69 

1  35  +   22 

126+  20  + 

I  ' 4 

(1  15  •    H4 

0  64  ♦   03 

1160+  115 

82+78 

79+62 

Sixteen  patients  (76%)  required  PAM  +  IP  as  the  FI02  remained  •  60%;  there  yvcrc  clinical 
delays  from  the  end  of  PAM  to  the  initiation  of  PAM  *  IP  ranging  from  o  5  lo  2  16  hours 
(aycragc  27  hours)  auto-PEEP  was  not  delected  in  am  mode  Conclusion  Both  PAM  vs  VC 
and  PAM  *  IP  VI  pre  (PAM  ♦  IP)  appear  to  improyc  oxygenation  without  compromising 
cardiac  parameters  PAM  *  IP  are  alternatives  to  VC  in  patients  with  hypoxemic  respiratory 
failure  the  prevent c  of  a  hrc.uh-b\ -breath  Vt  guarantee  should  entourage  PAM  usage 


PRESSURE  CONTROLLED  INVERSE  RATIO  VENTILATION  (PC-IRV)  IS  IMEFFECTIVE 
EARLY  1>I  ADULT  RESPIRATORY  DISTRESS  SYNDROME  (ARDS)  INDUCED  BY  OLEIC 
ACID  Timothy  B  Op't  Holt  Ed  P..  R.R.T..  University  of  South  Alabama.  Mobile,  AL  and  Tom 
Clanlon.  Ph  D.  The  Ohio  State  University,  Columbus,  OH 

INTRODUCTION  Since  ARDS  was  first  described  in  1967,  mortality  has  been  high.  50%  or 
greater,  depending  on  the  study  reviewed  and  the  etiology  of  the  symptoms  Volume  ventilation  with 
PEEP  is  a  mainstay  of  support,  which  may  lead  to  barotrauma  It  is  suggested  that  practiUoners 
reduce  peak  airway  pressure  during  ventilation,  substituting  instead  pressure  controlled  inverse  ratio 
ventilation  (PC-IRV)  to  support  oxygenation  and  ventilation  without  the  hazard  of  barotrauma  We 
examined  the  effects  of  PCIR  V  on  extravascular  lung  water  (EVLW),  pulmonary  mechanics, 
hemodynamics,  and  gas  exchange  We  hypothesized  that  prophylactic  or  early  treatment  of  ARDS 
with  PC-IRVwould  result  in  a  significant  reduction  in  lung  injury  (as  measured  by  changes  in  EVLW 
and  compliance)  and  improvement  in  gas  exchange  (as  measured  by  shunt  and  P(  A-ajO,  i 
MATERIALS  AND  METHODS  Hourly  measurements  were  obtained  in  two  groups  of 
anesthetized  dogs  wherein  ARDS  yvas  induced  by  Oleic  acid,  0  1  SmlA.g  The  control  group  (n=6) 
received  assist/control  ventilation  to  maintain  blood  gases  within  normal  limits  FiO,  was  adjusted  to 
keep  PaOi  >60  mm  Hg  PC-IRV  at  an  IE  ratio  of  2  I  was  instituted  in  the  experimental  group  (n=8) 
in  the  control  mode    Inspiratory  pressure  was  set  to  deliver  a  tidal  volume  of  1 5  ml/kg.  allowing 
mean  airway  pressure  to  vary    PEEP  remained  at  5  cmHjO    Carbon  dioxide  retention  was  treated  by 
increasing  the  ventilatory  rate  Intrinsic  PEEP  was  not  measured  systematically  When  it  was 
measured,  it  was  1  -2  cm  H,0  Dopamine  was  administered  to  keep  mean  BP  >80  mm  Hg 
RESULTS  See  table  Fluid  administration  was  higher  inthe  PC-IRV  group  in  an  attempt  to  increase 
the  wedge  pressure  to  >  1 2  mm  Hg  pnor  to  PC-IRV,  maintain  mean  arterial  BP  >  80  mm  Hg.  and  to 
deliver  dopamine  There  were  no  significant  differences  (using  unpaired  t-tesls)  in  other  parameters 
(0^,.  PIP.  P(A-a)0„  P/F.  Qs/Qt.  PaCO/Vc)  between  the  two  groups  at  hour  seven 
CONCLUSIONS  In  this  dog  model  of  ARDS,  there  was  no  apparent  benefit  from  PC-IRV,  early  in 
ARDS  before  static  compliance  fell  to  20  mL/cm  H,0  Even  with  a  significantly  greater  fluid  intake 
in  the  PC-IRV  group,  EVLW  was  not  significantly  greater  than  thai  in  the  A/C  group  PC-IRV  and 
the  concurrent  increase  in  mean  Paw  had  detrimental  effects  on  Qt  and  arterial  BP,  requiring 
inordinate  amounts  of  dopamine  and  fluid    This  study  was  limited  by  a  non-constant  mean  Paw. 
which  could  have  been  accomplished  if  tidal  volume  were  decreased,  recently  suggested  PC-IRV 
did  not  as  we  had  hoped,  improve  oxygenation  (as  others  haye  found  in  more  advanced  lung 
disease)  or  decrease  EVLW  There  was  no  relationship  between  the  gain  in  body  water  and  the 
gain  in  EVLW  Based  on  these  data.  PC-IRV  was  not  beneficial  early  in  the  course  of  ARDS 

Results 


iHg 


n  Hg     L/min 


jH,0 


DO,  EVLW  IVfluid 

mlOj/min        gll.O/Kg       L 


A/C  189+14    4  0+18    3  5+06   116+2  0 

PC-IRV  26  1+4  7   9.3+3  3    18+0  5  17  9+4  2 

p-  005  007         0001        006 

This  research  partially  fundcii  hv  Ihe  Hrcmcr  Inundation 


I  I  5C 


Respiratory  Cari-  •  Novi:mbhr  '95  Vol  40  No  1 


Saturday,  December  2,  3:00-4:55  pm  (Rooms  230A-B) 


HIGH-FREQUENCY  OSCILLATORY  VENTILATION  IN  PEDIATRICS; 
A  REVIEW  OF  APPLICATION  AND  MANAGEMENT  PRACTICE 

Lauren  Pcrlman  RRT.  Peter  BcUl  RRT.  John  H  Arnold  MD 

Departments  of  Respiratory  Care  and  Anesthesia. 

Children  's  Hospital  and  Harvard  Medical  School, 

Boston  MA 

The  application  of  high-frequency  oscillatory  ventilation  (HFOV)  in  pediatric  patients  has 
recently  increased  Published  data  with  respect  to  HFOV  settings  and  management  are 
limited  in  this  population  We  reviewed  the  use  of  HFOV  (SensorMedics  3 100/3 10OA.  Yorba 
Linda,  CA)  in  our  pediatric  ICU  in  order  to  identity  trends  in  management  strategies  HFOV 
data  was  retrospectively  reviewed  from  1/1/94  to  5/1/95  Data  included  age.  diagnosis  (EH), 
weight,  frequency  (FREQ).  maximum  power  setting  (MPS)  with  corresponding  PaCO; ,  and 
F\s  at  one  and  24  Hrs  with  corresponding  F-'  ().  and  P-jO-  The  P«»  requirement  on 
conventional  ventilation  (CV)  was  compared  to  the  one  Hi  HFOV  P^  Forty-four  patients, 
ages  two  months  to  28  years,  were  evaluated  Five  were  excluded  from  the  24  Hr  data  (3 
expired  1  placed  on  ECMO  and  1  HFOV  was  discontinued!  Groups  by  Dx  were: 
ARDS(n»19),  infectious  pneumonia(n=14).  RSV(n-6)  and  other(n=5)  Four  weight  groups 
were  established  A:2  5-10kg.  B  1  l-20kg,  C  2 1-tOkg  and  D:41-60kg 

Results  fmeaniSDj 

AC  5-IOkg) 

B(ll-20Kg) 

rci2i-uike> 

D(4l-60Kg) 

Frequence  (hz) 

12*2.2 

8*09 

7*1  2 

6*07 

MPS 

4  95*1  78 

6  02*1  48 

5  95*2  23 

701*1  2 

PaCO;  (mmHg) 

52*15 

45*132 

50*13  9 

58*11  8 

Part  1  Hour  (cmH.O) 

26±38 

30*4  5 

25*5  1 

30*3  9 

F.02  1  Hour 

9I±12 

99*5  3 

93*14.1 

100*0,0 

PaOj  1  Hour  (mmHg) 

117*75  8 

103*546 

157*84  6 

161*88  4 

P„  24  Hours  (cmH-O) 

24±39 

26*5  5 

22*44 

26*3  6 

FA  24  Hours 

6U29 

59*8  2 

63*65 

58*68 

PaO;  24  Hours  (mmHg) 

85±31 

86*33  3 

91*33  4 

85*22  6 

FREQ  was  decreased  in  the  higher  weight  groups  with  a  significant  difference  between 
{roups  A  and  C.  and  groups  A  and  D  (p<0  00 1 )  FREQ  adjustments  were  made  in  2/44 
Kbents  The  MPS  used  in  group  D  was  significantly  higher  than  in  group  A  (p<0  05)  There 
was  no  significant  difference  in  PaCO;  between  groups  The  mean  P„  on  CV  was  19  8±3  6 
and  at  one  Hr  on  HFOV  wns  27  6±4  8  overall  The  mean  F.O;  decreased  from  95±  10  2  at  oni 
Hr  lo  60*6  3  at  24  Hrs  for  the  entire  series  of  patients  We  conclude  that  1 )  lower  frequende 
are  used  to  ventilate  larger  patients.  2)  venulation  is  preferentially  managed  by  adjusting  the 
power  control  over  FREQ.  3)  initiation  of  HFOV  with  a  P„  7.2±4  3  >CVP„  permits 
subsequent  reduction  in  F.O;  to  .60  by  24  Hrs.  Whether  a  strategy  utilizing  a  higher  FREQ 
with  the  remaining  available  power  would  be  more  beneficial  is  an  area  for  future 
invest!  ganon 

OF-95-11 

2 

IMPROVED   OXYGENATION   IN    RDS  WITH   EARLY   HFOV  COM- 
PARED   TO  CV:   THE   PROVO   MULTICENTER  CONTROLLED 
CLINICAL  TRIAL.  Dale  Gerstmann  MD,  Stephen  Minton  MD,  Ronald 
Stoddard  MD,  and  Gordon  Lassen  RRT.  Ulah  Valley  Reg  Med  Cen, 
Provo,  UT;  Keith  Meredith  MD  and  Frank  Monaco  RRT,  Memorial  Hos- 
pital, Colorado  Springs,  CO,  Jean  Marie  Bert/and  MD,  O  Battisti  MD.  JP 
Langhendnes  MD  and  A  Francois,  Clinique  Saint  Vincent,  Rocourt,  Bel- 
gium Introduction:  We  evaluated  the  oxygenation  and  ventilation  re- 
sponse in  preterm  infants  <35wks  GA  with  RDS  who  required  ventilator 
support,  received  exogenous  surfactant,  and  were  randomly  assigned 
to  either  HFOV  or  CV.  Method:  In  a  multicenter  randomized  controlled 
clinical  trial  without  crossover  64  neonates  were  assigned  to  HFOV  and 
61  to  CV  HFOV  was  used  with  a  strategy  to  promote  early  rapid  lung 
recruitment  Repeat  surfactant  doses  were  given  for  Pa/AO2<0.50  All 
blood  gas  values  during  the  1st  7d  of  life  were  collected  along  with  ven- 
tilator settings  at  the  time  of  blood  gas  draw  (n=4512)  Each  patient's 
blood  gas  values  were  averaged  within  the  following  intervals:  -4  to  Oh, 
0-2h,  4±2h  intervals  to  24h,  8±3h  intervals  to  48h,  12±4h  intervals  to  7d 
All  averaged  patient  values  were  then  pooled  for  HFOV  and  CV  grp 
analysis  using  ANOVA  (Repeated  Measures)  Results:  Birth  weight 
and  estimated  GA  were  1.56±0.46  vs  1.46±0.47  kg,  and  30  8±2.2  vs 
30,1  ±2.7  wk  for  HFOV  and  CV  grps  respectively.  Age  at  study  start  was 
2-3h  of  life  Paw  was  significantly  higher  over  the  1  st  wk  of  life  for  the 
HFOV  grp,  p<0.0001 .  HFOV  F1O2  levels  were  weaned  to  O  30  by  8h, 
with  Fi02  at  all  timepoints  up  to  48h  lower  than  with  CV,  p<0.05  each. 
Pa/A02  rapidly  increased  with  HFOV  to  >0.50  by  4h  into  the  study,  with 
values  in  intervals  between  4-36h  exceeding  those  for  CV,  p<0  05  each. 
F1O2  and  Pa/A02  were  significantly  improved  with  HFOV  compared  to 
CV  over  the  first  week  (p<0  00001 ,  each)  PCO2  values  were  the  same 
between  grps  over  the  1st  7d  of  the  study.  The  number  of  HFOV  pa- 
tients receiving  >1dose  surfactant  was  less,  16%  vs  46%,  p<0  0004 
Conclusions:  Using  HFOV  early  in  the  course  of  RDS  with  a  treatment 
strategy  objective  to  reverse  atelectesis  and  improve  lung  volume 
through  the  use  of  Paw,  we  were  able  to  significantly  improve  oxygen- 
ation but  yet  decrease  the  frequency  of  subsequent  surfactant  dosing. 
(Partial  funding  for  data  review  was  provided  by  grants  from  Ross  Labo- 
ratories and  SensorMedics  Critical  Care.) 

OF-95-228 


ADULT  HIGH  FREQUENCY  IN  ARDS)  A  REVIEW  OF  TWO  CASES: 
N.Tate  Bennett.  RRT.  Cape  Fear  Valley  Medical  Center, 
Fayetteville,    N.C.: 

High  Fl0,    and   increased  ventilating  pressures    are   problems 
commonly   associated  with   the   care    of    ARDS   patients.    Clinical 
trials    suggest    that    the  use  of   High  Frequency  Ventilation    (UHFV) 
may  be   beneficial.    We    examine    two  patients    in  ARDS    ventilated 
with   the    Infraeonics    Star    1010   High  Frequency  Ventilator    after 
failing   conventional   mechanical   ventilation. 

A  31  year   old    female  was    admitted    to    the    hospital   with 
pelvic   pain.    She  was   diagnosed  with  pelvic    inf lajranatory 
disease,    sepsis,    and  ARDS.    With  an   F, ,    of    1 . 0    abg ' a    revealed 
a    P.,;    of    59   mmHg.    After    intubation   and  ventilation  on 
pressure   control   ventilation   and    F,      of    1.0    her    l\  .   was    80 
mmHg   after    24    hours.    Peak  Airway    Pressure    (PAP)    was    35 
cmH20,    Mean  Airway  Pressure    (HAP)       21    cmH20,    and   PEEP    10 
cmH20   on  conventional   ventilation  at    the    time   of    the    switch 
to  UHFV.    For    the   24    hours   prior    to   UHFV   PAP  was    34   ±   6 
CS1H20,    MAP    20    i    3    cmH20,     and    PEEP    9    +    1    cmH20.    She   was 
placed  on    the    Star    1010    and    1    hour    later    P. .    was    162   mmHg. 
Fl0]   was    decreased   steadily   and   24    hours    after    implementation 
of   UHFV  her    P.0]  was    121   mmHg  with  an   P10]    of    .30.    PAP  was    35 
cmH20,    MAP    19    cmH20,    and  PEEP   7    cmH20   upon    implementation   of 
UHFV.    Mean    PAP   was    33    ±    5,    MAP    20    ±    3    cmH20,    and    PEEP    9    ±    1 
for    the    24    hours   after   UHFV.    Five   days    after    the 
implementation   of    UHFV   the   patient  was    extubated. 

A   22    year    old   male   preeented   with   multiple    rib    fractures 
with    flail    chest,    bilateral   pneumothoraces,    and  pulmonary 
contusion.    After    intubation   and  conventional  mechanical 
ventilation  with  an  F,0,  of   1.0   his   P40,  was  75  mmHg.    PAP  was 
38    cmH20,    MAP    23    cmH20,    and    PEEP    15    cmH20.    For    the   period    of 


time    preceding    UHFV    met 

wa 

31 

±    3    cmH2  0, 

HAP    20 

t    3 

cmH20,    and   peep   10  ±  1 

cmH2 

.    He   de 

■atura 

:ed  a 

:utely  w 

ith 

accompanying  bradycard: 

a.    He   wa 

■    Pi 

»ced   o 

i   the 

Star    1010    and 

ABO   1    hour    later    revea 

ed   a 

P,0, 

Of 

78    mmHg    with    an    F10 

of 

1.0.    After    Implementat 

on  o 

UHFV    i 

litial 

PAP 

vae    3  8    cmH20, 

HAP    24    emH20,     and    PEEP 

10    ci 

iH20 

Fo 

r    the 

24    hours    foil 

awing 

implementation    of    UHFV 

mean 

PAP 

was 

32    ± 

1,    cml 

12  0,     HAP 

21   ± 

2    cmH20,    and   PEEP    10    ± 

4    cmH2  0. 

His 

condi 

Lion 

stabiliz 

■d  and 

24    hours    after   UHFV   hli 

P.OJ 

was 

107 

mmHg 

/ith 

n  F101  oi 

.50. 

He   continued    to    improvt 

and 

was 

extubated 

nine 

days    af 

tar 

admission    to    the    hoapi 

al. 

These  patients   appei 

r  to 

have   be 

raefitt 

■d  fr 

am  UHFV, 

but 

controlled   studies    are 

needed. 

OF-95-019 

CARDIAC    STATUS    IN    A    GROUP    OF    LONG    TERM    VENTILATED    PER- 
SONS   SUFFERING    FROM    DUCHENNES    MUSCULAR    DYSTR0PHY( DMD) . 
Ole    Narregaard    &    Bent    Juhl.     Danish    Respiratory    Center 
West,    Arhus    University    Hospital,    Arhus,    Denmark. 
Cardiac    status    (CS)    has    gained    increasing    importance 
as    a    predictor    of    survival    in    DMD-patients    as    the    na- 
tural   cause    of    death    from    respiratory    failure    has    been 
overcome    by    long    term   mechanical    ventilation.    The    aim 
of    this    paper    is    to    report    CS    in    a    group    of    20    DMD- 
patients,    aged    24.6   +/-    5.3    years    (mean    +/-SD)    who 
have    been    ventilated      for    3.3    +/-    1.4    years . Eighteen 
via    an    uncuffed    tracheostomy    tube    20.9    +/-    5.B    hours 
per    day    and    2    using    the    BiPAP    ( Respironics )    nine    hours 
per    day.    Echocardiography    was    normal    in    12    persons,    1 
showed    a    thin    wall    of    the    left    ventricle,    2    slightly 
to    moderately    dilated    right    ventricle,    1    universal 
hypokinesia    with   ejection    fraction    of    10-20    %    (died), 
1    abnormal    septal    motion,    1    dilated    and    hypokinetic 
left    ventricle,     1    slight    global    hypocon  trac  t  Hit  y   and 
1    prolapse    of    posterior    mitral    valve.    ECG    was    normal 
In    9    persons,    right    bundle    branch    block    was    found    in 
6    persons,    QTT    TTT    v,    ,    in    4,    right    hypertrophy   in    4 
and    ST-deprelsion    inVperson.    Conclusion:    several 
years    after    death    probably    would    have    occurred    from 
respiratory    failure,    60X    of    these    DMD-patients    showed 
no    signs    of    cardiac    disease    as    measured    by    echocardio- 
graphy   and    only    10X    presented    severe    changes.    Forty- 
five    presented    a    normal    ECG. 


Respiratory  Care  •  November  '95  Vol  40  No  1 


157 


Saturday.  December  2,  3:00-4:55  pm  (Rooms  230A-B) 


NASAL  ASSIST  CONTROL  VENTILATION  IN  THE  POSTOPERATIVE 
CARE  OF  CHILDREN  WITH  CONGENITAL  HEART  DISEASE 
Douolas  E.  Petsinger,  B.S..  R.R.T.  and  Angel  R.  Cuadrado,  MD. 
Egleslon  Children's  Hospital  at  the  Emory  University,  Atlanta,  Georgia 
INTRODUCTION:  Tracheal  intubation  and  mechanical  ventilatory 
support  are  routine  in  the  postoperative  care  of  children  recovering  from 
surgical  repair  of  congenital  heart  disease.  Nasal  Assist  Control 
Ventilation  (NACV)  can  be  a  novel  bridge  from  mechanical  ventilatory 
support  to  supplemental  oxygen  therapy  in  their  postoperative  period. 
METHOD:  A  nasal  pharyngeal  tube  was  used  as  the  airway  during 
NACV  (Portex  Inc.,  Wilmington,  MA).  NACV  was  achieved  with  the  Star 
Sync  Patient  Triggered  Interface  and  either  the  Infant  Star  200  or  500 
mechanical  ventilators  (Infrasonics  Inc.,  San  Diego,  CA).  With  StarSync 
in  the  assist/control  mode,  the  ventilators  were  triggered  to  give  a 
pressure-limited  breath  with  each  spontaneous  breath  as  determined 
via  the  Star  Sync  abdominal  pressure  transducer.  The  settings  used 
were  a:  PIP  of  16  to  18cmH20,  PEEP  of  6  to  8  cmH20,  flow  of  20  ±  5 
LPM,  Fi02  of  0.21  to  0.40,  IT  to  match  the  Star  Sync  spontaneous 
displayed  value  and  a  backup  rate  of  20  BPM.  Once  PEEP  was  <  8 
cmH20,  weaning  from  NACV  was  attempted  by  reducing  PIP  as 
tolerated  (lack  of  tachypnea  and  retractions).  A  period  of  nasal  CPAP 
was  used  prior  to  removing  the  nasal  pharyngeal  airway  and  low-flow 
nasal  cannula  oxygen  therapy  or  room  air  followed. 
RESULTS:  NACV  was  used  on  16  children  with  evidence  of  impaired 
ventilatory  function,  i.e.,  >  10  days  post-operative  mechanical  ventilatory 
support  with  tachypnea,  retractions  and  a  spontaneous  VT  of  <  5  cc/kg 
on  pressure  support  (Servo  300  or  900C,  Siemens-Elema,  Danvers, 
MA).  Two  children  had  diaphragmatic  hemiparesis.  Heliox  was  added 
to  NACV  in  three  children  with  severe  airway  stridor  unresolved  with 
aerosolized  racemic  epinephrine  and  intravenous  Decadron.  Patients 
were  £  6  kg  in  weight  and  were  recovering  from  a  sternotomy  approach 
complex  cardiac  repair  (e.g.,  Norwood  stage  1)  or  cardiac  transplant. 
NACV  was  used  for  6  ±  4  days  with  successful  weaning  in  all  cases. 
CONCLUSIONS:  Nasal  Assist  Control  Ventilation  is  a  novel  bridge 
between  mechanical  ventilation  and  unassisted  ventilatory  support. 
NACV  has  been  used  successfully  in  the  postoperative  care  of  children 
recovering  from  surgical  correction  of  complex  heart  defects. 

OF-95-217 


INACCURATE  STATIC  INSPIRATORY  PRESSURES  IN  MECHANICALLY 
VENTILATED  PATIENTS  WITH  ACUTE  LUNG  INJURY    Jonathan  B  Wauori' 
Thomas  L  Clanton1,  Timothy  B  Op  t  Holt1  James  E  GadekV  ■*■  From 
Cardiopulmonary  Care  Sciences  Department,  Georgia  State  Unwersity.  Atlanta 
GA    "*"  From  Pulmonary  and  Critical  Care  Medicine,  The  Ohio  State  University 
Columbus,  OH 

INTRODUCTION:  Static  respiratory  system  compliance  (CHB),  the  change  in  lung 
volume  per  unit  of  pressure  change  during  an  inspiratory  hold,  measured  during 
machine  breaths  of  mechanically  ventilated  patients  is  often  used  to  help  guide 
ventilator  management  decisions    This  measurement  is  assumed  by  many 
clinicians  to  be  an  accurate  measurement  of  the  sum  of  lung  and  chest  wall 
compliance  only    We  tested  the  hypothesis  that  the  static  airway  pressures  used 
to  calculate  respiratory  system  compliance  of  animal  subjects  with  acute  lung 
injury  measured  immediately  before  and  after  death  would  be  significantly 
different    METHODS:  Nineteen  anesthetized  mongrel  dogs  received  phorbol 
mynstate  acetate  (25-30  ug/kg),  an  agent  used  to  induce  permeability  edema  lung 
injury,  and  a  continuous  infusion  of  normal  saline  at  10  mL.kg  '»hr  over  a  7  hour 
period    The  animals  were  mechanically  ventilated  with  a  Bear  I  ventilator  with 
constant  flow  breaths  of  15  mL/kg  body  weight  Static  airway  pressures  were 
measured  at  the  ventilator  circuit  Y-piece  at  the  end  of  3  second  inspiratory  breath 
holds,  within  three  minutes  before  and  after  death  to  determine  if  unobservable 
expiratory  efforts  were  altenng  values    RESULTS:  Post-death  static  inspiratory 
pressures  were  significantly  lower  and  static  Cfls  measurements  were  higher  than 
pre-death  measurements  according  to  paired  T-test  analysis  (p=0  004  for  both) 


Vent  Plateau  Press 
(n=19)cm  H,0 


Static  CRS(n=1 9 
mL/cm  H20 


Pre-death 
Post-death 


10  7±1  9,  [7  5,  15] 


26  7*6  6,  (14  9.  36  4] 


31  8±7  4,  (20  8,48  2] 


(results  given  as  meantSD,  [rr 


*)> 


This  significance  was  obtained  even  though  decreases  in  static  airway  pressure 
from  pre-death  to  post-death  of  greater  than  1  cm  H;0  were  observed  in  only 
52  6%  of  the  subjects    CONCLUSIONS:  The  results  suggest  that  some 
additional  vanable/s,  perhaps  expiratory  muscle  activity,  contnbuted  to  the 
exaggeration  of  pre-death  CRS  values    The  influence  is  not  consistently  present  in 
ventilator  patients  with  lung  injury,  making  efforts  to  calculate  corrections  difficult. 


S:   A  CASE  STUDY  Thenaa  Rva*  lllllllrl 

ea**.  US,  BUT.  RPrT.  M  S««^ 

Uinkc  P   ll.x.r.k,  MM,  RRT,  F/P  Speau, 

Coataxh**,  MD,  Rodolfo  1.  Godhaei,  MD,  PhD,  The  ChlUrca'i  HoaaHal  of 

Philadelphia,  Philadelphia,  PA 

PATIENT  DATA  AND  CASE  SLA 

MAJ.Y   THu  k  M  almort  J  Vear  o 

d  prev.ou.ly  well  boy  with  group  B  ttrq>  tepeia. 

fa^otorrorofruanght  lower  etfreri 

ir.  tecondary  to  compartment  fyndrome  Port- 

opcmuvc  oamplicalion  included  acute  renaJ  failure.  AH I  is,  and  cubculaneoui  cmphyvcma-  Immediately  port-operatively 

cm  H,0  A-a  DO,  ww  equal  to  240  mm  Hg. 

ne  A-a  DO,  wae  equal  to  32  J  mm  Hg    Chert  » 

an  Mr!    Thrw  day* port-op.  rn  the  f at 

Siemam  Servo  300  Th«  followig  ch 

DeyofVemilabor.                Tone 

Peak  Infilling  Preaaurc                PEEP 

Day  1                     3.00  AM 

SIMV                   360  ml 

30cmH20                            8 

Day  2                     5  00  AM 

S1MV                   360  ml 

32cmH20                            12 

Day3                     100PM 

SIMV                   300  ml 

62  em  H20                            11 

Day  4                       11  00  AM 

SIMV                   300  ml 

63  cm  H20                            13 

Day  4                     1  00  PM 

SIMV                   2 SO  mi 

3»cmH30                            13 

Day*                    2  00  PM 

saw            no  mi 

62  cm  H  20                           IS 

Day  4                    3:00  PM 

PRIC                  220  ml 

47emH20                           12 

Day  4                     9  40  PM 

PRVC                  120  ml 

40  cm  1120                            12 

Day  12                    3  00  PM 

VS                    (180  ml) 

37cmH20                            8 

Day  13                    7  00  AM 

VS                    (170  ml) 

23  cm  1120                            8 

After  being on  PRVC  for 

wcmwHo'IIohHtO    Med.Ml.on 

SIGNIFICANCE  OF  THF.  CASK; 

palter*  Tha  availability  of  thu  mod* 

OF-95-031 

CONTINUOUS  NEGATIVE  PRESSURE  VS.  NASOPHARYNGEAL  CPAP  IN  RSV,  A 
CASE  STUDY  Theresa  Rvan  Schultz.  BA.  RRT.  P/P  Spec..  Linda  Allen  Napoll,  BS, 
RRT,  RPFT,  P/P  Spec,  Lorraine  F.  Hough,  MEd,  RRT,  P/P  Spec,  Andrew  Coalarino, 
MD,  The  Children'!  Hoipilal  of  Philadelphia,  Philadelphia,  PA 

PATIENT  DATA  AND  CASE  SUMMARY:  A  3  month  old  former  32  week  premature 
infant  was  admitted  to  the  hospital  and  diagnosed  with  RSV  bronchiolitis.  This  patient  had 
been  hospitalized  for  the  first  one  month  of  life,  twenty-four  hours  of  which  she  required 
positive  pressure  ventilation  After  her  initial  discharge  to  home  she  was  reportedly  well  until 
2  days  pnor  to  admission  to  our  institution  The  patient  was  admitted  to  the  Regular  Inpatient 
Care  Area  for  three  days  prior  to  her  transfer  to  the  Pediatric  Intensive  Care  Unit  (PICU). 
Physical  assessment  of  this  patient,  at  the  lime  of  transfer,  included  increased  work  of 
breathing,  wheezing,  flanng,  retracting  and  decreased  food  intake    Chest  x-ray  revealed  right 
upper  lobe  infiltrate  vs  atelectasis    Laboratory  data  confirmed  Impending  Respiratory 
Failure  Initial  artcnal  blood  gas  analysis  revealed  7  3 4/54/5 2/2 9/+ 2/  84%  while  on  FiO:  3 
Respirations  were  70  Upon  arrival  to  the  PICU,  the  patient  was  placed  on  nasopharyngeal 
CPAP  +10  cm  HjO.  FiOj  4,  with  continuous  aerosolized  albuterol  at  2  cc/hr  which  was 
weaned  to  Q2H  nebulizer  treatments  within  5  hours  This  patient  remained  on  CPAP  +10  cm 
HA  FiOj  4  for  three  days  with  respirations  52-70  and  heart  rate  186-200+ ,  Over  the  course 
of  these  three  days  it  was  necessary  to  replace  the  nasopharyngeal  tube  four  times  secondary 
to  airway  plugging/displacement  Each  time  the  nasopharyngeal  airway  needed  to  be 
replaced,  the  patient  was  compromised  due  to  inadequate  CPAP  and  Oj  delivery.  This 
resulted  in  cyanosis,  tachypnea,  bradycardia  and  acidosis  At  the  end  of  the  three  days  of 
nasopharyngeal  CPAP  the  patient's  Chest  x-ray  was  consistent  with  diffuse  bilateral 
hyperinflation,  progressive  bibasilar  atelectasis  with  worsening  nght  upper  lobe  air  trapping 
and  atelectasis  Due  to  the  problems  associated  with  nasopharyngeal  CPAP,  as  noted  above. 
Continuous  Negative  Pressure  was  considered  as  an  appropriate  substitute  Research  has 
demonstrated  thai  Continuous  Negative  Pressure  and  CPAP  are  physiologically  equivalent. 
CPAP  was  discontinued  after  three  days  and  Continuous  Negative  Pressure  (-15  cm  H:0)  via 
the  Emerson  Iron  Lung,  an  infant  negative  pressure  ventilator,  was  utilized.  Nebulized 
albulcro)  treatments  continued  every  two  hours  Physical  assessment  of  the  patient  while  in 
i  he  negative  pressure  revealed  respirations  30-40,  heart  rate  150-170  On  the  third  day  of 
intervention  with  negative  pressure,  we  began  to  give  the  child  inals  out  of  the  Iron  Lung  We 
increased  the  amount  of  time  out  each  day  as  tolerated  over  the  next  three  days  On  day  six  of 
continuous  negative  pressure  ventilation,  the  patient  had  been  out  of  the  iron  lung  for  over 
twenty-four  hours  and  was  transferred  to  the  Regular  In-patient  Care  Area  on  15  liter  nasal 
cannula  Chest  x-ray  at  that  time  revealed  right  upper  lobe  atelectasis  stable  with  slight  apical 
clearing,  otherwise  aeration  was  satisfactory   Two  days  after  transfer  back  to  the  Regular 
Inpatient  Care  Area  the  patient  was  weaned  to  room  air  with  oxygen  saturations  equal  to 
95%  The  patient  was  discharged  to  home  ten  days  after  the  institution  of  continuous  negative 
pressure  SIGNIFICANCE  OF  THE  CASE:  Continuous  Negative  Pressure  Ventilation 
appeared  to  be  an  appropnalc  allcrnalivc  lo  nasopharyngeal  CPAP  in  this  patient 


1158 


Respiratory  Care  •  NOVEMBER  '95  Vol  40  No  1 


Saturday,  December  2,  3:00-4:55  pm  (Rooms  230A-B) 


NEGATIVE  PRESSURE  VENTILATION  IN  RSV:  A  CASE  SUMMARY  Theresa 
Rvan  Schultt.  BA.  RRT.  P/P  Spec.  Lloda  Allen  Napoll,  BS,  RRT,  RPFT.  P/P  Spec, 
Lorraine  F.  Hough.  MEd,  RRT,  P/P  Spec,  Maureen  O'Rourke,  MD,  The  Children's 
Hospital  of  Philadelphia.  Philadelphia,  PA 

PATIENT  DATA  AND  CASE  SUMMARY:  A  10  month  old  child  with  a  history  of 
wheezing  once  prior,  was  transferred  to  our  Emergency  Department  from  an  outlying 
hospital  Chief  complaints  included  fever  for  two  days,  decreased  food  intake,  vomiting, 
cough  and  increased  work  of  breathing  The  child  had  been  diagnosed  with  otitis  media  by  his 
Primary  Medical  Physcian  a  few  days  prior  to  presentation  Upon  arrival  to  our  hospital,  the 
patient  was  tachypnoe  and  tachycardic  He  was  wheezing  and  demonstrated  a  significant 
oxygen  requirement  Home  medications  included  amoxicillin  and  ventolin  syrup.  This  patient 
was  treated  in  the  Emergency  Department  with  continuous  aerosolized  albuterol  at  2  cc/hr, 
FiO;  1  0,  ampicillin  and  a  NSS  bolus  Laboratory  data  confirmed  that  the  patient  was  in 
Impending  Respiratory  Failure  and  was  positive  for  RSV  Initial  arterial  blood  gas  analysis 
revealed  7  34/47/137/25  on  FiOi  1.0.  Chest  x-ray  revealed  peribronchial  thickening  with 
hyperinflation  of  lung  fields,  right  upper  lobe  and  left  lower  lobe  pneumonia  The  patient 
remained  tachycardic  and  tachypnoe  with  retracting  and  nasal  flaring  despite  interventions. 
A  few  hours  after  presentation  he  began  to  desaturate  to  90%  while  on  FiO;  1  0.  Upon  arrival 
to  the  PICU,  the  patients  respirations  were  70-100,  heart  rate  was  174-189.  and  oxygen 
saturation  was  97%  on  FiOi  1.0.  It  was  considered  that  this  patient  would  have  only  required 
an  artificial  airway  in  order  to  provide  mechanical  ventilation  Since  this  patient's  natural 
airway  was  in  tact,  we  attempted  to  provide  ventilatory  support  with  Continuous  Negative 
Pressure  This  patient  was  placed  in  the  Port-A-Lung,  a  pediatric  negative  pressure  ventilator, 
and  assisted  with  a  continuous  negative  pressure  of  20  cm  H;0  Three  hours  after  Continuous 
Negative  Pressure  was  initiated,  his  oxygen  requirement  was  35.  respiratory  rate  70.  heart 
rate  145,  and  blood  pressure  105/69  The  patient  remained  on  continuous  aerosolized 
albuterol  while  in  the  negative  pressure  for  12  hours,  after  which  Lime  the  albuterol  was 
weaned  to  Q2H  Twenty-four  hours  after  the  initiation  of  continuous  negative  pressure, 
clinical  data  and  physical  assessment  indicated  improvement  in  ventilatory  status  Trials  out 
of  the  Port-A-Lung  were  begun  Respirations  were  50-60.  heart  rate  150.  oxygen  requirement 
25  via  aerosol  mask  Chest  x-ray  revealed  persistent  peribronchial  thickening  with  interval 
worsening  of  right  upper  lobe  and  left  lower  lobe  atelectasis  vs.  infiltrate  Forty-eight  hours 
after  admission  to  the  PICU.  the  patient  required  oxygen  at  1  5  liters  via  nasal  cannula  to 
maintain  oxygen  saturations  greater  than  95%  He  remained  out  of  negative  pressure, 
breathing  comfortably  ai  40-60  times  a  minute,  heart  rate  was  129-142  Seventy-two  hours 
after  admission  to  the  PICU  the  patient  was  transferred  to  the  Regular  In  Patient  Care  Area 
on  15  liter  nasal  cannula  and  Q3H  albuterol  treatments  The  patient  gradually  weaned  off  his 
oxygen  and  was  discharged  after  7  days  (168  hours)  SIGNIFICANCE  OF  THE  CASE: 
Continuous  Negative  Pressure  Venlilauon  was  a  safe  and  effective  intervention  for  this  10 
month  old  patient  with  RSV  pneumonia/Impending  Respiratory  Failure 


UNIV6RSITV  OF   LOUISVILL6 

fnCULTV  POSITION  IN  R6SPIRATORV  CFIR6 

The  University  of  Louisville,  School  of  Allied  Health  Sciences,  is 
seeking  an  individual  to  assume  a  full-time,  tenure  track  position  in 
the  Respiratory  Care  Program.  This  well  established  program  offers 
two-  and  four-year  degrees.  Responsibilities  include  directing  clinical 
education,  classroom  and  laboratory  teaching  and  service  to  the 
School,  University,  community  and  profession. 

The  successful  candidate  must:  be  a  registered  Respiratory  Therapist, 
have  three  years  teaching  experience  and  have  an  earned  master's 
degree  in  a  related  discipline.  Preference  will  be  given  to  candidates 
with  a  strong  background  in  adult  critical  care  and  with  an  earned 
doctorate.  Rank  and  salary  are  commensurate  with  experience  and 
qualifications. 

The  deadline  for  application  is  1 2  January  1 996,  and  the  position  will 
be  available  01  July  1996.  Send  letter  of  interest,  curriculum  vitae, 
and  arrange  for  3  letters  of  recommendation  to  be  sent  under  separate 
cover  to: 

Dr.  Susan  A.  Miller 
Associate  Professor 
School  of  Allied  Health  Sciences 
104  Carmichael  Building 
University  of  Louisville 
Louisville,  KY  40292 

The  University  of  Louisville  is  an  Affirmative  Action/Equal  Opportunity 
Employer.  Women  and  minority  candidates  are  encouraged  to  apply. 


\ML 


ARMY 

RESPIRATORY 

THERAPY 

SPECIALIST: 

EXPERIENCE 

PLUS  BENEFITS 

Bring  your  skills  as  a  certi- 
fied Respiratory  Therapist  to  an 
organization  that  respects  and 
values  your  training:  Today's 
Army.  Work  with  expert  medical 
staffs  using  the  latest  equipment. 

Plus  your  skills  earn  you 
great  benefits  you  won't  find  in 
many  other  places.  Enlist  for 
4  years  and  receive  an  $8,000 
bonus  plus  qualify  for  college 
loan  repayment  of  up  to  $55,000. 
Enlist  for  3  years  or  4  years  and 
be  eligible  for  the  Army  College 
Fund  of  up  to  $30,000. 

Call  or  visit  your  local  Army 
Nurse  Recruiter  for  more 
information  on  how  to  become 
an  Army  Respiratory  Therapy 
Specialist. 

1-800-USA-ARMY 
Extension  487 


ARMY. 
BE  ALL  YOU  CAN  BE. 


Circle  133  on  reader  service  card 


Circle  94  on  reader  service  card 
Visit  AARC  Booths  242  and  244  in  Orlando 


159 


Saturday,  December  2,  3:00-4:55  pm  (Rooms  230C-D) 


EFFECT  OF  CLINICAL  GUIDELINES  IN  REDUCING  UNNECESSARY  RESPIRATORY 
CARE  IN  NON-ICU  PATIENTS 

JohnSqtllo.BA.RRT,  Ponce  imnci.m.B.vRHl.H I  Piicvstr>,MD.,Divid  Shulklo,  Ml), 

Mkbacl  Sintoro,BS.RR  I  .J.il.n  HaoKO-FlucbcD,  MD  Lyndi  Gradwril,  MS,  RRT, 
L'niv* r»m  of  Peoniylvinli  Medfcit  CcoKr. 

INTRODUCTION   Effort*  10  contain  unnecessary  utiUiation  of  mpiratory  can  modaUrie*  bai 
become  a  major  concern  in  rvctol  yean.  Ai  maoaged  cart  continues  to  re-ibape  the  market, 
cott-emclenl  ai  welJ  u  cfTIcBclotu  care  will  be  key  Ingredient!  to  the  viability  of  healtb  care 
fai  ilinn  throughout  the  country.  We  identified  aeveral  reaplratory  care  modaUtie*  which 
hbtorkmlh  have  been  ovenucd  al  our  Inirirurton    These  respiratory  care  modalitks  Includes: 
inbated  broocbodUalor  delivery  (SVN-HHN.MDI).  Cbeil  Physical  Therapy  ( CPTl,  and  Oiygen 
Tbenipy.  METHODS;  Clinical  guidelines  were  formulated  for  ibe  modalities  mentioned  above 
by  a  multidbciplinary  team  wbicta  Included  nurses,  physicians,  and  respiratory  therapbD. These 
guidelines  were  consbled  with  the  guidelines  establbhed  by  the  AARC  for  HHN.MDLOrygco 
tbcrapy,  and  CPT  A  randomised  study  was  conducted  on  noa-ICU  patients  evaluating  ibe 
appt   priateness  of  physician  ordered  HHN,MDl,oiygen  (herapy  and  CPT  using  the  approved 
cllnkkl  guidelines    Evaluation  of  appropriateness  Included  a  physical  assessment,  and  medical 
chart  review.  This  evaluation  was  conducted  prior  to  publishing  and  subsequent  dbtributioo  of 
the  clinical  guidelines  to  tbc  bouscstaff   After  approximately  1  year  of  publbhlng  the  clinical 
guidelines,  another  randomised  study  using  the  same  methodology  was  conducted  RESULTS 

Sample  Size 

1993  1994 

Oxygen  Therapy  (OT)  64  62 

Medication  therapy  (MT)  123  73 

Chest  Physical  Therapy  (CPT)  52  35 


CONCLUSION;  Clinical  guidelines  and  education  has  generally  failed  to  reduce  uauaenamary 
respiratory  care  at  our  uutituttoa   Although  there  has  been  some  improvement  In  the  utiloaiwo 
of  CPT,  Inhaled  medication  delivery  and  oiygen  therapy  has  shown  little  Improvement.  A 
consultative  or  evaluation  program  which  ei amines  the  appropriateness  of  the  above  meeitlooed 
respiratory  care  modalities  b  the  neit  strategy  we  will  implement  Research  has  suggested  that  a 
consultative  service,  which  Incorporates  clinical  guidelines,  has  been  successful  In  reducing 
unnecessary  care  and  providing  appropriate  cart  to  those  patients  In  need.  We  will  study  the 
effects  of  thb  strategy  In  the  neit  year. 

OF-95-0C 


A  SURVEY  OF  BLOOD  GAS  USAGE  IN  AN  URBAN  TEACHING  HOSPITAL  MR1CU 
IMPLICATIONS  FOR  REDUCING  UTILIZATION  OF  RESOURCES  Whilne\  L  Schwartz. 
BA.  RRT.  ihe  MR1CU  Respiratory  Care  Stall  Herbert  Patrick  MD.  Department  of 
Respiratory  Care,  Thomas  Jefferson  University  Hospital,  Philadelphia,  PA 

Introduction  Blood  gases,  whether  ABG's  or  MVBG's.  arc  invasive,  expensive,  and  touted  to 
be  overused  in  all  ICU's  We  surveyed  the  utilization  of  blood  gases  in  our  MRJCU  over  a 
penod  of  6  weeks  to  determine  the  appropnalcncss  of  the  requests  and  to  discover  ways  lo 
make  this  resource  more  cost  effective  Methods  A  convenient  pocket  si/cd  survey  form  was 
developed  to  determine  data  on  each  gas  requested,  the  form  was  completed  by  a  rcspiraton 
therapist  The  requesting  party  would  be  identified  and  asked  the  reason  for  the  gas 
oxygenation,  ventilation.  pH,  mctabolics,  weaning,  code,  or  a  combination  The  therapists 
were  instructed  not  to  dissuade  the  requesting  party  from  requesting  a  gas  even  if  the 
therapist  fell  ihc  requesi  was  not  appropriate  Results  Approximately  400  blood  gascVmonth 
arc  requested  in  the  MRJCU  Over  the  penod  of  the  survey .  iherc  were  approximately  580 
gases  requested  and  279  of  these  were  surveyed,  resulting  in  a  sample  representing  48%  The 
blood  gases  represented  92%  artcnal  and  8%  mixed  venous  blood  gases 

Utilization  of  blood  gases 


Shift 

Da\ 

Boning 

siiRtu 

TOTAL 

Residents 

7 

17 

6 

30 

Interns 

45 

45 

52 

14: 

Nurses 

19 

24 

22 

65 

Other 

20 

14 

8 

42 

TOTAL 

91 

1UII 

88 

279 

Between  day ,  cv  cning.  and  night  shifts,  the  number  of  blood  gases  did  not  van  significantly 
02%,  35%  and  31%  respectively)  Of  the  total  blood  gases,  the  residents  ordered  30/279 
(7  5%),  interns  ordered  142/279  (53%),  nurses  requested  65/279  (28%).  pulmonary-critical 
care  fellows  ordered  2%  respiratory  care  practitioners  requested  2%  and  mullidisciplinan 
requests  were  10%  Eighteen  percent  of  the  total  blood  gases  were  requested  for  oxygenation 
alone,  despite  availability  of  continuous  oximetry   Evening  shift  showed  an  increase  in  the 
number  of  ABG's  ordered  by  residents  w  hich  may  reflect  the  cross-coverage  policy  for 
evening  houscsiaff  in  ihc  MRJCU  Conclusions  This  survey  reveals  that  requests  for  blood 
gases   1 )  were  evcnlv  distributed  throughout  each  shift,  2)  were  requested  predominated  from 
two  groups,  the  interns  and  the  nurses,  and.  3)  were  inappropriate  18%  of  the  lime  due  to  the 
availability  of  continuous  oximetry  Our  survey  indicates  that  educational  efforts  to  reduce 
utilization  of  blood  gases  must  span  all  shifts  while  targeting  both  interns  and  nurses 


IMPROVING  THE  UTILIZATION  OF  CPT  IN  A  PEDIATRIC  POPULATION.  John  W. 
Salyer  BS,  RRT,  Karen  Kay  Burton  RN,  RRT.  Kalhy  Poll  RRT.  Primary 
Children's  Medical  Cenler.  Sail  Lake  City,  Ulah.  Introduction:  We 
speculated  thai  Chest  Physical  Therapy  (CPT)  was  being  over  utilized  in  our 
lacilily  and  thus  sought  to  develop  a  program  to  oplimize  ils  use,  Methods; 
Guidelines  (or  the  use  of  CPT  were  developed  collaboratively  and  approved  by 
Ihe  hospital  medical  executive  committee  and  appropriate  (acuity  members  at 
(he  school  of  medicine.  RCP's  were  encouraged  to  use  the  guidelines  lo  initiate 
a  dialogue  with  medical  and  nursing  stalfs  about  optimal  CPT  ulilizalion,  but 
were  directed  not  to  refuse  to  do  ordered  therapy  that  appeared 
inappropriate.  An  extensive  hospital  wide  training  program  was  conducted 
with  our  staff  and  nursing  staff-  Every  patient  on  CPT  was  assessed  when  Ihe 
order  was  written,  to  see  if  this  therapy  was  appropriate  and  the  results  of 
these  assessmenls  were  tabulated.  These  data  were  analyzed  with  respect  to 
the  proportion  of  all  CPT  inappropriately  ordered,  or  inappropriately 
administered,  along  wilh  cosl  to  administer  this  therapy.  The 
appropriateness  data  were  then  reported  to  various  nursing  and  medical 
services.   The  program  was  implemented  in  March  ol  1994.   We  used 
statistical  process  control  techniques.  Results:   We  found  thai  the 
proportion  of  all  CPT  orders  that  were  inappropriate  was  =  45%  before  the 
guidelines  were  implemented,  and  =  40%  after.  However,  after  the  guidelines 
were  implemented,  the  %  of  inappropriate  CPT  actually  administered 
dropped  to  -  10%.  There  was  a  reduction  in  utilization  of  CPT  of  52%  when 
Indexed  to  patient  days,  with  a  corresponding  reduction  In  cost  to  administer 
this  therapy  of  66%  or  «  $73,000/year 

Total  Number  of  CPT  Tx"s  {indexed  to  pt  days) 


q  oso   a  r\ 

go,ol/V./,   h/    \         ,      - 

i  °  3°  t      "     \  /\/\ 


Guidelines 
Implemented 


0.20  ■ 
fc  o.io 

0.00 


s    s    s    s 


5   i 


— • INDEXED  TOTAL  CPT  TX  ■ 


S      3      S      i      i      i 
x      -»     a      <      1      <      o 

-MEAN UCL LCL 

(.2SD)      (-2SD) 


Conclusion:  This  program  was  ellecllve  In  Improving  Ihe  utilization  of 
pediatric  CPT. 


OXYGEN  THERAPY    PRACTICE    PATTERNS    FOR    NON-ICU 
PATIENTS  INDICATES  THE   NEED  FOR  TOOLS  TO  STANDARDIZE 
OXYGEN   THERAPY    ADMINISTRATION 

Sandy  M  Melcalf  RRT.  Xiaoping  Zhang,  MD,  Jane  Wallace.  RN,  MS, 
Wang  Hsueh-fen  Young,  MS,  Loren  Greenway,  RRT,  and  Alan  H 
Morris,  MD.  Pulmonary  Division/Respiratory  Care,  LDS  Hospital,  8lh 
Avenue  and  C  Street,  Salt  Lake  City,  UT  84143 


Although  guidelines  for  oxygen  therapy  administration  are  available 
(RespCare  91,36:1410,  Chest  86:90:647),  they  have  not  been  reported  to 
be  routinely  applied  or  shown  to  improve  oxygen  therapy  practice  patterns 
in  non-ICU  patients.  We  retrospectively  reviewed  data  from  a  large, 
integrated  hospital  information  system  (HELP)  at  the  LDS  Hospital  in 
order  to  determine  oxygen  therapy  practice  patterns  in  our  hospital.  We 
identified  339  patients  who  were  given  oxygen  therapy  at  any  time  during 
their  stay  on  one  medical  and  one  surgical  ward  from  1/1/94  to  3/31/94. 
We  retrieved  6,362  routine,  clinical  Sp02  measurements  and  associated 
oxygen  therapy  status.  A  simple,  quantitative  definition  for  excessive, 
reasonable  and  insufficient  use  of  02  is  shown  in  Table  1.  Of  the  790 
measurements  in  the  category  of  insufficient  use  of  oxygen,  250  (32%) 
were  not  associated  with  oxygen  administration,  and  540  (68%)  were 
associated  with  oxygen  administration.  We  concluded  the  following:  (1) 
oxygen  therapy  for  non-ICU  patients  was  not  effectively  administrated  in 
our  hospital,  (2)  we  suspect  those  observations  are  a  reflection  of  a 
widespread  problem  in  the  medical  community  (Chest  92:102:1672,  AJM 
92:92:591).  Tools  to  standardize  and  improve  the  quality  of  oxygen 
therapy  administration  at  the  point  of  care  arc  needed.  Computerized 
protocols  designed  to  provide  specific,  executable  instructions  at  the  point 
of  care  offer  a  solution  lo  the  problem  and  need  to  be  evaluated  in  terms  of 
their  ability  to  reduce  excessive  use  of  oxygen  and  the  incidence  and 
duration  of  hypoxemia. 

Table  1.  Oxygen  Therapy  Classification 


Category 


Dttinltl 


LOS  In  hi 
(*  of  ton 


Me 


(») 


Excasive  use  of  02  SpO^IJ*  w/02                 10,349  (31)  2.128(33) 

Rctaomble  u«  of  02  or  Sp02  90  93%  w/02  & 

no  mo  of  02  SpO2  290w/oO2               20,775(62)  3,444(54) 

lnsulT,ciciini«0fO2  Sp02:j89% 2.JM   (7)  790(12) 


Told 


33.  528 


6.362 


LOS  =  wtid  length  nf  Mnv   „/  -  uuli,  w/o  =  wiilioul   O:  =  osyn.-n  Ihernpy 


I  1 60 


RESPIRATORY  CARE  •  Novumbkr  '95  Vol  40  No  1 1 


Saturday,  December  2,  3:00-4:55  pm  (Rooms  230C-D) 


A  CLINICAL  TRIAL  OF  COMPUTERIZED  OXYGEN  THERAPY  PROTOCOL 
FOR  NON-ICU  PATIENTS 

Sandy M  Malcalf.  R.R.T..  Xiaoping  Zhang.  M  D  .  C  Jane  Wallace.  RN.MS.A  Tupper  Kinder,  B  S  , 
Loren  Gieonway.  RRT  and  Alan  H  Morns.  M  D  Pulmonary  Drvtsion/Respnalory  Care.  LDS  Hospital, 
8tn  Avenue  and  C  Street.  Salt  Lake  Crry.  UT  84143 

In  order  to  deliver  standardized  care  at  the  bedside  and  improve  the  quality  of  oxygen  therapy, 
we  developed  a  computerized  oxygen  therapy  protocol  (COTP)  for  non-ICU  patients,  and 
integrated  it  into  the  LDS  Hospital's  HELP  computer  system    We  defined  excessive  use  of 
oxygen  (Excessive)  as  Sp02>94%  with  oxygen  therapy,  reasonable  use  or  reasonable  non-use 
of  oxygen  (Reasonable)  as  Sp02  between  90%  and  93%  with,  or  SpO2>90%  without  oxygen 
therapy,  and  insufficient  use  of  oxygen  (Insufficient)  as  Sp02£89%  with  or  without  oxygen 
therapy    The  basic  COTP  logic  is  increase  oxygen  therapy  whenever  Insufficient,  decrease 
whenever  Excessive,  and  maintain  current  oxygen  therapy,  if  any,  for  at  least  12  hours  before 
a  further  decrease  in  therapy,  if  the  Sp02  is  90-93%    Oxygen  therapy  data  from  1/1/94  to 
3/31/94  (339  patients)  before  the  use  of  COTP  in  one  medical  and  one  surgical  ward  of  our 
hospitaJ  was  used  as  a  historicaJ  control    Thereafter,  COTP  was  put  into  routine  use  in  the 
same  wards  from  1 1/1/94  to  3/31/95  (706  patients)    The  results  are  shown  in  Table  I  and  2 


Tabta  1.  Oxygen  Therapy  Classification  Before  (1/94-3/94)  ft  After 

(11/94-3/95|th« 

Use  of  COTP 

Measurements                        Duration  in  Hours 

MeantSEM   Inlervar" 

Before          After         P             Before            After 

P         Before 

After        P 

Excessive     2128(33%)  4333(40%)  <0.01     10349(31%)  21653(31%) 
Reasonable  3444(54%)  5501(50%)  <0  01    20775(62%)  45970(66%; 
Insufficient     790(12%)     1023(9%)  <0  05     2404((7%>      2568(4%) 

1        4  9t0  1  4  5t0  1    <001 
<0  01     6  0±0  1  8  410  2  <0  001 
<0  01    3  0±0  2  2  5x0  1    <0.01 

Total              6.323          10,857                      33,528           70,191 

Table  2.    HypoxemuafSp02  87V.  fof>3  Min]  Belore(1/94-3/94)  ft  After 

11/94-3/95)  the 

Use  of  COTP 

Before                       After                       P 

Hypoxemia  Incidence                         5  7%{349«323)     4 
MeantSEM  Hypoxemia  Index  (¥.hoursr              17.2±29  6 

3%(470/10857) 
14  4124  5 

<0  001 
0  145 

02  Therapy  Change  Following  hypoxemia 

02  Therapy  Increase                          55%(167/304f) 
No  02  Therapy  Changes                      40%(1 22/304) 
02  Therapy  decrease                             5%(1 5/304) 

73%(306/421t) 
25%{1 04/421) 
3%(11/421) 

<0  01 
<0  01 
<0  05 

t  Excluded  tftose  unaWe  to  evaluate  because  of  mosmo  data  ana  those  already  receiving  maximum  02  Therapy 

Table  1  indicates  that  COTP  has  been  followed  bv  a  reduction  of  the  incidence,  duration,  and 
mean  interval  of  insufficieni  use  of  oxygen  but  not  by  a  reduction  in  duration  of  excessive  use 
of  oxygen    Table  2  indicates  that  COTP  has  been  followed  by  an  increase  in  appropriate 
response  to  hypoxemia  (oxygen  therapy  increase)  and  a  decrease  m  inappropriate  respoi 
(oxygen  therapy  decrease  or  no  change)    These  data  suggest  thai  our  COTP  for 
patients  is  favorable 


rcu 


Pediatric  Oxygen  (02)  Weaning  Protocol:  Successful  Implementation  and  Co 

Savings 

M.  Miller.  RRT.  T   Mitchell,  RRT  and  D   Habib  MD    Medical  University  ol  South 

Carolina  Children's  Hospital,  Charleston,  South  Carolina 

Objective:  To  develop  a  Pediatric  02  Weaning  Protocol  that  is  effective  in  reduci 

unnecessary  02  administration  and  patient  charges  lor  general  ward  patients 

Materials  and  Methods:  A  literature  search  revealed  no  previous  information  on 

pediatric  02  weaning  protocols    Physician  surveys  were  distributed  lo  the  Pediatr 

)hysicians  (n=22)  to  determine  their  02  weaning  preferences,  i  e  -  Irequency  and 

ncrements  ol  weaning,    methods  ol  02  delivery  and  the  use  of  pulse  oximetry 

Jased  on  the  results  of  the  physician  survey  and  Clinical  Practice  Guidelines  lor 
adult  02  weaning,  a  pediatric  protocol  was  developed   The  protocol  was  designee 
1.  tdenirty  potential  patients  lor  weaning  (Sp02's  >95%)  2   wean  patients  by  stan 
parameters:  Sp02>  95%,  q3  hour  intervals,  5%  or  0.5  liter  decrements,  to  room  < 
specified  physician  parameters  3.  monitor  the  patient  for  any  adverse  outcomes 

hrough  occurrence  reports  (documentation  of  respiratory  distress/  failure  associa 

with  the  weaning  process)  and  twelve  hours  ol  post-weaning  pulse  oximetry 

4   reinforce  patient  assessment  and  monitoring  during  the  weaning  process    The 

>rotocol  was  applied  to  all  general  pediatric  patients  with  both  acute  and  chronic 
needs,  except  post-op  cardiothoracic  patients  and  patients  with  sickle  cell  disease 

'alients  were  stabilized  lor  twelve  hours  on  02  therapy,  unless  ordered  by  the 
ohysician  to  initiate  the  protocol  earlier.  Protocol  efficiency  was  determined  by 

eviewing  ten  randomly  selected  pre-protoool  and  10  post-protocol  02  patients  (1 
3cu1a/1  chronic)  lor  number  (#)  of  Sp02  checks,  #  of  Sp02  checks  >95%,  #  of 
decreases  or  Increases  In  02  therapy,  average  patient  days  on  02,  average  patic 
x>st   total  %  of  weaning  that  occurred,  and  documented  adverse  outcomes.  Resu 

it 

•>g 

lo 
lard 

ed 

32 

3 

nl 
Its: 

ng 

>y 

166 

Pre-Protocol 

Post -Protocol    C-0<05) 

■  Sp02  dacha 

139 

,<6 

i  Sp02  ch*du>  95% 

122 

106 

ICCdtOMBM 

3 

33- 

f  02  Increuea 

1 

11- 

Av.,.9.  »y>  or,  OS 

24 

12- 

Avsr&ge  pabent  charges 

1576  00 

t2gs.no- 

V.  o(  weaning  lor  Sp02>95% 

2% 

S1V 

Adverse  ouiccm.s 

0 

o 

conclusion:  1    Hnor  lo  prolocol  implementation,  a  negligible  amount  ol  V2  wean 
rvas  performed  by  the  RN/RT  stall    2   The  protocol  appears  to  be  safe  without  a 
adverse  outcomes  noted   3  The  Pediatric  Oxygen  Weaning  Protocol  has 
ubstantially  reduced  both  oxygen  administration  and  patient  cost. 

OF-95 

THE  EFFECT  OF  RCP  DETERMINATION  OF  DEVICE.  DOSE, 

FREQUENCY  AND  PATIENT  SELF  ADMINISTRATION  OF 

MEDICATED  AEROSOLS 

J.  Fink.  MS,  RRT,  Ruth  Lyles,  RRT,  E.  Haggerty,  RN, 

E.  Belingon,  RRT,  P.J.  Fahey,  MD    Hines  VA  Hospital.  Hines  IL. 

In  1 993,  only  70%  of  ordered  aerosol  treatments  were  completed  on 
acute  care  floors,  with  >  95%  administered  by  small  volume  nebulizer 
(SVN)  in  the  hospital,  although  >  90%  of  the  patients  used  metered-dose 
inhalers  (MDI)  at  home,  often  with  inadequate  instruction  in  their  use. 
Patient  satisfaction  surveys  rated  respiratory  care  below  the  50th 
percentile.  Guidelines  for  dosage  and  substitution  of  specific  drugs  for 
MDI,  SVN  and  Mechanical  Ventilator  administration  were  incorporated 
in  a  multidisciplinary  hospital  wide  policy  with  Nursing,  Medicine. 
Surgery,  Pharmacy  and  Respiratory  Care  Services  by  which    RCPs 
determine  appropriate  aerosol  device,  titrate  bronchodilators  to  response 
and  adjust  frequency  of  administration.   RCP  also  instructs  patient  in  self 
administration  when  dose  and  frequency  are  at  standard  levels.   By 
April  1994,  the  policy  was  fully  implemented,  with  98%  of  patients 
receiving  MDI  with  holding  chamber,  and  99%  of  ordered  treatments 
accomplished,  reducing  workload  by  5  FTE  (allowing  a  full  time  RCP  to 
be  assigned  to  outpatient  clinics).  While  total  number  of  aerosol 
treatments  remained  stable,  hours  of  direct  patient  contact  was  reduced 
by  45%.   Savings  of  >  $78,000/year  based  on  reduced  time  per 
treatment  with  MDI  and  RCPs  training  patients  to  competently  self 
administer  therapy  in  the  hospital.  After  the  first  year,  the  Press-Ganey 
report  of  patient  satisfaction  for  our  hospital  identified  Respiratory  Care 
Services  to  be  in  the  top  96th  percentile  of  positive  responses. 

We  conclude  that  when  RCPs  are  empowered  by  the  medical 
staff  to  determine  device,  dose  and  frequency  of  aerosolized 
medication,  with  an  emphasis  on  patient  education  and  clinical 
response,  patient  satisfaction  is  improved  and  hospital  costs  are 
reduced. 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1161 


Saturday,  December  2,  3:00-4:55  pm  (Rooms  230C-D) 


EFFECTIVENESS  OF  A  PROTOCOL  FOR  METERED  DOSE  [NHALER  WITH  SPACER 
DELIVERY  OF  ALBUTEROL  FOR  PEDIATRIC  PATIENTS  HOSPITALIZED  WITH 
ACUTE  ASTHMA  Michael  Anders.  RRT.  Sarah  Scholle.  DtPH,  Kim  Kellogg,  MBA,  Sarah 
Shcma,  MS.  and  Deborah  Fawcrtt  MD  Arkansas  Children's  Hospital,  Little  Rock,  AR.  An 
asthma  care  plan  (ACP),  which  includes  a  protocol  for  delivery  of  albuterol  via  metered  dose 
inhaler  with  spacer  (MDI).  was  implemented  at  our  institution  Pediatric  patients  admitted  for 
acute  exacerbation  of  asthma  outside  of  the  P1CU  are  entered  into  the  ACP  Frequency  and 
dose  of  albuterol  are  determined  by  a  clinical  score  that  is  assessed  by  a  respiratory  care 
coordinator  every  six  hours  When  clinical  score  reflects  a  high  level  of  seventy,  albuterol  MDI 
frequency  is  every  two  hours  and  dose  approximates  one-third  of  the  dose  formerly  given  with 
intermittent  jet  nebulization  delivery   With  improvement  in  clinical  score,  frequency  and  dose 
are  reduced  If  a  deterioration  in  cluneal  score  occurs,  physicians  are  contacted  for  adjustment 
of  the  care  plan  The  effectiveness  of  utilizing  MDI  with  spacer  in  the  ACP  was  evaluated 
METHODS  Standardized  data  collection  from  retrospective  chart  review  and  Hospital 
Information  System  was  performed  for  children  admitted  with  a  primary  diagnosis  of  asthma 
from  Aug.  1  -  Oct.  3 1  in  1 993  (Control  Group  N=85)  and  1 994  (ACP  Group  N=67)  We 
excluded  patients  admitted  or  transferred  to  PICU,  admitted  to  both  groups  or  readmitted  within 
the  same  group,  and  patients  for  whom  charts  were  unavailable  Differences  between  the  1993 
control  group  and  the  1 994  ACP  group  were  analyzed  using  the  chi-square  test  for  categorical 
variables  and  /  test  to  compare  means  An  exact  test  for  trend  was  used  to  examine  differences 
in  length  of  stay  (LOS)  between  groups  RESULTS:  Co-morbidity  and  demographic 
characteristics  were  similar  between  the  two  groups.  There  was  a  significant  increase  (p  <.05) 
in  the  percentage  of  Medicaid  patients  in  the  ACP  group  The  percentage  of  patients  with 
previous  hospitalizations  was  nearly  equal  between  the  groups  However,  the  percentage  of 
patients  presenting  with  prior  emergency  department  (ED)  visits  was  significantly  increased 
(p<_05)  in  the  ACP  group  There  was  no  difference  in  the  mean  pulse  oximetry  measurement  at 
the  time  of  initial  evaluation  in  the  ED,  or  average  number  of  hours  in  the  ED  LOS  trended 
downward  in  the  ACP  group  (mean:  1993=  2  1  days.  1994=  1  8  days),  including  a  decrease  in 
the  percentage  of  patients  with  a  LOS  >  3  days  (1993=  27%.  1994  =  15%).  Albuterol  aerosol 


delivery  method. 


ity.  and  tuning  data  are  as  follows: 
MDI  with  spacer 


1993 

35% 


1994 
100% 


Mean  no  of  treatments  10.9  10  9 

within  6  hours  of  admission  1.6  2  0 

within  12  hours  of  admission  3.0  3  8 

within  24  hours  of  admission  5.3  6.9 

CONCLUSIONS  The  inability  lo  compare  seventy  between  groups  is  a  limitation  of  this 
study  However,  the  ACP  group  included  a  larger  proportion  of  patients  on  Medicaid  and  with 
prior  ED  visits,  factors  consistent  with  increased  LOS  and  uncontrolled  asthma  MDI  in  the 
ACP  was  used  for  treatment  of  acute  exacerbation  of  asthma  without  apparent  adverse  effect  oi 
pediatric  patients  Overall,  MDI  is  a  more  time- beneficial  form  of  aerosol  delivery  compared  tc 
jet  nebulization,  particularly  when  dose  is  reduced  as  clinical  condition  improves  Therefore, 
the  ACP  protocol  for  MDI  delivery  of  albuterol  in  pediatric  patients  has  important  implications 
for  resource  utilization  Moreover,  because  children  with  asthma  frequently  use  MDI  at  home 
and  school,  inpatient  use  provides  an  opportunity  to  reinforce  patient  and  family  education 


EARLY  EXPERIENCE  WITH  AN  APPROPRIATENESS  GUIDELINE 
FOR  SAMPLING  ARTERIAL  BLOOD  GASES  IN  AN  ICU    Perez- 
Trepichio  P  BS.  RRT.  Stoller  J  K  MD  Cleveland  Clinic  Foundation, 
Cleveland,  Ohio 

Available  studies  suggest  that  over-ordenng  of  arterial  blood  gases  (ABGs) 
occurs  commonly  in  Intensive  Care  Units  and  can  be  lessened  by  implementing 
guidelines  for  appropriate  ABG  sampling  To  assess  the  appropriateness  of 
current  ABG  sampling  in  our  Medical  Intensive  Care  Unit  and  as  a  possible 
basis  for  implementing  future  guidelines,  we  undertook  this  retrospective 
audit  Using  AARC  Clinical  Practice  Guidelines  and  published  protocols  for 
ABG  sampling  an  algorithm  was  drafted  and  applied  to  100  ABGs  drawn 
from  13  randomly  selected  adult  Medical  Intensive  Care  Unit  patients  on 
mechanical  ventilation  (mean  7  7  ABGs/patient,  range  5  to  12)  Reasons  for 
needing  ICU  care  included  respiratory  failure  (46%  [n=6]),  ARDS  (23% 
[n=3]),  pneumonia  ( 1 5%  [n=2]),  COPD  (8%  [n=l])  and  CHF  (8%  [n=I]) 
Indwelling  arterial  lines  and  continuous  pulse  oximetry  were  used  in  all 
patients  Conclusions  regarding  the  appropriateness  of  sampling  ABGs  were 
made  by  a  single  observer  (PP-T)  based  on  retrospective  review  of  medical 
records  Of  the  100  ABGs  reviewed,  56%  did  not  satisfy  appropriateness 
criteria  according  to  the  algorithm  Seventy  five  per  cent  of  these  56  ABGs 
did  not  prompt  any  adjustment  of  the  mechanical  ventilator  or  of  the  inspired 
oxygen  concentration  All  13  patients  underwent  at  least  one  ABG  sample  that 
was  not  deemed  indicated  Furthermore,  in  2  patients  (3  occurrences),  the 
algorithm  called  for  an  ABG  sample  that  was  not  obtained  The  results  of  this 
preliminary  retrospective  audit  suggest  that    I    As  in  other  series,  over- 
ordenng  of  arterial  blood  gases  occurs  commonly  in  our  Medical  Intensive 
Care  Unit,  2  Under-ordenng  of  ABGs  is  also  observed,  but  occurs  less 
commonly,  3  Blood  gases  that  were  drawn  inappropriately  frequently  failed 
to  prompt  any  adjustment  of  therapy  to  improve  oxygenation  or  ventilation,  4 
Further  research  should  assess  features  of  patients  and  caregivers  that 
accompany  over-ordenng  and  strategies  to  improve  the  allocation  of  ABG 
sampling  in  the  intensive  care  unit 


Laura  N  Kanov,  BS.RRT,  Respiratory  Care  Director, Robert  Zeck,  MD,  Medical  Director 
for  Respiratory  CareHmsdate  Hosprtal.120 N  Oak  St  .Hinsdale.  IL  60521 

BACKGROUND  Forces  determining  ihe  future  of  health  care  mandate  lower  costs  while 
maintaining  quality  outcomes  This  study  examines  the  effects  of  a  therapist-driven  bronchial 
hygiene  program  on  the  charges,  lengths  of  stay.  ICU  days  and  complications  in  patients 
undergoing  cardiac  surgery  METHODS  Evaluations  were  done  preoperative!  y  (excluding 
patients  proceeding  directly  to  surgery  from  the  cath  labjto  determine  pre-op  diagnostic  needs 
Patient  education  was  done  at  this  time  and  an  incentive  spirometry  goal  was  established  as  well 
Patents  were  seen  post-op  as  soon  as  hemodynamically  stable  to  determine  bronchial  hygiene 
needs  and  followed  up  each  subsequent  shift  Needs  were  determined  using  a  flow  diagram 
which  assessed  indicators  such  as  atelectasis,  vital  capacity  and  secretion  production  All  parts  of 
the  evaluation  and  educational  process  were  performed  by  specially  trained  therapists,  while 
respiratory  modalities  could  be  performed  by  any  staff  member  STUOYDESGN  We  evaluated  all 
patients  undergoing  surgery  for  CABG  or  Valve  Repair/Replacement  over  a  three  month  period 
(80  in  total)  We  compared  charges,  length  of  stay,  ICU  days  and  complications  to  (all)  65  patients 
in  the  3  month  penod  immediately  preceding  the  pilot  study  and  (all)  99  patients  in  the  same  3 
month  period  of  the  previous  year  Data  were  evaluated  retrospectively  to  determine  the 
mathematical  means  and  were  compared  An  ANOVA  was  used  for  further  analysis  RESULTS 
Patients  in  the  pilot  group  had  lower  mean  hospital  charges,  respiratory  charges,  length  of  stay  , 
and  ICU  days  White  comorbidities  were  slightjy  more  prevalent  in  the  pilot  group,  no  significant 
difference  existed  in  complications  among  the  groups  Patents  with  chronic  lung  disease  showed 
the  most  improvement  over  the  control  groups  including  decreased  incidence  of  pneumonia  ■ 
15.4%  in  the  pilot  group  compared  to  54.5%  in  control  1  and  37.5%  in  control  2  CONCLUSION: 
Although  ANOVA  indicated  no  statistically  significant  differences  among  the  groups,  our  results 
suggest  that  a  bronchial  hygiene  program  dnven  by  specially  trained  therapists,  which  includes 
patient  education,  is  associated  with  reduced  respiratory  and  hospital  charges,  decreased 
lengths  of  stay  and  ICU  days  in  patients  having  major  cardiac  surgeries,  particularly  in  patients 
with  chronic  lung  disease 

Mean  Value*  -  All  Pat  entt 


Group 

„ 

Hosp  $ 

Resp  $ 

ABG$ 

LOS 

ICU  Days 

Pilot 

BO 

$72569 

$3,592 

$4611 

11.4 

50 

Control  1 

65 

$88424 

$4,783 

$6  142 

13.4 

6.6 

Control  2 

99 

$88,223 

$5,842 

$3,510 

13.9 

62 

ANOVA 

p=0  26 

p=0  26 

p=0  00 

p=0  36 

p=0  46 

Moan  Valuos  - 

Patient*  with  Chronic  Lung  Disease 

Group 

n 

HospS 

Rer.p  S 

ABG$ 

LOS 

ICU  Days 

Pilot 

13 

$70,63? 

$4,847 

$4,384 

118 

49 

Control  1 

11 

$169,336 

$13,963 

$11,029 

28  1 

159 

Control  2 

8 

$187,942 

$18,977 

$4,912 

26  0 

186 

ANOVA 

p=0  09 

p=0  23 

p   001 

p=0  09 

p=0  09 

FACE  TO  FACE 
WITH  CHANGE 


AARC  41st  Annual  Convention 
&  Exhibition 

Orlando,  Florida 
December  2-5,  1995 


Pie-registration  deadline 
November  11,  1995 

On-site  registration 

10  am,  December  1,  1995 

at  the  Orange  County  Convention  Center 

For  information,  eall  (214)  243-2272 


162 


Respiratory  Care  •  novi-:mm-;r  "95  voi.  40  No  1 1 


Sunday,  December  3,  12:45-2:40  pm  (Rooms  230A-B) 


Donna  teihoff  B5,  HI,  CFFT;  Cone  S tens rt- Sock  ley  BS,  HHT;  Anthooy  Vacca 


lissDs::  Hospital  and  CI i: 


:j:::> 


PJTIEIT  31fi  AID  CASE  SUHSiST:  «  present  two  cases  of  patients  ia  which  the  pressures 
generated  by  their  cardiac  contractions  were  significant  enough  to  tnggei  the 
ventilators,  causing  a  respiratory  alkalosis.  Both  patients  were  ventilated  uith  a  Sieiens 
Servo  900C.  Patient  A  was  a  57  yr  old  with  pneuioma  and  respiratory  failure.  Ventilator 
settings  me  VC,  TV  700,  BR  12,  Fi02  .40,  PeeP  5,  sensitivity  -1  CiP.  Initial  ABGs 
without  patient  assisting  were  7.42/32/95.  The  neit  routine  AM  ABG  reported  7.63/18/^4 
with  7estilitor  being  triggered  at  a  rate  of  IS.  The  physician  requested  decreasing  IV  to 
oSGcc.  ABGs  were  then  7.52/27/109  with  the  ventilator  still  being  triggered  at  16.  So 
apparent  efforts  were  being  generated  by  the  patient,  and  closer  observation  noted 
deflection  of  the  pressure  aanoieter  needle  consistently  with  every  heart  beat,  creating 
enough  negative  pressure  to  trigger  the  ventilator.  Siiuitaneous  recordings  of  :CG  and 
airway  pressure  tracings  were  taken.  This  trss  accomplished  by  placing  an  adaptor  into  the 
ventilatcr  circuit  at  the  patient  wye  and  connecting  to  it  an  air  filled  arterial  line 
tubing  with  a  transducer  that  was  then  connected  to  the  ECC  aonitcr.  This  allowed  printed 
strips  shosiag  ventilator  trigger  consistent  with  cardiac  contraction.  To  prevent  the 
heart  beat  froa  triggering  the  veotilator,  sensitivity  was  decreased  to  -2  CMP.  ASC's 
returned  to  7.42/35/107.  Patient  B  was  a  64  yr  old  aale  with  Sit  and  a  prolonged  history 
of  iasunosuppression  with  corticosteroids  resulting  in  PCP.  This  patient  required 
paralysis  to  aaintain  optinal  oxygenation  on  settings  of  PC  30,  flR  20,  FiC2  .85,  Peep  13, 
sensitivity  -2  CiP.  Patient  assisting  the  ventilator  was  noted.  However,  in  the  assessaent 
fo:  need  of  acre  neuromuscular  blockade,  it  was  detected  that  the  heart  beat  was  the 
triggering  aechanisa  resulting  in  ABGs  of  7.53/21/94.  Siaultaneous  ECG  and  airway  pressure 
tracings  sere  recorded  as  described  with  patient  A.  The  tracing  below  shows  that  with 
decreasing  the  sensitivity  to  -3  CUP,  the  heart  beat  triggering  ns  ehainated  and  ABC's 
revealed  7,43/32/106. 
SIGBIFICAJCE  Literature  survey  revealed  nothing  as  reported  here  regarding  the  heart 

ventilator.  Uheo  ruling  out  reasons  that  ventilated  patients  aaintain  a  respiratory 

alkalosis  {pain,  agitation,  anxiety,  sepsis,  etc,!  heart  beat  triggering  can  be  added  to 
the  list.  He  have  subsequent;;  seen  further  casts  of  this  both  sith  th:  9C0C  and  the  Bear 


MUI  SSPRI  1)11  lOKMokl'ASSY-MtHKNPl  AMNIi  V,\l  V}  HSI  IN  A.  PIDIA  I  RK 
POPULATION  A  METHOD  EVALUATION  Liz  B  Trotter.  B  S  .  R.R.T  .  C  P  FT  .  Perinatal 
Pediatric  Specialist    l"hc  Children-.  Seashore  House   Philadelphia.  PA 

INTRODUCTION  After  discussing  the  anatomy  and  flow  dynamics  of  pediatric  tracheas  with 
two  pediatric  critical  care  physicians,  il  was  hypothesized  that  an  audibly  measured  leak  of  1 5 
centimeters  of  water  pressure  (eniH20)  or  less  and/or  an  electronically  measured  leak  of  50%  or 
greater  should  predict  successful  use  of  the  Passv-Muir  \  a  he    I  his  size  gas  leak  should  support 
sufficient  gas  passage  around  the  tube  without  producing  c\cessi\c  PI  LP   Toe  Passy-Muir 
Spcaking  Valve  is  a  one  way  valve  intended  for  use  with  tracbeoslomized  patients  of  all  age 
groups  to  improve  speech   Speech  pathologists  have  incorporaled  use  of  the  \arve  tn  their 
treatment  plans  tor  patients  with  swallowing  discoordinalion    A  rnelhod  to  predict  successful  use 
of  the  speaking  valve  was  needed  to  prevent  patient  lear  distress  and  trauma,  and  future  non- 
compliance METHOD    Six  non -mechanically  ventilated  traeheostomized  patterns  between  sl\ 
months  and  five  years  of  age  were  studied  Sample  size  was  limited  by  our  institution's  total 
number  of  traeheostomized  children  who  were  not  mechanically  ventilated  The  gas  leak  around 
each  patients  tracheostomy  tube  was  evaluated  audibly  with  a  flow-inflating  resuscitation  bag  with 
an  in-line  pressure  manometer  Electronic  evaluation  of  the  tube  leak  was  performed  in 
accordance  with  the  Bear  Neonatal  Volume  Monitor  I  Iscr  Manual  and  results  were  reported  as  a 
percentage  (expired  tidal  volume/inspired  tidal  voluine=%  leak)  Audible  evaluation  with  the 
resuscitation  bag  was  achieved  by  placing  a  stethoscope  over  each  patient's  trachea  while 
gradually  tightening  the  resuscitation  bag  vahe  to  achieve  increasingly  higher  airway  pressures 
The  pressure  at  which  the  leak  was  heard  was  recorded  in  cml  12(1    Patients  with  audibly  measured 
leaks  of  15  cmll20or  less  and/or  an  electronically  measured  leak  of  5tr%or  greater  were 
hypothesized  to  have  a  high  probability  of  success  with  the  Passy-Muir  Vahe   This  hypothesis 
was  tested  via  institution  of  the  valve  RESirLTS/KXPKRIENCH  Successful  outcomes  were 
predicted  in  all  sr\  cases  when  the  patients'  measured  parameters  positively  correlated  with  the 
defined  criteria  for  predicting  success  or  failure  <  Mher  moniinnng  sv  stems,  such  as  end-tidal  C02 
and  Sp02  were  initially  used  to  evaluate  patient  response  Monitoring  Sptl2  was  abandoned 
because  patients  often  failed  acutely  before  a  desaturation  could  be  measured     These  patients  were 
often  agitated  and  immeasurable  using  oximetry    Ind-tidal  C02  was  only  minimally  acceptable 
and  was  used  secondarily  as  a  confirmation  of  success    Select  patients  with  established  language 
skills  were  tested  with  a  speech  pathologist  present   These  patients  needed  reassurance  and 
coaching  to  attempt  verbalization    The  session  was  disrupted  when  the  end-tidal  monitor  was 
placed  in  the  patient's  mouth  CONCLUSION   Identification  of  potential  success  with  leak 
measurements  is  a  valuable  tool  when  instituting  the  Pass-y  -Muir  Valve    Potential  for  patient 
distress  and  harm  is  greatly  reduced  and  patient  trust  i>  protected    Although  this  study  reflects 
only  non-mecbanically  ventilated  patients  mechanically  ventilated  patient-,  could  be  studied  m  a 
similar  fashion  A  substantial  leak  is  necessary  for  use  of  the  Passv-Muir  Valve  with  a  ventilator, 
because  all  exhalation  occurs  around  the  tube  through  the  patient's  natural  airway    Passy-Muir. 
I  ik   recommends  the  tracheal  tube  only  occupy  one  third  of  the  tracheal  lumen  when  used  with  a 
mechanical  ventilator    A  non-invaM\c  assessment  o|  tube  size  would  enable  the  practihoner  to  be 
confident  in  use  of  the  Passy-Muir  Valve  in  both  ventilated  and  non-ventilated  palienl  populations 


HEPATIZATION  OF  A  LUNG  LOBE  AS  A  CAUSE  OF  PERSISTENT 
COUGH.  Ali  Emad  MP.  Shiraz  University  of  Medical  Sciences, 
Shiraz,  Iran. 

BACKGROUND:  Hepatization  of  a  lung  lobe  is  rare.  I  report  a 
case  of  hepatization  of  the  right  lower  lobe  resulting  in 
severe  paroxysmal  cough.  CASE  SUMMARY:  A  28-year-old 
man  who  sustained  a  gunshot  injury  8  years  ago  with 
resultant  perforated  right  hemidiaphragm  and  lacerated  liver 
now  complained  of  paroxysmal  cough.  Shortly  after  these 
were  repaired,  the  patient  complained  of  gradually  worsening 
dyspnea  on  exertion.  A  chest  radiograph  (CXR)  revealed 
elevation  of  the  diaphragm  and  pleural  effusion  on  the  right. 
Surgery  revealed  herniation  of  the  liver  through  the 
diaphragm,  which  was  repaired.  Three  weeks  after  surgery, 
patient  developed  a  chronic  cough  that  persisted  and,  now, 
has  become  paroxysmal.  Each  CXR  has  shown  elevated 
diaphragm  that  was  believed  due  to  sluggish  movement  of  the 
diaphragm.  Right-basilar  breath  sounds  were  decreased.  In 
addition  to  the  elevated  diaphragm,  CXR  showed  narrowing  of 
the  right  middle  and  lower  lobes.  Bronchography  supported  the 
diagnosis  of  hepatization  of  these  lobes.  Thoracotomy 
revealed  that  the  lower  lobe  was  attached  to  the  diaphragm. 
Both  middle  and  lower  lobes  were  resected  and  the  diagnosis 
was  confirmed  by  histology.  Six  months  after  this  operation, 
the  patient  is  well.  DISCUSSION:  Hepatization  means  a 
transformation  of  a  lesion  into  a  liver-like  mass  during  a 
process  of  pneumonitis,  which  is  transient.  The  hepatized  lung 
tissue  cannot  participated  in  gas  exchange.  This  condition  is 
rare  but  may  be  found  following  pneumonia,  lung 
transplantation,  migration  of  Ascaris  larvae,  poisoning,  and 
trauma.  Symptoms  are  variable  and  include  persistent  and 
paroxysmal  cough,  hemoptysis,  repeated  pneumonia,  hypoxia 
and  chest  pain.  The  diagnosis  is  made  by  biopsy.  Persistent 
hepatization  of  a  lung  lobe  should  be  considered  as  a  cause  of 
an  unresolved  and  undiagnosed  cough  following  diaphragmatic 
trauma. 


Intermittent    Regular    Treatment    of    Moderate    to    Severe 
Asthma    with    Theophylline     Is     Beneficial.  Ali  Emad  MP. 
Shiraz  University  of  Medical  Sciences,   Shiraz, Iran. 
BACKGROUND:   Asthma  is  a  chronic  inflammation  of  the  lower 
airways  that  can  be  severe  and  even  fatal.  I  studied    1 20 
patients  with  moderate  to  severe  asthma  (defined  by  the  ATS) 
to  test  whether  the  addition  of  regular  intermittent 
theophylline  to  a  regimen  of  beclomethasone  and  b-2   agonist 
would  significantly  affect   FEVi,  PEFR  and  rate  of  hospital 
admission.   METHODS:  Subjects  of  both  genders,  aged  1  8  to  60 
yearswere  randomized  to  1  of  3  groups  each  with  n  =  40.  Group 
1  was  given  inhaled  beclomethasone  (500  mg  daily)  and  short- 
acting  inhaled  6-2  agonists  as  needed  3-4  times/day.  Group  2 
received  drugs  as  Group  1  and  a  placebo.  Group  3  received  drugs 
as  Groups  1  and  2  and  theophylline  (250  mg  qod,  hs).  FEVi  and 
PEFR  was  measured  on  all  patients  before  and  after  study  and 
the  number  of  hospital  admissions  due  to  severe  attacks  of 
asthma  during  the  previous  6  months  and  after  the  study  were 
calculated.   RESULTS:  Mean  (SD)  FEVi  and  PEFR  at  the 
beginning  of  the  study  were  1 .35  ±  0.025  L  and  3.02  ±  0.078 
L/s,  Group  1 ;  1 .32  ±  0.034  L  and  2.91  ±  0.085  L/s.  Group  2;  and 
1.31±  0.035  L  and  2.87  ±  0.087  L/s,  Group  3.  After  6  months 
these  values  were  1.51  ±  0.039  L  and  3.29  ±  0.064  L/s,  Group  1; 
1.49  ±0.035  Land  3.12  ±0.064  L/s,  Group  2;  and  1.82  ±0.028  L 
and  4.06  ±  0.093L/S,  Group  3.  The  values  for  both  these 
variables  were  significantly  improved  after  study  (ANCOVA,  p 
=  0.001).  Total  numbers  of  hospital  admissions  before  vs  after 
the  study  were  17  vs  14,  20  vs  18,  and  1  2  vs  4  for  Groups  1,  2, 
and  3,  respectively.  No  significant  difference  in  total  number 
of  the  hospital  admissions  among  the  3  groups  was  found  prior 
to  study  (ANCOVA,  p  =  0.188).  After  the  study,  Group  3's 
hospital  admissions  significantly  declined  compared  to  Groups 
1  and  2  (ANCOVA,  p  =  0.001  7).  CONCLUSIONS:    Intermittent 
regular  use  of  theophylline  may  benefit  patients  with 
moderate  to  severe  chronic  asthma. 

OF-95-057 


Respiratory  Care  •  November  '95  Vol  40  No  11 


163 


Sunday,  December  3,  12:45-2:40  pm  (Rooms  230A-B) 


ADAPTOR  AP-2,  A  COATED  PIT  PROTEIN  COMPLEX,  IS 
REQUIRED  FOR  ALVEOLAR  MACROPHAGE  PHAGOCYTOSIS 
Douglas  G.  Perry,  PhD,  RRT,  and  Gena  Daugherty,  BS 

Respiratory  Therapy  Program,  School  of  Allied  Health  Sciences, 
and  Division  of  Pulmonary  and  Critical  Care  Medicine, 
Indiana  University  School  of  Medicine,  Indianapolis  IN  46202. 

Introduction:  Clathrin-coated  pits  (CCPs)  are  found  on  the  cytoplas- 
mic membrane  surface  of  alveolar  macrophages  (AMs).  CCPs  are  in- 
volved in  receptor/membrane  recycling  during  cell  migration  and  may 
also  play  a  role  in  phagocytosis.  We  previously  demonstrated  that 
clathrin  is  directly  involved  in  phagocytosis  (Perry  DG  and  Martin  WJ, 
1994:  Am  J  Resp  Crit  Care  Med  149:A238).  To  determine  whether 
another  CCP  component,  adaptor  AP-2,  is  expressed  by  AMs,  we  lo- 
calized AP-2  by  immunocytochemistry.  To  test  whether  AP-2  is  also  in- 
volved in  phagocytosis,  we  inhibited  AP-2  activity  using  liposomes  to 
deliver  anti-AP-2  monoclonal  antibody  (mAb)  to  rat  AMs  and  mea- 
sured subsequent  phagocytic  activity  by  fluorometry.  Methods:  Rat 
AMs  were  obtained  by  lavage,  fixed  in  4%  paraformaldehyde,  permea- 
bilized  with  0.1%  Triton,  incubated  with  1 :40  anti-AP-2  mAb,  rinsed, 
and  incubated  with  1 :100  FITC-lgG.  Control  cells  did  not  receive  anti- 
AP-2  mAb.  Liposomes  were  prepared  by  aqueous  reconstitution  with 
1 :40  anti-AP-2  mAb;  control  liposomes  contained  nonspecific  antibody. 
AMs  labeled  with  the  fluorophore  Dil  were  incubated  with  the  lipo- 
somes, then  challenged  for  phagocytosis  with  fluorescent  liposomes. 
Phagocytosis  was  measured  with  a  dual-beam  fluorometer.  Results: 
AP-2  is  present  in  rat  AMs,  with  distnbution  largely  limited  to  the  cell 
membrane,  where  clathrin-mediated  retrieval  of  surface  receptors  oc- 
curs. AMs  treated  with  anti-AP-2  liposomes 
had  significantly  lower  phagocytosis  than 
control  cells  (4.81  ±  0.23  vs.  9.54  t  0.76 
liposomes/cell,  respectively;  p<0.001). 
Conclusion:  These  findings  further  support 
the  hypothesis  that  CCPs  are  directly  in- 
volved in  phagocytosis.  Supported  in  full  by 
"NIH  grant  HL50128  (D.G.P.). 

OF-95-069 


I. 

ill: 


SUCCESSFUL  INDEPENDENT  LUNG  VENTILATION  DN  A  ONE-YEAR  OLD  Dunnda 
Mulluis.BA.RRT.  Anna  August,  MD.  George  B  MalJory.  Jr,  MD,  James  S  Kemp.  MD  Si 
Louis  Children's  Hospital,  Si  Louis.  MO 

Independent  lung  ventilation  (TLV)  has  been  used  to  ventilate  Bdull  and  pediatric  patients  with 

unilateral  lung  disease  who  were  failing  conventional  mechanical  venulation  (CMV).  We  report 
the  use  of  IL V  in  a  one  year  old  with  chronic  obstructive  pulmonary  disease 

The  patient,  a  28  week  gestation  twin  born  by  emergency  Caesarian  secuon  for  placentaJ  abruption, 
was  transferred  to  our  institution  at  one  year  of  age  for  lung  transplant  evaluation    His  medical  his- 
tory included  bronchopulmonary  dysplasia  with  ventilator  dependency,  herniation  of  the  right  lung 
into  the  left  hemilhorax  at  age  7  months,  left  lung  atelectasis  of  unclear  etiology  at  age  9  months, 
tracheomalacia,  right  ventricular  hypertrophy/cor  pulmonale,  systemic  hypertension,  and  question- 
able life- threatening  events  of  unclear  origin  requiring  cardiopulmonary  resuscitation    At  admission, 
he  was  mechanically  ventilated  in  SDMV  mode,  rate  46,  tidal  volume  (TV)  90  cc,  50%  FiOj,  and  +3 
PEEP  with  a  representative  arterial  blood  gas  (ABG)  of  pH  7  38,  PCO,  72.  PO,  53     At  our  insti- 
tution, chest  CT  showed  a  markedly  hypennflaied  right  lower  lobe  extending  across  the  midline  with 
ateleclauc  nght  upper  and  right  middle  lobes,  atelectatic  left  lung,  and  mediastinal  shift  to  the  left 
The  patient  was  bronchoscoped  3  tunes  in  five  days,  bronchoscopy  revealed  severe  tracheomalacia 
with  total  tracheal  collapse  1  -2  cm  above  the  carina    During  each  bronchoscopy,  large  amounts  of 
yellow  secretions  were  suctioned  from  the  left  lung    Post- bronchoscopy  chest  x  rays  (CXR)  showed 
increased  aeration  of  the  left  lung,  but  within  12-18  hours  after  each  bronc  oscopy  the  left  lung  again 
became  atelectatic    The  decision  was  made  to  try  ILV  to  bypass  the  area  of  tracheomalacia  and 
reinflale  the  left  lung    The  patient  was  reuitubated  with  2  endotracheal  rubes  using  an  ultra-thin 
bronchoscope  One  tube  was  passed  through  the  tracheostomy  site  into  the  nght  mainstem  bronchus, 
the  other  was  passed  nasally  into  the  left  mainstem  bronchus    Right  lung  settings  were  SIMV  mode 
rate  1 5.  TV  50cc,  60%FiO„  +2  PEEP,  Insp  time  3  sec,  left  lung  settings  weTe  SDMV  mode  rate  30. 
TV  70cc.  60%  FiOj.  +6  PEEP.  Insp  time  5  sec    ABG  one  hour  after  instituting  IX V    pH7  44. 
PCO,  60.  PO,  6 1    CXR  showed  increased  aeration  of  the  left  lung  with  decreased  hyperinflation  of 
the  nght  lung    Pulmonary  function  tests  on  day  3  of  ILV  showed  the  following 


Parameter 

FRC  (cc) 

Compliance  (cc/cwp) 
Tunc  constant    (sec) 


R;sh'  Imu 


3  23 


Left  Lung 


I  04 


The  patient  was  maintained  on  ILV  with  no  change  in  ventilator  settings  for  7  days,  last  ABG  was 
pH  7  4 1 ,  PCO,  53,  PO,  65     On  day  8  of  ILV  the  two  endotracheal  tubes  were  removed  and  the 
patient  wu  reuitubated  with  a  tracheostomy  tube  end  ventilated  at  SIMV  mode  rale  40.  TV  90cc, 
60%FiO„+3PEEP    ABG  after  discontinuance  of  ILV    pH  7  42,  PCO,  51.  PO,  61    CXR  showed 
nearly  symmctnc  lung  expansion    Over  the  next  8  days,  ventilator  support  was  decreased  to  SIMV 
rate  30.  TV  90cc,  FiO,  40%.  and  +3  PEEP  with  a  representative  ABG  of  pH  7  40.  PCO,  55.  P02 
65    The  left  lung  remained  inflated  on  alt  CXRs  after  the  discontinuance  of  D_V     On  the  ninth  day 
after  discontinuing  ILV,  the  patient  expenenced  ventricular  tachycardia  rapidly  progressing  to 
bradycardia  and  asystole  from  which  he  was  unable  to  be  resuscitated 

OF-95-091 


TEMPERATURE  LOSS  IN  DEADSPACE  EXPOSED  TO  AMBIENT 
B  Peterson  BE  Hon.  N  Rankin  MD,  D  Galler  MD    Intensive  Care  Unit,  Middlemore 
Hospital,  Auckland,  New  Zealand, 

Introduction  Delivery  of  heated  and  humidified  gases  to  mechanically  ventilated 
patients  is  essential  to  maintain  airway  integrity  Because  heated  humidifiers  typically 
use  a  temperature  probe  at  the  Y-piece,  we  sought  to  determine  the  temperature  drop 
from  the  site  of  measurement  to  the  teeth  in  mechanically  ventilated  patients  This  will 
suggest  the  appropnate  humidifier  settings  to  deliver  core  temperature  saturated  gases 
to  the  patient  Method  Gas  temperatures  were  monitored  in  the  breathing  circuit  of 
general  ICU  patients  during  mechanical  ventilation  A  Fisher  &  Paykel  MR730 
humidifier  with  heater  wire  circuit  was  controlled  at  various  temperatures  between  32 
and  39°C  in  a  25°C  ambient  Each  patient  had  approximately  6cm  of  endotracheal 
tube  (ETT)  protruding  from  the  teeth,  and  a  suction  port  with  10cm  of  flexible 
extension  placed  between  the  ETT  and  the  Y-piece  K  type  thermocouples  with  a  0.1 
second  response  time  measured  temperature  in  the  centre  of  the  tubing  at  three  sites 
1)  the  Y-piece,  2)  in  the  suction  port  between  the  flexible  extension  and  ETT.  3)  in  the 
ETT  just  pnor  to  the  teeth  (inserted  through  the  wall  of  the  ETT)  Results:  Temperature 
drops  were  recorded  over  both  the  flexible  extension  and  the  portion  of  ETT  protruding 
from  the  teeth  during  inspiration  and  expiration   Dunng  inspiration  temperature  drops 
of  up  to  4*C  from  the  temperature  setting  on  the  humidifier  to  the  teeth  were  recorded 
(See  figure  for  a  typical  breath)  Conclusions  The  magnitude  of  the  temperature  drop 
is  dependent  on  ambient  air  movement,  ambient  temperature,  tubing  geometry,  tubing 
lenglh,  and  flow  rate  Gases  undergo  a  significant  temperature  drop  in  the  unhealed 
tubing  between  the  Y-piece  and  the  patient  To  compensate  (or  this,  the  humidifier 
must  be  set  approximately  2'C  above  the  desired  gas  temperature 


Humidifier  Y-Piece  Temp    1  Temp  at  Teeth 

Temp   Drop 

38  0±0  5*C                      35  2±0  1"C 

2.8*C 

34  0±0S'C                      32  OtO  1X 

2.0'C 

Measurements  given  as  time  averages  for  ten  breaths,  ±2SD 

,,      Continuous  Mechanical  Ventilation  -  8  5Umin   10BPM. 


1164 


Rkspiratory  Cark  •  November  '95  Vol  40  No  1 1 


Sunday,  December  3,  12:45-2:40  pm  (Rooms  230A-B) 


ASSESSMENT  OF  ENDOTRACHEAL  TUBE  (ETTI  PLACEMENT  IN  NEONATES 
USING  A  FIBEROPTIC  STYLET 

Thomas  J  Kallslrom  R.R.T  and  Ruben  L-  Chalbum  R  R  T.  Rainbow  Babies  and  Children* 


Hospital,  Clc\cland,  OH 

This  is  a  continuation  of  a  pilot  sluJ\  (Rcspir  Care  1994*39;  1061 )  c\aluatin 

a  lighted 

riberoptic  atytet  (Infinit)  Fiberoptic  Sulci,  Fiberoptic  Medical  Products  Inc  i  lor 

assessment 

dI  ETT  placement  The  purpose  ol  the  stud\  was  to  determine  il  this  allcrnatnc  rt 

icthod  cou 

replace  routine  chest  \-ra>  (CXR)  assessment  METHOD:  Intubated  neonates  in 

ourNICU 

were  entered  into  the  stud\  over  a  one  year  penod  {convenience  sample)   Within 

(*)  minutes 

til  CXR  and  bclorc  the  results  were  known  to  the  KL'Han  bl  1  placement  cvalua 

on  was 

made  using  the  lighted  st\lct  The  lipol  the  st\lct  was  advanced  into  the  bl'l  to 

prc-mcasurcd  mart,  which  placed  it  al  ihc  distal  tip ol  the  tube  If  the  light  was  visible  through 
the  skin  at  the  suprasternal  notch,  the  ETT  was  considered  to  be  correctly  placed  II  the  light 
mis  visible  above  the  suprasternal  notch,  the  ETT  was  judged  to  be  loo  high  and  il  the  light 
disappeared  alicr  passing  below  the  notch,  the  ETT  was  judged  lobe  loo  tow,  The  pnvedure 
lasted  s  10  seconds  Sp02  was  measured  bclorc  and  alter  the  procedure  Assessment  ol  ETT 
placement  using  ihc  hbcroplic  stylet  was  evaluated  with  CXR  as  the  standard  (positive  and 
negative  predictive  values),  RESULTS:  Data  for 93  patients  were  collected  by  16  RCPs. 
Weight  range:  430-4100  grams;  ETT  si/c:  2.5-3 .5  mm  ID;  age:  1(1  minutes  to  2  months.  Fifty 
Caucasian.  37  were  not,  and  K  were  unknown     Data  analvsis  is  illustrated  in  the 


figure  below   SeVC 


82  o 

(X  B    -n 


:ighlci 


66 

11 

4 

12 

,of93(S4'X) 
negative  prcdi 


i  the  CXR  The  pus 


optic 


fliuewas754    Mean Sp02 bcfori 

identical    There  was  no  mdicatio 

j  RCPs  The  assessment  cm^- 


rcd  random!) 
.  Errors  in  ass 


<scd 


not  evident  The  average  weight  ol  cor 
infants  was  l,726g  vs  I573g  foi  the  group  incorrectly 
assessed,  ETT  si/c  distnbuUon  tor  correctly  assessed 
patients  was  2.5mm:  29%, 3.0mm:  50%, 3.5mm  21*  vs 
2  5mm:  24^.  3  (hnm  56%, 33mm:  18%  for  incorrectly  assessed  patients  EXPERIENCE 
The  lighted  stylet  is  a  portable  and  convenient  tool.  It  can  be  used  b>  the  RCP  without  the 
delay  that  wailing  tor  a  CXR  may  take  CONCLUSION:    The  stylel  docs  not  appear  to  be 
accurate  enough  at  determining  ETT  position  to  replace  CXR.  panicularl)  since  confirming 
proper  placement  is  not  as  desirable  as  identifying  improper  placement  No  clear  subset  ol  i 
population  could  be  identified  for  which  negative  predictive  value  was  acceptable  The 
resolution  of  assessment  seems  no  better  than  I  cm,  which  is  relative!}  large  compared  to  it 
length  ol  the  trachea  lor  this  population  ol  infants  This  observation  may  explain  our  lindinj 


IMPROVED  VERSATILITY  USING  NEW  CUFFED  TRACHEOSTOMY  TUBES  IN 
CHILDREN  ON  HOME  MECHANICAL  VENTILATION 

Ricnard  Francis  R.R  T.  Michelle  Howenstine  M  D  ,  David  Geller  M.D  ,  Kathy  Renn  R  N 
Division  of  Pediatric  Pulmonology,  Department  of  Respiratory  Care.  All  Children's 
Hospital.  St   PetersOurg,  Fl 


Hospital,  6  we 


■  patients  i 
night  Patients  complair 
low  energy  levels,   ar 


appropriate  alv 
The  patients  w> 
6  months  to  ev 

RESULTS    Of 
successfully 
improved  energy 
had   previously   t 


lese  patients  v 
;  performed  ev 


tube    The   results  demonstrated 
of  all  other  problems  the  patients 
every  6  months  reveal  no 
patients  were  deflated  during  the  day 
to  enhance  phonatton 

EXPERIENCE,  In  our  27  months  of  pediatric  experience  with  the  Bivona  TTS  tube  all 
patients  were  volume  ventilated  at  night  with  the  cuff  inflated  to  minimal  leak  volume. 
The  patients  were  managed  with  the  cuff  fully  deflated,  during  the  day  to  allow 
phanation  This  tuCe  proved  useful  in  patients  where  phonation  is  very  important  and 
uncuffed  tube  management  becomes  a  problem  Other  types  of  cuffed  trach  tubes  when 
deflated,  decrease  the  volume  allowed  to  leak  into  the  upper  resp  tract  and  limit 
phonation 


population  expands 


THE  EFFECT  OF  EXTERNAL  NASAL  OfWTON  ON  ATHLETIC  PERFORMNACE 
Mam  Jrocchio,  BS,  Anns  K  Parkman.  MBA.  BBI,  Jean  Fisher,  MBA,  RRT, 
University  of  Charleston,  Charleston,  WV 

Within  the  past  year,  many  athletes  have  begun  using  an  external  nasal 
dilator  (Breathe-Right  Nasal  Dilator,  CNS  Inc.,  ChanhassenlMN)  to  increase 
athletic  performance  Advertisements  claim  the  device  ™i  decrease  nasal 
congestion  and  improve  nasal  air  conductance  during  sleep.  The  athletes  have 
assumed  that  the  increase  in  nasal  airflow  will  improve  oxygenation  thereby 
elevating  performance  levels.  We  evaluated  the  effect  of  the  dilator  by  measuring 
changes  in  functional  capacity  (V02max)  and  Work  rate  during  controlled 
cardiopulmonary  exercise  testing  (MedGraphics  Cardio2,  Medical  Graphics 
Corporation,  St  PauIMN)  with  and  without  the  dilator.  Data  was  obtained  from  16 
male  college  atheletes.  Each  was  asked  to  exercise  maximally  (RER  >  1 .09) 
utilizing  identical  30  watt  ramped  cycle  ergometer  protocols  on  two  separate 
occasions  at  least  48  hrs  apart  with  and  without  the  nasal  dilator.  Trials  were 
randomized  to  eliminate  training  effect.  Mean  V02max  ■  3325  ml'min  (SD  ♦  520). 
Using  the  dilator,  mean  V02max  ■  3305  ml/min  (SD  ♦  5M)  for  a  mean  difference 
of  -21  ml'min  (SD  i  297).  Mean  peak  work- 291.1  watts  (SD +  37 .8).  With  the 
dilator,  mean  peak  work  ■  279.5  watts  (SD  ±  40.2)  reflecting  a  mean  difference  of 
•1 1 .46  watts  (SD  i  39.5).  No  significant  differences  were  observed  for  all  measured 
parameters  using  p><0.05  as  level  of  significance.  The  data  clearly  reflects  that 
use  of  the  dilator  during  exercise  elicits  no  demonstrable  change  upon  measured 
physiologic  parameters.  We  therefore  conclude  that  the  use  of  an  external  nasal 
dilator  has  no  discernible  physical  Impact  on  athletic  performance. 


Department  of  Pediatrics 

Neoraei 

The  purpose  of  this  study  was  to  investigate  the  factors 
involved  in  the  sometimes  significant  difference  in  ear  ve. 
finger  pulse  oximetry  readings  in  CP  patients.   A  total  of  1S4 
sets  of  simultaneous  oximetry  readinge  were  obtained  using 
multiple  probe  sites.  These  included  the  right  (R)  and  left 
(L)  ear  measured  with  the  Ohmeda  3700  oximeter  and  the  R  and  L 
index  finger  measured  with  both  the  Ohmeda  3700  and  Nellcor 
N100  oximeters.  The  largeet  mean  difference  was  between  the  L 
ear  vs  R  finger  (delta  ear-finger)  end  was  only  2.03%; 
however,  the  SD  was  large  (6.52%).  There  wae  no  elgnlf leant 
correlation  between  delta  ear-finger  and  the  magnitude  of 
finger  clubbing  (spearman  rho-0.164,  p-ns).  There  were  no 
significant  differences  between  the  readings  on  the  R  and  L 
ear  or  between  the  R  and  L  finger  when  using  the  eame 
oximeter.  There  was  a  consistent,  small,  but  significant 
difference  in  readings  between  oximeters  as  measured  on  both 
fingers  end  wss  greatest  on  the  right.  The  mesn(SD)  02  SAT  of 
the  R  finger  -  93.31  (5.20)  with  the  Nellcor  vs.  92.49(6.52) 
with  the  Ohmeda  (fKO.OOOl).  Part  of  this  difference  can  be 
attributed  to  the  automatic  correction  by  the  Ohmeda  for 
carboxy  and  mat  hgb.  However, the  biggest  factor  was  02 
saturation.  As  the  patient's  right  finger  saturation  decreased 
the  delta  ear-finger  increased  (peareon  rho  -  -0.876, 
[X0.001).  In  addition,  the  delta  ear-finger  aleo  increased  ss 
the  PVC  and  PEV1  decreased  (pesrson  rho—0.259  and  -0.264, 
p<0.01  and  0.01  respectively).  Conclusion]  The  difference 
between  ear  and  finger  readings  increases  as  patien--  k 
more  hypoxemic.  These  differences  are  great  enough  to 
potentially  impact  the  decision  to  use  supplemental  oxygen. 


Respiratory  Care  •  November  '95  Vol  40  No  11 


1165 


New  Expiratory 
Valve  with 
low  resistance 


Clear  chamber  for  continued 
visualization  of  MDI 
actuation  and  valve  opening 


LATION  RESISTANCE 

.a                                                                                                * 

/ 

S^ 

INHALATION  VALVE 
BACK  PRESSURE 


INHALATION  FLOW(LPM) 


Clinicians,  parents  and  pediatric  patients  can  be  confident  of  improved 
delivery  of  MDI  medications  to  the  lungs.  This  is  accomplished  while 
allowing  ease  of  inhalation  and  exhalation,  reduction  of  dead  space  in  the 
mask  and  maintaining  a  proper  fit  and  seal  around  the  mouth  and  nose. 
Even  patients  with  low  inspiratory/expiratory  pressures  and  flow  rates 
can  effectively  use  the  dual  valve  AeroChambers®  with  Masks1  (see  charts 
below,  left). 

The  AeroChamber®  with  Mask  is  a  cost  effective2  and  portable  system,  with 
accelerated  delivery  capability3  and  a  choice  of  two  sizes  of  mask,  small  and 
medium.  You  can  now  provide  greater  patient  comfort,  use  of  a  broader 
range  of  current  aerosol  medications  and  realize  a  faster  therapeutic 
response.3  Additionally,  the  AeroChamber®  system  will  use  less  medication 
when  compared  to  current  Small  Volume  Nebulizer  (SVN)  Therapy.4 


The  Universal  MDI 
receptacle  permits  use 
of  pharmaceutical 
manufacturers' 
approved  actuators 


%  Drug  delivery  from  holding  chambers  with  attached 
facemaskML  Everard  et  al,  Archives  of  Disease  in  Children, 
Vol.  67,  No.  5,  May  1992 

2.  Substitution  of  Metered  Dose  Inhalers  for  Hand  Held 
Nebulizers.  Success  and  Cost  Savings  in  a  large.  Acute  Care 
Hospital,  Bowton,  DL,  et  al,  Chest  101  (2) :  305-8, 1992  Feb. 

3ii  Metered  Dose  Inhalers  with  Spacers  vs  Nebulizers  for 
Bronchodilator  Therapy  in  a  Pediatric  Emergency  Department, 
Chou,  K],  et  al.  Am.  J  of  Dis  of  Child,  volume  147,  No.  4  April  1993 

4-  Efficacy  of  Albuterol  Administered  by  Nebulizer  versus  Spacer 
Device  in  Children  with  Accute  Asthma,  Karem,  E.,  e*  al  J,  Ped  123 

(21-313-7,1993 


Pe 


The  New  Dual-Valve  Clear 
AeroChamber®  with  Mask 
is  part  of  the  complete 
AeroChamber®  Family  of 
Aerosol  Holding  Chambers 
from  Monaghan  Medical 
Corporation. 


Sponsors  of  A  ARC'S 
Peak  Performance  USA  Program 


4&c 

ENITH  JWL 


MONAGHAN  MEDICAL  CORPORATION 

P.  O.  Box  2805,  Plattsburgh,  NY  12901 

800-833-9653  /  518-561-7330 

Fax:  518-561-5660 
Circle  144  on  reader  service  card 
Visit  AARC  Booth  1128  in  Orlando 


Sunday,  December  3,  12:45-2:40  pm  (Rooms  230C-D) 


CASE  MANAGEMENT  APPROACH  TO  THE  CARE  OF  VENTILATOR 
DEPENDENT  PATIENTS  IN  A  COMMUNITY  HOSPITAL    Keith  G.  Rasmussen  MS. 
RRT.  Mary  E   Lough  RN.  MS.  CCRN.  Sequoia  Hospital,  Redwood  City,  CA. 
Introduction:    \ 'entilator  dependent  patients  are  an  expensive  sub-category  of  intensive  care 
patients   Case  Management,  combined  with  a  multidisciplinary  approach,  effectively 
coordinates  care  and  controls  costs  for  these  patients.  In  1991,  patients  requiring  10  or  more 
days  of  mechanical  ventilation  (Pts  a  10)  were  retrospectively  evaluated.  Diagnoses  were 
surgical  (3)  and  cardiac  (12),  The  average  duration  of  ventilation  per  patient  (LOV)  was  29 
days   Average  length  of  hospital  stay  (LOS)  was  47  days.  Outcomes  were;  estubated  (7), 
expired  (7)  or  transferred  ventilator  dependent  (1).  In  1992  a  Task  Force  was  formed  to 
study  and  support  changes  in  patient  care  management    A  muttidisuplinary  approach, 
coordinated  by  Case  Managers  (Clinical  Nurse  Specialist  and  Respiratory  Care  Educator) 
was  implemented  in  mid  1993.  Method;    All  Pts  S  10  are  included,  without  other  entry  or 
exclusion  criteria.  Diagnoses  in  1993/1994;  surgical  (1/1),  cardiac  (12/6)  and  medical  (4/5). 
On  ventilator  day  four,  the  Case  Manager  contacts  the  physician  and  family  and  sets  up  a 
mulli disciplinary  conference   Conference  panicipants  are    Case  Manager.  Patient  and 
Family.  Physician.  Nurse.  Respiratory  Therapist.  Dietitian,  Pharmacist,  Rehabilitation 
Specialists  (PT,  OT,  Speech),  Social  Worker,  and  Discharge  Planner.    Objectives  of  the 
conference:  educate  family  and  health  professionals  about  current  medical  conditions; 
establish  joint  goals  and  plan  of  care;  discuss  discharge  options;  answer  family  questions. 
Conferences  create  an  environment  where  decisions  by  consensus  occur  and  goals  arc  set  to 
move  care  progressively  forward.  Conferences  are  repealed  weekly  until  the  patient  is 
extuhated.  discharged,  transferred  or  deceased    The  Case  Manager  assures  compliance  with 
the  established  plan  of  care,  and  maintains  communication  with  the  physician,  patient  and 
family  members    Results:    When  compared  to  1991  using  the  Kruskal-Wallis  Multiple 
Comparison  test  (non-parametric).  LOS  and  LOV  for  1993  and  1994  were  significantly 
reduced  (p  <  .05)  for  Pis  2  10.  While  LOS  for  all  hospital  patients  declined  in  93/94  (-1  %/ 
-7%),  the  declines  for  the  Pts  2:  10  group  were  substantially  greater  (see  table).  Outcomes 
for  93/94  were,  extubated  (8/6).  expired  (7/4)  and  transferred  ventilator  dependent  (2/2). 


LOS  1  LOV 

1991  (n-15) 

1993 

n  =  17) 

1994  1 

11=12) 

Days 
(Range) 

<££) 

%  Change 
from  '91 

,5, 

%Change 
from  '91 

LOS  Pts  2  10 

47  (16-97) 

30(12-88) 

-36% 

22  (14-33) 

-53% 

LOV  Pis  2  10 

29  (10-90) 

20(10-86) 

-31* 

16  (10-26) 

-45% 

Average  charges  pet  patient,  per  day,  for  ventilator  dependent  patients:  in  1993  ■=  $6626; 
in  1994  =  $6937.  Estimated  savings  due  to  decreased  LOS  in  1993:  $1.9  million;  in  1994: 
$2. 1  million.  Experience:  Decreases  in  LOS  are  due  to  coordination  of  care  and  decisions 
made  at  conferences  for  weaning,  transfer  or  withdrawal  of  life  support  Effective  case 
management  of  even  a  small  group  of  expensive  patients  results  in  substantial  cost  savings. 
Conclusions:  Multidisciplinary  Case  Management  approach  to  veniilator  dependent  patient 
care  shortens  length  of  stay,  on  the  ventilator  and  in  the  hospital,  and  reduces  hospital  costs. 


USE  OF  A  REGISTRY  &  RESPIRATORY  THERAPIST-DRIVEN  PROTOCOL 
FOR  NON-INVASIVE  ASSISTED  VENTILATION  <NAV>  IN  THE  HOSPITAL 
SETTrNG  Allen  G.  Kendall  RRT.  Arlcne  Wcnzel  RN.  Peter  C  Gay  MD  Mayo 
Foundation.  Rochester.  Mn  55905 

The  use  of  NAV  has  rapidly  increased  in  the  hospital  setting  but  there  are  no  definitive 
indications  for  its  use  nor  uniformity  of  application  of  this  equipment  In  order  to 
improve  delivery  and  follow-up  care  of  patients  (pts)  receiving  NAV  in  the  hospital 
setting,  we  developed  a  the  rapist -driven  protocol  and  monitored  patient  use  with  a 
nasal  ventilation  registry  The  registry  was  used  to  track  indications,  equipment 
utilized,  documentation  of  need,  and  outcome  in  all  pts  who  were  introduced  to  NAV 
in  the  hospital  setting  from  I98H  to  lu94  The  registry  included  5  pediatric  pts  and 
119  adult  pts  with  the  following  diagnoses  COPD-  38  pts.  ALS-  IK  pts.  other 
neuromuscular  disease-  21  pts.  primary  hypoventilation-  14  pts.  kyphoscoliosis-  14 
pts.  obesity  hypoventilation-  14  pts.  other-  5  pts  Patients  were  introduced  to  this 
therapy  in  the  following  locations  ICU-  88  pts:  general  ward-  22  pts.  sleep  lab-  7  pts; 
chronic  vent  unit-  5  pts.  and  2  pts  were  introduced  in  other  skilled  areas  There  were 
83  pts  who  utilised  a  bilevel  pressure  device  and  4 1  pts  used  a  portable  volume 
ventilator  with  1 15  pts  beginning  via  nasal  mask  and  9  initiating  with  a  full  face  mask 
Thirty  seven  patients  had  used  some  type  of  assisted  ventilation  prior  to  entering  the 
registry  and  approximately  25%  of  the  patients  preferred  a  do  not  resuscitate  status  on 
admission  to  the  hospital  The  mean  total  hospital  days  for  these  pts  was  10.9  ±  9  I 
(Std  Dev)  with  a  mean  total  hours  of  assisted  ventilation  of  120  3  +  94  6  hours 
There  were  80  pts  who  continued  with  this  treatment  after  the  introduction  phase  that 
were  either  stabilized  (46  pts)  or  improved  (34  pts)  Forty-four  pts  discontinued  NAV 
after  the  introductory  phase  either  by  refusal-  13  pts.  rapid  stabilization  or 
improvement-  1 1  pts.  opting  for  CPAP-  8  pts.  expiring-  8  pts.  or  requiring  intubation 
or  tracheostomy-  4  pts  In  the  80  pts  who  continued  NAV  after  hospital  discharge, 
the  documentation  for  continued  use  was  provided  by  overnight  oximetry-  29  pts. 
polysomnograhy-  27  pts.  or  arterial  blood  gases  and  clinical  judgment-  24  pis  The 
outcome  of  these  80  continuing  pts  when  seen  at  various  times  for  first  follow  up  is 
as  noted  stable  or  improved-  44  pts.  worse-  7  pts.  later  discontinued-  1 1  pts.  and  lost 
to  follow  up-  18  pts  We  concluded  that  35  5%  of  pts  that  are  introduced  to  NAV  in 
the  hospital  setting  were  not  able  to  tolerate  this  Of  the  patients  available  for  follow- 
up  who  were  discharged  to  home  with  assisted  ventilation,  the  majority  (51  of  62  pts 
or  82.3%)  continued  this  treatment  More  formal  documentation  of  the  need  for  this 
ongoing  treatment  was  not  provided  by  overnight  oximetry  or  polysomnography  in 
many  (24  of  80  pts  or  30%)  We  continue  to  use  this  registry  to  better  establish 
indications,  refine  the  introduction,  urge  documentation  of  continued  use,  and  improve 
follow-up  for  patients  using  NAV 

OF-95-222 


COMPARING  THE  LENGTH  OF  VENTILATION  ON  CABG  PATIENTS 
PRE/POST  WEANING  PATHWAY. 

Daniel  J_=.  Reily  BS.  RRT.  Michael  Santoro  BS.  RRT. 
John  Sestito  BA.  RRT,  David  Shulkin  MD. 
University  of  Pennsylvania  Medical  Center,  3400 
Spruce  Street,  Philadelphia,  PA.  19104-4283. 
Introduction:  This  study  was  undertaken  to  compare 
the  length  of  ventilation(LOV)  on  patients  after 
undergoing  a  coronary  artery  bypass  graft (CABG)  with 
and  without  a  weaning  pathway .  Background:  Previous 
to  this  study  post  CABG  patients  were  weaned  by  a 
task-oriented  method.  The  physician  writes  an  order 
and  respiratory  care  practitioners(RCP)  carries  it 
out.  The  pathway  was  designed  to  have  the  RCP  more 
actively  involved  in  the  weaning  process  {RT-driven 
weaning).  The  pathway  called  for  the  patients  to  be 
weaned  from  the  ventilator  by  RCP  without  a  physician 
order.  RCP  followed  specific  guidlines  to  insure 
efficiency  and  patient  safety.  Criteria:  Patients 
enrolled  in  the  pathway  received  a  non  complicated 
CABG  without  any  other  surgical  procedure.  Exclusion 
criteria  included  excessive  bleeding,  blood  pressure 
complications,  complex  acid-base  disturbances,  acute 
neurological  event,  packed  open  chest,  intraortic 
balloon  pump,  excessive  narcotics  and  a  history  of 
lung  disease.  Method:  Data  were  collected  on  all  CABG 
patients  for  a  two  month  period  as  a  control  group. 
The  data  were  analyzed  and  it  was  found  that  41 
patients  met  the  criteria  to  be  placed  in  the  pathway 
had  the  pathway  been  in  effect  at  this  time.  Then  the 
pathway  was  initiated  with  the  same  exclusion 
criteria.  Data  were  collected  on  all  CABG  patients 
until  41  patients  were  enrolled  in  the  pathway.  The 
data  collected  on  the  41  patients  who  met  the 
criteria  pre  pathway  (control  group)  was  compared  to 
the  41  patients  who  participated  in  the  pathway. 
RESULTS:  The  mean  LOV  pre  pathway  was  11.2  ±  4.2 
hours  on  the  control  group.  Using  RT-driven  weaning 
the  mean  LOV  decreased  to  6.4  ±   1.4  hours.  This  was  a 
significant  difference  [p<0.001].  CONCLUSION:  We 
determined  this  pathway  to  be  a  success  by  the 
statistically  significant  reduction  in  LOV  and  the 
opportunity  for  the  RCP  to  be  more  actively  involved 
in  Datient  outcome  instead  of  performing  a  task. 

OF-95-021 


OPTIMIZING  VENTILATOR  CARE  USING  A  VENTILATOR  MANAGEMENT 
TEAM  IN  A  PEDIATRIC  INTENSIVE  CARE  SETTING  Randy  Scott  BS  RCP  RRT. 
Ronald  Perkin  MD,  Mark  Rogers  BS  RCP  RRT.Tom  Malinowski  BS  RCP  RRT.  Leo 
Langga  BS  RCP  RRT,  Loma  Linda  University  Children's  Hospital.  Loma  Linda. 
California 

INTRODUCTION  Ventilator  care  constitutes  a  significant  cost  in  intensive  care 
management  We  hypothesized  dial  a  ventilator  management  team  (VMTt  would  optimize 
ventilator  care,  reduce  ventilator  hours,  and  increase  the  respirator.'  care  practitioner's 
(RCP)  involvement  in  patient  management  METHODS  This  was  a  retrospective  study 
performed  in  a  25  bed,  level  3  pediatric  intensive  care  unit  (PICU)  The  VMT  consisted  of 
PICU  intensivist,  bedside  RCP.  RC  supervisors,  and  RC  director  The  residents,  fellows, 
and  bedside  nurses  were  invited  to  participate  with  the  VMT  Rounds  occurred  once  a  week 
and  consisted  of  the  RCP  presenting  a  brief  history  and  physical,  current  medications, 
pertinent  lab  data,  and  respiratory  care  After  a  discussion  of  the  current  regimen,  a 
consensus  was  reached  pertaining  to  the  ventilator  care  plan  supplied  by  the  members  of 
the  VMT  and  recommendations  for  changes  were  made  if  indicated  Within  24  to  48  hours 
after  rounds,  recommendations  made  by  the  VMT  were  evaluated  to  determine  patient 
benefits  Positive  outcomes  were  defined  by  any  of  the  following  documented  reduction  in 
measured/observed  work  of  breathing,  improved  synchrony  with  the  ventilator,  blood  gases 
improved  to  desired  range,  reduction  in  ventilator  settings,  or  cxtubation  A  negative 
outcome  was  evidenced  by  clinical  deterioration  (blood  gases,  hemodynamics)  or  reversal 
of  implemented  changes  The  VMT  visited  every  patient  requiring  CMV 

Group  I  (Pre  VMT)  Group  2  (Post  VMT) 

Study  Period  July  93-Dcc  93  July  94-Dec  94 

Population  227  205 

The  two  groups  were  compared  for.  duration  of  CMV,  ICU  stay,  and  hospital  length  of  stay 
(LOS)  Additional  group  2  data  included  the  number  of  recommendations  made  by  the 
VMT,  number  of  recommendations  actually  implemented,  and  patient  tolerance  to  the 
changes  RESULTS  Of  the  205  patients  in  group  2  admitted  during  the  time  period 
studied,  the  VMT  rounded  on  1 2 1  individual  patients  Ventilator  recommendations  were 
made  in  60  patients,  with  55  being  implemented  The  five  recommendations  not 
implemented  were  due  to  attending  physician  disagreement  The  VMT  agreed  with  the 
management  stralcgy  of  the  remaining  61  patients  Of  the  55  changes  recommended  by  the 
team.  5 1  changes  had  a  positive  outcome,  3  had  mixed  results  and  1  had  a  negative 
outcome  Between  group  analysis  utilized  ANOVA  (p  <  0,05) 

Group  1  (Pre  VMT)     Group  2  (Poit  VMT)     Significance 


ICU  LOS 
Hosp.  LOS/dayi 
Dur.  of  CMV/hr. 

Of  the  two  groups 


171  +  58 


10  +  2 
17  +  3 

95  +  22 


p  <  0  05 
p<0.05 


mparcd,  group  2  showed  ;i  M.mstK.ilh  significant  decrease  i: 
ventilator  hours  and  a  decrease  in  overall  LOS  (  p  <  0  05)  CONCLUSIONS  VMTs  can 
optimize  respiratory  and  ventilator  care  modalities  with  positive  results  Ventilator  hours 
and  LOS  can  be  reduced  w  Ith  the  use  of  VMTs. 


168 


Respiratory  Carh  •  November  '95  Vol  40  No  1 


Sunday,  December  3,  12:45-2:40  pm  (Rooms  230C-D) 


FAVORABLE  PATH.  N  I  Ol    ICOMI  S  AND  SIGNIFICANT  SA\TNGS  FOR  PATIENTS  PLACED  C 
•JE  YEAR  STUDY 


]  992  prcprotocol  DRG  studv  - 

c  ABG/paiiCTii 


heart  surgery    The  DRG  si 
Karen  Nygard,  R-  R  T  ,  Si 


POST-OPCRATtVl  RESPIRATORY  CAR!  PROTOCOL  POR  LUNG  TRANSPLANT 
PATIINTS  -  REPORT  OP  A  METHOD    Lucv  Keaer  MBA.RRT,  Barbara  Higgjns  RN, 
MSN.  Mananne  Potts  RRT,  Cleveland  Clinic  Foundation.  Cleveland.  Ohio 

Successful  lung  transplantation  began  in  the  early  1980s  The  St.  Louis  International  Lung 
Transplant  Registry  reports  that  as  of  December  31,  1994.  44  centers  in  the  United  States  and 
33  centers  outside  the  US.  have  performed  3,836  transplants  which  includes  2,346  single 
lung  transplants,  1 .252  bilateral  sequentials,  and  230  en-bloc  doubles  Of  these,  2,227  were 
performed  in  the  US  Two  year  survival  rates  have  improved  from  51%  in  the  period  from 
1983-1989.  to  68%  for  1991-1994    During  this  time,  very  little  has  been  written  on  the  post- 
operative respiratory  care  delivered  to  this  patient  population  in  spite  of  the  high  risk  that 
exists  for  respiratory  complications  due  to  impaired  cough  reflex  from  lung  denervation, 
impaired  mucociliary  action,  and  immunosupression 

Lung  transplantation  began  at  the  Cleveland  Clinic  Foundation  in  1990.  In  May  of  1991,  we 
instituted  a  protocol  for  the  post -operative  care  of  lung  transplant  patients  which  includes: 
aerosolized  bronchodilator  therapy  q  4  hours  while  awake,  bronchopulmonary  hygiene  (with 
specific  techniques  for  single  vs  double  lungs)  q  4  hours  while  awake,  twice  daily  peak  flow 
measurements,  oxygen  titration  and  ambulation.  For  postural  drainage  and  percussion/ 
vibration  procedures,  single  transplants  are  positioned  tn  the  lateral  decubitis  position  with 
the  transplanted  lung  up  Positioning  the  native  lung  up  is  avoided  in  an  attempt  to  prevent 
draining  secretions  and  possibly  infection  into  the  new  lung.  During  the  bph  procedures 
(postural  drainage,  percussion/vibration),  suctioning,  and  ambulation,  the  patient's  oxygen 
saturation  should  be  monitored  and  oxygen  concentration  adjusted  to  maintain  an  Sp02  of  2 
93%,  as  these  procedures  may  cause  the  patient's  saturation  to  drop  precipitously  When 
performing  deep  breathing  exercises,  single  lung  transplant  patients  are  instructed  to  splint, 
or  compress,  the  native  lung  side  in  an  attempt  to  direct  air  preferentially  to  the  new  lung  for 
improved  expansion.  Peak  flow  measurements  will  be  performed  morning  and  evening 
throughout  the  entire  hospital  stay  and  then  daily  at  home  to  monitor  for  possible  rejection- 
Emphasis  is  put  on  adequate  rest  for  the  patients  at  night.  The  protocol  is  carried  out  for  2 
weeks  following  transplantation,  after  which  the  patient  is  treated  according  to  our  standard 
Respiratory  Therapy  Consult  Service  protocol.  Should  the  patient  remain  in  the  ICU  for 
longer  that  2  weeks,  the  protocol  is  followed  for  72  hours  before  converting  to  the  standard 
RTCS  protocol 

Since  the  initiation  of  our  protocol,  there  have  been  90  lung  transplants  performed  at  CCF 
(57  singles,  29  doubles.  4  en-bloc)  with  an  overall  survival  rate  of  61%  The  major 
complications  have  been  rejection  (90%  having  at  least  1  episode  of  rejection)  and  infection 
(30%  on  bronchoscopy)  Anecdotally  .as  provided  by  the  case  manager  for  the  lung  transplant 
nursing  unit  and  the  primary  respiratory  therapist  working  in  this  unit  (Mananne  Potts),  there 
were  no  instances  of  a  lung  transplant  patient  treated  by  our  protocol  returning  to  the  ICU 
because  of  inappropriate  or  insufficient  respiratory  care  In  view  of  the  increase  in  numbers  of 
patients  undergoing  lung  transplantation  (272  from  1983  -  1989  to  2529  from  1992  -  1994)  a 
more  detailed  study  of  the  appropriate  respiratory  care  for  this  patient  population  seems 
warranted 

OF-95-172 


TRACH  TEAM:  A  MULTIDISCIPLINARY  APPROACH  TO  MANAGING 
TRACHEOSTOMIES  IN  A  UNIVERSITY  TEACHING  HOSPITAL  AND 
TRAUMA  CENTER.    CL  Kasper  RRT.  CR  Stubbs  RRT.  JA  Barton.  DJ 
Pierson  MD,  Harborview  Medical  Center,  Seattle  WA 

Introduction/Background.   During  a  1-yr  observational  period,  we  previously 
demonstrated  (RespirCare  1994;39:1 110)  that  pts  who  underwent 
tracheotomy  at  our  institution,  or  were  admitted  with  a  trach,  comprised  a 
heterogeneous  group  in  terms  of  admitting  diagnosis,  managing  service,  need 
for  respiratory  care,  and  outcome.  This  study  tested  the  hypothesis  that  an 
organized,  murti disciplinary  approach  to  assessment  and  management  in  pts 
with  trachs  would  have  a  measurable  impact  on  the  care  of  these  pts  in  our 
hospital.  Materials  and  Methods.    At  the  conclusion  of  the  observational 
period  (Y1,  7/92-6/93)  we  formed  a  trach  team,  comprised  of  RCPs  and 
speech  pathologists,  with  the  medical  director  of  RC  and  an  OTO/H&N 
surgeon  available  for  consultation,  and  also  developed  protocols  for  trach 
management  and  decannulation,  which  were  reviewed  and  approved  by  the 
chiefs  of  all  medical  services  as  well  as  nursing  management.  The  trach 
team  rounded  on  every  trached  pt  once  each  week.  We  reviewed  the  charts 
of  all  pts  with  trachs  for  1  yr  following  formation  of  the  team  (Y2,  7/93-6/94), 
and  compared  the  results  with  those  from  Y1    Results.  The  numbers  of  trach 
pts  (112)  and  admissions  (152)  available  for  review  were  similar  to  the 
previous  year's,  as  were  pt  demographics  (mean  age  39  yr,  66%  males). 
Somewhat  more  pts  were  admitted  because  of  trauma,  and  to  the  general 
surgery  and  neurosurgery  services,  than  in  Y1,  and  more  pts  were  ventilated 
on  admission.  However,  hospital  mortality  (7%),  length  of  stay  (mean  39 
days,  range  10-86),  and  the  incidences  of  ARDS  (9%)  and  hospital-acquired 
pneumonia  (36%)  were  the  same  in  Y2  and  Y1.  More  pts  had  progress  notes 
by  RCPs  in  Y2  (96%  vs  69%,  p  =  0.000).  The  trach  team  made 
recommendations  in  2/3  of  pts  with  trachs  during  Y2,  and  these  were  followed 
by  the  primary  team  87%  of  the  time.  More  pts  had  trach  tubes  changed 
during  Y2  (69%  vs  52%,  p  =  0.005);  although  the  initial  tubes  used  were  the 
same  in  Y2  &  Y1,  in  Y2  more  pts  were  switched  to  double-cannula  tubes  (p  ■ 
0.000),  especially  those  with  pre-existing  trachs  on  admission.  The  number  of 
pts  decannulated  was  the  same  both  years  (30%  Y2  vs  22%  Y1,  p  =  0.126). 
Conclusions.   In  our  university  teaching  hospital  and  trauma  center,  institution 
of  a  multi disciplinary  trach  team  resulted  in  improved  patient  care. 


MULTIDISCIPLINE  APPROACH  TO  A  SUCCESSFUL  COST  REDUCTION  INITIATIVE: 
CHANCING  FROM  DISPOSABLE  TO  PERMANENT  OXIMETRY  SENSORS. 
Daniel  Pavllk  M.Ed..  RRT.  Greg  Nichols  MSA,  RRT,  Jim  Martin  BS,  RRT,  Pulmonary 
Services  Department,  MetroHealth  Medical  Center,  Cleveland,  Ohio 

Introduction:  Conversion  from  disposable  sensors  (DS)  to  permanent  sensors  (PS)  In  a 
major  academic  medical  center  requires  significant  planning,  mulddeparrment  Input,  staff 
training,  and  ongoing  user  support.  Continuous  oximetry  monitoring  Is  a  standard  of  care 
for  patients  receiving  oxygen  and/or  ventilation  support  In  our  critical  care  units  ( I  1 4 
beds).  Other  high  use  units  are  ED,  PACU,  and  LfltD.  We  convened  to  all  DS  In  '88  to 
provide  caregivers  with  readily  available,  easy  to  apply  sensors.  We  assumed  a  cost  savings 
by  eliminating  lost  or  damaged  PS  and  Improving  caregiver  efficiency.  In  the  last  half  of  '90 
our  critical  care  oximetry  monitoring  peaked,  triggered  by  revised  critical  care  guidelines 
and  availability  of  monitoring  units.  In  '92  an  attempt  to  convert  back  to  PS  In  NICU 
failed.  Pulse  oximetry  monitoring  hours  Increased  32%  between  '92  and  '93.  Cost  for  '93 
DS  reached  $76,959  providing  us  an  Incentive  to  develop  a  second  conversion  strategy. 
Methods:  Key  leaders,  representing  high  use  areas,  were  Identified  from  nursing, 
purchasing,  and  respiratory  care  along  with  representatives  from  purchasing  and  clinical 
engineering.  We  reviewed  the  potential  for  cost  savings  and  developed  a  plan  Incorporating 
previous  strategies  in  addition  to  establishing  central  control  for  PS  replacement,  removal  of 
DS  from  the  storeroom,  and  technical  support  Identifying  non-functional  sensors.  Nurse 
managers  (ustlfled,  to  the  conversion  team  members,  the  number  of  PS  required  for  their 
units.  The  inventory  needed  for  the  replacement  of  damaged,  lost,  and  non-functional  PS 
was  determined  by  Clinical  engineering  staff.  They  also  maintained  control  over  the 
distribution,  purchase,  and  tracking  of  all  sensors  against  warranty  dates,  shipping 
nonfunctional  sensors  to  the  manufacturer  for  replacement.  Results: 


YEAR 

MONITORING 
HOURS/YEAR 

SENSOR 
EXPENSE/YEAR 

SENSOR 

EXPENSE/HOUR 

1992 

685,464 

56,186 

0.08 

1993 

707,464 

76,959 

0.1  1 

1994 

425,216 

26,005 

0.06 

Guidelines  were  Initiate 

d  In  '94  to  address  th 

tendency  ol  over-mo 

Itortng  In  non-critical 

care  units.  Conclusion:  Changeover  from  DS  to  PS  Is  challenging  and  can  fall  If  taken 
lightly.  In  addition  to  acquiring  staff  buy-In  and  providing  education,  It  Is  crucial  to  Include 
all  departments  that  engage  In  sensor  ordering,  storage,  and  distribution  In  the  planning 
process.  The  partial  change  may  have  contributed  to  the  staffs'  perception  the  changeover 
was  not  fully  supported  and  provided  an  opportunity  to  return  to  the  old  ways.  A  well 
defined  monitoring  program  supports  tracking  compliance  and  data  collection.  The  tracking 
process  provides  warranty  Identification  eliminating  unwanted  sensor  disposal. 


Respiratory  Care  •  November  "95  Vol  40  No  1 1 


169 


Sunday.  December  3,  12:45-2:40  pm  (Rooms  230C-D) 


STAFF  EMPOWERMENT  IN  A  BARGAINING  UNIT  ENVIRONMENT  CONTRIBUTES 
TO  REDUCTION  IN  MIDDLE  MANAGEMENT. 

Daniel  Pavllk,  M.Ed.,  RRT.  Gregory  Nichols,  MSA,  RRT,  Pulmonary  Services  Department, 
MetroHealth  Medial  Center,  Cleveland,  Ohio 

Introduction:  The  challenge  to  reduce  cost  without  infringing  on  quality  patient  care 
ironically  centers  on  our  most  expensive  resource  •  direct  patient  care  staff.  In  our  700  + 
bed  academic  medical  center  the  RRTs  and  CRTTs  are  in  a  union.  Our  goal  was  to  design  a 
program  to  provide  shift  leadership  using  union  employees  and  reduce  supervisor  staff. 
Bargaining  unit  contract  language  and  tradlUonal  union  values  provided  a  challenge  to  staff 
empowerment.  Methods:  Our  management  team  agreed  to  support  a  program  which 
empowered  staff  in  a  leadership  role  for  coordination  of  a  shifts  clinical  activities.  Two 
clinical  supervisor  positions  were  retained.  The  management  team  Identified  qualities 
needed  to  be  successful  as  a  "Team  Leader"  (TL),  developed  an  evaluation  tool.  Two 
clinical  specialists  and  the  manager  chose  eleven  staff  they  suspected  would  meet  these 
qualifications.  Staff  were  rated  by  each  team  member  and  an  average  score  was 
determined.  Scores  were  grouped,  and  a  cut  score  determined.  The  director  met  with  the 
union  steward  sharing  written  guidelines  identifying  the  shift  res  ponsl  bill  ties.  The  guidelines 
included  on-call  management  support  for  all  hours  a  TL  was  assigned  to  coordinate  a  shift. 
An  introductory  meeting  was  held  with  each  potential  TL,  sharing  program  goals, 
evaluation  criteria,  assignment  guidelines,  and  asked  to  provide  frank  and  candid  concerns  if 
placed  in  the  assignment.  The  nine  staff  agreed  to  pilot  the  program  and  were  scheduled 
for  orientation.  Following  orientations,  TLs  were  scheduled  on  weekends,  holidays,  and 
during  supervisor  vacations.  Results:  Team  Leaders  were  excited  yet  apprehensive  about 
encountering  peer  pressures,  dealing  with  friends,  and  confronting  difficult  staff.  Some  TLs 
were  not  voting  union  members.  Fundamental  union  culture  was  being  challenged  by 
assigning  staff  the  responsibility  of  giving  work  direction  and  making  assignments  for  union 
"brothers"  and  "sisters".  Difficulties  arising  from  union  resistance  was  minimal.  The 
program  was  implemented  in  12/94.  At  the  same  time,  3.5  FTE  supervisor  positions  were 
deleted  and  provided  an  expense  reduction  of  $1  79,200.  In  2/95,  staff  and  TLs  were 
surveyed  to  gain  input  on  program  acceptance  and  to  determine  long  term  success.  Staff 
experiences  with  TL  program  were  positive  and  provided  support  for  deleting  the  final  0.5 
FTE  supervisor  position  ($25,600).  Staff  identified  TL  empathy,  better  understanding  of 
the  daily  challenges,  and  more  overall  support  during  the  shift  as  program  strengths. 
Mandating  overtime,  enforcing  the  discipline  policy/ procedure,  authorizing  all  changes  in 
the  number  of  staff/shift,  investigating  critical  occurances,  and  ordering  rental  equipment 
remained  a  management  responsibility.  Condusions:  Team  management  decisions  expand 
potentials  and  provide  direction  to  tough  decisions  on  staff  reduction.  Not  all  staff 
reductions  end  in  reduced  patient  quality  and  staff  morale.  Many  individuals  possess 
leadership  qualities  which  are  dormant  or  exercised  In  non-trad Itiona I  ways.  Identifying 
these  Individuals  and  empowering  them  in  critical  roles  can  provide  |ob  satisfaction  and 
improved  employee  morale  while  reducing  expenses.  Staff  empowerment,  provided  with 
adequate  management  support  can  work  in  a  bargaining  union 


OF-95-038 


PEDIATRIC  DEPARTMENT  DEVELOPED  METHOD  TO  ACHIEVE  INTERNAL  REDESIGN 

Chnsune  A  Bagfil  TTT  Childrens  Hospital  of  Wisconsin,  Milw  WL  In  March  1994  the 
RCS  dept  at  Childrens  Hospital  of  Wisconsin  anticipated  hospital  admirustraJjon  would  be 
developing  plans  for  restructuring  Our  depfs  management  section  feft  it  was  our  responsibility 
to  take  a  proactive  role  in  the  redesujn  of  our  depfs  structure  Method:  In  April  we  met  with  the 
staff  and  developed  a  task  force  of  volunteers  The  hospital's  organizational  specialist  served  as 
our  group  facilitator  We  outlined  our  objectives  We  developed  an  analysis  of  the  depfs 
perceived  strengths,  opportunities,  weaknesses  and  threats  We  became  familiar  with  literature  on 
restructuring  and  redesign  400  internal  customer  surveys  were  distributed  and  9  external  surveys 
were  sent  to  childrens  hospitals  of  relatively  comparable  capacity  K«utU:  1 18  internal  surveys 
and  9  external  surveys  were  returned  Several  alternative  models  were  created  based  on  survey 
results,  dept/  hospital  objectives  and  provision  of  value  added  service  We  developed  a  final 
organizational  model  that  was  accepted  by  our  medical  director  and  hospital  administrator  The 
model  was  presented  to  the  RCS  staff  and  everyone  was  required  to  reapply  for  positions  All 
staff  were  rehired  along  with  approval  to  add  three  additional  FTE's 


Internal  customer  requirements 
expected  from  respiratory  care 

equipment  setup  and  maintenance 

providing  timely  txs 

availability 

pt  and  family  educaUoD 

:  intervention 

consultant 

pt  assessment 

communi  can  on 

professional]  snVattitude 

ventilator/airway  management 

teamwork 

flexibility/other  pt  cares 

instructing  nursmg 

externa]  survey  results 

number  of  depfs  recently  restructured 

who  initiated  dept  restructuring? 


•/. 


does  depL  meet? 


iyes 


22%  no 

1 8%  consultant 


how  are  staff  assigned? 


i  administration 
1 8%  dept  director 

30%  fixed  30%  rotate 

20%  rvuVacurty  10%  workload 

10%  tx/intervention  form 
78%  yes  22%  no 

50%  decreased  30%  increased 

20%  no  change 
arc  PRN/pool  staff  utilized?  50%  yes  50%  no 

Conclusions:  Dept  redesign  can  be  accomplished  internally  Respiratory  care  practitioners  should 
take  a  proactive  role  to  insure  they  are  members  of  a  progressive,  effective  and  quality  dept 

OF-95-055 


PEDIATRIC  RESPIRATORY  DRIVEN  PROTOCOLS:    APPROPRIATENESS  OF 
THERAPY,  ECONOMIC  SAVINGS  AND  PATIENT  OUTCOMES-T  Mitchell  RRT. 
M  Miller  RRT,  D  Habib  MD  and  G  Silvestri  MD.  Medical  University  ol  South 
Carolina  Children's  Hospital,  Charleston,  South  Carolina 

Objective:  To  develop  and  implement  a  therapeutic  and  cost  effective  respiratory 
therapy  protocol  program  for  pediatric  general  floor  and  ICU  patients   Materials 
and  Methods:  Following  a  literature  search  and  evaluation  of  Clinical  Practice 
Guidelines,  assessment  criteria  were  established  to  determine  the 
appropriateness  of  Pediatric  Respiratory  Care  orders.  Assessments  were  based 
on  a  rated  scoring  system  for  patient  history,  physical  examination  and 
documented  indications    Four  Registered  Respiratory  Therapists  (RRT) 
participated  in  the  data  collection  at  our  148  bed  facility    Interraler  reliability  and 
physician  assessment  Inservicing  was  performed  to  document  consistency  and 
accuracy  of  the  assessments     Pre-protocol  data  for  172  pediatric  patients 
determined,  16  (18%)  Hand  held  nebulizer  (HHN)  and  15  (22%)  Chest 
physiotherapy  (CPT)  treatments  were  not  indicated   The  patient  assessment 
program  was  presented  to  the  pediatric  physicians  for  hospital-wide 
implementation    Three  hundred  and  ninety  six  patients  were  assessed  over  a 
two  month  period   Adverse  patient  outcomes  were  monitored  through,  1 
occurrence  reports  {documentation  of  adverse  patient  reactions),  2.  increases  in 
modality  or  frequency  of  Rx  within  24  hours  of  a  completed  patient  assessment 
and  3  variance  reports  (protocol  documentation  of  disagreement  in  physician 
therapy  ordered  vs   therapist  assessment).    Economic  savings  were  calculated 
based  on  patient  charges,  not  cost.    Labor  estimates  were  derived  from  applying 
AARC  timed  work  units  to  the  number  ol  nonlndicated  therapies     Interrater 
reliability  was  compared  using  Pearson  correlation  coefficient.  Results:  Four 
hundred  sixty  six  HHN  and  870  CPT  orders  were  evaluated.  Protocol 
assessment  resulted  in  a  reduction  of  140  (31%)  HHN's  (p<0  05)  and  182  (22%) 
CPTs  (p<005)    The  majority  of  nonindicated  therapies  were  a  result  of 
Irequency  discrepancies  (69%).  not  inappropriate  modality  (31%)  Ten  {  03%) 
orders  (or  therapy  resulted  in  an  Increased  frequency   The  approximate  annual 
savings  In  patient  charges  would  be  $244,000  00    Of  that  total,  $105,000  00  is 
attributable  to  labor  costs  (representing  3  4  full-time  staffing  equivalencies.)  No 
adverse  outcomes  were  noted   Three  variance  reports  were  submitted  with  the 
therapies   administered  as  ordered    Assessments  were  highly  reproducible 
between  therapists  (Pearson  r=  0  9)   Conclusion:  1    Pediatric  Respiratory  Driven 
Protocols  substantially  decreased  the  frequency  of  procedures  administered  at 
our  Institution     2   No  adverse  effects  were  noted  when  therapies  were  altered  to 
meet  protocol  guidelines.  3  A  major  cost  savings  can  be  realized    4   Pediatric 
Respiratory  Driven    Protocols  for  HHN/CPT  can  be  effectively  administered  when 
a  rigorous  protocol  Is  developed,  trained  assessors  are  utilized,  physician  input 
and  education  occurs  and  current  practice  guidelines  are  followed 


This  publication 
is  available  in 
microform. 


Jniversity  Microfilms 

International  reproduces  this 
publication  in  microform: 
microfiche  and  16mm  or 
35mm  film.  For  information 
about  this  publication  or  any 
of  the  more  than  13,000  titles 
we  offer,  complete  and  mail  the  coupon  to:  University 
Microfilms  International.  300  N.  Zeeb  Road.  Ann  Arbor. 
MI  48106.  Call  us  toll-free  for  an  immediate  response: 
800-521-3044.  Or  call  collect  in  Michigan,  Alaska  and 
Hawaii:  313-761-4700. 

Please  send  information  about  these  titles 


Name 

ulion 

Arfrfrixis 

Cilv 

Stain                                                                                  Zip 

Phnm.1               1 

University 

Microfilms 
International 


1170 


Rkspiratory  CARE  •  Novhmbhr  '95  Vol  40  No  1 1 


1  xhalation  Valve 


Airway  Pressure  Limit 


OXYGEN 


LIFECARE 


PLV-102 


## 


Percent  O., 


r  l:«)  'I 

IM\ 


Internal  Fxternal 


NEED  OXYGEN? 

With  this  portable  ventilator  you  can  just  dial  it  in. 


No  adapters.  No  outside  connections.  No  wasted  flow 
of  oxygen.  Just  plug  it  into  your  high  pressure  system 
and  turn  it  on. 

With  the  LIFECARE  PLV®-l  02,  oxygen  regulation  is 
part  of  the  equipment.  You  literally  diol  in  the 
amount  needed-up  to  90%.  And,  oxygen  is  supplied 
only  on  inspiration,  so  there's  a  lot  less  waste. 
Oxygen  delivery  is  simple  and  precise. 


More  features...  and  more  service 

This  is  the  only  portable  volume  ventilator  that's 
truly  full-featured,  giving  you  two  sigh  modes, 
backlit  LCDs, 


I;  II 


I 


variable  flow 

control-the 

latest  state-of-the-art  technology  all  the  way 

through.  And,  our  clinically  trained  support  staff  is 

available  to  you  constantly,  quickly  and  locally  in  our 


24  US  locations  and  throughout  the  world.  Our  high 
level  of  service  is  what  you  would  expect  from  the 
market  leader.  LIFECARE  Asia-Pacific  and  LIFECARE 
Europe  provide  high-level  service  in  over  40  countries. 
For  complete  information  about  the  PLV-l  02  or  our 
many  other  respiratory  products,  please  contact  us. 
I  -800-669-9234 


LIFECARE  International,  Inc. 

Westminster,  CO  •  USA 

800/669-9234  •  303/457-9234  •  Fax  255-9000 


^LIFECARE' 

State-of-the-Art  Technology  and  Superior  Service 


LIFECARE  Europe  GmbH 

Herrsching  ■  Germany 

49/8152/93  06-0  •  Fax  49/8152/93  06-18 


Circle  159  on  reader  service  card 
Visit  AARC  Booth  842  in  Orlando 

LIFECARE  Asia/Pacific  Sales  &  Service  Center  _. 

Mongkok,  Kowloon  •  Hong  Kong  ,  ™,, 

852/771  -1 886  •  Fax  852/770-7557  V3"y 


Sunday,  December  3, 3:00-4:55  pm  (Rooms  230A-B) 


LENGTH  OF  MECHANICAL  VENTILATION  FOLLOWING 
SURGERY  FOR  CONGENITAL  HEART  DISEASE    Barbara  G.  Wilson  RRT. 
Cecelia  Kuyper  MD.  Ira  Cheifelz  MD,  Frank  Kem  MD,  Jon  N.  Meliones  MD. 
Duke  University  Medical  Center,  Durham.  NC 

Outcome  data  is  essential  in  the  assessment  of  critical  care  program  quality  and 
performance.  Length  of  mechanical  ventilation  (LMV),  length  of  1CU  slay  (LOS), 
and  extubation  failures  (EF)are  major  contributors  to  cost  and  risk  associated  with 
critical  respiratory  care.    We  monitored  these  parameters  to  establish  respiratory 
care  benchmarks  for  pediatric  patients  who  have  undergone  surgery  for  congenital 
heart  disease  (CHD)    A  summary  of  this  data  is  presented.  Method:  43 
consecutive  CHD  patients,  intubated  and  ventilated  post-operatively,  were 
reviewed  retrospectively.  Patients  ventilated  <   12  hours  were  excluded.  Body 
weights  ranged  from  3  0  -  8  0  Kgs    Ages  ranged  from  1  week  to  16  months.  7 
diagnostic  groups  were  identified'    AVSD,  TOF,  TGA.  VSD,  LOB,  PA  and 
Other.  LMV  was  the  total  time  on  the  ventilator  to  successful  extubation.    LOS 
was  the  lime  from  post-op  admission  to  ICU  discharge.    EF  constituled  re- 
intubation  within  24  hours  of  elective  extubation.  Results  are  reponed  as  the  mean 
value  _+  SD.  Unpaired  t-test  and  ANOVA  were  used  to  assess  intra-group 
vas  considered  significant. 
Kxtuhation  Failures  (7/43.16%) 


differences.  A  p  <  .05  < 
Hour;     All  CHD 
LMV        81  +  76 
LOS       129+100 


206  ±  109* 
282  +  109- 


HOUR  AVSD     TOF  TGA       VSD       LOB        PA     OTHER 

LMV  44+_25  82  +  52  165+.142  75±45  244+106-  70+35       46  +  54 

LOS  70  +  48  138+_101  2I3+.158  128+.87  316+J10"  141+_39      75+77 
EF                             0/4              0/7              0/6             2/11              4/5  1/6  0/4 

(AVSD=AV  canal,  TOF  =  tetrology  of  Fallot,  TGA  transposition  of  Great 
Ateries,  VSD  =  Ventricular  Septal  Defect,  LOB  =  Left  sided  obstructive  lesions, 
PA=pulmonary  atresia.) 

Results    LMV  was  less  than  previously  reported(l).  Patients  who  failed 
extubation  had  significant  increases  in  LMV  (p=0006)*  and  LOS(p=.0007)** 
and  were  isolated  to  high  risk  CHD  anomalies.  Patients  increased  LMV  and  LOS 
<p<.05)r  Conclusions:  High  risk  CHD  diagnoses  (LOB  group)  should  be 
targeted  for  interventional  strategies  to  reduce  length  of  mechanical  ventilation, 
ICU  length  of  stay,  and  extubation  failure 
1    Chatbum  RL,  Blumer  JL.  RC  1994(39)11:1060. 


DIRECT  MEASUREMENT  VIA  AN  INLINE  PNEUMOTACH  IS 
NECESSARY  TO  DETERMINE  EFFECTIVE  TIDAL  VOLUME  IN 
CHILDREN 

Barbara  G.  Wilson.  Frank  H.  Kern.  Ira  M.  Cheifelz.  Jon  N  Meliones,  Duke 
University.  Departmenis  of  Pediatrics  and  Respiratory  Care,  Durham.  NC 

An  accurate  asscssincnl  ol  Hit-  elfccuvc  ndaJ  volume  (VTciT)  i>  essemial  to  optimize 
the  mechanical  ventilation  strategy  and  minimize  ventilator  induced  injury  in  infants 
and  children  One  method  of  estimating  the  VTeff  utilizes  vemilator  derived 
measurement  (VTefi  =  VTexpired  -  Tubing  compliance  x  (PIP-PEEP))  This  method 
may  be  limited  at  dillerunt  lunv1  compliances  and  in  ventilators  which  do  not  utilize  a 
pneumoiach  at  die  endotracheal  tube  (l-.TT)  The  purpose  of  Uns  study  was  10  determine 
if  the  VTeff  could  be  accurately  predicted  using  parameters  derived  from  internal 
ventilator  measu/erneni.s  and  known  circuit  compliance. 

METHODS:  A  Siemens  900C  ventilator  (Siemens-Elema.  Solna.  Sweden)  was 
operated  in  volume  and  pressure  control  modes  using  a  disposable  neonatal  ventilator 
circuit  (Baxter  Healthcare  Corp,  Deerfield,  II).  a  lest  lung  (Bio-TEK  Insnuments  Inc.. 
Winoosky,  VT)  and  VI  appropriate  KTT  Known  circuit  compliance  was  I  14  ml/cm 
H20  Three  VT  ranges  were  applied  in  each  mode  0-50  ml.  50-100  ml.  100-150  ml  for 

constant  Test  lung  compliance  was  I  and  1  ml/cm  H2U  A  pneumoiach  was  placed  at 
die  ETT  and  connected  to  a  respiratory  mechanics  monitor  (VenTrak.  Novametrix 
Medical  Systems.  Walhngford.  CT)  Inspiratory  (VTinspired)  and  expiratory  udaJ 
volumes  (VTexpired)  were  recorded  from  die  VenTrak  and  die  900C.  VTeff  was 
calculated  using  900C  data  The  VenTrak  VTeff  was  compared  to  VTinspired.  VTexpired 
and  die  calculated  VTeff  of  die  ventilator  Measurements  were  compared  using  linear 
regression   Maui  is  presented  lor  Vcnluk  V  |.-n  ,i>  iuiiip;in.-d  U>  vcnlilatnr  derived  VTeff 


Vi> 

ume     l.imilc 

1 

VTeff 

r 

Slope 

lolercep. 

l-sn  ml 

8X 

oil 

4  7 

SO- 100  ml 

,95 

811 

4  < 

100-150  ml 

31 

39 

5  1 

Pressure   Limited 

M0  ml 

IS 

62 

8  2 

50-100  ml 

gg 

X6 

12 

100-150  ml 

■16 

Bl 

4  0 

RESULTS   There  was  ;i  significant  difference  between  VenTrak  and  ventilator 

calculated  VTeff  (p=0 1)001)  Despile  an  adequate  correlation  at  certain  VTS.  die 
"goodness  Ol  fit"  vs.ls  poor  throughout  as  ilcmonsiniled  hy  die  deviation  of  die  slope 
from  1,  a  lack  of  B  consisteni  slope  over  a  range  of  VTs  and  the  varying  intercepts 
These  relationships  were  similar  for  VenTrak  VTeff  vs  V  finspired  and  VTexpired 
Therefore,  an  accurate  prediction  ol  die  VTeff  can  not  he  made  using  ventilator 
derived  measurements.  To  optimize  the  mechanical  ventilation  strategy  and 


n. Ml. ii, 


ich  is  required  i 


.  .mil  Lhllllllll 


sing  i 


THE  PROGNOSTIC  IMPLICATIONS  OF  A  FAILED  WEANING 
ATTEMPT.  Jennifer  E  Anderson  RRT.  N  Lennard  Specht,  MD, 
Schools  of  Allied  Health  Professions  and  Medicine,  Loma  Linda 
University,  and  Jerry  L.  Pettis  Memorial  VA  Medical  Center,  11201 
Benton  Street,  Loma  Linda,  CA  92354 

Several  scoring  systems  have  been  developed  to  predict  the 
outcome  of  patients  requiring  intensive  care  Scores  are  typically 
based  on  physiological  variables  Patients  with  respiratory  failure 
requiring  long  term  mechanical  ventilation  (MV)  have  a  higher  mortality 
than  patients  requiring  MV  for  shorter  periods  of  time.  To  evaluate  the 
prognostic  impact  of  the  success  or  failure  of  the  initial  weaning  attempt 
in  patients  requiring  short  term  mechanical  ventilation,  we  undertook  a 
prospective  trial.  Patients  who  required  mechanical  ventilation  for  5 
days  or  less  were  entered  into  the  study  if  they  consented  to  the  study 
and  were  candidates  for  resuscitation  attempts  in  the  event  of  a  cardiac 
arrest.  Pulmonary  mechanics  were  measured  prior  to  initiating 
weaning.  A  weaning  trial  was  attempted  if  two  of  the  following  weaning 
parameters  were  met:  peak  inspiratory  pressure  <  -20  cm  H20, 
respiratory  rate  <  35/min,  tidal  volume  >  5cc/kg  (ideal  body  wt.(IBVV)), 
vital  capacity  >  10  cc/  kg  (IBW)  Weaning  trials  were  standardized  and 
lasted  4  hours  Patients  were  randomized  to  receive  either  intermittent 
T-piece  trials  or  progressive  reductions  in  pressure  support  level.  A 
weaning  trial  was  considered  a  success  if  the  patient  did  not  require 
mechanical  ventilation  for  24  hours  after  completing  the  weaning  trial. 
A  total  of  67  patients  began  weaning  trials.  The  technique  used  to 
wean  the  patients  did  not  affect  the  weaning  success  rate  or  mortality. 
Weaning  parameters  were  similar  in  the  groups  of  patients  who 
survived  compared  to  non-survivors  Forty  (40)  patients  passed  their 
first  weaning  trial  while  27  failed  their  initial  weaning  attempt.  Six  of  the 
40  patients  (15%)  who  passed  their  initial  weaning  trial  died  prior  to 
discharge  from  our  facility  Of  patients  who  failed  their  initial  weaning 
attempt  13  of  the  27  patients  (48%)  died  while  still  hospitalized 
(p<0  01)  The  difference  in  survival  was  most  profound  in  patients 
over  the  age  of  65  years  We  conclude  that  recently  intubated  patients 
with  respiratory  failure  who  succeed  on  their  first  weaning  trial  have  a 
substantially  better  prognosis  than  those  who  fail  their  initial  weaning 
trial. 


PREDICTING  THE  WEANING  TIME  IN  POST-OPERATIVE 
CARDIOTHORACIC  SURGERY  PATIENTS 
Dulsie  Pilman  CRTT,  Melissa  Batchelor  CBTT,  and  William  Burke 
RRT,  PhD;  Veterans  Administration  Medical  Center,  and  The 
Respiratory  Therapy  Program,  School  of  Allied  Health  Sciences, 
Indiana  University  School  of  Medicine,  Indiana  University, 
Indianapolis,   IN  46202. 

background  Early  detection  of  respiratory  or  hemodynamic 
problems  in  the  post-operative  recovery  period  is  paramount  in 
minimizing  the  time  spent  in  the  ICU  by  patients  recuperating 
from  open  heart  surgery.   However,  it  is  not  known  how  commonly 
measured  respiratory  or  hemodynamic  variables  change  during  the 
recovery  period.  We  examined  the  possibility  that  routine 
measurements  made  early  in  the  recovery  period  could  be  used  to 
predict  the  patients  weaning  time.  METHODS  We  collected 
pulmonary  mechanics  and  hemodynamics  data  every  2-to-3  hours 
from  ICU  admission  to  extubation  in  13  consecutive  patients 
scheduled  to  undergo  cardiothoracic  surgery  at  the  local  VA 
Medical  Center.   Data  were  analyzed  by  dividing  the  total  time 
of  weaning  into  5  equal  time  brackets,  each  bracket  containing 
20«  of  the  patients  weaning  time  (bracket  1  contained  the  first 
20S  of  time,  bracket  5  contained  the  last  20») .  Routine 
pulmonary  mechanics  and  hemodynamics  variables  were  averaged 
within  each  time  bracket  and  analyzed  for  significance.  In 
addition,  we  defined  a  SHORT  WEAN  to  be  a  wean  that  consisted 
of  progressive  decreases  in  set  ventilator  rate  followed  by 
extubation.  Any  wean  not  following  this  definition  was  defined 
as  a  LONG  WEAN.   We  used  ANOVA  to  determine  how  routine 
mechanics  or  hemodynamics  variables  changed  across  the  time 
brackets  or  affected  WEAN  TIME.   Once  the  variables  affected  by 
the  time  brackets  or  WEAN  TIME  were  determined,  we  used 
multiple  regression  to  determine  what  variable  combinations 
could  best  predict  weaning  time.  RESULTS  The  mean  wean  times 
were  21.719.2  and  64.0127.5 
hours  for  the  SHORT  WEAN  and 
LONG  WEAN  groups,  respectively. 
Many  variables  were  affected  by 


LONG  WEAN,  (n^| 


PERCENT  Of  TOTAL  WEANINO  T 


lodel  of  the  following  form 
iculd  predict  the  hours  needed 
for  weaning  and  explained  73t 
of  the  variance  in  weaning  time,  83. 87+0. 61»HR-4 .25-PkPalv, 
where  HR  and  PkPalv  are  the  patients  heart  rate  and  peak 
alveolar  pressure  from  time  bracket  1.  CONCLUSION  During  time 
bracket  1,  patients  who  weaned  faster  tended  to  have;  a  lower 
HR,  CVP,  mean  PAP,  and  spontaneous  resp.  rate;  and  a  higher 
PkPalv,  PaO;,  and  stroke  volume. 


1172 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


Sunday,  December  3,  3:00-4:55  pm  (Rooms  230A-B) 


Bl(  ORE:  AN  EFFICIENT,  COST-EFFECTIVE,  NON-INVASIVE 
WEANING  TOOL  Theresa  Rvan  Schultz.  BA.  RRT.  P/P  Spec.  Linda 
Allen  Napoli,  BS,  RRT,  RPFT,  P/P  Spec,  Lorraine  F.  Hough,  MEd,  RRT, 
P/P  Spec,  Rodolfo  L  Godincz,  MD,  PhD,  The  Children's  Hospital  of 
Philadelphia,  Philadelphia.  PA 

PATIENT  DATA  AND  CASE  SUMMARY:  A  five  week  old  patient  with  a 
history  of  periodic  breathing  and  gastroesophogeal  reflux  was  transferred  from 
an  outlying  institution  after  a  one  week  hospitalization  She  had  developed  URI 
symptoms  and  had  increased  episodes  of  apnea  requiring  vigorous  stimulation 
and  FiOj  10  According  to  serial  blood  gas  analysis  the  patient  progressed  to 
respiratory  failure  and  required  tracheal  intubation  The  patient  was  placed  on 
pressure  pre-set  ventilation  (PIP  25,  PEEP  4,  RR  40,  Fi03  1  0),  Arterial  blood 
gas  analysis  revealed  7  29/58/73/27  The  IMV  rate  was  increased  to  50  breaths 
per  minute  and  the  patient  was  transferred  to  our  institution  within  two  hours 
The  chest  reoentenogram  obtained  in  our  Pediatric  Intensive  Care  Unit  revealed 
an  endotracheal  tube  in  good  position,  diffuse  peribronchial  thickening, 
atelectasis  at  both  bases,  right  upper  lobe  opacity  which  may  represent 
atelectasis  or  an  infiltrate,  no  pleural  fluid  The  baby  continued  on  current 
settings.  (PIP  28,  PEEP  4,  RR  50)  Fi02was  weaned  to  5  Pulmonary  Function 
Testing  done  with  the  BICORE  revealed  lung  overdistention  The  BICORE  is  a 
non-invasive  ventilation  assessment  tool  designed  for  monitoring  specific 
pulmonary  mechanics  Although  exhaled  tidal  volumes  were  within  target  range 
(8-10  ml/kg),  flow  waveform  analysis  and  pressure-volume  loops  indicated  that 
the  patient's  lungs  were  overdistended  Interpretation  of  time  constants 
demonstrated  that  lung  hyperinflation  was  related  to  insufficient  expiratory 
time.  The  decision  was  made  to  wean  the  patient  Supported  by  pulse  oximetry 
and  ventilation  assessment  via  the  BICORE,  the  patient's  preset  RR  was 
successfully  weaned  in  decrements  of  10  breaths  per  minute  The  patient  was 
extubated  and  placed  into  an  oxygen  hood  at  3  FiOjby  1330  that  same 
afternoon,  without  any  need  for  further  escalation  of  support 
SIGNIFICANCE  OF  THE  CASE:  Along  with  physical  assessment,  this 
patient  was  monitored  non-invasively  with  the  BICORE  Pulmonary  Function 
Machine  and  pulse  oximetry  These  methods  proved  to  be  an  efficient,  non- 
,  cost-effective  means  of  managing  this  patient 


PREOPERATIVE  AND  PERIOPERATIVE  PREDICTORS  OF  PROLONGED 
INTUBATION  TIME  WITH  CORONARY  ARTERY  BYPASS  GRAFT  PATIENTS- 
ScotlSlopic.  RRT,  Virginia  Beggs,  ARNP,  William  Nugent,  M.D.. 
Dartmouth  Hitchcock  Medical  Center,  Lebanon,  N.H 
Objective. -To  identify  preoperative  and  perioperative  predictors  of 
prolonged  Intubation  in  the  CABG  patient   Design.  -A  retrospective 
analysis  of  clinical  data  extracted  from  patient  charts  and  established 
hospital  data  bases.  The  study  cohort  consists  of  677  patients 
undergoing  isolated  CABG  between  April  1992  and  February  1994,  Data 
analyzed  included  patient  demographics  and  history,  angiography 
results,  Charleson  score,  surgical  priority,  comorbidity  Index,  Intra 
aortic  balloon  pump  insertion,  IV  nitroglycerin  for  management  of 
preoperative  cardiac  ischemia  within  24  hours  of  surgery,  number  of 
anastamoses.  IMA  graft  use,  total  bypass  time,  and  status  at  time  of 
discharge    Setting.  -Cardiothoraclc  ICU  In  a  regional  teaching 
hospital.  Patients. -677  patients  undergoing  CABG,  representing 
9 1  %  of  all  CABG  patients  during  that  time  period ,  Patients  whose  data 
could  not  be  reconciled  and  validated  from  chart  review  and  data  base 
comparisons  were  excluded  from  the  cohort.  Outcome  measures. - 
Total  intubation  time  for  each  patient  from  post-op  admittance  to  the 
CT-tCU  until  discharge  or  death   Main  resutts.-Cox  proportional 
hazard  models  were  used  to  Identify  variables  that  had  a  significant 
impact  on  total  Intubation  time  Univariate  analysis  showed  a  significant 
correlation  (p  s  0.05)  between  increased  intubation  time  and  Increasing 
age,  female  sex,  pump  time  >  1 10  minutes,  no  IMA  used,  Charleson 
score  i  2.0.  presence  of  CHF  during  index  admission,  emergent 
priority.  IABP  Insertion,  BSA  i  2  06,  presence  of  treated  C0PD, 
ejection  fraction  s  44R,  left  ventricular  end  diastolic  pressure  i  24 
cmH20,  and  number  of  anastamoses  i  4  Multivariate  regression 
analysis  showed  a  significant  (p  sO  05)  correlation  between  increased 
Intubation  time  and  increasing  age  (Hazards  Ratio=0  44),  female  sex 
(HR-0.80).  pump  time  (HR-0.75),  IABP  insertion  (HR-0.51).  and 
presence  of  treated  C0PD  (HR-0.63).  Cone /us ions,  -tn  a  multivariate 
model,  predictors  of  increased  intubation  time  in  the  post  operative 
CABG  patient  Include  increasing  age,  female  gender,  pump  time  i  1 10 
minutes,  IABP  insertion,  and  the  presence  of  treated  C0PD  We  believe 
a  prediction  model  can  be  developed  to  identify  patients  with  increased 
risk  of  prolonged  intubation.  Potential  medical  interventions  for  patients 
Identified  as  at  risk  could  be  then  initiated  Prolonged  Intubation  remains 
one  of  the  most  common  complications  of  open  heart  surgery 


ncs  the  FI02  stability  of  ihc  7200ae 
cccssory  and  software  package  which 
,  Carlsbad.  CA).  Methods:  We 
ililalor,  installed  with  a  7250  option, 


VALIDATION   OF  FW2   STABILITY  IN  THE  PURITAN 
BENNETT  7200AE   VENTILATOR   WITH   THE 
7250  METABOLIC  MONITOR 

K.  Knaus  Kinmnger  RCP  RPFT.  F  Wayne  Johnson  RCP  CRTT  RPFT  RCPT. 

Kathy  Jacobson  RDA.  David  Burns  MD. 
UC-San  Diego  Medical  Center.  San  Diego  California 

Introduction:  The  delivery  of  a  constant  FI02  by  mechanical  ventilation  is  essential  for  the 
accurate  measurement  of  oxygen  consumption  tV02)  for  indirect  calonmelry  measurements 
Fluctuations  in  FI02  of  0.005  can  result  in  errors  of  25%  in  measured  V02  The  use  of  an  air- 
oxygen  blender  (Browning.  Cnt  Care.  1982;  10:82)  or  mixing  chamber  (Johnson,  Resp  Care, 

1991  ;36(1 1)  1274)  (Branson.  Aspen.  1992.  Clin.  Congress  (95)  480)  in  line  on  the  inspiratory 
limb  of  the  ventilator  circuit,  has  been  recommended  as  a  method  to  stabilize  fluctuations  in 
the  variability  of  the  delivered  FI02.  Our  study  exami 
ventilator  installed  with  the  7250  Metabolic  Monitor  a 
stabilizes  the  7200ae  delivered  F102  (Puritan-Bennetl 
conducted  four  parallel  experiments  with  a  7200ae  vei 
connected  to  a  simulated  lung  model  Measurements  of  FI02  were  obtained  from  the  distal 
outlet  of  the  humidifier  using  a  1 100A  mass  spectromeier  (Perkin  Elmer.  Pasadena.  CAJ.The 
mass  spectrometer  was  calibrated  prior  to  each  use  with  a  primary  gravimetric  standard 
calibration  gas  (Scott  Medical  Products.  Plumsteadville,  PA)  Oxygen  waveforms  were  sampled 
at  50  Hz  by  a  compuicri/ed  data  acquisition  system  (Codas.  Data  Inslru.,  Akron  OH),  digitized 
and  stored  on  a  microcomputer  The  independent  component  in  our  study  was  the  type  of 
humidifier  or  device  used  in  the  inspiratory  limb  of  the  ventilator  circuit  The  dependent 
variable  was  the  measured  FI02  fluctuations  In  Method  I.  we  used  the  7200ae  ventilator  with 
wall  air/oxygen  gas  source,  bacterial  filter,  disposable  circuit,  and  Cascade  I  humidifier  Method 
II.  we  exchanged  the  Cascade  I  with  a  SCT  humidifier  Method  III,  the  humidifier  was 
eliminated  from  the  circuit  to  replicate  the  use  of  a  heat  moisture  exchanger  (HME).  Method 
IV.  using  the  same  ventilator  circuit  described  in  Method  III  an  additional  bacterial  filter  was 
placed  in  line  on  the  inspiratory  circuit  All  methods  were  tested  with  7200ac  ventilator 
settings  of  CMV.  ramp  flow  waveform,  peak  flow  60  L/mm.  PEEP  0  cm  H20,  Vt  I  000  L.  f 
of  10,  14,  18  and  FT02  of  .40.  .60.  and  .80  Results:  The  values  shown  in  the  table  reflect 
actual  fluctuations  within  and  between  each  delivered  breath  Inspired  oxygen  stability  as 
defined  is  a  fluctuation  in  FI02  less  than  0.002  (Browning.  Cnt.  Care.  1982:10:82). 

Methods:  Cascade  SCT  HME  HME/xtra  Filter 

Stability  in  FI02:  .0013  .0013  .0033  .0019 

Conclusions:  The  Puritan-Bennett  7200ae  ventilator  with  enhanced  software  provides  a  sta- 
ble FI02  across  (.21-80  range)  which  eliminates  the  use  of  external  or  in  line  devices  for  indi- 
rect calonmetry  measurements  However,  when  using  a  HME  hum idi fixation  system  our  data 
suggests  the  use  of  a  mixing  chamber  type  device  such  as  a  second  inspiratory  filter  to  provide 
a  delivered  FI02  that  is  within  acceptable  clinical  stability  of  <  .002  (Browning,  Cnt.  Care, 
1982;  10:82)  This  will  result  in  a  error  of  measured  V02  of  less  than  7%. 


IN  VITRO  VALIDATION  OF  THE  PURITAN- 
BENNETT  7250  METABOLIC  MONITOR 

F  Wayne  Johnson  RCP  CRTT  RPFT  RCPT.  Kathy  Jacobson  RDA.  K  Knaus  Kinmnger  RCP 
RPFT.  Ronda  Pmnett  CAT  David  Burns  MD   UC-San  Diego  Medical  Center,  San  Dtego, 
California 

Introduction:  We  validated  a  new  commercially  available  open  circuit  Metabolic  Monitor 
(PB7250.  Puntan-Bcnnett.  Carlsbad.  CA)  designed  as  an  accessory  to  the  PB7200ae  ventilator 
The  microprocessor- control  led  PB7250  Monitor  interfaces  pneumatically  and  electrically  with 
the  PB7200ae  ventilator  for  the  clinical  application  of  indirect  calorimeter  measurements  In 
laboratory  simulations  we  examined  whether  changes  in  PEEP.  FI02.  VE,  and  Vt  influence  the 
accuracy  of  the  measurement  of  V02  and  VC02  with  the  PB7250  Monitor  Methods:  The 
simulation  of  V02  and  VC02  was  achieved  by  infusing  known  flows  of  N2  and  C02  into  a 
constructed  lung  model.  (Damask,  Aneslh    I  %2,  ^7  213)  |  Kappagoda  Cardiovas.  Res. 
1972;6:589)  The  infusion  rates  of  the  N2  and  C02  were  kept  constant  to  assure  a  known 
predicted  value  through  a  series  of  precision  needle  valves  (Nupro  Co..  Willoughly.  OH), 
rotameters  (Fisher-Porter,  Warminster,  PA)  and  pressure  gauges  (Dwyer  Instruments.  Michigan 
City.  IN).  The  N2  and  C02  gas  flows  were  verified  volumelncally  before  and  after  each  trial  by 
a  dry  rolling  spirometer  iOHI<  >  Medn_.il  I'mduciv  Madison.  WI)  The  predicted  gold  standards 
for  V02  and  VC02  were  calculated  using  the  following  equations: 

V02=(VN2added)(FI02/I-FI02)(STPD)  VC02=  (VC02  added.(STPD). 

The  independent  measurement  ol  FI02  is  essential  to  establish  a  true  predicted  value  for  V02. 
The  FI02  was  analyzed  with  a  1 I00A  mass  spectrometer  (Perkin-Elmer.  Pasadena.  CA).  All 
simulations  were  performed  with  the  PB7200ac  ventilator  with  humidification  of  inspired  gas 
(35'C),  disposable  heated  wire  circuit,  SCT  heated  humidifier  Our  selected  lest  matrix  utilized 
modes  of  ventilation  which  included  CMV.  PC-IRV  and  Row-By  with  a  predicted  V02  and 
VC02  of  .300  Umin  (STPD)  The  CMV  settings  included  flow  waveforms  of  ramp,  square 
and  sine,  peak  now  of  30.  40.  50.  60.  L/min..  PEEP  of  5.  15  cm  H20.  Vt  .700  L;  f  of  12, 
18.  and  FI02  of  21.  40,  60  80  The  PC-IRV  settings  included:  inspiratory  pressure  of  25 
and  40  cm  H20;  I/E  ratio  of  I  1  and  2  I.  PEEP  of  0.  5,  15cmH20;fof  18  and  22  and  H02 
of  .21.  .40.  .60,  .80.  The  Flow-Bv  settings  in  a  ramp  flow  waveform  included:  base  flow/sens 
of  10/5,  5/1  L/min.  peak  flow  of  40,  60  L/min;  PEEP  of  0,  5.  15  cm  H20;  Vt  250.  800  L.  f 
of  10,  25  and  FI02  of  40.  60  Results:  The  performance  evaluation  compares  the  PB7250 
results  with  a  "gold  standard"  or  predicted  value  simulated  by  the  lung  model  The  number  and 
the  values  of  metabolic  measurements  arc  presented  in  the  table  The  mean  difference  between 
methods  (bias)  and  the  standard  deviation  of  the  differences  (precision)  show  statistical 
t  of  agreement  and  variability  i  Bland.  Lancet  1986,  Feb: 307-3 10). 


CMV 

PC--  IRV 

FLOW-BY 

300  L/mm 

300  L/min 

300  L/min 

V02   VC02 

V02     VC02 

V02     VC02 

1.77  -1.51 

304    2.42 

1.63     -.91 

2.92     1.92 

4.73      2.84 

3.80      3.42 

BIAS   % 
PRECISION 

#  of  MEASUREMENTS         720     720  400       400  56C 

Conclusion:  The  Puritan-Bennett  7250  Metabolic  Monitor  provides  a 
of  V02  and  VC02  over  a  wide  range  nl  mechanical  ventilator  settings  e 
cntical  care  patient.  Measurements  of  bias  .mil  precision  were  comparable  and  within  acceptable 
s  obtained  by  devices  currently  utilized  in  clinical  practice. 


ntered  by  the 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1173 


Sunday,  Dechmbkr  3,  3:00-4:55  pm  (Rooms  230A-B) 


Richard  P.  Branson  R-B-T..  Kenneth  Davis,  Jr..  M.D.,  and  Jay  A.  Johanrngman. 
M.O..  Oiviaon  of  Trauma  and  Critical  Cara.  Department  of  Surgery,  University  of 
Medical  Center.  Cincinnati,  Ohio 


INTRODUCTION:    Sub-acute  care  for  patients  requiring  long  term  weaning  is  a 
maior  growth  industry     We  studied  the  imposed  work  of  breathing  (WOE!  m  5 
ventilators  used  for  subacute  care.    METHODS;    We  simulated  spontaneous 
txeething  iSSBI  using  a  two-chambered  test  lung  at  three  tidal  volume  and  flow 
combinations  [200  mL  at  30  Umin,  4O0  mi_  at  60  Umin,  and  600  mL  at  90  Umin, 
and  at  0  and  5  cm  PEEP     Dunng  SSB  we  connected  the  5  ventilators  (Aequitron 
LP-6  and  LP-10,  Bird  TBird  VS.  UfeCare  PLV-102.  Puntan-Bennett  7200ae)  to  the 
experimental  chamber  in  the  IMV  mode.    A  pneumotachograph  and  pressure  tap 
were  placed  at  the  proximal  airway  and  measurements  of  pressure,  volume,  and 
flow  were  recorded  to  a  personal  computer  using  a  data  acquisition  system 
(Keithley  DAS  16).    From  these  signals  the  WOB,,  maximum  negative  pressure 
IPmax),  delay  ome  (OH,  and  pressure  time  product  (PTP)  were  calculated. 
RESULTS:    All  variables  were  significantly  lower  with  the  TBird  VS  and  7200ae. 
The  WOB,  through  the  three  home  care  ventilators  (LP-6,  LP-10,  PLV-100)  was 

Table  1  shows  data  when  VT-400  mL.  flow  =  60  Umin,  and  PEEP=»0. 


Ventilator 
LP-6 

Delay  rime 

1st 

0.63  (0.011 

(cmH.OI 

WOB 

(J/LI 

PTP 

IcmH.O/sl 

-5.9  (0.011 

0.30  10.001) 

2.3(0.011 

LP-10 

0.57  (0.011 

-3.8  10.061 

0.19  10.0021 

1.5  (0.021 

TBirdVS- 

0.23  10.02)0 

-1.6  (0.4I» 

0.012  (0.002I* 

0.13  (0.02)# 

PLV-102 

0.63  10.01) 

-6.7  (0.041 

0.35  I0.003I 

2.6  (0.021 

7200ao* 

0.46  10.06) 

-3.6  11.31 

0.07  (0.02) 

0.60  (0.061 

Pmax  =  maximum  negative  pressure;  WOB  =  work  of  breathing;  and  PTP  = 
pressure  ome  product. 

•All  values  statistically  significant  compared  to  LP-6,  LP-10,  PLV-102  (p<  0.001) 
^Statistically  significant  vs  7200ae  (p<0.01, 

CONCLUSION:    The  growing  sub-acute  care  arena  requires  a  ventilator  capable  of 
weaning  long  term  ventilatory  support  patients.    Our  data  confirm  previous  work 
demonstrating  excessive  WOBI  with  current  home  care  ventilators.   We  also 
present  a  new  ventilator  with  capabilities  similar  to  an  ICU  ventilator  (7200ae)  in  a 
package  similar  in  size  and  weight  to  a  home  care  ventilator 

OF-95-129 


MEASUREMENT  OF  THE  DYNAMIC  RAPID  SHALLOW  BREATHING  INDEX 

SW  Munroe  MS,  RRT,  JD  Zibrak  MD ,  KM  Dushay  MD,  C  O'Donnell , 

Sc.D.,  MPH,  M  Feldman  BS ,  RRT,  KG  Kendrick  BS ,  RRT, 

GF  MacDonald  MBA,  RRT,  P  Burke  MD.   Departments  of  Respiratory 

Care,  Pulmonary  Medicine,  and  Ceneral  Surgery,  Deaconess 

Hospital,  Harvard  Medical  School,  Boston,  MA. 

INTRODUCTION:   A  static  RSBI  of  <  105  and  >  105  has  been  shown 
co  be  both  a  good  positive  and  negative  predictor  of  weaning 
outcome  respectively.   We  hypothesized  that  the  dynamic  RSBI 
measured  over  the  course  of  a  weaning  trial  on  a  minimal  level 
of  inspiratory  pressure  support  (IPS)  is  a  reliable  predictor 
of  weaning  outcome.   METHODS:   We  studied  12  stable  patients 
who  were  being  considered  for  extubation.   We  measured  standard 
ventilatory  mechanics ,  the  static  and  dynamic  RSBI  on  a  minimum 
level  of  IPS.   Data  was  analyzed  for  significance  using  the 
Mann  Uhitney  test.   RESULTS:   Of  the  12  patients  studied,  7  were 
extubated  successfully  and  5  patients  failed  extubation. 
Duration  of  weaning  trials  ranged  from  1  to  U  hours  (mean  of 
5.1  hours).   All  of  the  patients  who  were  extubated  successfully 
satisfied  standard  weaning  criteria  including  a  static  RSBI  of 

<  105  and  an  average  dynamic  RSBI  of  < 105  .  Of  the  patients 
who  failed  extubation,  all  5  patients  were  unable  to  satisfy 
standard  weaning  criteria  and  had  a  static  RSBI  of  >  105.  Of 
these  5  patients,  U   patients  had  an  average  dynamic  RSBI  of 

>  105,  while  1  patient  had  an  average  dynamic  RSBI  of  67.5  but 
still  failed  extubation.   The  static  RSBI  predicted  weaning 
outcome  in  all  12  patients  (p=0.002).   The  dynamic  RSBI 
predicted  weaning  outcome  in  11  out  of  12  patients  (p=0.005). 
CONCLUSION:   In  this  small  sample  of  patients,  the  dynamic 
RSBI  was  a  reliable  predictor  of  weaning  outcome  but  not  as 
good  as  the  static  RSBI  and  standard  weaning  criteria. 


Dynamic  Bapo  S 


i  Brealhmg  index  StuOy  fRSQI) 


ESTIMATION  OF  ENERGY  EXPENDITURE  IN  CRITICALLY  ILL  INFANTS  AND 
CHILDREN   RECEIVING  MECHANICAL  VENTILATION  IN  THE  PEDIATRIC 
INTENSIVE  CARE  UNIT. 

Mohamad  F.  El-Khahb.  Div.  Pharmacology  &  Critical  Care.  Bonnie  Rosolowski,  RRT. 
Department  of  Pediatric  Respiratory  Care,  Rainbow  Babies  &  Children's  Hospital.  Cleveland, 
OH. 

INTRODUCTION:  Critically  ill  infants  and  children  requiring  mechanical  ventilation 
are  particularly  susceptible  to  malnutrition.  A  knowledge  ol  the  energy  requirements  of  these 
patients  is  essential  in  designing  nutritional  regimens  to  reduce  C02  production  during 
mechanical  ventilation   Lack  of  appropriate  nutritional  support  in  these  patients  may  add  to 
the  cffcclsofdisease  and  prolong  recovery  and  mechanical  ventilation.  OBJECTIVE:  In 
this  study  we  assessed  the  reliability  of  the  Harris-Benedict  (HB)  equation  (a  widely  used 
equation  for  estimating  energy  expenditures)  in  estimating  energy  requirements  in  children 
and  infants  in  the  Pediatric  Intensive  Care  Unit  (P1CU).  METHOD:  We  retrospectively 
compared  the  values  of  measured  energy  expenditures  (MEE)  to  those  predicted  by  the  HB 
equation  (PEE)  for  all  PICU  patients  who  were  evaluated  with  a  metabolic  cart  from  1/1/1992 
to  3/31/1995.  Indirect  calonmctry  (ICl  was  performed  on  patients  receiving  mechanical  venti- 
lation with  R02  <  60%  and  with  no  audible  airway  airleaks.  each  patient  was  evaluated  Foi  al 
least  15-20  minutes  and  data  for  analysis  were  obtained  from  5-15  minutes  steady  state  peri- 
ods   RESULTS:  60  children  (34  males;  26  females)  with  a  mean  age  of  7  years  (range: 
Imonth-18  years)  wen  identified  and  included  in  the  study  A  total  of  77  IC  measurements 
were  performed  (44  for  males  and  33  lor  females).  Primary  underlying  diseases  were  respira- 
tory (23  paiicnLs).  cardiac  (17  patients),  neurologic  (6paiienisi.andoihers<14  patients).  MEE 
was  significantly  less  than  PEE  (47.9+19  vs.  60.4  +  38  Kcal/kg/day.  p<0.01).  Multiple  linear 
regression  analysis  performed  on  MEE  resulted  in  the  lollowing  equations: 

Males: 

MEE(KcalMay)  =  3.3  Hcighl(cm)  +  5.7  Wcight(kg)  +  75.7  Agc(years)  +  42.3         r=  0.78 

Females: 

MEE/Kcal/day)  ■  13.9  Hcighl(cm)  +9.5  Wcight(kg)  •  42.2  Agc(ycars)  -  507 


?=  0.85 


CONCLUSION:  Accurate  and  direct  measurements  of  energy  expenditure  is  recommended 
in  critically  ill  UlilAtl  and  children  receiving  mechanical  vennl.nion  in  the  PICU.  In  the  case 
ol  an  unavailable  metabolic  can.  the  above  derived  equations  should  provide  a  belter  estima- 
tion of  energy  requirements  than  the  Hams  Benedict  equation 


MUSCULAR  ACTIVITY  CONTRIBUTES  TO  THE  INCREASE  IN  OXYGEN  DEMAND 

DURING  CHEST  PHYSIOTHERAPY 

M  Kemper.  BA.CRTT.  C  llab 

c  CCRN.  MSN 

K  Horiucbi  MD,  C  Weinman  MD.  Columbia 

Presbyterian  Medial  Center. 

departments  of  Medicine,  Anclhesiology  and  Nursing,  New 

York.  NY 

Introduction:  Increases  in  02 

onsuniplion  (V02)  dunng  chest  physiotherapy   (CRT)  may  be 

due  to  both  catecholamine  sec 

elion  and  muse 

e  activity.  Out  study  examined  the  effects  of 

muscle  relaxants  on  the  physic 

logic  response  I 

o  CPT  Methods;  Ten  poslop  ventilator 

dependent  (IMV  mode) .  SICU  pis  were  studi 

d   All  pts  had  peripheral  and  pulmonary  artery 

catheters.  Thye  were  ventilated  with  the  PB  7200  (Carlsbad  CA)  and  nielabolically  monitored 

with  a  PB  7250  metabolic  mo 

itor.  Pis  undcrw 

enl  two  CPT  sessions,  before  one  a 

Vecuronium  0.07  mg/kg  and 

Midazolam  0.15 

mg/kg  combination  was  administered  and 

berfore  the  other  a  placebo  pi 

s  Midazolani.0.15  mg/kg.  The  order  was  determined  randomly 

There  were  rest  periods  before 

and  after  each  CPT  session.  Simultaneous  blood  samples  (rum 

both  catheters  were  collected 

t  the  end  of  each  rest  period  and  CPT  session. 

Results:                    REST 

CPT 

REST 

VOj        Placebo  2J64/-42 

3304/-34- 

2234/-4S 

(rnl/min)  Drag      2234/-45 

23S+/-65* 

217+/-51 

DO,        Placebo  10734/-243 

11454/-244 

872+/- 182 

(ml/min)  Drug      872+/- 182 

10524/-262* 

931+/-295 

Sv02       Placebo  75.94/-5.1 

68.6+/-S.7* 

72.647-5.6 

mmHg      Drug     72.6+Z-5.6 

76.2t/.3.2'+ 

74.S+/-4.8 

VC02      Placebo  1874/-30 

247  ♦/•43- 

184+/-36 

ml/min     Drug       1844/-36 

1644/264 

I72+/-31 

VE           Placebo   10+/-2 

13+/-5- 

10+/-2 

Umin       Drug        I04/-2 

8+/-1 

8»/-l 

PaC02     Placebo  324/-S 

36+W 

304/-4 

mmHg      Drug       30+/-4 

3S4/-6 

33*1-6 

P«02        Placebo  1394/-36 

I16+/-25" 

1364/29 

mmHg      Drug       1364/-29 

128+/-26* 

13247.31 

f                 Placebo  13+/-S 

18+/-8+ 

144/-6 

(bpm)        Drug         14*/-6 

11+/-2 

114/-2 

SBP          Placebo   129+/-2! 

ISOtMM* 

I22+/-24 

(mnihg)    Drug         1224/-24 

I5S+/-39 

1264/-24 

HR             Placebo  94+/-15 

103+/-21 

914/-16 

(bpm)       Drug       9W/-I6 

964/.  17 

924/-20 

•Dillerenl  than  rcsl(p<0.05) 

Different  when 

drug  and  placebo  compared  (p<0.05) 

Conclusion:  The  increase  in  V02  and  VC02 

aused  by  CPTwas  attenuated  by  Hie  paralyzing 

■  gent,  blood  pressure  was  un 

rfeclcd.  The  dru 

g  prevented  an  increase  in  VE  but  Ihcre  was  uo 

greater  increase  in  PaC02  lha 

n  with  placebo 

ince  the  VC02  increase  was  suppressed 

Muscle  activity  contributes  si 

bslantially  loth 

V02  increase  dunng  CPT.  Sympathetic  output 

was  unaffected  as  the  SBP  in 

enualed. 

OF-95-047 

1174 


Rhspiratory  Cari:  •  Novhmbhr  -t)5  Vol.  40  No  II 


Sunday,  December  3,  3:00-4:55  pm  (Rooms  230A-B) 


OPTIMAL  WORK  OF  BREATHING  WITH  NEGATIVE  PRESSURE  VENTILATION 
Timothy  J  Cox.  RRT,  Jokn  J  McCloskey.  M  D  ,  A  I  duPont  Institute,  Thomas  Jefferson 
Medical  University,  Wilmington.  DE  19899 

Since  us  early  use,  negative  pressure  ventilation  (NPV)  has  been  used  in  a  control  mode  for 
patient's  with  neuromuscular  disease  Recently,  it  is  bong  used  in  other  clinical  situations  such  as 
post  op  cardiac  patients  The  conventional  negative  pressure  ventilator  can  only  be  adjusted  in 
terms  of  rate  and  negative  pressure  However,  microprocessor  technology  has  led  to  the 
development  of  negative  pressure  ventilators,  such  as  the  Life  Care  NEV  100™  ,  which  allows 
for  an  assist  mode  of  ventilation  and  the  incorporation  of  exrralhoracic  positive  pressure  during 
ventilation  cycles  Titration  of  optimal  settings  with  a  conventional  negative  pressure  ventilator  is 
to  patient  comfort  and  ABGs  We  present  a  case  report  in  which  NPV  for  a  14  month  old  child 
with  pulmonary  hypoplasia  was  optimized  by  evaluating  pulmonary  mechanics  To  date  .there  is 
no  literature  on  using  pulmonary  mechanics  to  titrate  NPV 

METHODS:  The  child  was  placed  in  a  Porta  -  Lung™  with  a  Life  Care  NEV  100™  NPV 
attached  Pulmonary  mechanics  were  evaluated  using  the  Bicore  CP-100  Neonatal  Pulmonary 
Monitor       at  various  levels  of  support  Respiratory  rate  <RR),  peak  inspiratory  and  expiratory 
flow  rates  {PIFR,  PEFR),  dynamic  compliance  (CLD),  work  of  breathing  (WOB),  mean  airway 
resistance  (Rmean),  and  expiratory  resistance  (Rex)  were  obtained  for  10  breath  cycles  and 
graphed  as  follows 


-RR(bpm) 
—  •-  PIFR  (rrt/socAg) 
•—PEFR  [rrl/secAg] 
.  T?mean|cm  H20/I7sec 
»-  Re*  (cm  H20/L/iec) 
•-CLD  |rrt/H20) 
- — woe  (gm-cnVkgl 


Nee;  8.  BaseO 


Neg  12  BaseS  Neg  16  Base  5 


RESULTS:  Pressures  of -10  and  base  +5  proved  to  be  the  optimal  pressures  as  reflected  by  ! 
decrease  in  WOB,  RR.  Rmean,  Rex  and  an  increase  in  CLD  and  PIFR 
CONCLUSIONS:  NPV  was  optimized  in  this  patient  by  measuring  pulmonary  mechanics 
Validation  of  this  method  for  titrating  NPV  will  require  studying  more  patients 


RC  Protocol 
Clearinghouse 


The  AARC  now  has  a  Respiratory  Care  Protocol  Clear- 
inghouse. RCPs  interested  in  developing  therapist-driven 
protocols  (TDPs)  for  their  departments  can  turn  to  the 
information  available  through  the  clearinghouse  to  get  a 
head  start  on  the  process. 

The  clearinghouse  makes  available  more  than  100  TDPs 
submitted  to  the  AARC  by  members  from  across  the 
nation  who  have  already  instituted  these  protocols  in 
their  hospitals. 

The  protocols  have  been  divided  into  seven  packets,  most 
of  which  contain  ten  or  more  sample  protocols.  Packets 
are  available  from  the  AARC  at  *5  each  and  currently 
cover  the  following  subjects: 

•"     Patient  assessment 
•"     Oxygen  therapy 
•■     Aerosol  therapy 
•"     Volume  expansion 
•"     Critical  care 
•"     Noninvasive  monitoring 
•"     Secretion  management 
•  •  • 
American  Association  for  Respiratory  Care 
11030  Abies  Ln.,  Dallas  TX  75229-4593 
Call  (214)  243-2272  or  fax  to  (214)  484-2720 
(MasterCard,  Visa  or  Purchase  Order  accepted) 


The  1994  bound  volume  of  RESPIRATORY  CARE  is  now  available. 

Volume  39  is  bound  in  a  blue-buckram  cover  and  may  be  imprinted,  free  of 
charge,  with  your  name  or  the  name  of  your  organization.  Each  volume  is 
s40  for  current  AARC  members  and  s80  for  nonmembers.  Shipping  is  included 
for  U.S.  and  Canadian  residents. 

Available  for  a  limited  time,  the  1 988, 1 989,  and  1 990  bound  volumes  are 
discounted  to  s30  (members)  and  s70  (nonmembers).  The  1991  and  1992 
bound  volumes  are  available  for  s35  (members)  and  s75  (nonmembers). 

Orders  must  be  prepaid;  include  check,  institutional  purchase  order,  or  valid 
credit  card  number. 

3  1 994  volume  ot  s40/s80  □  1 990  volume  at  s30/s70 

□  1 993  volume  at  s40/s80  J  1 989  volume  at  s30/s70 
3  1 992  volume  ot  535/s75  □  1 988  volume  at  s30/s70 
3  1991  volume  at  s35/s75 

□  Check         ;j  Purchase  Order       O  Visa        □  Mastercard 
Exp. date 


Daedalus  Enterprises  Inc  •  PO  Box  29686  •  Dallas  TX  75229 
FAX  (214)  484-6010 


Is  a  stall 

position 

available  at 

your  facility? 

Then  why  not  recommend 

AARC  Times  to  your 

Human  Resources  Department? 

Simply  tell  them  to  call 
Jason  Pointe  at  (800)  528-1843. 

AARC  Times  has  the  best 
classified  ads  in  respiratory  care. 


Sunday.  December  3,  3:00-4:55  pm  (Rooms  230C-D) 


SYSTEM   DEAD  SPACE  (Vsyl)  AS  A  QUALITY  CONTROL 
INDICATOR  FOR  HELIUM  DILUTION  LUNG  VOLUMES 
K   While   CRTT    K   McCarthy    RCPT.      Pulmonary   Function 
Laboratory.    The  Cleveland  Clinic  Foundation,  Cleveland,  Ohio 
44195. 

We  undertook  thjs  project  to  determine  the  reproducibility  of  the 
system  dead  space    (Vsys)  measurement  that  is  calculated  when  the 
echnologist  accepts  the  stable  initial  helium  concentration  at  the  start 
of  the  measurement  of  functional  residual  capacity    We  collected  355 
system   dead    space   values   from    5   different   pulmonary   function 
analyzers  (Excel  PFT  Analyzers.  Cybermedic.  Inc  Boulder.  CO)  over 
a  twelve  month  ume  period  (convenience  sample) 

The  value.  Vsys,    which  includes  the  volume  of  the  bellows,  tubing, 
vauem  valve  and  C02  absorbent  reservoir,  is  affected  by  the  initial 
Kllows  volume,  the  amount  of  oxygen  initially  added  to  the  system, 
the  amount  of  helium  added  to  the  system  and  the  validity  of  the  initial 
lelium  reading  (true  equilibration  of  helium)  Values  that  fall  outside 
of  the  anucipated  range  of  the  expected  mean  +  2  SD  are  associated 
with  improper  bellows  calibrauon.  loose  packing  of  the  C02  absorbent 
n  its  reservoir  or  failure  of  the  circulating  blower  motor 

The    mean    (+SD)    Vsys    calculated   just    prior    to    lung    volume 
measurement  for  all  five  units  was  12  5  (10  73)  liters    The  mean  Vsys 
or  individual  units  ranged  from   12  5  to  12  7  liters  and  standard 
deviauons  ranged  from  0  14  to  0  32  liters    These  findings  are 
summarized  in  the  table  below 

Unit  1 

Unit  2 

Unit  3 

Unit  4 

Units 

All  Units 

N 

100 

137 

30 

67 

18 

352 

Mean 

12  5 

12  5 

126 

127 

126 

125 

S.D. 

0  20 

0  32 

0  11 

0  33 

0  14 

073 

We  conclude  that  Vsys  is  reproducible,  particularly  when  one  looks  at 
values  obtained  from  the  same  testing  device  We  propose  that,  when 
available.  Vsys  should  be  routinely  used  as  a  quality  control  indicator 
that  can  alert  the  pulmonary   function   technologist  to  equipment 
malfunction  and  prevent  erroneous  measurement  of  functional  residual 
capacity  by  helium  diluuon 

O 

F-95-084 

DETERMINATIONS  OF  IONIZED  CALCIUM/ELECTROLYTES  IN 
BLOOD  GAS  SYRINGES.  Virginia  M.  Haver,  Ph.D.,  William  E.  Eng, 
M.T.,  .John  D.  Hussev  MBA.  RRT.  Daniel  D  Bankson,  Ph.D., 
Sambasiva  Lakshtninarayan,  M.D.,  VA  Medical  Center,  Seattle  WA. 
Since  heparin  binds  calcium,  either  an  electrolyte  balanced  syringe  or 
one  with  minimal  amounts  of  heparin  must  be  used  to  obtain  accurate 
values  for  ionized  calcium  (ionCa),  sodium  (Na)  and  potassium  (K)  in 
whole  blood  determinations.   We  evaluated  3  commercially  available 
heparinized  syringes:  a)  Radiometer  (RD)  Smooth-E  "balanced" 
syringe  #4900  with  120IU  lyophilized  heparin  In  3  ml;  b)  Martell  (MT) 
"balanced*  syringe  #30APH  with  50  units  blended  lyophilized  lithium 
and  zinc  heparin  In  3  ml;  c)  Becton-Dickinson  (BD)  syringe,  Bard 
Parker  liqulhep  II  containing  S00  USP  lithium  heparin  in  5  ml. 
Following  Informed  consent,  blood  samples  were  obtained  from  13 
normal  volunteers  (forearm  vein)  and  8  critically  ill  patients  in  ICU's 
(arterial  lines)  into  the  heparinized  RD  and  BD  tubes,  as  well  as  a  BD 
Vacutainer  SST  gel  tube.  Whole  blood  Ionized  calcium  and 
electrolytes  were  assayed  on  a  Ciba-Comlng  Model  288  analyzer  and 
compared  with  the  corresponding  serum  specimens  from  the 
vacutainer  samples.  Results  were  assessed  by  one-way  analysis  of 
variance  (ANOVA),  using  p<0.05  as  being  statistically  significant.  The 
BD  syringe  displayed  a  statistically  significant  lowering  of  ionCa 
values  in  whole  blood  specimens,  compared  to  serum  samples  having 
no  anticoagulant  (values  decreased  by  0.1  mmol/L).  Na  and  K  values 
obtained  from  BD  syringes  were  less  affected  (<3  mEq/L  and  <0.2 
mEq/L  differences,  resp.).  The  RD  and  MT  syringes  exhibited  no 
statistically  significant  changes  In  ionCa.  Na  and  K  relative  to  serum 
(<0.02mmol/L,  <2  mEq/L  and  <  0.2  mEq/L  differences,  resp.).  Blood 
gas  determinations  (pH,  p02,  pC02)  were  not  different  with  all  three 
heparinized  syringes.  We  conclude  that  the  BD  syringe  causes  falsely 
low  ionCa  results  because  of  its  high  heparin  content.  No  clotting 
problems  were  observed  with  either  the  RD  or  MT  syringes,  despite 
their  lower  heparin  concentration.  The  latter  two  can  be  used  to 
accurately  assess  whole  blood  electrolytes  and  ionized  calcium. 


THE  pH  OF  SOLUTIONS  USED  FOR  METHACHOLrNE  CHALLENGE  DM  Laskowski 
RPFT.  MK  Kavuru  MD.  HP  Wiedemann  MD.  A  Arroliga  MD.  M  Olcksiuk  RHP.  K 
McCarthy  RCPT,  Dept  of  Pulmonary  and  Critical  Care  Medicine.  The  Cleveland  Clinic 
Foundation,  Cleveland,  OH  44195 

Methacholine  chlonde  soluuon  for  use  in  inhalation  challenge  testing  is  diluted  in 
physiologic  saline  solution  (0  90%  NaCI)  or  a  buffered  solution  of  0  50%  saline,  0  245% 
sodium  bicarbonate.  0  4%  phenol  in  sterile  water  In  order  lo  evaluate  the  pH  of  these  two 
solutions,  we  measured  pH  al  baseline  without  methacholine  chlonde  in  solution,  and  at 
five  concentration  levels  A  Fisher  Scientific  Accumel  pH  meter  (Model  3  815MP)  was 
used  It  was  calibrated  al  7  00  (+  0  01)  and  4  00  (0  01)  using  Fisher  Scientific  pH  buffer 
soluuon.  traceable  to  National  Insututc  of  Standards  and  Technology  The  physiological 
saline  solution  (Baxter  Pharmaceuticals)  has  a  pH  range  of  4  50  10  7  00  (0  05  molar)  The 
results  are  compared  in  graph  below 


Corc«nti»bon  ol  M«ih»cfoiw,»  imyml) 


The  results  show  a  uniform  deerc 
in  the  diluent  with  physiological  s 
soluuon  remains  stable 


n  pH  as  the  conccnlralion  of  mclhatholir 

,  while  the  pH  of  the  buffered  methacholine  chloride 


We  conclude  I)  The  buffeted  solution  yields  a  slable  pH  in  the  range  of  7  78  10  8  00 
2)  The  pH  of  the  non-buffered  saline  solution  vanes  with  the  concentration  of  methacholine 
chlonde  dissolved  in  soluuon  (range  3  95  lo  5  29)    3)  The  pH  of  the  buffered  solution  and 
the  pH  of  the  saline  soluuon  vary  significantly,  Ihis  variation  may  affect  the  a 
bronchial  hypcrresponsivcness 


EVALUATION  OF  TEN  BRANDS  OF  SINGLE-PATIENT  USE  PORTABLE  PE4K 
FlOW  METERS  (PPFMs)    RA  Brown.  BS.  RRT.  RPFT.  WJ  Backes.  BS.  RRT   DcDt  of 
Respiratory  Care  Services,  University  of  Wisconsin  Hospitals  and  Clinics.  Madison,  Wl, 
USA 

Introduction:  The  measurement  of  Peak  Expiratory  Flow  (PEF)  has  been  louled  as  a  reliable 
measure  of  airway  caliber,  particularly  as  it  relates  to  beta-agonist  response,  as  well  as  being 
an  acceptable  tool  lo  monitor  episodic  bronchospasm  The  Nauonal  Asthma  Education 
Program  (NAEP)  has  established  minimum  performance  recommendauons  for  PPFMs 
Numerous  brands  and  types  of  single-pauenl  use  PPFMs  hav e  been  developed  since 
publication  of  the  NAEP  recommendauons.  with  PPFM  manufacturers  staling  their 
monitonng  devices  comply  with  these  performance  recommendauons  This  study  was 
designed  to  evaluate  10  brands  of  recently  manufactured  single-pauent  use  PPFMs  for  their 
ability  lo  measure  flows,  commonly  encountered  in  clinical  pracuce.  in  an  acceptable  and 
reproducible  fashion  Methods:  10  brands  of  PPFMs  (3  monitors  /  brand)  were  studied 
PPFMs  were  positioned  approximately  4  inches  distallv  to  a  calibrated  heated  Fleisch 
pneumotachometer  Spirometer  hardware  and  software  (Medic  al  Graphics  Corporation 
rMGCI)  comply  with  1987  ATS  Spirometer  performance  recommendations  and  have  been 
validated  bv  an  independent  testing  agency    A  different  3  00  Liter  calibration  svnnge  was 
used  as  a  volume  standard  for  this  study  and  the  Spirometer  software  temperature  was  SCI  to 
37°C  The  filled  3  00  L  synngc  was  emptied  at  varying  flows  with  recovered  volumes  being 
within  <  +/-  3%  of  the  ideal  volume,  when  each  PPFM  brand  was  in-line  Each  individual 
PPFM  flow  was  evaluated,  against  the  MGC  (MGC  value  /  Brand  value),  employing  25  flow 
challenges  using  computed  Average.  Median  and  SD 
Results:  AT,t-nijtv/»'/A.-'-«-'i.(-s  in  RaeowMdRmai MGC  versus  PPFM  Brand) 

PPFM  Brand  Name 

Sid  Dev  % 

Wrjge/',, 

Median  ",, 

Astech 

74 

-3  7 

-3  3 

Assess  Low  Range 

16  7 

-3  5 

-20 

Assess  High  Range 

■I  1 

-29 

-49 

Spu-O-Flow  Low 

175 

24  6 

24  6 

Spir-1  \-i  low 

91 

85 

7  1 

MuluSpito  "The  PEAK" 

11  1 

-56 

-67 

PockctPcak 

47 

-75 

-79 

Personal  Best-Low  Range 

85 

-11  1 

-9  1 

Personal  Best-High  Range 

10  3 

-49 

-4  4 

Baxter  "The  PEAK" 

16  0 

-106 

-88 

( 

b 

1 

onclusion:  We  conclude  there  are  significant  differences  in  recovered  flows,  with  all 
rands  of  PPFMs  we  evaluated,  which  may  negatively  influence  (impact  upon)  patient 
calmcnl  regimes  and  outcomes,  when  serial  measurements  arc  evalualcd  Additionally 
irthcr  study  is  needed  lo  measure  whal  effect  repealed  (long-term!  use,  as  well  ii  the 
iflucncc  of  humidified  air,  mav  have  on  device  performance 

OF-9E 

-108 

1176 


Respiratory  Care  •  November  '95  Vol 40  Noll 


Sunday.  December  3,  3:00-4:55  pm  (Rooms  230C-D) 


EVALUATION  OF  THE  NOMS  FINGER  PHANTOM  AS  A  SI  ANDARD  FOR 
CHECKING  PLLSE  OXIMETRY  PERFORMANCE  Teresa  VoMtri  RRT  Thomas  I. 
KaJlslrom  RRT,  Robert  L.  Chatbum  RRT.  Sl  Elizabeth's  Hospital  Medical  Center. 
Youngsumn.  OH.  Rainbow  Babies  &  Childrens  Hospital  Cleveland,  OH. 

Pulse  oximeters  are  unique  among  patient  monitors  in  that  they  cannot  be  calibrated  nor 
can  calibration  be  truly  verified.  The  purpose  of  this  study  was  to  determine  if  an  inexpensive, 
commercial  device  simulaung  a  human  finger  could  produce  Sp02  measurements  that  were 
within  the  error  specifications  supplied  by  pulse  oximeter  manufacturers  METHOD:  Five 
brands  of  pulse  oximeters  w  ere  evaluated.  We  used  the  Nonm  Finger  Phantom  to  simulate 
Sp02  values  of  95^.  90^.  and  80^c.  Pulse  rate  was  simulated  by  manual  compression  of  the 
device  using  a  metronome  at  rates  of  120.  &4.  and  60  beals/min.  For  each  saturation  level,  8 
measurements  (different  probes)  were  made  at  each  pulse  rate  (n=24).  Sp02  measurements 
were  temperature  corrected.  Bias  and  imprecision  of  measurements  were  evaluated  with  t- 
and  chi-square  tests.  Inaccuracy  intervals  (lxvine,  Fromm.  Critical  Care  Monitoring.  Mosby. 
1995:29-33.)  were  constructed  to  include  95%  of  future  measurements  at  the  99%  confidence 
level.  RESLLTS:  Observed  and  manufacturer's  specified  standard  deviation  (SD,  Spec.  SD). 
observed  and  specified  mean  difference  between  measured  and  tme_values  (A.  Spec.  A): 


tV 


SP     Snec.  SD 


A       Spec,  A        p 


2.0 


Ohmeda  Oxytip 
Nellcor  D-25 
Nonm  8000K2 
BC1  Finger  Probe  302J 
Nellcor  1-20 

Inaccuracy  intervals  are  shown  below  compared  to  specified  r. 
Novametrlx  Y  Ohmeda  Oxvtlp 


<0.001 
<0.001 
<0.001 
<0.001 
<0.001 
0.445 


2.1 


<0.001 
<0.001 
<0.001 
■eO.OOl 
«0.001 
<0.001 
.-.  j  I  r  4 


\±± 


t-jXlX 


- 

-    5 

_A    5 

- 

- 

BCI 

- 

;  "B" 

5     X 

1 

- 

;±|^ 


rat 


"  80%    90%    97%  80%    90%    97%  80%    90%    97% 

CONCLUSIONS:  Simulated  saturations  show  less  imprecision  but  more  bias  than 
manufacturer's  specifications.  Inaccuracy  intervals  indicate  that  individual  measurements 
may  fall  outside  specified  values  by  chance  for  well  functioning  oximeters.  The  Finger 
Phantom  is  a  useful  tool  if  mean  values  of  repeated  measurements  are  used.  Spot  checks  with 
single  measurements  may  not  be  adequate  for  some  brands  of  pulse  oximeters. 


OXYGEN  PULSING  DEVICES:    EFFECTS  OF  DIFFERENT  FLOW 
PROFILES  ON  SIMULATED  REST  AND  EXERCISE  CONDITIONS. 
Alex  Adams  RRT  BoD  McCoy  RRT,   Peter  Bliss  BSME 
St  Paul  Ramsey  Medical  Center  St  Paul,  MN. 

It  is  well  known  that  oxygen  pulsing  devices  conserve  oxygen  use  with 
a  savings  range  of  2  1  to  7  1  depending  in  part  on  the  pulse  flow 
profiles  of  the  device    Less  well  known  is  the  effect  of  flow  profile  on 
their  ability  to  respond  to  increased  demand  such  as  an  increased 
respiratory  rate    Methods:   Using  a  Rosemount  2024  differential 
pressure  transmitter  and  a  National  Instruments  Lab  PC  data 
acquisition  system  we  measured  precisely  the  flow  profiles  of  3 
commonly  used  pulsing  devices  at  an  equivalent  of  4  LPM  setting 
(figure)  and  extrapolated  their  performance  to  an  increased  respiratory 
rate  a  simulated  exercise  (SE)  condition 


o 


Results:  At  supposedly  the  equivalent  setting  each  device  delivered 
an  FI02  different  from  each  other  and  from  the  equivalent  constant 
flow  (CF)  setting  0  34,  0  26  0  24  and  0  32  for  devices  ABC  and 
CF  respectively    Extrapolation  to  the  SE  condition  CF  FI02  fell  to 
0  26  device  A  decreased  to  0  29  while  devices  B  C  delivered  a 
constant  FI02    Conclusions:   Demand  oxygen  pulse  devices 
perform  drfferently  at  rest  and  respond  to  SE  by  retaining  FI02  better 
than  CF  oxygen    Each  pulsing  device  should  be  prescribed  and 
administered  to  meet  oxygen  saturation  goals  for  rest  and  exercise 

OF-95-162 


OLALim  AllON  Ot  MLLHPLJ..ML1ABOLR  ^  sl  EMS  frUR  I  Sk.  I.N  1HL 
PfcDlAlKil  CLINICAL  sfclTLNC 

Iimothv  (..  Lmriad>.BA.RRI.KPKI 

All  (.  hildren*  Hospital,  St.  Petersburg.  Honda 


I.MRODICIIOV    V,  ith  the  climcaJ  use  ol  multiple 
single  hospital  lac  1 1  in    it  ma>  be  necessary   based  on  availability .  to  use  a  combinai 
ol  these  devices  tor  serial  measurements  on  individual  patients    Under  these 
circumstances  it  becomes  important  to  systematically  compare  the  results  ol  these 
devices  to  some  standard  and  included  this  information  in  metabolic  stud> 
interpretations    I  his  will  provide  a  more  cohesive  uniform  longitudinal  qualm  to 
mciabolic  results 


ML  1  HOP:    1  he  conlormiry  ol  three  Metabolic  measurement  sy  stems  in  the  t  anopv 
Mode  (the  MOM  JK-Li!e  sy stems  Industries  ihe  Deltatrac -scnsormcdics  Lorp    and  il 
2WU-Scnsormcdics  Lorp  i  were  evaluated  in  a  pediatric  range  ol  use  lor  \02  and 
VC02  1 13-75  mlrrunutei  by  applying  gas  dilution  method  f-actorv  calibrated  Cole- 
Parmer  flowmeters  were  used  to  titrate  knowii  quantities  ol  t  U2  and  Nitrogen  into  a 
pediatric  Deltatrac  (,  anopv  system  connected  to  the  measuring  port  ol  each  1; 
via  wide  bore  corrugated  tubing    Flows  were  set  at  specific  levels  and  each  n 
was  calibrated  according  10  manufacturer's  recommendations  immediately  belore  each 
test  run  Once  the  metabolic  device  was  Hushed  with  the  titrated  gases  via  the  canopy 
flow  (after  steady  state  was  achieved i.  5  one  minute  measurements  ol  \<J2  and  VC02 
were  obtained  over  a  5  minuie  interval  and  averaged    At  each  level  ol  flow    an  interval 
of  data  was  obtained  on  each  instrument  while  maintaining  consistent  (lows  during  that 
interval    C anopv  flows  were  selected  to  develop  physiologic  k'.'s  and  r-e^OJ  values 
between    5  and  1% 

KLiLLIin  Statistical  analysis  using  Paired  T-Tesi  with  standard  deviation  and 
variance  of  individual  sample  intervals  on  each  instrument  were  obtained  The 
probability  ol  Conformity  with  range  of  %  Enor  for  the  Deltatrac,  MOM  jr  and 
Scnsormcdics  2vmi  were  U  vv|7  [0-5%),  0.6368  [0-299fa>,  andti  t>yt>8  (I  7-21  5%j 
respectively    Average  sample  standard  deviations  and  variances  tor  these  instruments 
wereiSD   1.01.  I  47,&  j  |7n\AR  1  1?.  2  V8.&  I  ss>  as  well 

CONCLLMONS:  Of  the  s\ stems  evaluated  tor  pediatric  metabolic  use.  the  Deltatrac 
produced  the  most  consistent  results  in  the  Canopy  mode    W  uh  the  MGMjr  and  the 
Senso medics  2vixj.  although  each  instrument  developed  stable  interval  results,  in 
general,  their  results  werealinear  their  relative  error  was  high  and  conformity  to 
standard  was  low  iupio  299fc  lower  than  evpected  valuesi    Inese  two  systems  il  used  in 
the  pediatric  setting  should  be  closely  scrutinized  lor  variations  in  calibration  routine 
and  placed  on  a  stringent  quality  assurance  regiment 


DOES    SAE1PLXB&  RATE  EFFECT  THE  RELATTTE  AGREEHEFT  07  PetC02 
HEASURED  BI  RAflAJf  AID  BASS    SPECTROflETRT? 

J  Totaro,   Jtl  6raTbeal .   CRTT ,   6B  Russell ,   HD 
Dpt   of  Anesth,    PSTJ  College  of  tfedicine ,    Hersbey,    Pa      17033 

nmODDCTTOI     Raman  Spectrometry   (RS)   and  Mass 
Spectrometry   (HS)   are  two  common  methods  used  to  measure 
respiratory  gases ,   including  end-tidal  C02   (PetC02).    Tie  bias 
between  tbese  techniques  is  effected  by  respiratory  rate   (RR) 
(Respiratory  Care  94.190-194).    fe  determined  to  test  the 
following  hypothesis,   the  bias  between  PetC02  measured  by  RS  and 
OS  will  be  minimized  by  altering  the  sampling  rate   (Samp)   of  the 
RS,    which  is  220  il/iiii  normally      HETBDDS      Using  the   method 
previously  desenned ,   a  bench  top  lung  model ,   with  C02  added , 
simulated  respiration     An  airway  connector  with  aultiple 
sampling  ports  allowed  simultaneous  sampling  by  calibrated  RS 
and  HS     PetC02  was  determined  in  triplicate  at  each  of  these 
Samp  HS   (60  ml/mm)   and  RS   (220,    156,    131,    102  ml/mm)  ,   RR  (0, 
10,    16,    28,    35,    40   bpm)    and   various  C02  levels      Data  was 
analysized  by  linear  regression,   and  ABQYA  with  Scheffe  post  hoc 
analysis      A  p  value    <    0    05  determined  significance      The  bias  and 
limits  of  agreement  were  calculated  for  each  Samp     RESULTS     60 
pairs  of   PetC02  were  collected   with  a   positive  correlation 
between  the  RS  and  OS   (r  =   0  98,   slope  =   1    07)      (All  values  are 
mean  (SD))      PetC02  ranged   from  26   6  to  54  7  mmHg  (40.5    (11    1)) 
for  RS  and  23.2  to  53.7  »mHg  (36.7   (10.2))   for  HS     The  bias 
between  RS  and  HS  was  3.83    (2    11)    wiHg     The  bias  was  effected  by 
RR,   with  significant  differences  between  RR's   10,28   (p=0   0095), 
10,35    (p=0.001),    and    10,40    (p=0    0003)      (Figure    1)    Bo  significant 
differences  were  found  between  the  different    Samp      (Figure  2) 
C0HCLUSI0HS     Altering  RS   Samp  does  not  effect   the  RS-HS  bias 
The  cause  of  this  bias  remains  unclear ,   and  may  be  due  to  the 
different  algorithms  determining  PetC02  between  the  RS  and  HS 


Figure  1 


0     10    18  28   35  » 
Respiratorg  Rate  (bpm) 


I... 

210    155    135    100 

RS  Sampling  Rate  (ml/mtn) 


Respiratory  Care  •  November  "95  Vol  40  No  11 


.177 


Sunday,  December  3,  3:00-4:55  pm  (Rooms  230C-D) 


ACCURACY  COMPARISON  OF  BEDSIDE  AND 
LABORATORY  BLOOD  GAS  ANALYZERS 

Painc.a  A.  Meyers.  RRT.  Dennis  Buig.  RRT.  Edrie  Murphy.BS.CLS. 
MBA,  Kendra  Smith,  MD.  Mark  Mamroel.  MD.  from  Infant  Pulmonary 
Research  Center,  Children's  Health  Care  St  Paul,  MN 
Introduction:  Bedside  blood  gas  monitoring  in  the  ICU  is  now  available. 
Can  these  new  devices  replace  conventional  in-  lab  analysis?  This  study 
compares  accuracy  of  two  bedside  blood  gas  analyzers  to  standard  clinical 
laboratory  measurement  in  a  neonatal  lung  injury  animal  model.  Method: 
We  evaluated  these  systems:  P-7  (Paratrend-7)  intravascular  condnuous 
blood  gas  monitoring  system  (Biomedical  Sensors,  Malvern,  PA),  StatPal 
II,  a  portable  bedside  blood  gas  analyzer  (PPG  Industries,  La  lolla,  CA), 
and  ABL  620  bench  analyzer  (Radiometer,  Copenhagen,  Denmark).  6 
newborn  piglets  were  sedated,  intubated  and  ventilated  at  an  Fi02  of  1.0. 
We  induced  lung  injury  by  repeated  saline  lung  lavage,  producing  a  wide 
variety  of  arterial  blood  gas  values.  We  placed  in  vitro  calibrated  P-7 
sensors  in  the  descending  aorta  via  carotid  artery  cutdown.  The  StatPal  II 
was  calibrated  just  prior  to  each  sample.  The  ABL  620  auto-calibrates  on 
timed  cycles.  Saving  current  P-7  readings,  we  drew  arterial  blood  samples 
for  analysis  by  StatPal  II  and  ABL,  corrected  for  body  temperature.  We 
collected  41  comparative  points.  We  analyzed  all  data  by  linear  regression; 
and  separately  analyzed  7  data  points  with  P02  values  greater  than  300  torr. 
Results:  All  three  devices  showed  good  correlation  and  slope-intercepts  for 
pH  and  PC02.  Correlation  for  P02  was  lower,  particularly  at  very  high 


ABL-   P-7 

ABL-Stat 

Stat-P'7 

PH 

r= 

0988 

0.988 

0.973 

slope 

0.944 

1.032 

0.890 

PC02 

r= 

0.991 

0  990 

0.981 

slope 

0.972 

0.954 

0.999 

P02 

(all) 

r= 

0.956 

0.983 

0.951 

slope 

0.892 

0,641 

1.361 

P02 
(>300 

r= 

0.802 

0.944 

0  698 

slope 

0674 

1.082 

0511 

Conclusion:  The  two  bedside  blood  gas  devices  we  evaluated  a 
accurate  for  clinical  management. 


:  acceptably 


VIRTUAL  ABG'S  DERIVED  FROM  NONINVASIVE  ETCO?  AND  SpOi  DATA.  Whitney 
L  Schwartz.  BA,  RRT,  Am\  Orons.  BA  the  MR1CU  Respiralor\  Care  Staff  Herbert  Patrick. 
MD    Dcpartmcnl  of  Rcspiratorv  Care  Thomas  Jefferson  University  Hospital  Philadelphia, 

PA 

Introduction  Having  previously  reported  a  method  for  predicting  PaCO;  from  ETCO3  and 
Vd/Vt  (Rcsp  Care.  1994).  we  sought  to  both  enhance  the  accuracy  of  the  predicted  PaCO;  and 
include  predicted  SaO?  using  SpO?  therein  establishing  "virtual"  ABG's  Methods  We  used 
data  from  27  paucnts  in  our  MRJCU  on  A-C  only  in  order  to  derive  the  line  relating  PaCO?  - 
ETCOj  vs.  Vd/Vt  Although  PECO3  for  Vd/Vt  was  prc\  lously  determined  using  the 
SensorMcdics  DcltaTrac.  we  now  use  a  simple  eight-liter  exhaled  gas  collection  box  which 
was  validated  against  the  DcltaTrac  (n  =  6,  difference,  mean  ±  SD.  r  0  0007  +  0  0465.  0  93) 
Derived  {PaC02  -  PETC02)  vs.  Vd/Vt 
n=27,  (  PtC02  -  PCTC02)  =  69  81  »  Vd/Vt  -  30  43 

40 

■  a-*^-""^ — 

,___jt--*--~*'~ 

— -— -"s~-""Tr^  ■ 

■          ■ 

Vd/Vt 
SpOj  measurements  were  made  using  the  bedside  Hewlett  Packard  (HP)  SaO^/Plelh  M1020A 
Model  66  with  either  a  HP  nondisposable  or  Nellcor  disposable  finger  probe  SpO?  was 
validated  against  SaGb  calculated  from  ABG's  (n  =  12.  0  0866  +  3  17.  0  67)  Using  this 
system,  virtual  ABG's  for  patients  on  A-C  were  available  throughout  the  day  following  a 
single  conventional  ABG  and  Vd/Vt  measurement  by  box  in  the  morning  Results  Data  from 
1 3  MRJCU  patients  on  A-C  were  used  for  virtual  PaCO;  and  checked  against  actual  PaCO; 
<n  =  13,0  731  +8  47.0  60)  Three  patients  had  virtual  -  actual  PaCO:  exceeding  +  5mmHg 
Virtual  SaOj's  were  checked  against  actual  SaO:  (n  =  15. -1  117  +  2  88.0  67)  All  pauents 
had  virtual  -  actual  SaO;  within  +  3%  Conclusions    1 )  Our  modified  method  for  virtual 
PaCO?  has  improved  accuracy  and  precision  by  using  a  derived  (PaCO;  -  ETCO?)  vs  Vd/Vl 
line  specific  for  a  patient  population,  i  e  .  A-C  mode  Nevertheless  the  inaccurate  virtual 
PaCO;  in  3  of  13  patients  ma\  represent  cardiopulmonary  diseases  altering  PETCO;  and 
PECO;,  identifying  patients  who  ma>  not  be  eligible  for  virtual  ABG's  2)  The  favorable 
accuracy  and  precision  of  SpO;  as  virtual  SaO;  is  not  surprising  m  our  patient  population 
Accurate  virtual  ABG's  should  prove  to  be  cost  effective  and  grcath  decrease  utilization  of 
resources  in  the  ICU 

OF-95-121 

CAPACITY  OF  THE  SERV02  OXYGEN  CONTROL  SYSTEM  TO  CONTROL  FOR  SET 
FI02  AND  FECQ2-Frank  Denruson  M.Ed  RPFT  RRT.  D.  Spencer  Brudno.  MD.  David  Lain 
PhD,  Vladimir  Kremenchugsky  PhD,  Medical  College  of  Georgia,  Augusta,  Georgia. 

Introduction  The  purpose  of  our  study  was  to  use  a  mechanical  model  to  evaluate  the  capacity  of  a 
newly  manufactured  instrument,  the  Serv02  Oxygen  Control  System  (SS)  designed  for  the  Ohio 
Care  Plus  incubator,  to  maintain  a  set  Fi02  and  clear  expired  C02  (FeC02)  during  simulated 
clinical  conditions  Methods:  For  this  evaluation,  we  constructed  a  metal  grid  within  the  incubator 
that  provided  a  framework  for  measuring  the  concentration  of  oxygen  (02%)  and  carbon  dioxide 
(C02%)  at  16  coordinants  per  3  height  levels  relevant  to  an  infant's  environment.  To  test  for  Fi02 
maintenance  during  simulated  high  inspiratory  flow  and  02  demands,  we  used  an  Egnell  Suction 
Pump  to  apply  continuous  suction  at  5  L/min  via  a  catheter  placed  in  the  incubator  During  the 
suctioning,  a  mass  spectrometer  (MS)  (Perkin-Elmer  MGA  1 100)  was  used  to  sample  gas  through 
a  3,0  m  capillary  at  each  coordinant  with  the  SS  Fi02  set  el  0  24. 0.3S.  0.55,  and  0.75, 
respectively  An  oxygen  monitor  (Ohmeda  5 1 20)  recorded  incubator  02%  in  agreement  with  the 
SS  set  Fi02  throughout  the  study.  To  test  for  C02  clearance,  4.84  %  C02  was  insufflated  into  the 
incubator  at  0  I  L/min.  No  suction  was  applied  during  the  test  for  C02  clearance.  Suction  and 
insufflation  flow  rates  for  the  two  procedures  were  measured  by  a  Timeter  RT-200  Calibration 
Analyzer  Descriptive  statistics  were  used  to  analyze  the  data  Results;  Mean  values  (n=16)  of  the 
02%  maintained  in  the  incubator  at  3  height  levels  compared  to  set  Fi02s  are  presented  in  Table 
1.  Difference  in  the  MS  measured  02%  compared  to  the  set  Fi02  was  never  greater  than  3  75% 
(eg.,  23  1  02%  versus  the  set  24  0  02%  (set  Fi02  0,24))  for  any  of  the  measurements.  There 
was  never  an  increase  in  C02%  in  the  incubator  at  any  coordinant  above  atmospheric  baseline 
(0  03%)  dunng  the  insufflation  procedure 


in 

[   10 

1.?'. 

in 

I  10 

].:"> 

1.0 

1. 10 

1  ?', 

LO 

1  10 

1  75 

? > ; 

23  7 

?i  ? 

74  1 

!•'.  ' 

14  I 

'.!') 

53.9 

54  0 

74  0 

7-1  0 

74  0 

'1 1 

(10 

0  0 

0  1 

0  0 

00 

n  0 

o  1 

0  0 

0  1 

1)  1 

0  1 

SD 

"  At  zero  level  (L0).  eas  was  sampled  at  each  coordinant  at  mattress  level, 
and  at  10  cm  (L10)  and  25  cm  (L25).  respectively,  above  that  level 

•  •  Mean  values  and  SD  for  the  1 6  coordinants  measured  ?A  each  level 
Conclusions:  According  to  research  literature,  normal  02  consumption  and  C02  production  for  a 
large  infant  should  approximate  33  mL/min  (assumed  121b  infant  and  respiratory  exchange  ratio 
(V02/VC02)  of  1  0  for  calculations)  Normal  inspiratory  flow  demand  for  an  infant  appioximates 
2-3  L/min  for  0  5  s  per  breath  To  evaluate  the  system  to  insure  that  these  demands  could  be  met, 
our  manual  model  evacuated  (consumed)  02  at  a  rate  of  1  2  to  3  75  L/min  from  the  incubator's 
environment  and  inspiratory  Dow  demand  was  continuous  at  5  L/min-  The  simulated  FeC02  was 
0  1  Umm,  approxcmulcly  3  times  normal  for  a  large  infant   Thus,  the  simulated  demands  placed 
on  the  SS  for  Fi02  maintenance  and  C02  clearance  were  very  high.  Though  further  research  may 
be  needed  for  humidification.  IcmpcTalure  control,  and  noise  production  dllri&f  operation  of  the 
fystera,  our  study  supports  its  clinical  use  with  respect  to  I- 102  maintenance  and  C02  clearance 
This  study  was  supported  by  a  grant  from  Ohmeda  Inc  and  two  of  the  authors  were  Ohmeda  Inc 
empoyees 

OF-95-181 


A  SUBJECTIVE  SCORING  TOOL  FOR  ASSESSING  REVERSIBLE  AIRWAYS 

OBSTRUCTION 

M  Snow  RPFT,   K  Kandal  RRT  and  R  Fallat  MD 

California  Pacific  Medical  Center,  San  Francisco.  California 

BACKGROUND  Comparisons  of  methods  for  detecting  Reversible  Airways  Obstruction 
(RAO)  are  commonly  made  against  spirometry  measurements  of  FEV1  and  FVC  Airway 
Resistance  (Raw.  SRaw)  is  generally  more  sensitive  for  detecting  RAO  but  without  an 
independent  quantification,  specificitv  cannot  be  assessed  Since  the  goal  of  bronchodilator 
therapy  is  to  effeel  a  change  in  respiratory  status  whichcan  be  perceived  by  the  patient,  we 
developed  a   lool  for  quantifying  a  patients    subjective  response 

METHODS:    A  Borg-type  scale  was  developed  to  pernm  a  patiem  io  seleci  a  description  of 
respiratory  status  defining  baseline  condition  as  well  as  response  to  medication    The  scale 
provides  a  seven  point  description  of  baseline  condition  ranging  from  much  worse  to  much 
better  than  average  and  medication  response  ranging  from  worse  io  excellent  response    The 
tool  was  evaluated  on  438  consecutive  patients  with  complete  PFTs  before  and  after 
adnunislration  of  albuterol  MD1  (3  puffs  l    Each  patient  subjectively  scored  baseline  status  as 
well  as  response  to  medication  and  after  testing  rescored  baseline  status  to  determine  a  change 
post  testing    Stepwise  linear  regression  and  Chi-Square  analysis  versus  subjective  scoring  was 
used  Io  assess  sensitivity/specificity  and  correlation  between  subjective  response  versus 
difference  between  starting  ending  baseline  scores 
RESULTS 

Total 


ATS    Hi       i 

Subj  Score        Definit 

Subj  Score 

Deft 

FEV1  Yes(>( 

2L&  12%) 

82 

32 

FEVI  No  CO 

2L  OR  1 2% 

IJ7 

177 

Total 

22" 
Sensitivity  36% 

200 
Specificity  ! 

SRaw  Criteri 

Subj  Score    =Definite 

Subj  Score 

Deli 

SRaw  Yes  { ;-2 

5%&  1  21 

183 

71 

SRaw  No  (<2 

••OR  1  2) 

46 

138 

Total 

220 

200 

i:    n  it. 

Sensitivity  80% 

Specificity  t 

6% 

Subjective  (End  -  Start) 

Response  to  Med  i2     

Since  airway  resistance  directlv  assesses  the  mode  of  action  for  bronchodilator,  sensitivity  and 
specificity  should  be  high  for  patient  perception  of  response    Results  strongly  correlate  with 
subjective  score    The  high  correlation  between  medication  response  and  change  during  testing 
suggests  internal  validity 

CONCLUSIONS     I     Patient  Subjective  Scoring  correlates  strongly  with  objective  response 
indices    2    Baseline  Scoring  provides  a  reproducible  criteria  foi  trending  patients  for  follow* 
ups     1    Comparisons  of  change  from  baseline  scoring  io  end  of  test  scoring  correlates  strongly 
with  subjective  response  scoring 

OF-95-192 


I7X 


Respiratory  Care  •  Novhmbhr  '95  voi.  40  No  i 


Sunday,  December  3,  3:00-4:55  pm  (Rooms  230C-D) 


URWAY  RESISTANCE  AND  LUNG  VOLUMES  ARE  VALUABLE  ADJUNCTS  TO 
SPIROMETRY  FOR  ASSESSING  REVERSIBLE  OF  AIRWAY  OBSTRUCTION 


BACKGROUND     Airway  Resistance  (Rawi  has  been  previously  been  shown  to  be  more  more 
sensitive  than  FEV1  for  delecting  reversible  airways  obstruction  (RAO land  more  strongly 
correlated  with  patient  subjective  response  to  aerosolized  bronchodilators     Since  specific  types 
of  airway  obstruction  are  predominantly  volume  rather  than  flow  responsive,  we  hypothesized 
that  the  different  mechanisms  for  increasing  resistance  in  Asthma.  Cystic  Fibrosis.  Alpha- 
1  Antitrypsin  deficiency  Emphysema  and  COPD  may  be  reflected  in  the  pattern  of  response 

METHODS  Spirometry  and  body  plethysmography  measurements  were  made  before  and  15 
minutes  after  adminslration  of  aerosolized  bronchodilators  in  208  patients  representing 
four  distinct  types  of  airway  obstruction  Additionally.  35  patients  with  no  evidence  of  airways 
obstruction  were  also  assessed  to  provide  a  control  FEV I  and  F VC  responses  were  considered 
significant  if  they  met  ATS  guidelines  of  12%  and  >  200  ml  improvement  while  Lung  Volume 
and  Raw  responses  had  to  exceed  two  standard  deviations  from  laboratory  variability  standards 

RESULTS: 


Alpha- 1 

45 

Cystic  Fib 

34 

Normal 

35 


RV/TLC 

Raw 

SRaw 

15 

54 

58 

(21%] 

(75%) 

(81%) 

5 

20 

26 

<  9%l 

(35%) 

(45%) 

(0°< 


1  1  "  o  I 


(34% 


(23°/l 


DISCUSSION:    Relanve  sensitivity  fot  FEV1  and  SRaw  are  similar  in  normal  subjects  while 
SRaw  provides  significantly  higher  sensitivity  for  all  categories    Alpha- 1  and  CF  patienls 
demonstrate  more  significant  volume  changes  in  FVC.  RV  and  RVfTLC    Alpha- 1  patients 
demonstrate  significanl  increases  in  FVC  wiih  corresponding  decreases  in  RV 


CONCLUSIONS     1     SRaw  and  Raw  provide  increased  sensitivity  in  detecting  RAO  i 
Asthmalics  and  CF  patients    2    FVC,  RV  and  SRaw  piovide  increased  sensitivity  in 
detecting  RAO  in  Alpha- 1  and  COPD  patients    3    Lung  Volumes  and  Airway  Resistar 
provide  additional  information  nol  available  from  spirometry 


LUNG  VOLUME  STABILITY  DURING  POSTNATAL  GROWTH  IN 
PRETERM  INFANTS  WITH  RESPIRATORY  DISTRESS  SYNDROME 
Mary  McGowan  RRT.  Regma  Ykoruk  CRTT,  Emidio  M  Sivieri  MS, 
Soraya  Abbasi  MD  and  Vinod  K  Bhutani  MD  Newborn  Pediatrics, 
Pennsylvania  Hospital,  Dept  of  Pediatrics.  Thomas  Jefferson  University, 
Philadelphia,  Pennsylvania  USA, 

We  measured  functional  residual  capacity  (FRC)  in  14  neonates 
(1496  ±  227g  birthweight,  31  6  ±  1  0  weeks  gestational  age)  who  had  a 
clinical  diagnosis  of  RDS,  8  of  these  were  treated  with  surfactant    A 
computerized  helium  dilution  technique  was  used  to  measure  FRC.  The 
infant  was  connected  to  the  helium  dilution  circuit  via  a  solenoid  valve 
which  was  automatically  triggered  at  end  expiration  Four  to  6  sequential 
measurements  were  used  to  obtain  a  mean  FRC  value  for  each  study 
FRC  was  measured  during  the  first  two  weeks  of  life  (early)  and  then  at 
discharge  The  mean  ±  SD  data  for  study  age,  lung  compliance  (CL). 
FRC  adjusted  to  body  weight  (kg)  and  length  (cm)  are 


study  age 

(days) 

(mUcmHjO) 

FRC 
<mL) 

FRC/kg 
(mUkg) 

FRC/cm 
(mL/cm) 

Early 

9.9  ±34 

2.33  ±0  95 

29  7  ±6.9 

20  0  ±  2  8 

068±0.15 

Discharge 

32  5  ±5  1 

2  26  ±0  41 

44  5  ±7.1* 

21.7  ±4  1 

096±0.17* 

These  data  show  stable  lung  function  (CJ  and  a  significant  <p<0  0001)* 
change  in  FRC  including  FRC  normalized  to  length  but  not  to  body 
weight  It  is  to  be  noted  that  6/14  infants  (43%)  showed  an  apparent 
-10%  decrease  in  FRC    This  decrease  may  be  suggestive  of  air 
trapping  (which  would  indicate  a  false  reduction  in  lung  volume)  and  is 
consistent  with  expiratory  airflow  limitation  previously  observed  in  some 
low  birthweight  infants  (LBW)  secondary  to  airway  barotrauma  Gradual 
increases  in  lung  volume  occur  with  post  natal  age  and  increase  with 
somatic  growth,  but  these  may  be  influenced  by  a  history  of  barotrauma 


NEURORESPIRATORY  DRIVE,  RESPIRATORY  MUSCLES  EFFORTS 
AND  MECHANICS  OF  BREATHING  IN  PATIENTS  BEFORE  AND 
AFTER  SPECIAL  TRAINING  OF  RESPIRATORY  MUSCLES 

Anatoly  P.Zilber.  M.D.Ph.D,  Elmira  K.Chikhmirzaeva,  M.D. 
Petrozavodsk  University,  Petrozavodsk,  Russia 

Pathogenesis  and  clinics  of  chronic  respiratory  failure  always  consist 
all  three  types  of  disorders  -  central  neural  regulation,  respiratory  muscles 
activity  and  respiratory  mechanics,  but  only  respiratory  mechanics  tests 
are  used  in  routine  clinical  practice  of  respiratory  medicine. 

We  studied  55  patients  with  chronic  respiratory  failure  due  to  chronic 
obstructive  pulmonary  diseases  (COPD)  and  41  normals,  using  the  original 
noninvasive  method  of  simultaneous  investigation  of  neurorespiratory  drive 
(Pioo  and  PIOr/V).  inspiratory  and  expiratory  muscles  efforts  (P„,U1  mip 
and  P  exp)  as  the  mouth  occlusion  pressure  during  whole  inspiration 
and  expiration  as  well  as  respiratory  mechanics  (maximal  expiratory  flow- 
volume  curve  parameters,  respiratory  resistances  and  other  tests).  The 
method  was  worked  out  on  the  basis  of  lung  computer  by  common 
principle  and  simultaneous  procedure  of  occlusion  pressure  measurem 
18  patients  were  investigated  during  half  a  year  special  training  prog; 
spiralory  muscles  with  using  different  artificial  aerodyi 


iured. 
us  ,  changed 
time  PIO0  dt 
ig  an  improvt 
melioration  c 
ty.  There  is 


tances.  The  consumption  of  oxygen  by  respiratory 

The  results  showed  that  after  one  month  of  training  P, 
from  64,8±7,92  to  77,7±8,3  cm  H,0  (M±m).  In  the  sarrn 
creased  from  5,94+0,52  to  3,61  ±0,5*8  cm  H20,  demonstrati 
mem  of  the  neurorespiratory  drive  as  the  reflection  of  ; 
inspiratory  muscles  strength  and  small  airways  conductiv 
quite  good  correlation  between  changes  of  all  th 
respiratory  drive,  respiratory  muscles  efforts  and 

The  training  during  next  2  months  improved 
Next  3  months  of  training  (that  is  half  a  year) 
improvement  of  all  functions. 

The  measurement  of  oxygen  consumption  by  rt 
ing  the  training  provides  to  modulate  the  regime 

Thus  the  special  training  of  respiratory  muscle 
and  expiratory   muscles  efforts,  decreased  P,0f(  and   P|ot/^   a°d  ar 
rated  small  airways  conductivity. 

The  method  of  simultaneous  evaluation  of  3  components  of  cf 
respiratory  failure  is  noninvasive,  very  informative  and  can  be  usee 
great  success  in  functional  investigation  of  COPD  patients  as  well 
control  of  respiratory  care  effectivity. 


espiratory  mechames. 
,11  indices  by  5-10%. 
>ives  an  insignificant 

piratory  muscles  dur- 
of  training. 

proved  inspiratory 


Don't  miss  the 

Research 
Symposium 

at  the  1995 

Annual  Convention 

of  the 

American  Association 

for  Respiratory  Care 

Orlando,  Florida  •  Dec.  2-5,  1995 


Respiratory  Care  •  November  '95  Vol  40  No  11 


1179 


Monday.  December  4,  12:45-2:40  pm  (Rooms  230A-B) 


The  Effect  of  Actuation  Interval  on  Dose  Availability  with  Metered  Dose 
Albuterol 

J  L  Rau.  Ph  D  .  RRT,  Georgia  State  University,  Ruben  D 
Restrepo.  M  D  ,  RRT,  Egleston  Children's  Hospital  of  Emory  University, 


Atla 


.  GA 


The  usual  instructions  with  metered  dose  inhalers  (MDI)  suggest  a  pause 
time  of  30  seconds  between  actuations  to  allow  adequate  refill  of  the 
metering  valve    Purpose.  This  study  examined  the  effect  of  decreasing 
interval  times  between  MDI  actuations  with  albuterol  (Proventil,  Schering) 
on  delivered  dose  from  the  actuator  mouthpiece    Methods    A  sample  of 
six  unused  MDI  canisters  of  albuterol  were  selected  and  weighed  to  ensure 
comparable  fullness    Each  MDI  was  shaken  and  four  actuations  wasted 
prior  to  dose  measurements    A  Gelman  Versapor  0  45  micron,  25  mm 
filter  was  fitted  over  the  MDI  mouthpiece  of  the  actuator  using  a  one  inch 
flexible  plastic  holder    Each  MDI  was  then  discharged  twice,  at  time 
intervals  of  2,  3.  5,  10,  15,  20,  25  and  30  seconds    The  filters  were  washed 
with  5  ml  of  ethanol.  and  the  resulting  drug  solution  analyzed  by 
spectrophotometer  at  278  nm    Drug  dose  was  calculated  by  simple 
proportion,  using  a  standard  solution  of  albuterol  of  known  concentration 
Results    Mean  dose  and  standard  deviations  are  given,  in  micrograms 
Interval,  seconds 


10 


15 


20 


1858 


30 
187  6 


192  7    185  3      191  9    186  7 
SD        86  13  1         84         77  104       106        80  99 

There  was  no  significant  difference  among  the  intervals  using  a  randomized 
block,  repeated  measures  analysis  of  variance  <p=  19)    Conclusion;  Two 
actuations  of  MDI  albuterol  at  intervals  as  short  as  two  seconds  does  not 
result  in  abnormal  doses  These  results  do  not  indicate  the  possible  effect 
on  lung  distribution  with  rapid  sequential  MDI  actuations 


Effect  of  Longtcrm  Reservoir  Use  on  Dose  Availability  with  an  Inhaled  Corticosteroid 
JXJ&au.  Ph  D  ,  RRT,  Y  Zhu.  MD    Cardiopulmonary  Care  Sciences,  Ga  Stale 
University,  Atlanta,  GA  30303 

Introduction.  We  found  no  guidelines  on  length  of  use  with  reservoir  chambers,  which  arc 
usually  recommended  with  inhaled  corticosteroids  purpose.  This  study  examined  the 
effect  of  simulated  longcrm  use  of  reservoir  devices  on  dose  availability  with  an  orally 
inhaled  corticosteroid  from  an  MDI    Methods    Beclomcthasonc  dipropionatc  (Vanccnl, 
Schcnng)  was  delivered  using  three  clinically  as  ailablc  reservoirs    the  Monaghan 
Aerochamber,  the  Hcalthscan  Optihaler,  and  the  Dicmolding  Healthcare  ACE     MDI- 
rcservoir  systems  were  connected  to  one  side  of  a  dual-chambered  test  lung,  whose  other 
side  was  powered  by  an  MA-2  ventilator,  to  simulate  spontaneous  inspiration    Longterm 
use  of  the  devices  was  simulated  by  exhausting  5  MDI  canisters  through  the  reservoirs. 
Tidal  volume  -  1500  cc's,    inspiratory'  flows  =  30  Lpm  approximately  for  all  breaths 
All  oneway  valves  were  retained  in  the  mouthpieces  during  simulated  use  and  dose 
testing     In  two  separate  sencs,  one  using  cleaning  instructions,  and  one  with  no  cleaning, 
devices  from  each  brand  were  tested    Aerosol  drug  availability  at  the  mouthpiece  was 
filtered  with  cotton  and  measured  using  a  spec trophotomc trie  assay     Results.    Means 
(SD)wcre 

Optihaler        Aerochamber      ACE 

10  6  (1.2)      14  2(2  7)  10.2(3  2) 

9.5(0  5)        18.5(0  9)  7.7(2.9) 


With  cleaning  (n=3) 
Baseline,  meg 
After  5  MDI's,  meg 

Without  Cleaning  (n=3) 
Baseline,  meg 
After  5  MDI's,  meg 

A  split- plot  repeated 


119(5.4)       18  5(5  4)  7.6(2.6) 

8.7(2.0)         19  9(7  5)  8.0(3.9) 

ANOVA  revealed  that  the  brands  differed  significantly 
from  each  other  (p  =  0017),  but  with  no  significant  change  over  time  of  use  (p  =  201 1), 
with  cleaning  Without  cleaning,  brands  differed  from  each  other  (p  =  00 1 9)  with  no 
difference  over  time  of  use  (p  =  3265)  Conclusion.  The  Aerochamber.  which  adapts 
the  entire  MDI  actuator  into  the  end  of  the  reservoir,  delivered  more  CS  than  the  other 
two  brands  The  Optihaler  and  the  ACE,  both  of  which  incorporate  integral  actuators, 
tended  to  decline  in  dose  dclvicry  of  CS  over  tune  of  usage  All  brands  showed  greater 
i  dose  delivery  without  cleaning 


AIR  ENTRAPMENT  PROPERTIES  OF  THREE  BRANDS  OF  MDI  SPACER 

SYSTEMS. 

Edwin  M  Lybarqer.  RRT,  CPFT.  RCP.  El  Dorado  Hospital  &  Medical  Center,  Tucson.  Az 

An  important  aspect  of  MDI  spacer  performance  is  its  air  entrainment  characteristics 
When  a  MDI  canister  is  actuated,  a  medicinal  aerosol  cloud  Tills  the  chamber  of  the 
spacer    As  the  patient  inhales,  they  take  in  air  that  flows  through  the  holding  chamber, 
thus  inhaling  the  suspended  medication    Entrained  air  is  that  an  that  enters  the  spacer 
system  without  moving  through  the  holding  chamber    This  entrainmenl  typically  occurs  at 
the  mouth  piece  and  the  MDI  canister  stem     As  the  patient  inhales,  the  entrained  air 
mixes  with  the  air  that  has  moved  through  the  spacer  holding  chamber  at  the  time  o( 
inhalation    This  mixing  results  in  a  net  dilution  of  the  medication  in  the  volume  of  air 
inhaled  by  the  patient     METHOD     Ten  devices  each,  for  three  brands  of  spacer 
systems  were  tested  in  order  to  determine  the  percentage  of  air  entrainment    These 
brands  include  Baxter's  Hand-Held  MediSpacer,  Diemolding  Healthcare  Division's  Ace 
Aerosol  Cloud  Enhancer,  and  Monaghan's  Aerochamber     To  test  entrainment.  the 
mouth  of  the  spacer  system  is  connected  to  a  vacuum  pump    The  end  of  the  spacer  is 
connected  via  tubing  to  a  long  cylinder  of  known  radius  and  length    Knowing  the  radius, 
the  cross  section  perpendicular  to  the  length  is  determined    The  vacuum  pump  is  used 
to  create  a  flow  rate  of  30  Liters  per  minute    The  flow  rate  entering  the  end  of  the  spacer 
system  is  measured  by  periodically  dipping  the  cylinder  into  a  container  of  soapy  solution 
Bubbles  are  formed  across  the  cross  section  of  the  cylinder    These  bubbles  are  timed  as 
they  traverse  up  the  cylinder    The  velocity  of  the  bubbles  are  determined    The  velocity  of 
the  bubbles  multiplied  by  the  cross  section  ol  the  tubing  is  used  to  determine  the  flow  rate 
for  the  end  of  the  spacer  system  (  measured  intake  tlow  rate)     Any  flow  rate  that  enters 
the  spacer  other  than  at  the  end  of  the  spacer  is  the  entrainment  flow  rate    Thus  the  30 
Lrter  per  minute  flow  rate  will  equal  the  measured  intake  flow  rale  plus  the  entrainment 
flow  rate     The  soap  bubble  flow  rate  measurement  system  has  minuscule  flow 
resistance  (less  than  1  mm  water  pressure  resistance  at  30  Umm)     Thus  the  spacer 
system  is  not  disturbed  by  the  flow  rate  measurement  made      RESULTS:    There  was  a 
significant  difference  in  the  air  entrainment  flow  rates  for  the  three  brands  of  spacers 
tested  (Ace  191±6L/mm,  Aerochamber   12  0±  6  L/mm,  Hand  Held  MediSpacer  6  5±  7 
L/mm     Average  t  standard  deviation,  u  =  001    p<2E-10) 
CONCLUSION: 
The  Hand  Held  MediSpacer 
exhibits  the  least  amount  of  air 
entrainment  (leakage)  with  the 
highest  amount  of  air  How  thru  the 
chamber    Therefore  having  the 
lowest  amount  of  dilution  of 
medication  per  volume  of  air 

llltl.llcrl 


.Az 


An  important  aspect  of  MDI  spacer  performance  is  its  air  flow  resistance  characteristics 
The  air  flow  resistance  affects  the  ease  of  use  for  a  given  spacer  product    High  flow 
resistance  leads  to  the  situation  where  the  patient  must  work  harder  to  exhale  through 
the  spacer  system,  and  inhale  through  the  spacer  system    For  the  situation  of  low 
resistance,  the  patient  will  inhale  and  exhale  through  the  spacer  system  with  ease 
These  characteristics  of  a  spacer  system  turn  out  to  be  very  important  for  a  patient 
suffering  from  some  form  of  respiratory  illness     Such  a  patient  already  has  difficulty 
breathing.   The  added  resistance  of  a  spacer  systems  adds  to  the  difficulty  when 
inhaling  or  exhaling  through  Ihe  spacer  system   METHOD:   Ten  devices  each,  (or  three 
different  brands  of  spacer  systems  were  tested  for  inhalation  resistance  and  exhalation 
resistance  These  brands  are  Baxter's  Hand-Held  MediSpacer,  Diemolding  Healthcare 
Division's  Ace  Aerosol  Cloud  Enhancer,  and  Monaghan's  Aerochamber  (new  model 
with  clear  body)  To  test  inhalation  air  flow  resistance,  the  mouth  piece  of  the  spacer 
system  is  connected  to  22mm  diameter  tubing  connecting  to  a  tlow  meter    The  other 
end  of  the  flow  meter  is  connected  to  vacuum    The  vacuum  is  ad|usted  so  that  it 
creates  an  inhalation  flow  rate  of  30  L/mm     A  manometer  is  connected  via  a  Tee 
adapter  to  the  flow  meter  -  spacer  system  tubing    The  reading  of  this  manometer  is  the 
difference  in  pressure  for  the  atmosphere  and  Ihe  inside  of  the  tubing    This  represents 
the  inhalation  flow  resistance    To  test  exhalation  air  flow  resistance,  the  mouth  piece  of 
the  spacer  system  is  connected  to  22mm  diameter  tubing  connecting  to  a  flow  meter 
The  other  end  of  the  flow  meter  is  connected  to  positive  pressure  source    The  positive 
pressure  source  is  adjusted  so  that  it  creates  an  exhalation  flow  rale  of  30  Umm     A 
manometer  is  connected  via  a  Tee  adapter  to  the  flow  meter  -  spacer  system  tubing 
The  reading  of  this  manometer  is  the  difference  in  the  inside  of  the  tubing  pressure  for 
the  atmosphere  and  the   pressure  for  the  atmosphere     RESULTS:   There  was  a 
significant  difference  in  the  inhalation  flow  resistances  for  the  three  devices  tested 
(  Ace   1  94±  20  cm  H20.  Aerochamber   1  36±  1 1  cm  H20,  MediSpacer    7±  1  cm 
H20  Average  ±  standard  deviation)    There  also  was  a  significant  difference  in  the 
exhalation  flow  resistances 
tor  the  devices  tested  (Ace 

8.2±  4  cm  H20,  __airfl_ow  resistance  a  ao  i/min 

Aerochamber  36  4±10  cm 
H20,  MediSpacer    7±  1  cm 
H20:  Average  ±  standard 
deviation)     CONCLUSIONS: 
The  Hand  Held  MediSpacer 
exhibits  the  least  amount  of 
resistance  during  inspiration 
and  expiration,  therefore 
indicating  that  it  is  Ihe  spacer 
that  would  be  easiest  for  the 
patient  to  breath  through 


BS=v|f 

Ui        ^&i. 

fk 

I80 


respirators  Care  •  November  '95  voi.40Noii 


Monday,  December  4,  12:45-2:40  pm  (Rooms  230A-B) 


ElTeci  of  Multiple  MD1  Actuations  on  Dose  Aiailabihty  from  a  Spacer 

J  L  Rau.  Ph  D  ,  RRT.  Georgia  Stale  University,  Ruben  D  Restrcpo,  M  D  , 
RRT.  Eglcston  Children's  Hospital  of  Emor>  Uni\crsit>.  Vnav  Dcshpandc.  M  S  . 
RRT.  Georgia  Slate  University,  Atlanta,  GA 

Differences  in  inhalation  technique  with  reservoir  or  spacer  devices  mav  affect  MDI 
dose  availability  to  a  patient  Purpose,  This  study  examined  tbc  effect  of  single 
versus  multiple  actuations  of  a  metered  dose  inhaler  (MDI)  into  reservoir  devices  on 
doscdclncp.  of  albuterol,  with  three  climcalK  available  reservoir  brands  Methods.. 
One  side  of  a  dual -chambered  lest  lung,  whose  other  side  was  powered  by  an  MA-2, 
simulated  inspiration  from  Ihc  MDl-rcscrvoir  system  Albuterol  (Provcntil,  Schenng) 
was  delivered  bv  MDI.  with  ihc  Monaghan  Acrochambcr.  the  DHD  ACE,  and  the 
Schenng  InspirEasc.  using  standardized  volumes  and  inspiratory  flows  of  30  Lpm 
Six  samples  of  each  brand  were  tested  The  MDI  was  actuated  into  each  brand  of 
reservoir  one.  two  or  three  limes  in  rapid  succession  (two  scconsds  apart),  followed 
by  a  single  inhalation  Aerosol  dose  al  ihc  reservoir  mouthpiece  was  captured  on  a 
cotton  filter,  dissolved  in  clhanol  and  measured  with  a  spectrophotometer  at  278  run 
Reservoir  dose  availability  is  reported  as  a  percent  of  the  dose  obtained  directly  from 
one  MDI  actuation  with  no  reservoir  attached  Results,  The  Acrochambcr,  ACE  and 
InspirEasc  delivered  a  mean  ±  SD  of  22  3%  ±  0  7%.  22  7%  ±  4  98%,  and  1 1  6%  ± 

5  3%  respectively  with  one  actuation,  compared  to  4 1  2%  ±  10  3%,  38  1%  ±  10  0% 
and  18  5"  o±  8  1%  cumulative  dose  vuth  two  actuations,  followed  by  a  breath  Paired 
t-icsts  indicated  lhat  two  pufTs  increased  the  cumulative  dose  significantly  for  each 
brand  compared  to  one  puff  (p  =  002.  p=  024.  &  p  =  004  respectively)  The  use  of 
three  actuations  did  not  significantly  increase  the  amount  of  drug  al  the  mouthpiece 
of  the  reservoir  compared  to  two  actuations,  using  a  paired  t-tcst  for  each  brand  (p  ■ 

8914.  p  -  058,  <&  p  =  077  respectively)  There  was  no  significant  difference 
between  ihe  Acrochambcr  and  the  ACE  in  dose  availability  with  one.  two  or  three 
actuations!  p  =  814).  but  both  of  these  brands  provided  significantly  more  drug  than 
the  InspirEasc.  when  tested  with  a  split-plot  repeated  measures  ANOVA  (p  =  0022 

6  p  -  0027  rcspcclncK  )  Conclusion  Maximal  aerosol  bronchodilalor  from  a  MDI- 
reservoir  was  given  bv  single  actuations  each  followed  by  a  breath  Two  rapid 
actuations  followed  by  a  breath  will  give  a  significant  accumulation  of  dose  with 
minimal  loss  compared  to  iwo  single  actuations  each  followed  by  inhalation  Three 
multiple  actuations  arc  not  recommended 


ALBUTEROL  ADMINISTERED  BY  METERED  DOSE  INHALER  WITH 
HOLDING  CHAMBER  IS  MORE  EFFECTIVE  THAN  JET  NEBULIZATION  IN 
TREATING  ACUTE  ASTHMA  IN  CHILDREN 

Billy  M  Lamb  BS.  RRT.  CPFT.  Albert  Nakamshi  MD,  Edmond  Smith  MA.  RRT. 
RPFT,  Bruce  K  Rubin.  MD,  FCCP.  Saint  Louis  University  Department  of  Pediatrics  and 
Cardinal  Glennon  Children's  Hospital.  St  Louis.  MO 

INTRODUCTION  Studies  of  acute  asthma  in  adults  suggest  that  the  dose  of  albuterol 
needed  for  optimal  bronchodihtation  is  2-12  times  greater  if  medication  is  given  bv  jet 
nebulizer  (JN)  than  by  metered  dose  inhaler  with  holding  chamber  (MDI-HC)    The  use  of 
MD1-HC  rather  than  JN  results  in  a  cost  savings  for  the  respiratory  care  services    As 
there  are  few  pediatric  data  comparing  MDI-HC  therapy  with  JN  we  conducted  a 
randomized,  placebo  controlled  study  in  30  children  (age  6-12  years)  who  required  therapy 
for  acute  asthma    We  hypothesized  that  MDI-HC  is  as  effective  as  JN  for  administering 
albuterol  to  children  for  acute  asthma    METHODS  After  measuring  pulmonary  function 
(PFT)  and  obtaining  informed  consent,  children  were  randomized  into  one  of  two  treatment 
groups,  albuterol  (30  meg/kg-  up  to  I  5  mg)  administered  by  MDI-HC  using  an 
Aerochambcr  (Monaghan  Medical)  followed  by  placebo  JN  with  normal  saline  or  albuterol 
administered  by  JN  (0  15  mg/kg-  up  to  5  mg)  followed  by  MDI-HC.  1  puff  (actuation)  per 
5  kg  (maximum  15  puffs)     Ten  minutes  after  each  treatment,  the  child  completed  a 
side-effects  questionnaire  and  repeated  PFT    Each  child  had  two  sets  of  assigned  therapy 
PFT  were  performed  using  a  PC  based  MultiSPIRO-SX™  (MultiSPIRO.  Inc  Irvine.  CA) 
RESULTS  Patients  treated  with  MDI-HC  were  less  tired  and  had  greater  tremor  when 
compared  to  those  treated  with  JN  (X;  p  <  0  05)    Linear  regression  on  log  albuterol  dose 
over  the  maximal  response  range  of  a  40-60%  improvement  in  FEV,  suggested  that  12 
times  more  medication  was  required  using  JN  to  achieve  a  40%  improvement  in  FEV,   and 
4  times  more  was  needed  to  achieve  a  60%  increase  with  a  mean  of  7  7  times  more  by  JN 
over  this  range    More  than  75%  of  the  bronchodilation  was  obtained  after  the  first  active 
treatment  with  either  JN  or  MDI-HC  There  was  a  significant  placebo  effect  associated 
with  the  use  of  saline  by  JN  in  that  children  reported  that  they  could  breathe  more  easily 
despite  the  lack  of  change  in  PFT    No  such  effect  was  noted  with  the  use  of  placebo 
MDI-HC     Our  cost  for  delivery  of  albuterol  by  JN  therapy  are  $8.56  for  set  up  and 
$5  68  per  treatment  (includes  RCP  time,  meds  and  all  supplies),  cost  for  albuterol  therapy 
with  MDI-HC  are  $18  32  set  up  and  $2  13  per  treatment  (includes  RCP  time,  meds  based 
upon  6  puffs/treatment  and  holding  chamber)  Based  upon  a  model  of  the  patient  receiving 
set  up  and  two  treatments  in  the  emergency  room,  then  Q4  hour  therapy,  MDI-HC  results 
in  a  $  1 8  64  savings  after  the  first  24  hours  and  $2 1  38  per  day  thereafter  At  the  #3 
treatment  interval,  MDI-HC  cost  were  $24  71  and  JN  cost  were  $25  60    CONCLUSION 
These  data  support  the  use  of  albuterol  given  by  MDI-HC  in  the  treatment  of  acute  asthma 
re  treatments  arc  required,  MDI-HC  therapy  is  more  cost 
of  acute  asthma  in  children 
i  Medical  Corporation, 

OF-95-076 


in  children    When  three 
effective  than  JN  for 
Supported  by  hionagh 


ALBUTEROL  AEROSOLIZED  BY  ULTRASONIC  NEBULIZER  IS  LESS 
EFFECTIVE  THEN  JET  NEBULIZATION  FOR  THE  TREATMENT  OF 
ACUTE  ASTHMA  IN  CHILDREN 

Billy  M  Lamb  BS.  RRT.  CPFT.  Bruce  K  Rubin  MD,  FCCP,  Albert  K  Nakanishi 
MD.  Charles  Foster  BA,  RRT,    Cardinal  Glennon  Children's  Hospital  and  St 
Louis  University  Dept  of  Pediatrics.  St  Louis,  MO 

INTRODUCTION     A  study  of  adults  with  stable  asthma  suggested  that  albuterol  given  by 
ultrasonic  ncbulizauon  (UN)  was  more  effective  than  die  same  dose  of  albuterol  given  by  jet 
nebuhzaiion  (JN)    Considering  nebulization  umc  using  an  UN  is  half  of  the  ume  required  using 
a  JN  for  an  equal  volume  of  medicauoa  we  hypothesized  thai  efficacy  of  aerosolized  albuterol 
when  given  by  UN  would  be  the  same  as  for  albuterol  given  by  JN  in  producing  bronchodilllauon 
and  lhat  UN  would  represent  a  significant  cost  savings  and  a  convenience  to  the  pauenl 
METHOD  we  evaluated  125  children,  aged  7-16  years  (mean  10  5)  who  presented  for  treatment 
of  acute  mild  to  moderately  severe  asthma    After  informed  consent  and  randomizauon.  46 
children  received  albuterol  by  UN  (Microstat,  Mountain  Medical)  and  67  were  treated  by  JN 
(Whisper  Jet,  Marquesi  Medical)  at  a  flow  rate  of  6-8  LPM  Dosage  of  albuterol  for  both  groups 
0  1 5  mg/kg  to  a  maximum  5  mg  diluied  in  2  cc  normal  saline  The  UN  group  were  treated  with 
nebulized  albuterol  (NA)  for  six  minutes  and  the  JN  group  NA  for  12  minutes  (JN  ume  in 
compliance  with  the  AARC  uniform  ume  standard)    Pulmonary  funcUon  testing  (PFT)  was 
performed  using  Rcspiradyne  (Sherwood  Medical.  St  Louis)    FVC.  FEV1.  FEV1  to  FVC  rauo, 
PEFR  and  FEF25-75  were  recorded  as  outcome  measures  30  minutes  following  iniUaUon  of  NA 
for  both  groups  Only  paUents  with  an  initial  percent  predicted  FEV1  of  70%  or  less  were 
admitted  to  the  study    Side  effects  and  uemor  were  documented  Exclusion  Criteria  patients 
requinng  assisted  venulauon.  urgent  or  immediate  intervenuon,  patients  with  baseline  respiratory 
rate  >  70  breaths  per  minute,  lruual  Sp02  <  0  90.  or  if  intolerant  of  beta  agonist  medicauons 
RESULTS  PFT  on  entry  to  the  study  was  consistent  in  the  two  groups  (FEV1.  p  >  0  97)    The 
change  in  FEV1  after  therapy  (UN  +0  22  L  vs.  JN +0  37  L)  was  significant  (p  =  0  035)  and 
favored  JN     There  was  no  difference  in  the  improvement  in  PFT  between  JN  and  UN  therapy  in 
children  with  an  initial  FEV1/FVC  >75%  however,  when  initial  FEV1/FVC  <  75%.  the 
improvement  in  FEV1   favored  JN  (UN-K)  2  vs.  JN+O  47,  p  =  0  04)  There  was  a  trend  toward  a 
greater  pauenl  report  oftremor  after  JN  when  compared  to  UN  (p=  0  14)    DISCUSSION    UN  is 
reported  lo  deliver  a  smaller  particle  size  men  JN.  the  smaller  particle  size  delivered  by  UN  is 
thought  to  be  advantageous  for  the  delivery  of  medicauon  to  the  lower  respiratory  tract,  however, 
smaller  particles  may  be  more  likely  lo  be  exhaled  ralhcr  than  deposited  in  the  lower  airway 
particularly  in  tachypneic  and  distressed  patients  who  may  be  inhaling  medicauon  at  nd.il 
breathing  rather  than  taking  a  deep  breath  with  breath  hold  after  each  inhalauon    Children  with 
exacerbations  of  asthma  arc  frequenUy  tachypneic.  dyspneic,  and  have  high  inspiratory  flow 
raies.  this  can  limit  the  efficacy  of  nebulized  medicauons    CONCLUSION    This  study 
demonstrates  thai  for  trealment  of  moderately  acute  asthma  in  children,  delivery  of  albuterol  by 
UN  has  no  advantage  over  delivering  die  same  amount  of  medicauon  by  JN    As  different 
nebuhzaiion  systems  have  different  charactensucs  and  outputs,  these  data  do  not  indicate  thai  JN 
is  superior  to  UN  for  the  administration  of  albuterol  but  rather  that  the  specific  nebuhzaiion 
svstems  used  here,  under  these  test  condiuons,  did  not  support  the  use  of  UN 

OF-95-075 


BRONCHODCLATOR  THERAPY  THROUGH  AIRWAY  FOR  PATIENTS  WITH 
MECHANICAL  VENTILATION:  A  COMPARJSON  OF  3  DELIVERY  METHODS 

Mauo-Ying  Bien  MS  RPT  CRTT.  Jia-Homg  Wang  MD,  Wun-Hsiu  Chen  RT,  Wun-Jie  Hsu  RT, 
Chong-Chen  Lu  RRT  MD    Veterans  Gereral  Hospilal-Taipei,  Taiwan,  Republic  of  China 

Introduction:  Aerosolized  bronchodilators  are  commonly  administered  to  intubated  mechanically 
ventilated  pauents  by  using  a  small  volume  nebulizer  (SVN)  or  metered  dose  inhaler  (MDI)  with 
spacer    Both  methods  can  get  good  bronchodilauon  effects    In  our  insumuon,  directly  instilling 
bala-agorust  into  pauent's  artificial  airway  (INS)  in  the  emergency  condiuon  can  also  relieve 
bronchospasm  immediately    The  purpose  of  this  study  was  lo  compare  the  bronchodilauon 
effects,  side  effects  and  cost  of  these  3  methods  to  deliver  terbutaiine  in  pauents  with  mechanical 
venulauon    Methods:  Seventeen  mechanically  venulated  pauents  (12  males  and  5  females,  aged 
69  76 ±7.64  yTS)  due  to  acute  cxacerbauon  of  COPD  or  asthma,  having  order  lo  receive 
terbutaiine  inhalation  for  control  of  bronchospasm.  were  consented  to  participate  in  this  study 
Method  A  was  to  inhale  4  ml  (10  mg)  of  terbutaiine  by  SVN,  Method  B.  4  puff(lmg)  by  MDI 
with  Aerovent;  and  Method  C,  4  ml  (10  mg)  by  INS  followed  by  manual  hyperinflation    Each 
pauenl  received  3  methods  of  ueatment  on  the  same  day  at  intervals  of  at  least  4  hours    The 
sequence  of  methods  was  randomized    The  venulator  setting  was  kept  the  same  throughout  the 
study    Respiratory  rate.  Ppeak,  Pplat,  auto-PEEP.  Rinsp,  pulse  rate.  Sa02  and  BS  in  each  pauent 
were  monitored  before  and  0,  30.  60,  120  minutes  after  each  ueatment    Arterial  blood  gas  was 
analyzed  60  minutes  after  each  treatment    The  costs  of  medication,  driving  gas,  device,  and 
manpower  per  one  treatment  were  esumated  in  US  dollars  for  each  method    Data  were  expressed 
as  mean  (SD!    One-way  ANOVA  for  repeated  measures  and  Turkey's  Test  for  mulUple 
comparisons  were  used  to  compare  the  results    Results:  All  pauents  tolerated  these  3  methods  of 
treatment  well    Significant  difference  in  Rinsp  change  was  found  between  Methods  A  and  B,  A 
and  C  (p  <  0  05)  at  120  minutes  after  ueatment    Significant  difference  in  pulse  rate  change  was 
found  at  post-0.  30.  60  and  120  minutes  of  treatment  between  Methods  A  and  C.  B  and  C  (p  < 
0  05)    No  significant  difference  in  Ppeak,  Pplat.  Auto-PEEP.  RR,  SBP,  DBP.  Sa02  and  BS  at  any 
point  of  measurement.  ABG  at  post-60  minutes;  Rinsp  at  post-0.  30.  60  minutes  was  found 
among  these  3  methods    The  most  cost-  saving  method  is  B  (US$  3  03  vs  US$  11.74  in  A  and 
USS  8  54  in  C) 

Rinsp  (cmHIO/L'i)  Pul*  R»«*  (/iota) 


A                 B 

c 

Baseline        12.99(6.07)    14.02(6.76) 

3.31(7.24) 

Pou-    Omin    1.72(3.98)   -1.87(5.21) 
Posi-  30mm    1.93(5.09)    -1.43(5.14) 
Poil-  60m.n    0.66(3.94)    -1.20(6.31) 
Pou-120nun    2.83(3. 84^.2.48(6.43)" 

0.90(407) 
0.66(397) 
0.05(3  96) 
2.11(6.43)*, 

A 

B                     C 

Baseline       113.94(2 

-94)  1 

3.06(27.04)  106.24(20.16) 

Posi-     Omio    -0  18(1 

Pou-  60mi«.    -0.59(1 
Po«.120nnii   -2  41(1 

J.OO)* 
.58)- 
2.92)' 

0«(S70W  11  59(1023)1. 
0  53(9781*   2Z35U4.91S, 

0l»(9.16k-    I!71(1S.46)&, 
-188(12311,  2094(18058, 

Conclusion: 

but  requires 
due  to  drug 


difference  between  A  and  C  (P<0.05)         "  Siginflvant  difference  between  BudCuuv  poinl  (P<0.05) 

Method  B  can  achieve  at  least  the  same  bronchodilauon  effect  as  Methods  A  and  C 
the  least  cost    Method  C  can  significantly  increase  the  pauent's  pulse  rate,  probably 


Respiratory  Care  •  November  '95  Vol  40  No  11 


1181 


Monday,  December  4,  12:45-2:40  pm  (Rooms  230A-B) 


CHARACTERIZATION  OF  LIPOSOME-LADEN  AEROSOLS 
DELIVERED  BY  A  MULTIPORT  AEROSOL  CHAMBER 
Janette  M.  Waqonseller,  BS,  CRTT,  Diane  Kachel,  BS, 
and  Douglas  G.  Perry,  PhD,  RRT 

Respiratory  Therapy  Program,  School  of  Allied  Health  Sciences, 
and  Division  of  Pulmonary  and  Critical  Care  Medicine, 
Indiana  University  School  of  Medicine,  Indianapolis  IN  46202 

Introduction:  Aerosolization  of  medication  to  the  lungs  is  a 
common  procedure  in  treating  lung  disease  However, 
aerosolization  has  been  limited  to  delivery  of  water-soluble  drugs. 
A  new  form  of  drug  packaging  has  been  developed:  Liposomes  are 
drug-containing  artificial  vesicles  Aerosolization  of  liposomes  is 
emerging  as  a  promising  treatment  strategy.  To  develop  a  mouse 
model  to  study  aerosolized  liposomes,  we  investigated  the  use  of  a 
specially  designed  multiport  chamber  to  deliver  aerosols  to 
rodents  The  purpose  of  this  project  was  to  characterize  aerosols 
containing  liposomes  delivered  by  this  multiport  aerosol  chamber. 
Methods:  Aerosols  with  and  without  liposomes  were  generated  by 
ultrasonic  nebulization  and  sampled  either  directly  from  the  nebu- 
lizer or  from  a  multiport  aerosol  chamber.  Samples  were 
gravimetncally  analyzed  for  aerosol  particle  size  and  distribution 
using  a  cascade  impactor  Results:  Mass  median  diameter  (MMD) 
for  standard  aqueous  aerosols  from  the  nebulizer  and  from  the 
chamber  was  4  9  and  4  8  urn,  respectively;  MMD  for  liposome- 
laden  aerosols  from  the  nebulizer  and  chamber  was  4  2  and 
3.8  pm,  respectively.  For  each  of  the  experimental  conditions, 
aerosol  particle  size  distribution,  quantified  as  geometric  standard 
deviation  (og)  was  1.60.  1  50.  1  35,  and  1.60,  respectively 
Conclusion:  The  multiport  aerosol  chamber  had  little  or  no  effect 
on  particle  size  (MMD)  with  either  standard  aqueous  aerosols  or 
liposome-laden  aerosols  In  addition,  the  multiport  chamber  had  no 
effect  on  the  distributions  of  aerosol  particle  size.  In  contrast, 
addition  of  liposomes  in  the  aerosol  produced  a  modest  decrease 
in  particle  size  with  virtually  no  effect  on  particle  size  distribution 

OF-95-068 


PATTERN  OF  DEPOSITION  AND  AEROSOL  PARTICLE  SIZE 

IN  A  DRY  VS  HUMIDIFIED  VENTILATOR  CIRCUIT  USING 

METERED  DOSE  INHALER  AND  SPACER 

I.  Fink,  MS,  RRT,  R.  Dhand  MD,  J.  Grychowski  PhD,  M.J.  Tobin 
MD.  Hines  VA  Hospital  and  Loyola  Univ.  Chicago,  Hines  IL. 

To  determine  the  role  of  heat  and  humidity  on  deposition 
and  particle  size  during  aerosol  administration  to  ventilated 
patients,  we  administered  albuterol  by  metered  dose  inhaler 
(MDI)  with  spacer  chamber  into  the  inspiratory  limb  of  a  dry 
(27"C,  <30%  RH)  or  wet  (35°C,  >99%  RH)  ventilator  circuit.  A 
trachea  and  bronchi  model  was  ventilated  through  an  8  mm  ET 
tube  during  control  mode  (CMV).  The  mean  mass  aerodynamic 
diameter  (MMAD)(QCM  cascade  impactor  with  Plenum 
chamber)  and  albuterol  deposition  (246nm)  measured  distal  to  the 
spacer  chamber  (site  A),  entering  the  ET  tube  (site  B)  and  at  the 
bronchi  (site  C)  were: 

SiteB 

Wet       Dry 
1.1  1.3 

29.8       35.0 

At  site  A  there  was  a  significant  difference  between  wet  and  dry 
conditions  in  both  MMAD  (p<0.007;ANOVA)  and  deposition 
(p<0.001),  while  at  site  C  deposition  differed  (p<0.003)  but 
MMAD  did  not  (p=0.16).  In  summary,  during  CMv  with  heat 
and  humidity  a  larger  fraction  of  albuterol  leaves  the  spacer 
chamber  with  a  larger  particle  size,  compared  to  a  dry  circuit. 
Humidification  lead  to  a  three-fold  increase  in  the  ventilator 
circuit  resulting  in  a  decreased  albuterol  at  the  bronchi.  The 
deposition  of  drug  in  the  ventilator  circuit  under  both  wet  and  dry 
conditions  was  greater  in  the  ventilator  circuit  than  the  ET  tube 
(p<0.001). 

In  conclusion,  compared  to  a  dry  ventilator  circuit, 
humidification  resulted  in  a  larger  MMAD  with  reduction  in 
bronchial  deposition. 

OF-95-157 


Site  A 
Wet       Dry 
MMAD  urn  1.6        1.3 

Deposition  %       60.5      44.8 


SiteC 
Wet      Dry 


16.0    30.3 


DETERMINATION  OF  REGIONAL  VENTILATION  IN  MECHANICALLY 
VENTILATED  PATIENTS:  USEFULNESS  OF  ""TC-DTPA  AEROSOL  -- 

Corazon  J  Cabahug  MD,  Michael  McPeck  RRT  Lucy  B  Palmer  MD,  Ann 
Cuccia  RRT,  Harold  L  Atkins  MD  &  Gerald  C  Smaldone  MD  PhD     Depart- 
ments of  Radiology,  Respiratory  Care  &  Medicine,  SUNY  at  Stony  Brook 

In  spontaneously  breathing  patients,  previous  investigators  have 
claimed  that  regional  ventilation  (RV)  can  be  estimated  by  deposition  images 
following  inhalation  of  radiolabeled  aerosols  The  goal  of  this  study  was  to 
determine  the  usefulness  of  radiolabeled  aerosols  in  the  assessment  of  RV  in 
tracheotomized  patients  maintained  on  mechanical  ventilation    Methods 
First,  prior  to  clinical  studies,  3  commercially  available  radioaerosol  nebulizer 
kits  were  studied  on  the  bench  to  determine  nebulizer  efficiency  and  particle 
distribution  of  "Tc-DTPA  aerosols  Then,  using  a  gamma  camera,  we  studied 
5  ventilated  human  subjects  and  simultaneously  measured  RV  with  B""Kr  gas 
and  Tc-DTPA  aerosol  Images  were  compared  visually  and  by  analysis  of 
radioactivity  distributions  in  computer-generated  regions  of  interest  Results 
Although  its  Inhaled  Mass  %  was  not  as  great  as  the  Aero  Tech  I,  we  found 
that  the  UltraVent  system  produced  the  smallest  particles  with  a  mass  median 
aerodynamic  diameter  of  0  9  pm  compared  to  the  AeroTech  I  and  VentiScan  II 
systems  which  both  produced  aerosols  of  1  3  urn  In  spite  of  the  relatively 


Nebulizer  Tested 

Mean  Inhaled  Mass  % 

MMAD  (pm) 

Mallmckrodt  "UltraVent" 

21  15  ±2  13SD 

0  9   ±  1  67  (og) 

BioDex  "VentiScan  II" 

15  50±0  11  SD 

1  3  ±  1  92  (og) 

CIS-US  "AeroTech  I" 

34  14  ±0  76SD 

1  3  ±  1  92  (og) 

small  particles,  *"Tc-DTPA  deposition  images  with  the  UltraVent  nebulizer  did 
not  accurately  represent  RV  as  measured  by  K1mKr  equilibrium  Visual 
inspection  of  images  revealed  significant  amounts  of  particle  deposition  in  the 
region  of  the  trachea  which  was  diminished  but  not  eliminated  after  replacing 
the  tracheotomy  tube  inner  cannula  Using  regional  analysis,  correlations 
between  radioactivity  distributions  of  both  isotopes  were  poor  (r  ■  0  262,  p  = 
0  162),  with  segmental  analysis  suggesting  that  the  upper  and  middle  lung 
regions  were  significantly  affected  by  residual  tracheal  activity  Conclusions 
The  lungs  of  patients  receiving  continuous  mechanical  ventilation  can  be 
imaged  after  the  inhalation  of  °°"Tc-DTPA  aerosol  from  commercially  available 
delivery  kits,  but  the  correlation  between  aerosol  deposition  and  RV  is  poor 
Better  definition  of  ventilated  lung  segments  is  obtained  when  using  a  gas 
such  as  B,mKr  because  tracheal  activity  with  the  radiolabeled  gas  is  minimized 
RCPs  should  be  familiar  with  these  techniques  in  the  event  they  must  assist 

OF-95-194 


PERFORMANCE  EVALUATION  OF  THE  HEART  CONTINUOUS 
NEBULIZER  --  Michael  McPeck  RRT.  Ravi  Tandon  MD,  Kenneth 
Hughes  RRT  and  Gerald  C  Smaldone  MD  PhD    Departments  of 
Respiratory  Care  and  Medicine,  SUNY  at  Stony  Brook. 

Continuous  administration  of  aerosolized  (J2  agonists  has  been 
suggested  as  an  effective  treatment  for  severe  reversible  airways 
disease  To  facilitate  continuous  therapy  and  avoid  a  feed  system  for 
SVNs,  the  Vortran  HEART  large  volume  medication  nebulizer  was 
developed  Manufacturer's  instructional  materials  provide  scenarios 
claimed  to  achieve  target  drug  delivery  rates  between  5  and  20  mg/hr  of 
albuterol  The  goal  of  this  study  was  to  validate  drug  delivery  rate  of  the 
HEART  nebulizer  in  the  laboratory  and  compare  it  against  conventional 
SVNs  Methods:  First,  "standing  cloud"  measurements  were  conducted 
on  a  series  of  HEART,  CIS-US  Aero-Tech  II  and  Hospitak  PowerMist 
nebulizers  so  as  to  select  samples  of  each  that  were  comparable.  Then 
output  studies  were  conducted  on  2  or  more  comparable  samples  of 
each  nebulizer  using  a  bench  model  consisting  of  an  adult  aerosol  mask 
on  an  anatomical  face  A  to-and-fro  adult  spontaneous  breathing  pattern 
(Vt  500  ml,  f  20,  Insp  Time  40%),  generated  by  a  sine  wave  ventilator, 
was  used  to  "inhale"  aerosol  through  the  mouth  of  the  anatomical  face 
Radiolabeled  Tc-albuterol/NS,  collected  on  absolute  filters  placed 
distal  to  the  mouth  of  the  face,  was  used  as  a  tracer  to  measure  Inhaled 
Mass  (the  %  of  the  mass  of  drug  or  tracer  placed  in  the  nebulizer  that 
was  actually  delivered  to  the  airway  opening)  Results:  For  3  HEARTS 
with  a  120  ml  fill  volume,  Inhaled  Mass  averaged  only  15  8%  after  240 
mm  of  operation  compared  to  34%  and  24  9%,  respectively,  for  2  Aero- 
Tech II  and  2  PowerMist  SVNs  with  3  ml  fill  volumes  that  all  ran  dry  at  8 
min  The  actual  drug  delivery  rate  of  the  HEART  in  the  5,  10,  15  and  20 
mg/hr  scenarios  is  only  0  79,  1  58,  2  36  and  3  16  mg/hr  respectively 
Conclusion:  The  HEART  nebulizer  did  not  deliver  the  target  dose 
specified  by  the  manufacturer  It  appears  that  gravimetric  techniques 
used  accurately  by  the  manufacturer  to  measure  the  HEART'S  liquid 
nebulization  rate  were  extrapolated  erroneously  to  predict  drug  delivery 
rates   Data  from  typical  SVNs  suggest  that  greater  drug  delivery  hourly 
rates  could  be  achieved  with  continuously  or  intermittently  filled  SVNs 
than  with  the  HEART  nebulizer  Nebulizer  output  performance  over  time 
is  best  expressed  by  Inhaled  Mass  % 

OF-95-195 


1182 


Respiratory  Care  •  November  'l)5  Vol. 40  Noll 


New 

Press-and- 
Release 
Action 

Simplified  design,  with 
fewer  moving  parts, 
makes  canister 
actuation  easier, 


In  NIDI  Drug  Delivery... 

The  choice  just  got  easier. 


Better  delivery. 


OptiHaler  is  designed  to  give  your  patients  the  full 
benefit  of  their  MDI  medication.  Its  patented  aerodynamic 
action*  creates  a  measurably  superior  aerosol  mixture  — 
richer  in  the  smaller,  more  effective  particles.1  And  it  makes 
more  of  that  mixture  available  for  delivery  to  the  lungs  than 
conventional  holding  chambers.1 


So  why  not  make  MDI  therapy  easier  for  your 
patients... with  the  product  more  patients  prefer.2  Call 
our  24-hour  customer  service  hotline  today  for  your  free 
professional  sample  of  new,  improved  OptiHaler. 


1-800-962-1266 

wmmsm 


Better  design. 


~T 


OptiHaler's  new  simplified  design  makes  MDI  therapy 
easier  than  ever.  Patients  simply  press  and  release  the 
canister  while  inhaling  —  then  close  the  end  cap  for  the 
next  puff.  Cleaning  and  maintenance  are  easier  too. 

Better  compliance. 

And  because  more  convenience 

usually  means  better  compliance, 

OptiHaler  packs  all  of  these 

advantages  into  a  sleek,  discreet, 

truly  portable  unit  that  patients  rate 

significantly  more  convenient  for 

daily  use  than  the  leading  holding  chambers 


/-> 


New,  more  convenient, 
one-piece  cap. 


Drug  Delivery  System  for  use  with  Metered  Dose  Inhalers 

The  promise  of  MDI  therapy... delivered. 

From  the  makers  of  ASSESS®  and  Personal  Best®  Peak  Flow  Meters 

HealthScan  Products  Inc..  Cedar  Grove,  NJ 

REFERENCES:  1 .  Data  on  file.  HealthScan  Products  Inc.  2  Wheeler  BB,  Boilers  ND  Initial  experi- 
ence with  a  novel  spacer  device.  (Presented  at  the  1993  meeting  ol  the  American  Academy  ot 
Allergy  and  Immunology)    '  U.S.  Patent  No  5,040,527     OA7600O4-0    ©1994.  HealthScan  Products  Inc 


Circle  118  on  reader  service  card 
Visit  AARC  Booth  1310  in  Orlando 


Monday,  December  4.  12:45-2:40  pm  (Rooms  230C-D) 


EFFECT  OK  INHALED  NITRIC  OXIDE  BEFORE,  DURING,  AND 
AFTER  CARDIOPULMONARY  RESUSCITATION 

Miller  Chris.  BA  RRT.  Dyer  David  BSc  RRT,  Elbarbary  Mahmoud,  MI). 

Caouette  Yvonne,  BA  RRT,  Hill  Wrae.  BSc  RRT,  Halees  Zohair,  MD 

King  Faisal  Specialist  Hospital  rt-  Research  Centre.  Riyadh,  Saudi  Arabia 

Case  Study 


An  8  monlh  old,  -1  kg.  male  inlam 
diagnosed  with  double  outflow  nyht 
ventricle  with  a  subpulmonary 
venlncular  septal  defect  presented 
postoperatively  with  pulmonary  artena 
pressures  IPAPJ  ranging  50  -70°  o  of 
systemic  anenal  pressures  (SAP) 
Moderate  oxygenation  was  achieved 
with  mechanical  ventilation  over  a  48 
iree  episodes  of  PAP  reaching  80-90%  SAP  with 
pressures  occurred  resulting  in  severe  anenal  oxygen 


hour  penod  Dunng  [hi 

suprasystemic  nght  ven 

desaturations  These  ensis  were  managed  successtulK  with  manual  hyperventilation  on 

100%  oxygen  On  the  third  day.  oxygenation  worsened  and  a  severe  suprasystemic  PAP 


episode  resulted  in  a  cardiac  anest  Despite  full 
open  hean  massage,  PAP  remained  50%  suprasys 
NO  therapy  was  initiated  dunng  cardiac  resuscita 
anest  a  dosage  of  30  ppm  NO  was  administered  \ 
PAP  immediately  reversed  with  a  dramatic  impro' 
hemodynamics  (Figure  2) 


attempts  with  medicamer 
c  wilh  severe  hypoxemia  (Figure 
Within  10  minutes  of  the  cardial 
modified  manual  bag  resuscitate 
:nt  in  oxygenation  and  stabilizati 


NITRIC  OXIRF  inoi  (Ml  NITROGEN  DIOXIDE (NOJ  LEVELS  Dl  RING  MANUAL 
VENTILATION.  Ray  Rnz  BA  RRT.  Dean  Hess  PhD.  RRT.  C  Alvin  Head  MD.  Roben 
Kacmarek  PhD.  RRT    Respiratory  Care  and  Anesthesia.  Massachusetts  General  Hospital  and 
Harvard  Medical  School,  Boston.  MA 

Mechanically  ventilated  patients  who  are  administered  inhaled  NO  to  support  oxygenation  or 
reduce  pulmonary  artery  pressure  may  require  surgical  or  diagnostic  procedures  not  available  al 
the  bedside    This  requires  manual  ventilation  during  transport    Tolerance  of  the  discontinuatioi 
of  NO  and  manual  ventilation  with  an  FIO;  of  1  0  varies  between  patients.  We  evaluated  the 
clinical  feasibility  of  maintaining  NO  and  NO,  levels  with  laboratory  conditions  of  simulated 
manual  ventilation    METHODS:   A  disposable  adult  manual  resuscitator  (Intenec.  Fort  Myers 
FL)  was  attached  to  a  mechanical  lung  model  and  a  respirumeter    A  gas  sample  port  and  an  O, 
analyzer  were  placed  in  sequence  between  the  resuscilalor  and  Ihe  lung    A  pneumatically 
powered  valve  directed  all  gas  delivered  from  Ihe  lung  into  the  room,  thus  avoiding  inadvertent 
measurement  of  NO.  formed  in  the  lung    A  Y-connection  was  inserted  into  the  resuscitalor's  0: 
supply  tube  I  8  in  from  the  bag  and  NO  180°  ppm)  was  added  from  a  0  -  I  L  (low  meter  I 
desired  source  NO  level  was  obtained  (condition  A  -  10  ppm.  condition  B  -  20  ppm.  and 
condition  C  -  40  ppm)  The  source  NO/NO,  level  was  confirmed  using 
NOW,  analyzer  (Eco  Physics  Model  CDL  700AL).  Source  gas  flow  was  varied  al  10  and  I  5 
Umin    Tidal  volumes  of  0  5  and  10  L  were  delivered  at  rates  of  10  and  20'min.  NO,  was  alsc 
measured  in  the  resuscitator  after  5  min  of  non-use  following  the  10/min  -  0  5  L  run    Each 
condition  was  repeated  3  times  and  the  mean  reported    RESULTS:   Data  obtained  from  sourci 
gas  flow  of  15  L/min  appears  in  the  table  below    Data  with  source  gas  set  at  10  L  mm  differed 
only  in  that  the  delivered  NO  varied  more  from  the  source  NO  as  the  minute  ventilation 
increased    The  delivered  FIO;  maintained  a  similar  relationship  with  the  source  FIO:  as  did  the 
NO  in  both  source  flow  conditions    Ambient  NO  and  NO;  levels  prior  to  lesting  were  m 
at  0  025  and  0,022  ppm.  respectively    Immediately  after  the  highest  flow  ( 1 5  L/min)  of 
ppm  NO,  ambient  NO  and  NO,  levels  were  0  057  and  0  057  ppm,  respecli 


the 


NO 
Condition 

NO  Level 

V,0  5L 
rate  1(1  mm 

VT0  5  L 
rate  20  mm 

V,  1  0L 
rate  10/min 

V,  1  0  1. 
rate  20/min 

non-use 

NO  Levels 

A 

10  7  ppm 

10,3 

99 

99 

6.5 

H 

20  0  ppm 

189 

179 

183 

146 

i 

39  5  ppm 

38  1 

372 

37  2 

>  8 

NO,  Levels 

A 

0  1  ppm 

0.3 

0  1 

02 

0  1 

0  6 

B 

0  4  ppm 

05 

02 

0  1 

0  1 

12 

c 

1  6  ppm 

2  1 

1  7 

!  S 

06 

-'5 

CONCLUSION:  Delivered  NO  concentrations  can  vary  from  Ihe  source  NO  as  minute 
ventilation  increases    Higher  source  gas  flows  may  help  maintain  the  desired  inspired  NO  level 
When  delivering  20  ppm  NO  or  less,  NO,  concentrations  may  fall  within  an  acceptable  range, 
but  periods  of  non-use  can  result  in  temporary  but  significant  increases  of  NO,  in  the 
resuscitator    Scavenging  NO  and  N02  during  transport  is  difficult  and  may  not  be  n 


LAB  EVALUATION  OF  NITRIC  OXIDE  DELIVERY  VIA  TRANSPORT  VENTILATOR 
■Inhn  Newhart  RCP  CRTT.  F.  Wayne  Johnson  RCP.  Richard  N  Channick  MD 
UCSD  Medical  Center,  San  Diego,  Ca   The  ability  ol  inhaled  nitric  oxide  (INO)  to 
improve  pulmonary  hypertension  and  hypoxia  has  been  previously  described  in 
Ihe  literature    Al  our  institution  INO  has  been  utilized  in  selected  patients  with 
ARDS  and  pulmonary  hypertension   Because  some  of  these  patients  need  to  be 
transported  to  ancillary  services,  we  devised  a  simple  method  of  delivering  INO 
via  our  transport  ventilator    We  evaluated  the  performance  of  this  system  in  a 
laboratory  setting  Background   Our  transport  systems  are  based  on  the  Puritan 
Bennett  Companion  2800  (2800)  ventilator  (Puritan  Bennett.  Lenexa  Kansas) 
mounted  on  a  specialy  built  cart  to  transport  patients  throughout  the  institution 
(Cates.  Resp  Prac.  88)   The  2800  is  a  piston  type  home  care/transport 
venlilator  that  has  pediatric  and  adult  capabilities.  Oxygen  enrichment  is 
achieved  by  means  of  an  internally  battled  02  accumulator  attached  to  the  gas 
intake.  Methods  We  used  nitric  oxide  (NO)  450ppm  balance  nitrogen   as  source 
gas  The  NO  cylinder  was  inserted  into  a  fabricated  holder  that  was  attached  to  the 
transport  cart    Attached  lo  Ihe  NO  cylinder  is  a  stainless  sleel  regulator  (Puritan 
Bennett)  and  a  0-3  Ipm  How  meter   The  NO  was  titrated  via  How  meter  into  the 
ventilator  oxygen  accumulator  through  a  "Y"  lilting   Pure  oxygen  from  an  "E" 
cylinder  was  introduced  into  the  accumulator  via  the  other  branch  of  the  "Y"  A 
0-15  Ipm  How  meler  was  used  for  02  titralion    Expired  NO  and  Nitrogen  Dioxide 
N02  was  scrubbed  by  passing  Ihe  exhalate  Ihrough  a  4"x  20"  acrylic  cylinder 
filled  with  potassium  permanganate  pellets   This  cylinder  was  attached  to  the 
transport  cart    Analysis  ol  inspired  NO  and  (N02)  was  via  a  API  200 
Chemiluminescent  analyzer  (Advanced  Pollution  Instrumentation  San  Diego  CA.) 
with  Ihe  sample  line  al  Ihe  ventilator  outlet   Oxygen  was  analyzed  with  a  MiniOx  I 
(MSA  Medical  Products  Piltsburg,  PA)  at  the  outlet  port  ol  Ihe  ventilator  The 
ventilator  was  attached  to  a  Bio-Tek  VT1  lung  simulator  (Bio-Tek  Instruments 
Inc.  Winooski  VT)    Ventilator  sellings  were  (VI  IL,  RR  15,  Flow  60  LPM.  PIP 
22  cmH20.  PEEP  0,  Mode  Control)  Results   By  manipulating  Ihe  NO  and  02 
flowmeters  the  lollowing  concentrations  were  delivered  from  the  venlilator 
All  values  are  flow  rates  expressed  in  LPM  NO.  (02) 
60%  02  80%  02  95%  02 

0  375  (7,5)  0  375  (12)  0   5  (23) 

0  875  (10)  0  875  (13)  1,5  (22) 

2  0(10)  2.125(13)  not  possible 

Conclusion  The  highest  inspiratory  N02  concentration  measured  was  0  3PPM 
This  is  below  Ihe  5ppm  OSHA  Standard  Exhaled  gas  from  Ihe  scrubber  was  NO 
0PPM,  N02  0PPM    INO  can  be  salely  delivered  and  Ihe  exhalate  scavenged  while 
utilizing  Ihe  Bennett  2800  venlilalor.  enabling  transport  of  palienls  without 
mlerruption  ol  INO 

OF-95-171 


NO  Delivered 
NO  10PPM 
NO  20PPM 

NO  40PPM 


ENVIRONMENTAL  EXPOSURE  OF  NITRIC  OXIDEV  NITROGEN  DIOXIDE  I 
■Mini  nilRlNrt  RIMIIIATFD  MFCHANICAL  VENTILATION    Kelvin  MacDona 
R.C.P..C  R  T  T.  John  Cefaratt.  B  S   R.R  T     Kaiser  Permanente,  Los  Ange 

INTRODUCTION   Inhaled  Nitric  Oxide  (NO)  appears  to  be  an  effective  tool  in 
treatment  of  Persistent  Pulmonary  Hypertension  (PPHN)  and  as  an  alternate 
ECMO  However,  there  are  concerns  about  secondary  exposure  to  hearth  car 
Some  investigators,  including  ourselves  use  "scavenging*  on  the  expiratory  I 
reduce  nsk.  others  report  they  do  not  We  sought  to  measure  the  ambient  le 
nitric  oxide  (NO)  and  nitrogen  dioxide  (N02)  in  model  of  administration  in  an 
METHODS   In  an  vacant  NICU  (2500  sq   ft),  we  assembled  an  Infrasonic  (Sa 
CA)  Infant  Star  Classic  ventilator,  80  cm  long  standard  infant  circuit  with  hea 
Fisher  &  Paykel  (New  Zealand)  MR  360  humidifier,  and  custom  drop  line  to  al 
entramment  and  sampling  of  NO/N02  This  was  connected  to  a  static  test  lu 
compliance  of  1  ml/cm  H20,  resistance  20  cm  H20/Usec     A  Pulmonox  II  (1 
Canada)  electrochemical  NO/N02  analyzer  was  setup  and  calibrated  accordi 
manufacturers  specification   Measurements  of  NO  and  N02  levels  in  the  arc 
recorded  at  the  drop  line   Effluent  gases  were  sampled  through  a  special  NO 
sampling  block  connected  to  wall  suction  set  at  a  rate  sufficient  to  draw    12  I 
measured  by  a  Boehnnger  respirometer,  10  cm,  from  the  exhalation  port 
Measurements  were  taken  at  10  parts  per  million  (PPM)  step  intervals  from  1( 
100  PPM  introduced  and  measured  at  the  patient  circuit  Each  step  interval  Vt 
recorded  on  both  IMV  (IMV  25,  2S/3  45  1  time,  1  0  Fi02)  and  HFV  (MAP  10 
time    1  0  Fi02   30  amplitude  and  10  Hz)  5  minutes  were  allowed  for  stabilize 
each  readma  RESULTS   Shown  in  the  table 

J  AN 

the 
e  to 

*JICU 
n  Diego. 

g  with 

oefield, 

gto 

lift  were 

N02 

m. 

PPM  to 

45  1 

HsetNOPPM 

NO  on IMV 

NO  on  HFV 

N02  on  IMV 

N02onHFV 

10 

0 

0 

0 

o 

2) 

0 

0 

0 

0 

30 

0.5* 

0 

or 

9D 

1 

0 

0 

o 

s 

1 

0 

0 

o 

70 

IS" 

60 

1  7" 

05' 

0 

0 

90 

r 

T 

0 

o 

25' 

15' 

On  IMV  a 

at  exhaus 

undetecta 
difficult  w 

covering 
Addltloni 

standard 

nd  HFV  internally,  read  NO  increased  as  set.  from  10  PPM  -  100  P 
rients  increased  from  0  PPM  to  0  8  PPM  at  100  PPM  NO  On  meas 
t  NO  increased  from  0  PPM  to  2  5  PPM  dunng  IMV  (r=0  99).  while 
ble   On  HFV.  NO  measured  from  0  PPM  up  to  1  5  PPM  <r=0  79)  wt 
ble    DISCUSSION:  Setting  up  a  scavenging  system  that  is  function 
th  some  infant  ventilators   In  our  experience,  this  has  required  mine 
on  to  exhalation  assemblies  and/or  circuits   Often,  e  canopy  or  oth 
aver  the  assembly  is  required,  reducing  visibility  of  the  verve  and  it 

y   applying  a  vacuum  to  the  exhalation  could  inadvertently  produce 
effect   CONCLUSION:  Our  data  suggest  the  exposure  levels  of  NO 
an  previously  thought  and  below  the  20  PPM  over  8  hours  suggeste 
Scavenging  exhaled  gas.  while  somewhat  simple  may  not  be  requir 

ventilated  room                 *  ivvragad  valua 

>M    N02 

J02  was 
hN02 
al  can  be 

function 

N02  may 
d 

DF-95-218 

11X4 


RESPIRATORY  CARP.  •  NOVPMBPR  "95  VOL  40  NO  1 1 


Monday.  December  4.  12:45-2:40  pm  (Rooms  230C-D) 


NITRIC  OXIDE  AND  THE  MEASUREMENT  OF 
METABOLICS  WITH  A  PURITAN-BENNETT  7250 
METABOLIC  MONITOR 

F  Wavne  Johnson  RCP  CRTT  RPFT  RCPT.  K  Knaus  Kinninger  RCP  RPFT 
Kathy  Jacobson  RDA,  John  Ncwhart  RCP  CRTT.  David  Bums  MD, 
UC-San  Diego  Medical  Center.  San  Diego  California 

Introduction:  In  the  mechanically  ventilated  critically  ill  patients,  the  use  of 
indirect  calonmetry  for  assessing  energy  expenditure,  measure  of  substrate 
utilization  (Stephen,  NCP,  92;  7:207)  and  independent  V02  measurements  for 
02  uptake  and  02  demand  have  been  suggested  (Ronco,  ARRD,  91:143:1267). 
Recent  reports  of  Inhaled  Nitric  Oxide  (INO)  as  a  potent  dilator  of  vascular 
smooth  muscle  have  demonstrated  its  usefulness  in  managing  critically  ill 
patients  (Rossaint,  N  Engl  J  Med,1993;  328:399).  In  the  laboratory  simulations 
during  mechanical  ventilauon.  we  examined  whether  delivered  INO  and  FI02 
influence  the  accuracy  of  the  measurement  of  V02/VC02  with  a  open  circuit 
metabolic  monitor  (PB7250.  Puritan-Bennett.  Carlsbad  CA).  Methods:  The 
simulation  of  V02  /VC02  was  achieved  by  the  N2/C02  infusion  technique  with 
a  constructed  lung  model  (Damask.  Anesth.,  1982.  57:213.).  Delivery  of  INO 
utlized  the  technique  where  NO  and  N2  were  blended  with  additional  N2 
(Channick.  Chest  94;  105: 1842).  Using  a  prototype  stainless  steel  blender  (Bird 
Corp..  Palm  Springs.  CA).  A  chemiluminescence  analyzer  (  API  Inc.,  San 
Diego,  CA)  was  used  to  continuously  measure  the  delivered  NO  and  N02. 
Exhaled  gas  was  scavenged  from  the  exhalation  port.  A  PB7200ae  ventilator  and 
7250  Metabolic  Monitor  accessory  were  utilized  in  a  CMV  mode  of  ventilation; 
ramp  waveform;  peak  flow  of  60  Umin,  Vt  .700  L;  f  1 8;  PEEP  0  cm  H20;  I/E 
ratio  1:1.6  andFI02of  21.  .40.  .60,  .80.  At  each  level  of  FI02  for  comparison 
purposes  V02  /VC02  simulations  at  .300  Lmtin  were  made  with  INO  of  20ppm 
and  without  INO.  Results:  The  comparison  of  V02/VC02  measurements  with 
and  without  delivered  INO  are  presented  in  the  table.  Across  all  measurement 
levels  the  mean  difference  between  methods  (Bias)  and  the  standard  deviation  of 
the  difference  (Precision)  were  determined  to  show  agreement  between  data  sets 
(Bland,  Lancet.  1986;  Feb:307-310). 

V02       VC02 
BIAS  %  0.60  0.75 

PRECISION  1.20  0.93 

Conclusions:  Over  a  wide  range  of  FI02  levels,  V02/VC02  values  obtained 
using  the  PB7250  Metabolic  Monitor  were  comaparable  and  within  accetable 
limits  to  measurements  with  and  without  LNO  delivery.  Our  data  suggests  INO 
of  <  20  ppm  has  no  affect  on  the  performance  of  open  circuit  metabolic 
monitors. 


INHALED  NITRIC  OXIDE  IMPROVES  OXYGENATION  BUT  WORSENS 
LUNG  MECHANICS  IN  EXPERIMENTAL  RESPIRATORY  DISTRESS 
SYNDROME. 

David  Ganon  CRTT. RCP.  Randy  Scott  BS.RRT.RCP.  Leo  Langga  BS.RRT.RCP, 
Ricardo  Peverini  MD,  Andrew  Hopper  MD  Loma  Linda  Children's  Hospital.  Loma 
Linda,  Ca. 

In  premature  infants,  pulmonary  hypertension  concomitant  with  severe  Respiratory 
Distress  Syndrome  (RDS)  increases  morbidity  and  mortality,  despite  exogenous 
surfactant.  Studies  have  shown  that  inhaled  nitnc  oxide  (INO)  improves  pulmonary 
hemodynamics  and  gas  exchange  in  experimental  RDS.  yet  little  is  known  about  the 
effect  of  INO  on  lung  mechanics.  To  study  the  effects  of  INO  on  lung  mechanics,  we 
cannulated  the  trachea,  jugular  vein  and  carotid  artery  of  6  sets  of  126-130  day 
gestational  (0.85  term)  lamb  twins  A  modified  natural  surfactant  (beractant)  was  given 
pnorto  delivery  and  initiation  of  mechanical  ventilation  (Sechnst  IV  100B).  Initial 
ventilator  settings  were  rate  40  bpm,  PIP  set  to  deliver  a  tidal  volume  (VT)  of  8  ml/kg, 
PEEP  4  cmH20,  inspiratory  time  0  5  seconds,  and  FIOj  1.0.  FIO;  and  PIP  were 
adjusted  to  maintain  PaO:  50-80  ton  and  PaCO:  35-45  torr.  After  2  hours  of 
mechanical  ventilation,  baseline  lung  mechanics  and  arterial  blood  gases  (ABGs)  were 
recorded  Lambs  were  randomly  assigned  to  receive  either  20  ppm  INO  or  no  INO 
(control)  for  30  minutes  INO  and  control  assignments  were  then  switched  and  another 
30  minute  trial  completed.  Lung  mechanics  and  ABGs  were  recorded  at  the  end  of 
each  trial.  Variables  calculated  from  recorded  data  were,  PaO?  /  FIO2,  VT,  dynamic 
compliance  (CDyn).  airway  resistance  (Raw  ),  and  functional  residual  capacity  (FRC). 
For  statistical  analysis,  normally  distributed  data  were  compared  by  paired  t  test. 
Differences  were  considered  statistically  significant  when  p  s  0.05.  Data  in  the  table 
are  an  increase  (+)  or  decrease  (-)  mean  ±  SE  of  %  change  from  baseline  during  the 


study  period 

PaO./FlO- 

Vt 

C„y« 

Raw 

FRC 

INO 
CONTROL 

+45  ±  28% 
-15  ±9% 

0  07 

-15  ±6% 

+  13  ±6% 

002 

-12  ±6% 

+  10  ±6% 

0  06 

00 

+6  ±  9% 

0  50 

-1  ±  9% 

+4  ±  10% 

0.66 

Oxygenation  (PaO;  /  FIOr)  improved  dunng  INO  despite  deterioration  of  VT  and  CDyn 
The  improvement  in  oxygenation  is  consistent  with  previously  reported  studies.  We 
conclude  that  while  INO  may  improve  oxygenation,  it  may  also  worsen  lung 
mechanics.  This  worsening  of  lung  mechanics  could  increase  the  risk  of  barotrauma 
and  adversely  affect  long  term  outcome. 


METHEMOGLOBIN  PRODUCTION  RATES  AT  THREE  LEVELS  OF 
HEMOGLOBIN  SATURATION  AND  80  PPM  NITRJC  OXIDE 

Daniel  Fisher,  Robert  M.  Kacmarek,  Warren  M.  Zapol,  C.  AJvin  Head 
Department  of  Anesthesiology  and  Respiratory  Care,  Massachusetts 
General  Hospital  and  Harvard  Medical  School,  Boston,  MA 

Inhaled  nitric  oxide  (NO)  can  improve  oxygenation  and  lower  pulmonary  artery 
pressure  in  humans  without  systemic  vascular  effects.   The  selectivity  of  inhaled  NO 
for  the  lung  is  due  to  its  great  affinity  for  the  iron  moiety  of  hemoglobin  (Hb). 
However  upon  binding,  the  iron  is  oxidized  producing  methemoglobin  (Mhb)  and  this 
reduces  the  oxygen  carrying  capacity  of  Hb,   This  study  was  conducted  to  determine 
the  relationship  between  oxyhemoglobin  saturation  (SaOJ,  nitric  oxide  and  the 
production  of  Mhb.   METHODS:   Fifteen  ml  of  blood  was  heparinized  and 
immediately  divided  into  three  tubes  for  tonometry  (RNA  medical)  from  each  of  five 
healthy  volunteers.   The  blood  was  lonometered  with  different  gas  concentrations  of 
nitrogen,  oxygen  or  both,  to  produce  three  different  SaO:  levels  of    0,  75  and  100%. 
While  maintaining  the  same  delivered  FiO;,  80  ppm  NO  was  added.   The  %  Mhb  of 
the  total  Hb  in  each  sample  was  measured  (Ciba-Corning  270  CO-oximeter)  before  NO 
and  every  10  minutes  for  140  minutes  during  NO  exposure.   RESULTS:  %Mhb 
increased  in  all  samples  with  100  >  75  >  0%  SaO,  (p  <  0.05).   Mean  +  /-  SD  for 
samples  at  each  Sa02  is  presented  below: 


Time 
(mins) 

%Mhb  with 
0%  SaO; 

%Mhb  with 
75%  SaO, 

%Mhb  with 
100%  SaO, 

0 

0.12  +/-0.1S 

0.13  +/-0.10 

0  30  +/-0.00 

20 

0.25  +/-0.15 

1.90  +/-1.31 

2.60+/-  0.93 

40 

0.42  +  /-0.26 

3.73  +/-  1.90 

7.28  +/-2.63 

60 

0.68  +/-0.20 

5.67  +/-  1.69 

16.88  +/-  11.73 

80 

1.00  +/-0.48 

7.60  +/-  1.81 

25.82  +/-  19.91 

100 

1.40  +/-0.84 

9.78  +  /-2.80 

27.98  +/- 31.18 

120 

1.70  +/-  1.02 

12.03  +/-4.73 

44.38  +/- 30.55 

140 

2.35  +/-  1.32 

14.88  +/-7.31 

47.73  +/- 27.64 

CONCLUSIONS:  (1)  Using  whole  blood  from  healthy  humans,  80  ppm  NO 
%Mhb  both  as  a  function  of  time  and  SaOj,  in  vitro.  (2)  The  clinical  signific; 
these  findings,  in  vivo,  have  not  been  established. 


INSPIRED  VERSUS  TRACHEAL  [NO|.  Dean  Hess.  PhD.  RRT.  Robert  M  Kacmarek, 
PhD,  RRT,  William  E  Hurford.  MD    Departments  of  Respirator)  Care  and  Anesthesia, 
Massachusetts  General  Hospital  and  Harvard  Medical  School,  Boston  MA, 
Several  sites  have  been  reported  for  analysis  of  [NO]  in  therapeutic  delivery  systems. 
Although  [NO]  is  most  commonK  measured  in  the  inspiratory  limb  of  the  ventilator,  others 
have  measured  [NO]  tn  the  trachea    We  have  found  that  exhaled  [NO]  is  25  -  75°-o  of  inhaled 
[NO]  in  patients  with  ARDS    We  designed  a  lung  model  study  to  determine  whether  tracheal 
[NO]  is  less  than  inspired  [NO],  and  if  it  is  affected  by  IE  ratio  and  expired  [NO], 
METHOD:  A  Puritan -Bennett  7200  ventilator  was  set  to  deliver  a  tidal  volume  of  0.75  L, 
rate  12  breaths/min,  FlO,  0  60,  and  IE  ratio  of  1:3.  1:2,  II.  or  2:1.  Nitric  oxide  (785  ppm  in 
N,)  was  diluted  with  N:  (Bird  Air'O,  Blender,  Palm  Springs  CA)  and  added  to  the  high 
pressure  air  inlet  of  the  ventilator  to  produce  an  inspired  [NO]  of  20  ppm    A  dual-chambered 
test  lung  (Michigan  Instruments.  Grand  Rapids,  MI)  was  configured  so  that  the  exhaled  gas 
was  precisely  controlled  to  0  ppm  NO  (N,).  7  ppm  NO  in  N..  or  14  ppm  NO  in  N2.  The  test 
lung  configuration  was  similar  to  that  previously  used  to  separated  measure  inspired  and 
expired  gases  during  calorimeter  validation.1  NO  was  measured  by  chemiluminescence  (Eco 
Physics  CLD  700AL,  calibrated  with  80  ppm  NO  and  used  with  the  slow  digital  filter),  Gas 
was  alternately  sampled  from  the  inspiratory  ventilator  circuit,  expiratory  ventilator  circuit, 
and  from  a  14  gauge  catheter  (Becton-Dickinson,  Sandy.  UT)  placed  into  the  model  trachea 
Because  the  [NO]  measured  in  the  trachea  fluctuated  during  the  respiratory  cycle,  tracheal 
[NO]  was  recorded  as  the  average  of  the  highest  and  the  lowest  values.  The  sample  rate  of  the 
analyzer  was  660  mL'min.  RESULTS:  The  tracheal  [NO]  was  less  than  the  inspired  [NO] 
(20  ppm)  for  all  measurements    The  difference  between  inspired  [NO]  and  tracheal  [NO] 
became  less  at  longer  inspiratory  times  and  higher  expired  [NO]    There  was  a  significant 
difference  between  tracheal 
[NO]  for  the  IE  ratios  (P  = 

0  008)  and  expiratory  [NO] 
concentrations  (P<  0.00 1). 
As  shown  in  the  Figure,  the 
tracheal  [NO]  may  be 
considerably  less  than  the 
inspired  (NO]  of  20  ppm. 
Unlike  tracheal  [NO],  [NO] 
in  the  inspiratory  limb  of  the 

affected  by  changes  in 

expiratory  [NO]  or 

ventilatory  pattern 

CONCLUSIONS:  To  compare  the  results  of  studies  of  inhaled  [NO],  it  is  important  that  the 

inhaled  [NO]  is  measured  in  a  similar  manner    We  urge  investigators  to  monitor  and  report 

inhaled  [NO]  from  the  inspiratory  limb  of  the  ventilator  circuit,  because  this  is  the  only  true 

measure  of  the  inhaled  dose    (supported  in  part  by  the  Purit. 

1  RitzR,  Cunningham  J.   Indir 
Monitoring  in  respiratory  car 


t  Corporation) 
:alorimetry.  In:  Kacmarek  RM,  Hess  D.  Stoller  JM 
Mosby  •  Year  Book,  Chicago,  1993 


Respiratory  Care  •  November  '95  Vol  40  No  11 


1185 


Monday.  December  4.  12:45-2:40  pm  (Rooms  230C-D) 


AIR  TRANSPORT  OF  A  VENTILATED  INFANT REQ1  DUNG  NITRIC  OXIDE 

THKRAn  •  (ASK  Ml  l>Y  Michcal  Frcnt/cl.  RRT.  MHA.  T.  Pearson- Shaver,  MD.  Departmen 
of  Pediatrics.  Medical  College  of  Georgia,  Augusta,  Ga. 

We  report  a  case  srud>  in  which  the  successful  air  transport  of  a  patient  receiving  nitric  oxide 
plaved  .1  Ice)  role  in  the  patient's  outcome  As  experimental  use  of  nitric  oxide  ("NO)  gas  as  an 
inhaled  pulmonan  vasodilator  becomes  more  widespread  the  potential  for  transport  of  patients 
requiring  NO  could  become  more  frequent  This  patient  had  an  initial  diagnosis  of  coarctation  of 
the  Aorta  which  was  repaired  at  approximately  two  weeks  of  age  At  26  days  post  surgical  repair 
the  patient  suit  remained  ventilator  dependent  requiring  hyperventilation  and  inotropic  therapy  for 
the  treatment  of  pulmonary  hypertension  At  this  time  NO  was  initiated  and  improvement  in  Pa02 
was  seen.  For  the  next  seven  weeks  the  patient  received  NO  50  to  80  ppm  via  the  Servo  900C 
ventilator  NO  and  blended  gas  were  titrated  into  the  low  flow  port  of  a  Servo  WOC  ventilator 
NO-NO;  levels  were  monitored  on  the  inspiratory  limb  of  the  circuit  using  a  Bedfont  NO/NO. 
EC90  monitor  Attempts  to  wean  the  patient  from  NO  failed.  A  diagnosis  of  Pulmonary  Vascular 
Obstructive  Disease  was  confirmed  The  determination  was  made  that  a  lung  transplant  was  the 
patient's  only  option  for  long  term  survival  Since  our  institution  did  not  ofler  this  service  we  wouli 
have  to  air  transport  the  patient  to  a  facility  which  did  The  patient  would  require  NO  therapy 
during  the  transport  to  maintain  oxveeiutmn   Several  problems  involv  ing  the  transport  became 
ev  idem  The  equipment  itself  was  cumbersome,  NO/NO;  exhaust  from  the  ventilator  and 
resuscitation  bag  required  a  scavenging  svstem.  careful  titration  and  monitoring  of  inhaled  NO  gas 
would  be  needed  during  transport  The  patient  monitors,  NO/NO:  monitors  and  Servo  ventilator 
were  mounted  on  an  adult  stretcher  with  the  patient  We  also  took  a  topaz  battery,  cylinders  of 
oxygen,  air  and  NO  for  the  mechanical  ventilator  during  the  transport  In  the  event  that  the 
ventilator  malfunctioned  we  modified  an  Ambu  resuscitation  bag  equipped  with  a  closed  reservoir 
and  one-way  valve  proximal  to  the  bag  itself  Delivered  NO/NO.  levels  were  measured  in  the 
modified  resuscitation  bag  The  exhaust  from  the  resuscitation  bag  was  scavenged  via  a  suction 
system  to  prevent  exposure  of  NO  "NO;  to  personnel  A  medically  equipped  Hawker  jet  was  used 
for  the  transport  The  jet's  suction  svstem  emptied  outside  of  the  patient  cabin  so  personnel  were 
not  exposed  to  the  scavenged  NO  "NO.  from  the  ventilator  or  resuscitation  bag  The  jet  cabin  and 
ambulance  were  monitored  for  the  presence  of  NO  NO,  during  transport,  levels  were  well  within 
OSHA  standards  The  transport  was  successful  but  not  without  difficulty  Saturations  per  oximetry 
remained  greater  than  90°o  throughout  the  transport   Moving  all  the  equipment  as  a  unit  required 
coordinated  effort.  The  ventilator  battery  did  not  last  the  entire  trip  and  manual  ventilation  was 
necessary  for  the  last  1 5  minutes  of  the  transport  Delivered  NO  level  was  monitored  at  50  to  60 
ppm  during  mechanical  ventilation  and  manual  resuscitation  A  lung  transplant  was  done  within  a 
TtMk  d,i\  s  ol  the  patients  transport  to  the  facility  Six  weeks  after  the  transplant  the  patient  was 
completely  weaned  from  mechanical  ventilation,  and  then  discharged  from  the  hospital  several 
weeks  later.  We  believe  a  safe  transport  to  the  facility  was  key  for  this  patient's  outcome,  but  not 
without  some  obstacles  In  the  future  a  smaller  batten,  powered  ventilator  that  could  deliver  NO 
would  be  more  ideal  It  would  also  have  been  helpful  to  have  had  some  kind  of  built  in  scavenging 
system  Transport  vehicles  should  be  equipped  with  an  electrical  source,  suction  source  and  50 
p.s  i  gas  source    We  believe  that  with  improvements  transporting  patients  requiring  NO  could  be 
made  safer  and  easier  in  the  future 


RESPONSE  OF  CHEMILUMINESCENT  ANALYZERS  ON  THE  MEASURED 
VALUE  OF  NITRIC  OXIDE  (NO) 

MasaiiNishimura.MD.  Chikara  Tashiro,  MD,  Yuji  Fujino.  MD,  Hideaki  Imanaka, 
MD.  Dean  Hess,  RRT,  PhD,  Robert  M  Kacmarek,  RRT,  PhD.  Hyogo  College  of 
Medicine,  Hyogo,  Japan.  Massachusetts  General  Hospital,  Boston,  MA 


It  has  become  increasingly  common  to  use  inhaled  nitric  oxide  (NO)  for  patii 
acute  lung  injury.  The  gold  standard  for  NO  measurements  is  chem 
However,  its  response  is  very  slow  because  it  is  designed  to  neglect  noise  during 
investigation  of  air  pollution  This  slow  response  of  the  analyzer  causes  problems 
when  it  is  used  for  a  clinical  setting.  In  this  study,  we  investigated  the  response  time 
of  two  NO  chemiluminesccnt  analyzers,  and  compared  the  measured  values  of  each 
analyzer  when  NO  concentration  fluctuated. 

Methods:  Two  chemiluminescent  analyzers  (Model  270B  NOA.  Sievers  Instruments, 
Inc.  Boulder,  CO,  and  CLA  510S.  Horiba,  Kyoto,  Japan)  were  employed.  The 
transport  delay  and  dynamic  response  time  were  measured  by  a  balloon  puncture  in  a 
glass  chamber  fNoguchi  et  al,  J  Appl  Physiol  52  79-84. 1 982).  Then  fluctuation  of  NO 
concentrations  was  created  by  delivering  100  mL/min  of  NO  gas  (92  ppm  in 
nitrogen)  into  4  L/min  of  nitrogen  gas  stream  NO  concentration  inside  a  ventilator 
circuit  was  also  measured  at  20  inch  both  upstream  and  downstream  of  the  airway 
opening  and  at  "Y"  between  a  patient  and  the  circuit. 

Results:  90%  response  time  of  each  analyzer  was  0.20±0.02  sec  for  270B  NOA,  and 
8.42±1 .13  sec  for  CLA  5 I0S.  When  NO  concentration  fluctuated  between  0  and  2.3 
ppm,  270B  NOA  gave  a  correct  value  of  0  and  2.3  ppm,  while  CLA  510S  gave  a 
value  between  0.93  and  1.15  ppm.  When  NO  was  measured  at  the  airway  opening  of 
a  patient,  270B  NOA  and  CLA  5 1  OS  exhibited  84.0%  and  45.3%  of  NO 
concentration  measured  at  inspiratory  limb,  respectively.  The  analyzer  with  a  long 
response  time  gave  us  a  value  of  mean  inhaled  and  exhaled  NO  concentration  and 
therefore  it  was  not  a  real  value  of  inhaled  NO.  Figure  shows  NO  concentration 

measured  at  the  airway  opening. 
Conclusion:  NO  analyzers 
showed  significant  difference  in 


ppm 


,  270B  NOA 


CLA  510S 


re -pon 


When  NO  was 
lyzed  at  the  airway  opening, 
value  was  less  than  half  of 
true  value  with  a  long 
lonse  time  analyzer   Inhaled 


NO  should  be  measured  e 
inspiratory  limb 


the 


EVALUATION  OF  ELECTROCHEMC1AL  NITRIC  OXIDE  ANALYZERS.  Edward  P 

Punz.  BS.  RRT.  Dean  Hess  PhD,  RRT.  Robert  M  Kacmarek.  PhD.  RRT    Respiratory  Care  and 
Anesthesia,  Massachusetts  General  Hospital  and  Harvard  Medical  School,  Boston,  MA 
Although  it  remains  investigational,  inhaled  nitric  oxide  ("NO)  is  being  used  increasingly  in  the 
treatment  of  PPFTN.  ARDS,  and  pulmonary  hypertension    It  is  used  clinically  in  doses  <  80  ppm 
and  often  at  doses  <  20  ppm    NO  is  usually  mixed  with  O,  and  delivered  through  a  ventilator  to 
the  patient.   The  purpose  of  this  study  was  to  evaluate  the  accuracy  of  electrochemical  NO 
analyzers  that  have  recently  become  available    Methods:   We  evaluated  the  following  NO 
analyzers   Pulmonov  II  (Pulmonox.  Alberta,  f  .madat   NUxBOX  (Bedfont.  Kent,  England),  and 
the  Saan  (Taiyo  Sanso,  Osaka,  Japan)    Thcv  were  provided  by  their  manufacturers,  calibrated  as 
recommended  and  used  per  manufacturer's  specifications    A  Puritan -Bennett  7200  ventilator 
was  used  to  produce  serial  dilutions  of  NO  with  O,  to  deliver  [NO]  of  0-  80  ppm  (RespirCare 
1994,39  1113)    HO.  settings  of  0  90.  0.70.  0,50,  0.30,  and  0.2 1  were  used  to  produce  serial 
dilutions  of  NO    The  high  pressure  0:  inlet  of  the  ventilator  was  attached  to  50  psi  0:  and  the 
high  pressure  air  inlet  was  attached  to  NO  (80,  40,  or  20  ppm  in  N.).  The  following  ventilator 
settings  were  used  flow-by  10  L'min,  CPAP  5  cm  H.O;  PEEP  5  cm  HX>,  PC  10  cm  H:0;  PEEP 
7,5  cm  H.O.  PC  IScmHjO,  PEEP  10  cm  H,0,  PC  20  cm  H,0.  PEEP  12.5  cm  H:0,  PC  25  cm 
H("i.  PEEP  15  cm  H.O,  PC  30  cm  H.O    Other  than  the  CPAP  setting,  a  rate  of  15  and  Ti  of  2  s 
were  used    The  ventilator  was  attached  to  ,i  Michigan  Instruments  test  lung  (resistance  =  20  cm 
H-O  L  s,  compliance  -  20  mL'cm  H.O)    The  gas  from  the  ventilator  was  not  humidified    The 
analyzer  was  inserted  into  the  inspiratory  limb  of  the  circuit  using  either  a  sidestream  or 
mainstream  technique    Measurements  of  NO  and  NO>  were  also  performed  usinj;  a  calibrated 
tcophv  sics  Chcmi'uminesenl  analyzer    Bias  ±  precision  were  used  to  compare  the  [NO)  from 
the  chemilumineseenLc  and  dec lrncheniiL.il  analv/ers     Results:  Bias  i  precision  were 


ana,v,er 

overall 

[NO]  (ppm) 

Peak  Pressure  (cm  hoi 

1  li  i 

■:  20  ppm 

■  M  ppm 

i.i' 

22  *     -.11 

. "  <     J  < 

s  0  50  J 

(I  5(1 

Saan 

Oil  ± 
0  67 

•0  03  i 
037 

0  27  1 
087 

0.09  1 
0  94 

on* 
0  57 

I)  12  t 
0.38 

0  I2± 
0  72 

0  09t 

.1  58 

Pulmonox 

1  83  i 
1  87 

0  95  t 
073 

2  88  » 
224 

1  30 

1  53  » 
Id 

2    '" 

2.16 

'o'w* 

NOxBOX 

•0  77  i 
1  04 

■0  25  | 
0  67 

-1  38  . 

1  (17 

1  34  i 
1  43 

0MJ 

'(1 

■0   18 

(I  ■■  1 

1  13 

-0  39  i 
0  75 

There  were  significant  differences  m  bias  between  the  analv/crs  (P     0  001 )    lor  the  Saan,  there 
was  no  significant  difference  in  bias  for  pressure  (P     0.99  (or  FIOj  (P  -  0  8).  and  a  small  hut 
significant  difference  for  [NO|  (P     0  03)    For  the  Pulmonox.  there  were  significant  differences 

i$ure(P     0.001),  I  KMP     0.002),  and  [NO)  (P<  0.001).  For  the  NOxBOX. 
ft  n  wen  ilio  significant  differences  in  bias  for  pressure  (P    0.0002),  FIOj  (P  0.004),  and 

[NO]  (P  ■   0  001 1    Concfaslou:    Despite  differences  between  devices,  the  bias  and  precision  of 
these  analyzers  ma)  he  acceptable  for  clinical  use    The  devices  lended  to  he  most  accurate  at 
|NO)  s  20  ppm,  higher  airw.is  pressures  and  higher  HO.  levels  -  the  clinical  conditions  at 
which  NO  is  most  commonly  used    Considering  that  electrochemical  NO  analyzers  have  only 
been  available  for  several  yean  Ehl  Si  i  un<  '■  Uld  precision  of  these  devices  is  exceptional 
(Supported  in  part  by  Puritan-Bcnncll) 

OF-95-100 


EVALUATION  OF  FOUR  INHALED  NITRIC  OXIDE  THERAPY  ANALYZERS 
USING  KNOWN  CONCENTRATIONS  OF  NITROGEN  DIOXIDE 
Peter  Beat  RRT,  Barry  Grcnier  RRT,  John  Thompson  RRT  Respiratory  Care 
Department,  Children's  Hospital.  Boston.  MA. 

We  previously  evaluated  4  analyzers  that  are  used  to  monitor  nunc  oxide  (NO)  and 
nitrogen  dioxide  (NO2)  concentrations  during  inhaled  NO  therapy.  NO  readings  were 
accurate  in  all  4  analyzes  but  NO2  readings  differed  between  analyzers.  NO;  readings 
obtained  from  two  side-stream  (SS)  analyzers  were  significantly  higher  than  readings  from 
two  main-stream  (MS)  analyzers  (p<001)  We  speculated  that  the  sample  technique 
accounted  for  these  differences  A  second  study  w  as  conducted  to  verity  the  accuracy  of 
these  analyzers  using  known  concentrauons  ol  NC*2  Three  e  tec  troche  rmcai  ( EC)  models, 
Pulmonox  II  (PMX).  Bedfont  NOxBOX  (BFX)  and  Drager  190  NO2  (DRG),  and  one 
chemiluminescence  (CL)  device;  Thermoenvironmental  42M  (THM)  were  studied.  The 
BFX  and  the  42H  arc  SS  and  the  PMX  and  DRG  are  MS.  All  four  analyzers  were 
calibrated  according  to  the  manufacturers'  specifications  The  EC  devices  were  calibrated  at 
25  cmH20  pressure.  NO2  from  a  1 2.5  ppm  source  tank  was  utraicd  into  the  inspiratory' 
limb  of  an  infant  ventilator  ( VIP  Bird).  NO^ concentrations  were  determined  from  the 
equation    N02_caLC=  NO2  Source»NC>2   V  /  NOj   V  +  Ventilator  V  NO?  V  and 
ventilator  V  were  verified  and  5  NOj  concentrauons  ranging  from  I  to  8  ppm  were  used. 
Thc  ventilator,  connected  to  a  test  lung,  was  set  in  the  time  cycled  IMV  mode  at  a 
PiP/PEEPof  30/5cmH2O.  rate  25.  Ti  0  6  sees  and  an  F1O3  of  .21.  All  exhausted  gases 
were  scavenged  Each  anaJyzer  was  studied  independently  and  NO;  measurements  were 
recorded  after  five  minutes  of  stabilization  The  study  was  repeated  three  tames  and  mean 
values  used  for  analysis.  Vcnulator  settings  were  observed  and  remained  stable  throughout 
the  study  NO2  measurements  were  compared  to  NO2-CALC    There  was  a  strong 
correlation  between  measured  NOj  levels  and  NCH-CALC  in  ^  d  monitors. 


PMX 


bia 

♦/-  precision 

.  16±.75 

.1 

[s  of  agreement 

-104  1OI.36 

BFX 


-.70  to  12 


DRG 


THM 


All  4  analyzers  provide  accurate  NCh  readings  in  a  NGWnwm  air  gas  mixture  free  of  NO 
This  data  further  supports  the  theory  that  the  sampling  technique  may  influence  the  NO2 
readings  Relatively  long  sample  lines  and  slow  sample  flow  rates  used  in  the  SS 
analyzers,  may  increase  the  dwell  Qmc  of  NO  and  On  and  result  in  falsely  high  NO; 
readings  Further  investigation  is  required  to  identify  the  effect  of  sampling  technique  on 
NO;  readings  with  these  analyzers 


1 1 86 


Respiratory  Care  •  novkmhi-k  '95  vol  40  No  11 


Monday,  December  4,  12:45-2:40  pm  {Rooms  230C-D) 


EVALUATION  OF  FOUR  ANALYZERS  USED  TO  MONITOR  INHALED  NITRIC 
OXIDE  THERAPY.  Peter  Betil  RRT.  Barry  Grcnier  RRT.  John  Thompson  RRT 
Respiratory  Care  Department,  Children's  Hospital.  Boston,  MA. 

The  verification  of  mine  oude  (NO)  doses  and  the  measurement  of  nitrogen  dioxide  (NO2) 
levels  is  essential  in  evaluadng  physiologic  response  and  ensuring  safe  delivery  during 
inhaled  NO  therapy  Wc  evaluated  four  commercially  available  NO/NO2  analyzers,  three 
electrochemical  (EQ  models,  Pulmonox  II  (PMX),  Bedfont  NOxBOX  (BFX)  and  Dragcr 
PacII  NO  &  190  NO2  (DRG),  and  one  chenu luminescence  device;  ThermoenvironmcntaJ 
42M  (THM).  All  four  analyzers  were  calibrated  according  to  the  manufacturers' 
specifications.  The  EC  devices  were  calibrated  at  25  cml-^O  pressure.  NO  from  an  800 
ppm  source  tank  was  titrated  into  the  inspiratory  limb  of  an  infant  ventilator  (VIP  Bird) 
NO  ooncentranons  were  determined  from  the  equation:  NO^ALC  =  NO  Source  »NO  V  / 
NO  V  +  Ventilator  V.  NO  V  and  ventilator  V  were  verified  and  7  NOdoses  ranging  from  3 
to  80  ppm  were  used.  The  ventilator,  connected  to  a  lest  lung,  was  set  in  the  time  cycled 
IMV  mode  at  a  PiP/PEEP  of  30/5  cmH20.  rate  25,  and  Ti  0.6  sees.  NO  and  NO2  levels 
were  measured  and  recorded  lor  each  NOcajx  and  at  a  set  F1O2  of  .30,  60  and  1.0  Each 
analyzer  was  studied  independently  and  measurements  were  recorded  after  five  minutes  of 
stabilization.  The  study  was  repeated  three  times  and  mean  values  used  for  analysis. 
Ventilator  settings  were  observed  and  remained  stable  throughout  the  study.  NO 
measurements  were  compared  to  NOfALC  and  NCH  lev  els  were  compared  between  each 
analyzer  There  was  a  strong  correlation  between  measured  NO  levels  and  NOcALC  in  a"  4 
analyzers  (Table  1).  NO2  measurements  at  NO  levels  >  40  ppm  are  reported  in  Table  2. 
The  BFX  and  THM  are  side-stream  analyzers  and  measured  signjfieanUy  higher  NOo  levels 
than  the  PMX  and  DRG  which  are  main-stream  analyzers  (p  <.001 ) 


Table  1:  CorrclaDon  between  measured  NO  and  NOtai  r 

DRG 

1.0 

1.4±1.09 

-338  10  6.18 

PRO 

52*.  17 
.72*20 
99*33 

correlation 
bias±precision 
limits  of  agreement 

Table  2:  NO?  measur 

PMX 

.999 

-.06*1.13 

-5.04  10  4 91 

BFX 
1.0 

-67±34 
-2. 15  to  .81 

an±SD 

THM 
.997 
1.01*1.11 

-3.85  to  5.87 

NQcalc 
40 
60 
80 

PMX 
21±.08 
.29t08 
.S4±,17 

BFX 
l.Oi.25 
1.7*51 
2.4±.65 

THM 
1.14*  .36 
2.60*1.11 
3  40*1.47 

All  4  analyzers  produced  precise  and  aecurale  NO  measurements  and  are  suitable  for  the 
clinical  monitoring  of  inhaled  NO  doses.  The  different  NOo  levels  may  be  due  to  sampling 
technique.  The  BFX  and  THM  sample  lines  and  slow  sample  flow  rates  may  be  a  source 
for  additional  NO7  production  and  may  result  in  falsely  high  NCH  readings  The  effect  on 
NO2  readings  that  a  decreased  sample  line  length  and  lumen,  and  increased  sample  flow 
rate,  would  have  on  the  side-stream  analyzers  needs  further  investigation  The  choice  of 
mom  tor  will  depend  on  other  factors  such  as  cost,  portability,  availability  of  alarms  and 


SMOKING 
CESSATION 


Intervention  Techniques  for  the 
Respiratory  Care  Practitioner 

Covers  four  major  aspects  of  smoking  cessation  -  the  impact  of 
smoking  on  illness  and  mortality,  behavioral  components, 
current  cessation  programs,  and  effective  intervention.  A  one 
hour  videotape  lecture  by  Kathleen  A.  Smalky,  MD,  MPH. 

Item  VT35-  $35  ($40  nonmembers).  Add  $4.50  for  shipping. 


To  Order  Call  (214)  243-2272 
or  Fax  to  (214)  484-2720 


Accept  NO  SUBSTITUTE! 

For  relief  from  dry,  cracking 
nasal  passages  associated  with  oxygen  use. 


«fl 


oEzIt 

is  a  formulae  created  by 

professionals  in  both  the 

Medical  and  Cosmetic 

Industry,  combining  the 

unique  properties  of 

Aloe  and  Emu  Oil. 


By  applying  ROEZIT*  to  the  nasal  passages  before  and 
during  0:  use,  this  can  relieve  the  discomfort  that  is  cre- 
ated over  long-term  use  that  has  been  documented  by 
care  givers  for  decades. 

ROEZIT*  is  proud  to  be  a  pioneer  in  addressing  this 
nagging  problem. 

Clinically  tested  by  NAmSa,  world  leader  in  testing  svc. 
for  the  medical  device  industry.  All  Federal  Safety 
Guidelines  were  followed.  Meets  USP  requirements. 

Distributed  by:  LuSal  Enterprises  Inc. 

802  Dominion  Dr.,  Ste.  100  •  Katy,  TX  77450  •  80O426-7139 

Call  for  Your  Free  Sample 


Circle  162  on  reader  service  card 
Visit  AARC  Booth  1404  in  Orlando 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1187 


A  different  outlook  for  your  patients 
with  asthma 


Provides  12  hours 
of  asthma  symptom 
control12 


Prevents 
bronchospasm 
from  occurring 


SEREVENT  is  indicated  for  maintenance  treatment 
of  asthma  and  prevention  of  bronchospasm  in 
patients  12  years  of  age  and  older  with  reversible 
obstructive  airway  disease,  including  patients  with 
symptoms  of  nocturnal  asthma,  who  require  regular 
treatment  with  inhaled,  short-acting  B2- agonists. 
SEREVENT  is  also  indicated  for  prevention  of  exercise- 
induced  bronchospasm  (EIB)  in  patients  12  years  of 
age  and  older. 

Dosing  should  be  two  puffs  (42  jjg)  of  SEREVENT 
twice  daily,  morning  and  evening,  approximately 
12  hours  apart.  For  prevention  of  EIB,  dosing  should 
be  two  puffs  (42  ug)  at  least  30  to  60  minutes  before 
exercise. 

Patients  being  treated  with  SEREVENT  twice  daily, 
morning  and  evening,  approximately  12  hours 
apart,  should  not  use  additional  SEREVENT  before 
exercising. 

IMPORTANT  INFORMATION: 

SEREVENT  SHOULD  NOT  BE  INITIATED  IN  PATIENTS 
WITH  SIGNIFICANTLY  WORSENING  OR  ACUTELY 
DETERIORATING  ASTHMA,  WHICH  MAY  BE  A  LIFE- 
THREATENING  CONDITION. 

SEREVENT  SHOULD  NOT  BE  USED  TO  TREAT  ACUTE 
SYMPTOMS.  Patients  must  be  provided  with  a 
short-acting,  inhaled  &2-  agonist  for  treatment 
of  acute  symptoms. 

SEREVENT  IS  NOT  A  SUBSTITUTE  FOR  INHALED  OR 
ORAL  CORTICOSTEROIDS. 


Circle  109  on  reader  service  card 
Visit  AARC  Booth  612  in  Orlando 


Twice-Daily 


Please  consult  Brief  Summary  of 
Prescribing  Information  on  adjacent  pages. 


Serevent 

(solmeterol  xinofoate) 

Inhalation  Aerosol 

Morning  and  Evening  Inhalation 
for  Active  Days  and  Restful  Nights 


SereVent 

(solmeterol  xinafoate) 


Serevent®  BRIEF  SUMMARY 

(salmeterol  xinafoate) 
Inhalation  Aerosol 

Bronchodilator  Aerosol 
For  Oral  Inhalation  Only 

The  following  is  a  brief  summary  only.  Before  prescribing,  see  complete  prescribing  information  in 
Serevent®  Inhalation  Aerosol  product  labeling. 

CONTRAINDICATIONS:  Serevent"-  Inhalation  Aerosol  is  contramdicated  in  patients  with  a  history  of 
hypersensitivity  to  any  of  the  components. 

WARNINGS: 

IMPORTANT  INFORMATION:  SEREVENT   INHALATION  AEROSOL  SHOULD  NOT  BE  INITIATED  IN 
PATIENTS  WITH  SIGNIFICANTLY  WORSENING  OR  ACUTELY  DETERIORATING  ASTHMA,  WHICH 
MAY  BE  A  LIFE-THREATENING  CONDITION.  Serious  acute  respiratory  events,  including  fatali- 
ties, have  been  reported,  both  in  the  US  and  worldwide,  when  Serevent  Inhalation  Aerosol 
has  been  Initiated  in  this  situation. 

Although  it  is  not  possible  from  these  reports  to  determine  whether  Serevent  Inhalation 
Aerosol  contributed  to  these  adverse  events  or  simply  failed  to  relieve  the  deteriorating 
asthma,  the  use  of  Serevent  Inhalation  Aerosol  in  this  setting  is  inappropriate. 

SEREVENT  INHALATION  AEROSOL  SHOULD  NOT  BE  USED  TO  TREAT  ACUTE  SYMPTOMS.  It  is 
crucial  to  inform  patients  of  this  and  prescribe  a  short-acting,  inhaled  hetar  agonist  for  this 
purpose  as  well  as  warn  them  that  increasing  inhaled  beta2-agonist  use  is  a  signal  of  dete- 
riorating asthma. 

SEREVENT  INHALATION  AEROSOL  IS  NOT  A  SUBSTITUTE  FOR  INHALED  OR  ORAL  CORTICO- 
STEROIDS. Corticosteroids  should  not  be  stopped  or  reduced  when  Serevent  Inhalation 
Aerosol  is  initiated. 

(See  PRECAUTIONS:  Information  for  Patients  section  of  the  full  prescribing  information 
and  the  separate  PATIENT'S  INSTRUCTIONS  FOR  USE  leaflet.) 

1 .  Do  Not  Introduce  Serevent  Inhalation  Aerosol  as  a  Treatment  for  Acutely  Deteriorating  Asthma: 
Serevent  Inhalation  Aerosol  is  intended  for  the  maintenance  treatment  of  asthma  (see  INDICATIONS 
and  USAGE  section  of  the  full  prescribing  information)  and  should  not  be  introduced  in  acutely  dete- 
riorating asthma,  which  is  a  potentially  life-threatening  condition.  There  are  no  data  demonstrating 
that  Serevent  Inhalation  Aerosol  provides  greater  efficacy  than  or  additional  efficacy  to  short-acting, 
inhaled  beta2-agonists  in  patients  with  worsening  asthma.  Serious  acute  respiratory  events,  includ- 
ing fatalities,  have  been  reported,  both  in  the  US  and  worldwide,  in  patients  receiving  Serevent 
Inhalation  Aerosol  In  most  cases,  these  have  occurred  in  patients  with  severe  asthma  (e.g., 
patients  with  a  history  of  corticosteroid  dependence,  low  pulmonary  function,  intubation,  mechani- 
cal ventilation,  frequent  hospitalizations,  or  previous  life-threatening  acute  asthma  exacerbations) 
and/or  in  some  patients  in  whom  asthma  has  been  acutely  deteriorating  (eg ,  unresponsive  to 
usual  medications,  increasing  need  for  Inhaled  short-acting  beta2-agonists,  increasing  need  for  sys- 
temic corticosteroids,  significant  increase  in  symptoms,  recent  emergency  room  visits,  sudden  or 
progressive  deterioration  in  pulmonary  function)  However,  they  have  occurred  in  a  few  patients 
with  less  severe  asthma  as  well  It  was  not  possible  from  these  reports  to  determine  whether 
Serevent  Inhalation  Aerosol  contributed  to  these  events  or  simply  failed  to  relieve  the  deteriorating 
asthma 

2  Do  Not  Use  prevent  Inhalation  Aerosol  to  Treat  Acute  Symptoms  A  short-acting,  inhaled  bela.. 
agonist,  not  Serevent  Inhalation  Aerosol,  should  be  used  to  relieve  acute  asthma  symptoms  When 
prescribing  Serevent  Inhalation  Aerosol,  the  physician  must  also  provide  the  patient  with  a  short- 
acting,  Inhaled  beta2-agonist  (e.g.,  albuterol)  for  treatment  ot  symptoms  that  occur  acutely,  despite 
regular  twice  daily  Imorning  and  evening)  use  of  Serevent  Inhalation  Aerosol 

When  beginning  treatment  with  Serevent  Inhalation  Aerosol,  patients  who  have  been  taking  short- 
acting,  Inhaled  beta2-agonlsts  on  a  regular  basis  (e.g.,  q.i.d.)  should  be  instructed  to  discontinue  the 
regular  use  of  these  drugs  and  use  them  only  for  symptomatic  relief  il  they  develop  acute  asthma 
symptoms  while  taking  Serevent  Inhalation  Aerosol  Isee  PRECAUTIONS  Information  for  Patients) 

3  Watch  lor  Increasing  Use  ot  Short  Acting,  Inhaled  Beta,2-Agonists.  Which  Is  a  Marker  of 
Deteriorating  Asthma  Asthma  may  deteriorate  acutely  over  a  period  ot  hours  or  chronically  over 

oi  longer  It  the  patient's  short-acting,  inhaled  beta2-agonist  becomes  less  effective  or 
the  patient  needs  more  Inhalations  than  usual,  this  may  be  a  marker  ot  destabilizatioo  of  asthma.  In 
this  setting,  the  patient  requires  Immediate  re-evaluation  with  reassessment  of  the  treatment  regi- 
men, giving  special  consideration  to  the  possible  need  lor  corticosteroids  If  the  patient  uses  four  or 
more  Inhalations  per  day  of  a  short-acting,  inhaled  beta2-agonlst  for  2  or  more  consecutive  days,  or 


Serevent   (salmeterol  xinafoate)  Inhalation  Aerosol 

if  more  than  one  canister  (200  inhalations  per  canister)  of  short-acting,  inhaled  beta2-agonist  is  used 
in  an  8-week  penod  in  conjunction  witti  Serevent  Inhalation  Aerosol,  then  the  patient  should  consult 
the  physician  for  re-evaluation  Increasing  the  daily  dosage  of  Serevent  Inhalation  Aerosol  in  this 
situation  is  not  appropriate.  Serevent  Inhalation  Aerosol  should  not  be  used  more  frequently 
than  twice  daily  (morning  and  evening)  at  the  recommended  dose  of  two  inhalations. 
4.  Do  Not  Use  Serevent  Inhalation  Aerosol  as_a  Substitute  tor  Oral  or  Inhaled  Corticosteroids:  There 
are  no  data  demonstrating  that  Serevent  Inhalation  Aerosol  has  a  clinical  anti-inflammatory  effect 
and  could  be  expected  to  take  the  place  of,  or  reduce  the  dose  of  corticosteroids.  Patients  who 
already  require  oral  or  inhaled  corticosteroids  for  treatment  of  asthma  should  be  continued  on  this  j 
type  ot  treatment  even  if  they  feel  better  as  a  result  of  initiating  Serevent  Inhalation  Aerosol.  Any 
change  in  corticosteroid  dosage  should  be  made  ONLY  after  clinical  evaluation  (see  PRECAUTIONS: 
Information  for  Patients). 

5  Do  Not  Exceed  Recommended  Dosage  As  with  other  inhaled  beta2-adrenergic  drugs.  Serevent 
Inhalation  Aerosol  should  not  be  used  more  often  or  at  higher  doses  than  recommended.  Fatalities 
have  been  reported  in  association  with  excessive  use  of  inhaled  sympathomimetic  drugs.  Large 
doses  of  inhaled  or  oral  salmeterol  (12  to  20  times  the  recommended  dose)  have  been  associated 
with  clinically  significant  prolongation  of  the  OT  interval,  which  has  the  potential  for  producing  ven- 
tricular arrhythmias 

6  Paradoxical  Bronchospasm  As  with  other  inhaled  asthma  medication,  paradoxical  bron- 
chospasm  (which  can  be  life  threatening)  has  been  reported  following  the  use  of  Serevent 
Inhalation  Aerosol.  If  it  occurs,  treatment  with  Serevent  Inhalation  Aerosol  should  be  discontinued 
immediately  and  alternative  therapy  instituted. 

7  Immediate  Hypersensitivity  Reactions:  Immediate  hypersensitivity  reactions  may  occur  after 
administration  ol  Serevent  Inhalation  Aerosol,  as  demonstrated  by  rare  cases  of  urticaria, 
angioedema,  rash,  and  bronchospasm. 

8  Upper  Airway  Symptoms:  Symptoms  of  laryngeal  spasm,  irritation,  or  swelling,  such  as  stridor 
and  choking,  have  been  reported  rarely  in  patients  receiving  Serevent  Inhalation  Aerosol. 
PRECAUTIONS: 

General:  1  Use  With  Spacer  or  Other  Devices:  The  safety  and  effectiveness  of  Serevent*  Inhalation 
Aerosol  when  used  with  a  spacer  or  other  devices  have  not  been  adeguately  studied. 

2.  Cardiovascular  and  Other  Effects:  No  effect  on  the  cardiovascular  system  is  usually  seen  after 
the  administration  of  inhaled  salmeterol  in  recommended  doses,  but  the  cardiovascular  and  central 
nervous  system  effects  seen  with  all  sympathomimetic  drugs  (e.g ,  increased  blood  pressure,  heart 
rate,  excitement)  can  occur  after  use  of  Serevent  Inhalation  Aerosol  and  may  require  discontinuation 
of  the  drug.  Salmeterol,  like  all  sympathomimetic  amines,  should  be  used  with  caution  in  patients 
with  cardiovascular  disorders,  especially  coronary  insufficiency,  cardiac  arrhythmias,  and  hyperten- 
sion; in  patients  with  convulsive  disorders  or  thyrotoxicosis;  and  in  patients  who  are  unusually 
responsive  to  sympathomimetic  amines. 

As  has  been  described  with  other  beta-adrenergic  agonist  bronchodilators,  clinically  significant 
changes  in  systolic  and/or  diastolic  blood  pressure,  pulse  rate,  and  electrocardiograms  have  been 
seen  infrequently  in  individual  patients  in  controlled  clinical  studies  with  salmeterol. 

3  Metabolic  Effects:  Doses  of  the  related  beta2-adrenoceptor  agonist  albuterol,  when  adminis- 
tered intravenously,  have  been  reported  to  aggravate  pre-existing  diabetes  mellitus  and  ketoacido- 
sis. No  effects  on  glucose  have  been  seen  with  Serevent  Inhalation  Aerosol  at  recommended  doses. 
Administration  of  beta2-adrenoceptor  agonists  may  cause  a  decrease  in  serum  potassium,  possibly 
through  intracellular  shunting,  which  has  the  potential  to  increase  the  likelihood  of  arrhythmias.  The 
decrease  is  usually  transient,  not  requiring  supplementation 

Clinically  significant  changes  in  blood  glucose  and/or  serum  potassium  were  seen  rarely  during 
clinical  studies  with  long-term  administration  of  Serevent  Inhalation  Aerosol  at  recommended  doses. 
Information  for  Patients:  See  illustrated  Patient's  Instructions  for  Use  leaflet  SHAKE  WELL 
BEFORE  USING 

It  is  important  that  patients  understand  how  to  use  Serevent  Inhalation  Aerosol  appropriately  and 
how  it  should  be  used  in  relation  to  other  asthma  medications  they  are  taking.  Patients  should  be 
given  the  following  information: 
1 .  Shake  well  before  using. 


3.  Serevent  Inhalation  Aerosol  is  not  meant  to  relieve  acute  asthma  symptoms  and  extra  doses 
should  not  be  used  for  that  purpose  Acute  symptoms  should  be  treated  with  a  short-acting, 
inhaled  beta2-agonist  such  as  albuterol  (the  physician  should  provide  the  patient  with  such  med- 
ication and  instruct  the  patient  in  how  it  should  be  used). 

4.  The  physician  should  be  notified  immediately  if  any  of  the  following  situations  occur,  which  may 
be  a  sign  of  seriously  worsening  asthma. 

•  Decreasing  effectiveness  of  short-acting,  inhaled  beta2-agonists 

•  Need  for  more  inhalations  than  usual  of  short-acting,  inhaled  beta2-agonists 

•  Use  of  four  or  more  inhalations  per  day  ot  a  short-acting  beta2-agonist  for  2  or  more  days 
consecutively 

•  Use  of  more  than  one  canister  of  a  short-acting,  inhaled  beta2-agonist  in  an  8-week  penod 
(i.e.,  canister  with  200  inhalations) 

5.  Serevent  Inhalation  Aerosol  should  not  be  used  as  a  substitute  for  oral  or  inhaled  corticosteroids. 
The  dosage  of  these  medications  should  not  be  changed  and  they  should  not  be  stopped  without 
consulting  the  physician,  even  if  the  patient  feels  better  after  initiating  treatment  with  Serevent 
Inhalation  Aerosol. 

6  Patients  should  be  cautioned  regarding  potential  adverse  cardiovascular  effects,  such  as  palpita- 
tions or  chest  pain,  related  to  the  use  of  additional  beta2-agonist. 

7  In  patients  receiving  Serevent  Inhalation  Aerosol,  other  inhaled  medications  should  be  used  only 
as  directed  by  the  physician. 

8  When  using  Serevent  Inhalation  Aerosol  to  prevent  exercise-induced  bronchospasm,  patients 
should  take  the  dose  at  least  30  to  60  minutes  before  exercise. 

Drug  Interactions:  Short-Acting  Beta-Agonists:  In  the  two  3-month,  repetitive-dose  clinical  trials 
(n=184),  the  mean  daily  need  lor  additional  beta2  agonist  use  was  1  to  1  'h  inhalations  per  day,  but 
some  patients  used  more  Eight  percent  of  patients  used  at  least  eight  inhalations  per  day  at  least 
on  one  occasion  Six  percent  used  9  to  12  inhalations  at  least  once  There  were  15  patients  (8%) 
who  averaged  over  (our  inhalations  per  day  Four  of  these  used  an  average  ot  8  to  1 1  inhalations 
per  day.  In  these  1 5  patients  there  was  no  observed  increase  in  freguency  of  cardiovascular  adverse 


Serevent   (salmeterol  xinafoate)  Inhalation  Aerosol 

events  The  safety  of  concomitant  use  of  more  than  eight  inhalations  per  day  of  short-acting 
beta2-agonists  with  Serevent  Inhalation  Aerosol  has  not  been  established  In  1 5  patients  who  expe- 
rienced worsening  of  asthma  while  receiving  Serevent  Inhalation  Aerosol,  nebulized  albuterol  (one 
dose  in  most)  led  to  improvement  in  forced  expiratory  volume  in  1  second  (FEV,)  and  no  increase  in 
occurrence  of  cardiovascular  adverse  events. 

Monoamine  Oxidase  Inhibitors  and  Tricyclic  Antidepressants:  Salmeterol  should  be  adminis- 
tered with  extreme  caution  to  patients  being  treated  with  monoamine  oxidase  inhibitors  or  tricyclic 
antidepressants  because  the  action  of  salmeterol  on  the  vascular  system  may  be  potentiated  by 
these  agents 

Corticosteroids  and  Cromoglycate:  In  clinical  trials,  inhaled  corticosteroids  and/or  inhaled  cro- 
molyn sodium  did  not  alter  the  safety  profile  of  Serevent  Inhalation  Aerosol  when  administered  con- 
currently. 

Methylxanthines:  The  concurrent  use  of  intravenously  or  orally  administered  methylxanthines 
(e.g..  aminophylline,  theophylline!  by  patients  receiving  Serevent  Inhalation  Aerosol  has  not  been 
completely  evaluated.  In  one  clinical  trial,  87  patients  receiving  Serevent  Inhalation  Aerosol  42  meg 
twice  daily  concurrently  with  a  theophylline  product  had  adverse  event  rates  similar  to  those  in  71 
patients  receiving  Serevent  Inhalation  Aerosol  without  theophylline.  Resting  heart  rates  were  slightly 
higher  in  the  patients  on  theophylline  but  were  little  affected  by  Serevent  Inhalation  Aerosol  therapy. 

Carcinogenesis,  Mutagenesis,  Impairment  of  Fertility:  In  an  18-month  oral  carcinogenicity  study 
in  CD-mice,  salmeterol  xinafoate  caused  a  dose-related  increase  in  the  incidence  of  smooth  muscle 
hyperplasia,  cystic  glandular  hyperplasia,  and  leiomyomas  of  the  uterus  and  a  dose-related  increase 
in  the  incidence  of  cysts  in  the  ovaries  A  higher  incidence  of  leiomyosarcomas  was  not  statistically 
significant;  tumor  findings  were  observed  at  oral  doses  of  1  4  and  1 0  mg/kg,  which  gave  9  and  63 
times,  respectively,  the  human  exposure  based  on  rodenthuman  AUC  comparisons 

Salmeterol  caused  a  dose-related  increase  in  the  incidence  of  mesovanan  leiomyomas  and  ovar- 
ian cysts  in  Sprague  Dawley  rats  in  a  24-month  inhalation/oral  carcinogenicity  study  Tumors  were 
observed  in  rats  receiving  doses  of  0  68  and  2  58  mg/kg  per  day  (about  55  and  215  times  the  rec- 
ommended clinical  dose  [mg/nv]).  These  findings  in  rodents  are  similar  to  those  reported  previously 
for  other  beta-adrenergic  agonist  drugs  The  relevance  of  these  findings  to  human  use  is  unknown 

No  significant  effects  occurred  in  mice  at  0  2  mg/kg  (1  3  times  the  recommended  clinical  dose 
based  on  comparisons  of  the  AUCs)  and  in  rats  at  0.21  mg/kg  (15  times  the  recommended  clinical 
dose  on  a  mg/nr'  basis) 

Salmeterol  xinafoate  produced  no  detectable  or  reproducible  increases  in  microbial  and  mam- 
malian gene  mutation  in  vitro  No  blastogenic  activity  occurred  in  vitro  in  human  lymphocytes  or  in 
vivo  in  a  rat  micronucleus  test.  No  effects  on  fertility  were  identified  in  male  and  female  rats  treated 
orally  with  salmeterol  xinafoate  at  doses  up  to  2  mg/kg  orally  (about  160  times  the  recommended 
clinical  dose  on  a  mg/nf  basis) 

Pregnancy:  Teratogenic  Effects:  Pregnancy  Category  C:  No  significant  effects  of  maternal  expo- 
sure to  oral  salmeterol  xinafoate  occurred  in  the  rat  at  doses  up  to  the  equivalent  of  about  160 
times  the  recommended  clinical  dose  on  a  mg/nv  basis  Dutch  rabbit  fetuses  exposed  to  salmeterol 
xinafoate  in  utero  exhibited  effects  characteristically  resulting  from  beta-adrenoceptor  stimulation; 
these  included  precocious  eyelid  openings,  cleft  palate,  sternebral  fusion,  limb  and  paw  flexures, 
and  delayed  ossification  of  the  frontal  cranial  bones  No  significant  effects  occurred  at  0.6  mg/kg 
given  orally  (12  times  the  recommended  clinical  dose  based  on  comparison  of  the  AUCs) 

New  Zealand  White  rabbits  were  less  sensitive  since  only  delayed  ossification  of  the  frontal 
bones  was  seen  at  10  mg/kg  given  orally  (approximately  1 ,600  times  the  recommended  clinical 
dose  on  a  mg/m'  basis)  Extensive  use  of  other  beta-agonists  has  provided  no  evidence  that  these 
class  effects  in  animals  are  relevant  to  use  in  humans  There  are  no  adequate  and  well-controlled 
studies  with  Serevent  Inhalation  Aerosol  in  pregnant  women  Serevent  Inhalation  Aerosol  should  be 
used  during  pregnancy  only  if  the  potential  benefit  justifies  the  potential  risk  to  the  fetus. 

Use  in  Labor  and  Delivery:  There  are  no  well-controlled  human  studies  that  have  investigated 
effects  of  salmeterol  on  preterm  labor  or  labor  at  term.  Because  of  the  potential  for  beta-agonist 
interference  with  uterine  contractility,  use  of  Serevent  Inhalation  Aerosol  during  labor  should  be 
restricted  to  those  patients  in  whom  the  benefits  clearly  outweigh  the  risks 

Nursing  Mothers:  Plasma  levels  of  salmeterol  after  inhaled  therapeutic  doses  are  very  low  (85  to 
200  pg/mL)  in  humans  In  lactating  rats  dosed  with  radiolabeled  salmeterol,  levels  of  radioactivity 
were  similar  in  plasma  and  milk.  In  rats,  concentrations  of  salmeterol  in  plasma  and  milk  were  sim- 
ilar The  xinafoate  moiety  is  also  transferred  to  milk  in  rats  at  concentrations  of  about  half  the  corre- 
sponding level  in  plasma  However,  since  there  is  no  experience  with  use  of  Serevent  Inhalation 
Aerosol  by  nursing  mothers,  a  decision  should  be  made  whether  to  discontinue  nursing  or  to  dis- 
continue the  drug,  taking  into  account  the  importance  of  the  drug  to  the  mother  Caution  should  be 
exercised  when  salmeterol  xinafoate  is  administered  to  a  nursing  woman 

Pediatric  Use:  The  safety  and  effectiveness  of  Serevent  Inhalation  Aerosol  in  children  younger  than 
12  years  of  age  have  not  been  established. 

Geriatric  Use:  Of  the  total  number  of  patients  who  received  Serevent  Inhalation  Aerosol  in  all  clini- 
cal studies,  241  were  65  years  and  older  Geriatric  patients  (65  years  and  older)  with  reversible 
obstructive  airway  disease  were  evaluated  in  four  well-controlled  studies  of  3  weeks'  to  3  months' 
duration  Two  placebo-controlled,  crossover  studies  evaluated  twice-daily  dosing  with  salmeterol  for 
21  to  28  days  in  45  patients  An  additional  75  geriatric  patients  were  treated  with  salmeterol  for  3 
months  in  two  large  parallel-group,  multicenter  studies  These  1 20  patients  experienced  increases 
in  AM  and  PM  peak  expiratory  flow  rate  and  decreases  in  diurnal  variation  in  peak  expiratory  flow 
rate  similar  to  responses  seen  in  the  total  populations  of  the  two  latter  studies  The  adverse  event 
type  and  frequency  in  geriatric  patients  were  not  different  from  those  of  the  total  populations  stud- 
ied. 

No  apparent  differences  in  the  efficacy  and  safety  of  Serevent  Inhalation  Aerosol  were  observed 
when  geriatric  patients  were  compared  with  younger  patients  in  clinical  trials  As  with  other 
beta^-agomsts,  however,  special  caution  should  be  observed  when  using  Serevent  Inhalation 
Aerosol  in  elderly  patients  who  have  concomitant  cardiovascular  disease  that  could  be  adversely 
affected  by  this  class  of  drug  Based  on  available  data,  no  adjustment  of  salmeterol  dosage  in  geri- 
atric patients  is  warranted. 

ADVERSE  REACTIONS:  Adverse  reactions  to  salmeterol  are  similar  in  nature  to  reactions  to  other 
selective  beta2-adrenoceptor  agonists,  i.e.,  tachycardia;  palpitations,  immediate  hypersensitivity 
reactions,  including  urticaria,  angioedema,  rash,  bronchospasm  (see  WARNINGS);  headache;  tremor; 
nervousness;  and  paradoxical  bronchospasm  (see  WARNINGS) 

Two  multicenter,  12-week,  controlled  studies  have  evaluated  twice-daily  doses  of  Serevent® 
Inhalation  Aerosol  in  patients  12  years  of  age  and  older  with  asthma.  The  following  table  reports  the 
incidence  of  adverse  events  in  these  two  studies 


Serevent   (salmeterol  xinafoate)  Inhalation  Aerosol 

Adverse  Experience  Incidence  in  Two  Large  12-Week  Clinical  Trials* 


Adverse  Event  Type 

Percent  of  Patients 

Placebo 

Serevent 

Albuterol 

n=187 

42  meg  bid.  n=184 

180  meg  q. id  n=185 

Ear,  nose,  and  throat 

Upper  respiratory 

tract  infection 

13 

14 

16' 

Nasopharyngitis 

12 

14 

11 

Disease  of  nasal 

cavity/sinus 

4 

6 

1 

Sinus  headache 

2 

4 

<1 

Gastrointestinal 

Stomachache 

0 

4 

0 

Neurological 

Headache 

23 

28 

27 

Tremor 

2 

4 

3 

Respiratory 

Cough 

6 

7 

3 

Lower  respiratory 

infection 

2 

4 

2 

*  The  only  adverse  experience  classified  as  serious  was  one  case  of  upper  respiratory  tract  infection  in  a 
patient  treated  with  albuterol. 

The  table  above  includes  all  events  (whether  considered  drug  related  or  nondrug  related  by  the 
investigator)  that  occurred  at  a  rate  of  over  3%  in  the  Serevent  Inhalation  Aerosol  treatment  group 
and  were  more  common  in  the  Serevent  Inhalation  Aerosol  group  than  in  the  placebo  group. 

Pharyngitis,  allergic  rhinitis,  dizziness/giddiness,  and  influenza  occurred  at  3%  or  more  but  were 
equally  common  on  placebo  Other  events  occurring  in  the  Serevent  Inhalation  Aerosol  treatment 
group  at  a  frequency  of  1%  to  3%  were  as  follows; 

Cardiovascular:  Tachycardia,  palpitations 

Ear,  Nose,  and  Throat  Rhinitis,  laryngitis 

Gastrointestinal:  Nausea,  viral  gastroenteritis,  nausea  and  vomiting,  diarrhea,  abdominal  pain 

Hypersensitivity:  Urticaria 

Mouth  and  Teeth:  Dental  pain 

Musculoskeletal:  Pain  in  joint,  back  pain,  muscle  cramp/contraction,  myalgia/myositis,  muscular 
soreness. 

Neurological:  Nervousness,  malaise/fatigue. 

Respiratory:  Tracheitis/bronchitis. 

Skin:  Rash/skin  eruption. 

Urogenital:  Dysmenorrhea 

In  small  dose-response  studies,  tremor,  nervousness,  and  palpitations  appeared  to  be  dose  related 
Postmarketing  Experience:  In  extensive  US  and  worldwide  postmarketing  experience,  serious 
exacerbations  of  asthma,  including  some  that  have  been  fatal,  have  been  reported  In  most  cases, 
these  have  occurred  in  patients  with  severe  asthma  and/or  in  some  patients  in  whom  asthma  has 
been  acutely  deteriorating  (see  WARNINGS  no  1),  but  they  have  occurred  in  a  few  patients  with 
less  severe  asthma  as  well  It  was  not  possible  from  these  reports  to  determine  whether  Serevent 
Inhalation  Aerosol  contributed  to  these  events  or  simply  failed  to  relieve  the  deteriorating  asthma. 

Postmarketing  experience  includes  rare  reports  of  upper  airway  symptoms  of  laryngeal  spasm, 
irritation,  or  swelling,  such  as  stridor  and  choking. 

OVERDOSAGE:  Overdosage  with  salmeterol  may  be  expected  to  result  in  exaggeration  of  the 
pharmacologic  adverse  effects  associated  with  beta-adrenoceptor  agonists,  including  tachycardia 
and/or  arrhythmia,  tremor,  headache,  and  muscle  cramps  Overdosage  with  salmeterol  can  lead  to 
clinically  significant  prolongation  of  the  QTC  interval,  which  can  produce  ventricular  arrhythmias. 
Other  signs  of  overdosage  may  include  hypokalemia  and  hyperglycemia 

In  these  cases,  therapy  with  Serevent'  Inhalation  Aerosol  and  all  beta-adrenergic-stimulant 
drugs  should  be  stopped,  supportive  therapy  provided,  and  |udicious  use  of  a  beta-adrenergic 
blocking  agent  should  be  considered,  bearing  in  mind  the  possibility  that  such  agents  can  produce 
bronchospasm.  Cardiac  monitoring  is  recommended  in  cases  of  overdosage 

As  with  all  sympathomimetic  pressurized  aerosol  medications,  cardiac  arrest  and  even  death 
may  be  associated  with  abuse  of  Serevent  Inhalation  Aerosol. 

Rats  and  dogs  survived  the  maximum  practicable  inhalation  doses  of  salmeterol  of  2.9  and 
0  7  mg/kg,  respectively.  The  maximum  nonlethal  oral  doses  in  mice  and  rats  were  approximately 
150  mg/kg  and  >1,000  mg/kg,  respectively 

Dialysis  is  not  appropriate  treatment  for  overdosage  of  Serevent  Inhalation  Aerosol 


Allen  SHanburys 


December  1994 
RL-164 

OM.BSS1 


References: 

I.  Peariman  DS.  Chervinsky  P.  LaForce  C.  et  al.  A  comparison  of  salmeterol  with 
albuterol  in  the  treatment  of  mild-to-moderate  asthma.  N  Engl  J  Med.  November 
1992:327:1420-1425  2.  DAIonzo  GE.  Nathan  RA.  Henochowicz  S.  Morris  RJ.  Ratner  P 
Rennard  Si  Salmeterol  xinafoate  as  maintenance  therapy  compared  with  albuterol  in 
patients  with  asthma.  JAMA.  May  1994:271:1412-1416.  3.  Data  on  file.  Glaxo  Inc 
4.  Anderson  SD,  Rodwell  LT,  Du  Toit  J,  Young  IH.  Duration  of  protection  by  inhaled  sal- 
meterol in  exercise-induced  asthma.  Chest.  1991:  IOO:  1254- 1260.  5.  Dhillon  DP.  Studies 
in  exercise-induced  asthma.  Eur  Respir  Rev.  1991: 1 (4). 265-267.  6.  Britton  M.  Salmeterol 
and  salbutamol:  large  multicentre  studies  Eur  Respir  Rev.  l99l:l(4):288-292. 


Allen  &Hanburys 


Glaxo  Wellcome 


Glaxo  Wellcome  In 


SER423R0 


Printed  in  USA 


Monday.  December  4.  3:00-4:55  pm  (Rooms  230A-B) 


EVALUATION  OF  TEN  ADULT  DISPOSABLE  MANUAL 
RESUSCITATORS — Thomas  A  Barnes  EdD  RRT.  Northeastern 
University — Boston,  Massachusetts. 

I  evaluated  the  performance  and  safety  of  ten  adult  disposable  manual  resuscitators 
(DMRs):  Adult  Manual  Resuscitator  (Baxter),  BagEasy  (Respironics),  CPR  Bag 
(Mercury  Medical).  Capno-Flo  (Kirk  Specialty  Systems),  DMR  (Pun tan- Bennett), 
1st  Response  (Sims),  Pulraanex  (Bird),  Spur  (Ambu).  VCare  (Ventlab),  Vital  Blue 
(Vital  Signs).  Method:  I  used  standards  and  methods  approved  by  American 
Society  for  Testing  and  Materials  (F  920-85,  ASTM  Committee  on  Standards, 
Philadelphia  1985:1-22)  and  International  Organization  for  Standardization  (ISO 
8382:1988[E]  prepared  by  Technical  Committee  ISO/TC  121,  Anaesthetic  and 
Respiratory  Equipment,  ISO.  New  York,  1988:1-23).  A  Bio-Tek  VT-1  Ventilator 
Tester  was  used  as  a  lung  model  with  C=  0.02  L/cm  H^O  [0.20  LAPa]  and  R=  20 
cm  H:0.s.L  '  [2  kPa.s.L""].  Results:  All  of  the  DMRs  met  the  ASTM  and  ISO 
standards  for  VT  (600  mL),  f  (20/roin),  and  I:E  (<1 :2).  The  ASTM  and  ISO 
standards  specify  an  FD02  of  £  0.85  with  03  reservoir  and  Onflow  of  15  L/min 
and  VE  of  7.2  L/min  (VT  600  mL,  f  I2/min).  When  tested  for  FD02.  the  Vital 
Blue's  mean  (SD)  was  0.69  (0.02),  which  was  significantly  lower  (p  <  0.001)  than 
the  other  9  DMRs  which  had  an  FDO;  £  0.94.  When  disabled  with  simulated 
vomitus,  all  DMRs  were  able  to  be  restored  to  proper  function  within  20  seconds. 
All  DMRs  except  the  Vital  Blue  were  functional  at  0:  flow  of  30  L/min.  All  DMRs 
passed  tests  for:  forward  and  backward  leakage,  drop  from  1  meter,  and  10-second 
immersion-in- water.  All  DMRs  except  the  CPR  Bag  were  functional  after  storage  at 
temperatures  of  -40°C  and  60°C.  The  CPR  Bag  02  reservoir  had  three  holes  after 
storage  at  -40°C.  All  DMRs  passed  tests  for  inspiratory  and  expiratory  resistance  (< 
-5  cm  FLO  and  <  5  cm  FLO  respectively)  with  gas  flow  to  the  O,  reservoir  of  15 
L/min.  'the  mean  (SD)  expiratory  resistance  for  Vital  Blue  was  38  (2)  cm  H20 
when  gas  flow  to  the  0:  reservoir  was  30  L/min.  The  BagEasy  was  the  only  DMR 
tested  which  met  the  specifications  for  instruction/user  manual.  BagEasy,  Baxter. 
Pulraanex  were  the  only  DMRs  that  prevented  accidental  disassembly.  DMR 
0?uri  tan -Bennett)  and  VCare  do  not  meet  the  FDO,  requirement  if  their  tube-type  0; 
reservoir  is  in  the  collapsed  storage  position.  Conclusions:  I  conclude  that 
BagEasy  meets  the  ASTM  and  ISO  standards  for  minimum  performance  and  safety. 
The  other  DMRs  tested  were  out  of  compliance  with  one  or  more  of  the  ASTM  and 
ISO  requirements.  I  recommend  that  Vital  Blue  not  be  used  when  an  FDO,  of 
>  0.70  is  needed  or  when  oxygen  flow  can  be  set  to  30  L/rain. 


EVALUATION  OF  ADULT  DISPOSABLE  AND  NOND1SPOSABLE  MANUAL  RESUSCITATION  BAGS 

Jeff  Carlson.  RRT.  Jim  Granzo.  RRT.  Butterworth  Hospital .  Grand  Rapids.  Michigan 

This  evaluation  of  adull  manual  resuscitation  bags  IMRB)  was  designed  to  assess  delivered  02  (FD02)  utilizing 

o  follow  American  Soc.ety  of  Testing  and  Materials  (ASTM) 
:d  with  a  lung  model  (Michigan  instrume 
FD02w 


rurer  setup  Testing  was  not  ir 
sF-920-85  Each  resuscitator 
:d  by  computerized  testing  (M 
walyzer  (Catalist  Research.  M 


III  i    Oxygen  flow  at  1 5  1.  Mm  used  for  the  evaluation  was 
with  a  calibration  analyzer  (Timcter.  RT200)    Two  hand  method  of  ventilation  was  used  to  perform 
U  a  constant  frequency  (f)of  20  b/min    Results:   FD02  measurements  varied  with  reservoir  types 
ion  in  FD02  were  dependent  on  tidal  volume  (VT)  and  minute  ventilation  (VfJ  capabilities  of  each 
(Table  I)  Conclusion:   This  study  evaluated  MRBs  to  replace  our  current  nondisposable  and 


uidelin 


.  Ino 


i.  Respiratory  Care  Practitioners  (RCP) 


High  FD02  and  VE  requ 


lhcFTX)2    Vane 

beneficial  feature  thai  allows  tl 
mg  (LBT)  do  not  fac 


and  assessing  adult  manual  resuscitation 
: i talon  at  a/of  20  h/min    Reservoir  types 
highFD02    We  feel  the  poly  bag  (PB) 
isess  adequate  02  flow    Accumulators 


MRB 

Reservoir 

FD02 

V.Ltai. 

Gibcck 

PB 

65 

25  1  ±  1  3 

PB 

24  6  ±0.7 

72 

244*2 .1 

PB 

21  6*  15 

PB 

213*  [J 

Pulmanex 

VS-VB 

PB 

48 

208*1.8 

DMR 

24  0  ±  2.6 

Interiech 

AT 

76 

204*1  8 

VL~Old 

SO 

VL-New 

AT 

71 

18  5*1 .3 

AT 

155*1  1 

LBT 

19  0*06 

VS-CB 

LBT 

84 

179*12 

Laerdal 

LBT 

75 

175*1  1 

VS-VB 

LBT 

91 

171  ±1  7 

EVALUATION  OF  THE  PULSAIR  OXYGEN  DELIVERY  SYSTEM.   Dean  Hess.  PhD. 
RRT.  Hideaki  Imanaka,  MD.  Robert  M  Kacmarek.  PhD.  RRT    Respiratory  Care  and 
Anesthesia.  Massachusetts  General  Hospital  and  Harvard  Medical  School.  Boslon,  MA 
Pulse-dose  systems  sense  a  pressure  drop  in  the  cannula  and  deliver  a  pulsed  dose  of  O.    We 
evaluated  the  Pulsair  OMS  50  pulse-dose  O.  delivery  system  (DeVilbiss.  Somerset  PA)  relative 
to  trigger  pressure  (PTR).  trigger  delay  (To),  pulse  volume  delivery  (vol),  peak  flow  delivery 
(VPK),  time  of  active  flow  from  the  Pulsair  (Tact),  and  total  time  of  flow  from  the  cannula 
(TTOT) .   Methods:  O.  pressure  into  the  Pulsair  was  controlled  to  35  or  50  psi  with  a  regulator 
An  02  cannula  with  7  ft  of  tubing  was  used  (Baxter.  Valeenia  CAl  and  additional  tubing  (Baxter. 
Valcenia  CA)  was  connected  to  extend  the  length  to  35  ft     The  cannula  prongs  were  connected 
via  a  Y-ptece  to  a  screen  pneumotachometer  (Hans  Rudolf.  Kansas  City  MO)  that  was  calibrated 
at  0  and  0  25  L/s  (Brooks,  Hatfield  PA).   Pressure  (±2  cm  H,0,  Validyne,  Northridge  CA)  was 
measured  immediately  proximal  to  (he  pneumolaihomeler    Pressure  and  flow  signals  were 
digitized  (CODAS)  at  1000  Hz    Flow  leaving  the  cannula  was  integrated  to  volume    PTR  was 
determined  by  slowly  decreasing  pressure  distal  to  the  pneumotachometer  until  the  Pulsair 
responded  TD  was  determined  n\  producing  .i  large  step  change  in  pressure  and  measuring  the 
time  between  Ptr  and  Pulsair  response    Tact  was  measured  as  ihe  interval  from  the  beginning 
of  flow  lo  VPK.  TTOT  was  measured  as  the  entire  time  interval  of  flow  from  the  cannula,  and  AT 
was  the  difference  between  Tact  and  TTOT    Flow  settings  of  1 ,  2,  3,  and  4  were  evaluated 
Statistical  analysis  consisted  of  mean  ±  SD  (n=5)  and  ANOVA    Results: 


n,m 

<l.  p .   - 11 

W  psi.  55  ft 

"psi    7f, 

V  psi.  V<  li 

TD 

..I 

ar 

TD 

vol 

AT 

TD 

vol 

4T 

TD 

Vol 

41 

1 

54  2d 

ID4 

).099i 

0009 

sj  6* 

006* 

0  227i 

37  6± 
2  7 

'mis' 

1  I19H 
0  007 

121  6± 

1  1  4- 
003 

1    |90: 

1.003 

2 

M  2d 

34  0* 

id; 

).095d 

: 

126  Ot 

n!,! 

on"' 

36  81 

oo?' 

j!om 

1  14  2i 

26.0± 
1.06 

1225. 
1.017 

1 

M  2d 

•JI4- 

1.03 

O093* 
0  001 

118.0* 

0  05 

0  287. 

kfe 

18  21 

ions 

2  6  61 

18  4 
12 

122  b 
K1I12 

A 

SI  2d 

.','.' 1 

0  094* 

I27  0i 
14 

0,06 

0  279i 
(1  001 

40  2i 

ajL 

Sill,' 

1,05 

0  1  1  Si 

0,001 

116  6. 

SO  7d 

'.0 1 

1227- 

!.W: 

Mean  PTR  for  all  settings  was  0  09  ±  0  01  cm  H,0    TACT  was  0  1  ±  0.003  s,  0.2  *  0.003  s.  0  3  ± 
0.002  s.  and  0  4  t  0.002  s  for  settings  of  1 ,  2.  3.  and  4.  respectively    O-  volume  was  affected  by 
the  driving  pressure  <P*0  001)  and  flow  setting  (P-0  001 ).  but  was  not  affecled  by  tubing  length 
(P  0  6X5)     Vpk  was  lower  with  longer  tubing  length  and  lower  driving  pressure  (P  <  0.001  in 
each  case)    Differences  between  Ttot  were  significant  for  tubing  lenglh  (P-  0  001 )  and  driving 
pressure  (P<0.00l)    Conclusions:   Ptr  of  (he  Pulsair  was  very  low  (-0.1  cm  H,0).  Tu  was 
affected  by  driving  pressure  and  tubing  length  and  the  magnitude  ot  these  differences  may  be 
clinically  important    Tl)  differences  arc  probably  due  to  (he  effects  of  driving  pressure  and 
tubing  length  on  the  time  constanl  of  Ihe  system    Trt  >l  was  greater  than  1  At  I  due  to 
decompression  of  Oj  from  the  tubing,  and  compression  and  decompression  ol  ().  in  the  tubing 
explains  why  the  O]  volume  delivered  was  not  affecled  b>  tubing  length    It  is  important  for 
homccarc  providers  to  appreciate  the  effects  of  tubing  length  and  driving  pressure  on  the 
performance  of  these  devices  (Supported  in  part  by  DeVilbiss) 

OF-95-098 


AN  EVALUATION  OF  02  BLEED  RATES  WITH  THREE  DIFFERENT  BRANDS  OF 
BLENDERS   Julie  Ballard  BS.  RRT  and  John  Salyer  BS,  RRT.  Primary 
Children's  Medical  Cenler.  Saft  Lake  Cily,  Uiah.    Introduction:   We  sought  to 
determine  the  amount  of  02  that  is  wasled  due  to  bleed  by  three  brands  of 
blenders.    Methods:  We  tested  10  Sechnst  Air-Oxygen  Mixers  Model  3500 
HL,  11  Bird  Low  Flow  Microblenders  Model  3920,  and  3  Bio-Med  Low  Flow 
Air/Oxygen  Blenders  Model  2003.    We  aflached  the  blenders  to  a  piped  in 
source  of  air,  and  an  E-cylinder  ol  02  via  the  same  preset  two-stage 
regulator(Venflow).  Each  run  consisted  of  attaching  the  blender  to  the  gas 
sources,  leaving  all  flow  meters  turned  off,  checking  all  fittings  for  leaks  using 
a  sudsy  solution,  and  recording  the  psi  in  Ihe  E-cylinder.  The  system  was  then 
left  altached  to  ihe  gas  sources  for  =  1  hour,  at  the  end  ot  which  the  psi  and  the 
lime  elapsed  were  recorded.   Two  of  the  blenders  were  equipped  with  detachable 
auxiliary  flow  meters  for  flow  rates  <  3  L/m.    These  were  tested  wiih  and 
without  the  flow  meters  attached   We  then  compuied  flow  per  minute  for  each 
blender  according  to  this  formula:  (psi  x  0  28)/elapsed  time  in  minutes  = 
liters  of  02  bleed  per  minute   where  psi  was  the  pressure  difference  in  the  E- 
cylinder  between  the  start  and  finish  of  each  run.  Results  for  each  blender  type 
were  then  averaged  and  tested  for  statistical  significance  using  ANOVA  factorial 
with  significance  set  at  P<0  05.  Results:    We  found  statistically  significant 
and  financially  important  differences  between  ihe  amount  of  02  wasted  by  Ihe 
different  blenders.    Results  are  in  the  figure  below 


i  Sechrist 
*  Bird  NAF 
j  Bird  AF  ■ 

j  Bio  Med  NAF  ■ 
i    Bio  Med  AF 


AF  =  auxiliary  flowmeter  attached 
NAF  =  no  auxiliary  flowmeler  attached 


ANOVA  P<0  0001 


-10         123         4         56         78 

Mean  Rate  of  02  Bleed  Lm 
Error  Bars:  ±  2  SD 
Discussion      The  table  below  lists  the  potential  costs  per  blender  per  day 
assuming  our  cost  of  02  at  $.533/100  It3  and  283  L'100  ft3 
Daily  Cosl         Yearly  Cost 


S.vh 


Bird  AF 


$1  .71 


f   .,1 


$624.15 


$222  65 


Clearly,  leaving  blenders  plugged  in  continuously  with  auxiliary  flow  meters 
attached  contributes  significanily  to  costs,  In  our  35  bed  NICU  where  Sechrist 
blenders  are  used.  Ihis  amounts  to  -  $21,845  per  year. 


1192 


RESPIRATORY  CAR!."  •  NOVHMHHR  '95  VOL  40  No  I  I 


Monday,  December  4,  3:00-4:55  pm  (Rooms  230A-B) 


rHE  EFFECTS  OF  VARYING  SET  HUMIDIFIER  TEMPERATURE  AND  VENTILATOR 
FLOW  RATE  ON  THE  RELATIVE  HUMIDITY  DELIVERED  BY  THE  ANAMED 
UlTvnnrnmFHFlTFnHIIMinrFTFR  SYSTFM  RusiellT  Rnd  RRT  Mart  Goldstein. 
U£I.  Mercy  San  Juan  Medical  Center.  Carmichael.  California, 
"here  is  little  data  available  regarding  the  humidity  output  of  modem  humidifiers  This  study 

xamined  the  effect  of  varying  ventilator  flow  rate  and  set  humidifier  temperature  on  the  relative 
lumidity  delivered  by  the  Anamed  Humiditube  (Las  Vegas.  Nevada)  heated  humidificauon 
ystem.  This  system  is  of  a  non-tradiuonal  design  incorporaung  a  heated  wick  that  runs  the 
.ntire  length  of  the  inspiratory  tubing.  Methods:  The  Anamed  Humiditube  heated  humidifcalion 
ystem  consisting  of  heater  controller,  pump  and  heated  inspiratory  wick  was  attached  to  a 
-tamilton  Veolar  (Reno.  Nevada)  mechanical  ventilator.  The  mcrhanical  ventilator  was  placed 
n  the  volume  control  mode  with  a  square  inspiratory  flow  wave  form.  A  healed  humidity 

hamber  (HC) .  37.2  C°  (±  1.8  C°).  was  constructed  to  accommodate  the  probe  of  a  capacitance 
ype  digital  hygrometer  (Curun-Matheson  Scientific.  Brisbane.  CA,  Model  #  244-355). 
nsptratory  gas  passed  through  the  HC  for  relauve  humidity  measurement.  A  thermocouple 
nermomeler  (Baxter  Inc.  Duo  Temp)  conunuously  displayed  the  temperature  adjacent  to  the 
\named  humidifier  temperature  probe  on  the  inspiratory  side  of  the  patient  wye.  Stabilized, 
■epeat  measures  were  collected  at  1  minute  intervals  until  10  measurements  at  each  variation  of 
emperature  and  set  ventilator  flow  rale  were  complete.  Prior  to  testing  all  equipment  was 
alibrated  to  the  manufacturer's  specifications  Results:  Data  was  analyzed  using  Analysis  of 
Variance  (ANOVA).  Statisucal  significance  existed  within  and  between  all  groups 

<  0.0001. 

Set 

Temperature 

(C°) 

Ventilator 
Flowrale 

(L/min) 

Hygrometer 
Temperature 
(C°  ±SD) 

Relative 
Humidity 

1';  ±SDi 

Absolute  Humidity 
(mg  H2O/L  ±SD) 

32 

40 

3 193  (±0  051 

96.48  (±  0  62J 

32  60  (±0.20) 

34 

40 

33.60  (±0.07) 

98.84  (±  0.42) 

36.48  (±0.15) 

36 

40 

35.58  (±0.19) 

94.46  (±1  52) 

.1861  (±0.59) 

38 

40 

36.72  (±0.62l 

86  74(±(lh6i 

37,53  (±0.25) 

32 

60 

31. 79  (±0.02i 

95.52.  (±0.34) 

31  80  (±0.11) 

34 

60 

33.34  (±0.05) 

98.85  (±023) 

35.95  (±0  08) 

36 

60 

3-4.92  (±0.151 

93.29  (±0.76) 

36.77  (±0  28) 

IS 

60 

36.04  (±0.07) 

86  32  (±0.051. 

36  06i±(l  IK: 

32 

80 

31.57  (±0.03) 

96  11  (±0  42) 

31  76<±0  13) 

34 

80 

33.10  (±0.051 

98.92  (±0.32) 

35  45  (±0.11) 

36 

80 

34  57  (±0.101 

91.11  (±0.52) 

35.39  (±0.18) 

38 

80 

35.75  (±0.03) 

86  51  (±0  27) 

35  S6  111  18) 

32 

100 

31.44  (±0.03) 

9621  (±0.18) 

31  57  (±0.061 

34 

100 

32  98  (±0  08) 

98  57  (±0.22) 

35  07  (±0  08) 

36 

100 

34  50  (±0.06) 

91  11  (±049) 

35  39  (±0.17) 

38 

100 

3559  (±0.03) 

8753(±021) 

15  77 («](«) 

( 

"onclusion:  The  Anamed  Humiditube  met  the  American  National  SuuiJards  Insuiute  (ANSI) 
eated  humidifier  output  standard  of  30  mg  H2O/L  under  all  lest  conditions. 

OF-95-1 

59 

THE  EFFECTS  OF  V ARYfNG  SET  HUMIDIFIER  TEMPERATURE  AND  VENTILATOR 
FLOW  RATE  ON  THE  RELATIVE  HUMIDITY  DELIVERED  BY  THE  FISCHER  & 
PAYKF.l.  MR-730  HEATED  HUMIDIFIER.  Russell  T.  Reid.  RRT  Mark  Goldstein.  RRT. 
Mercy  San  Juan  Medical  Center.  Carmichael,  California. 

This  study  examined  the  effect  of  varying  ventilator  0ow  rate  and  set  humidifier  temperature  on 
the  relauve  humidity  delivered  by  the  Fischer  &.  Paykel  (F&P)  MR-730  heated  humidificauon 
system.  Methods:  An  F&P  MR-730  healed  humidifier  (Auckland,  New  Zealand)  equipped  with 
a  model  #290  high  flow  humidificauon  chamber  and  72"  dual  heated  wire  cucuil  (Hudson  RC1 
Model  780-32.  Temecula,  CA)  was  attached  to  a  Hamilton  Veolar  (Reno.  Nevada)  mechanical 
ventilator.  The  mechanical  ventilator  was  placed  in  ihe  volume  control  mode  with  a  square 
inspiratory  flow  wave  form.  A  healed  humidity  chamber  (HC) .  37.3  C°  (±  1.8  C°),  was 
constructed  to  accommodate  the  probe  of  a  capacitance  type  digital  hygrometer  (Curtin- 
Matheson  Scientific.  Brisbane.  CA.  Model  #  244-355).  lnspualory  gas  passed  through  the  HC 
for  relative  humidity  measurement.  The  heated  wire  controller  was  set  for  0  C°  lemeprature 
differential  between  the  humidifier  chamber  and  the  proximal  airway.  A  thermocouple 
thermometer  (Baxter  Inc.  Duo  Temp)  continuously  displayed  temperature  from  two  areas  within 
the  venulalor  circuit  1)  adjacent  to  the  F&P  MR-730  humidifier  chamber  temperature  probe  and; 
2)  adjacent  to  the  humidifier  temperature  probe  on  the  inspiratory  side  of  the  patient  wye. 
Stabilized,  repeat  measures  were  collected  at  1  minute  intervals  unul  10  measurements  at  each 
variation  of  temperature  and  set  ventilator  flow  rale  were  complete.  Prior  to  testing  all 
equipment  was  calibrated  to  the  manufacturer's  specificauons.  Results:  Data  was  analyzed  using 
Analysis  of  Variance  (ANOVA).  Statisucal  significance  existed  wilhin  and  between  all  groups 
p<  0.0001. 

Set 

Temperature 
(CI 

Venulalor 
Flowrale 
(L/min) 

Hygrometer 
Temperature 
(C°  ±SD) 

Relauve 
Humidity 
(%  ±SD) 

Absolute  Humidity 
(mg  H2O1L  ±SD) 

32 

40 

31.41  (±0  08) 

99  36l±0  76) 

32.60  (±0.25) 

34 

40 

32  16  (±0  57) 

97.15  (±2  101 

33  42  (±0.71) 

36 

40 

34  87  (±047) 

94  21  111  72) 

37  14   (±0.64) 

3K 

40 

36.23  (±0.28) 

97  08  (±0  941 

41  12  (-11  39) 

32 

60 

31.30  (±0  22i 

99.07  (±0.72) 

32.27  (±0.23) 

34 

60 

32.W  (±0  15i 

100.0  (±0.00) 

35.58  (±0.00) 

36 

60 

34  52  (±0.08) 

95.38  (±0.80) 

36.77  (±0  29) 

38 

60 

38.43  (±0.07) 

100.0  (±0.0) 

47  45  (±0.00) 

32 

80 

31  24  (±0  05) 

99.83  (±0  19) 

32.51  (±0.06) 

34 

80 

32.73  (±0.12) 

99.68  (±0  30) 

35.21  (±0.11) 

36 

80 

34.51  (±0  23) 

96.74  (±0.75) 

37.57  (±0.28) 

38 

80 

3751  (±0.68) 

100  (±0.0) 

45  16  (±0.00) 

32 

K.I 

31  18  (±0  30) 

99.46  (±0.52) 

32  16  (±0.17) 

34 

100 

32.82  (±0.54) 

](K)0l±<).0) 

35  32  (±0  00) 

36 

100 

35.02  (±1.26) 

95  89  i:0  75) 

38  07  (±0.29) 

38 

100 

36.31  (±0  09) 

99  28(10  60) 

42.06  (±0.25) 

Conclusion:  The  F&P  MR-730  mel  the  American  National  Standards  Institute  (ANSI)  healed 
humidifier  output  standard  of  30  mg  H2O/L  under  ail  test  conditions. 

OF-95-160 

FEASIBILITY  OF  RECYCLING  PEDIATRIC  BICORE  FLOW  SENSORS.  Jim  Keenan 
BS.  RRT.  Julie  Ballard  BS,  RRT.  John  Salyer  BS.  RRT.  Primary  Children's 
Medical  Cenler.  Sail  Lake  Cily.  Ulah.  Introduction:  The  Bicore  CP-100 
bedside  neonatal  pulmonary  function  monitor  uses  a  variable  orifice 
pneumotachograph  sensor  that  is  labeled  as  "single  patient  use".  We  sought  to 
test  the  the  feasibility  of  recycling  these  items.  Methods:  We  used  the 
unpublished  Bicore  recomended  field  verfication  test  procedure  which 
includes;  (1)  the  sensor  attached  to  a  Hans-Rudolph  volumetric  calibration 
syringe  set  at  60  mL.  (2)  a  3.0  ETT  was  attached  to  the  other  end  ol  the 
sensor  10  simulate  clinically  encountered  resistance.  Alter  sell  calibration, 
10  excursions  ol  the  syringe  plunger  were  performed.    Inspiratory  and 
expiratory  tidal  volumes  are  then  noted.  An  acceptable  range  of  readings  was 
developed  using  the  manufacturers  reported  inaccuracy  ol  7  %  above  and 
below  the  actual  volume  ol  60  mL  (55.8-64.2  mL).  II  a  sensor  had  either 
inspiratory  or  expiratory  volumes  outside  the  acceptable  range,  it  failed  the 
test  and  was  disposed  ol.  Sensors  were  tested  new,  and  after  each  of  four 
cleanings.  In  between  which  sensors  were  used  In  the  clinical  environment. 
After  each  cleaning  they  were  marked,  and  clinicians  were  Instructed  to 
return  all  sensors  lor  recycling.  II  sensors  were  visibly  soiled  or  damaged, 
they  were  discarded.  Cleanings  consisted  ol  immersion  in  a  deproteinizing 
agent  {Klenzyme,  Merck  Co.  Inc.)  tor  -  5  minutes,  followed  by  cold  liquid 
sterilization  in  an  activated  gluteradehyde  solution,  followed  by  thorough 
rinsing  with  water.  Sensors  were  dryed  by  being  attached  to  an  air  flowmeter 
set  at  3-5  L/m  until  dry.    Results:  The  table  below  lists  our  results. 

Passed Failed 

Sensors 

New 

After!  st  Cleaning 

After  2nd  Cleaning 

After  3rd  Cleaning 

Atler  4th  Cleaning 

Discussion:  We  found  it  disturbing  that  6%  of  new  sensors  failed  the 
manufacturer's  recommended  verification  procedure.  New  sensors  cost  -  $28 
each  and  thus   a  recycling  program  could  potentially  result  in  considerable 
cost  savings.  It  appears  that  more  than  three  cleanings  yields  little  benefit. 
although  the  low  number  (50%)  of  sensors  slid  in  the  study  after  three 
cleanings  may  bias  this  finding.  It  is  possible  that  some  sensors  were  not 
returned  from  clinical  practice  for  recycling  because  they  failed  while  on 
patients  secondary  lo  being  recycled  and  where  discarded  by  practitioners  at 
the  bedside,  although  we  received  no  anecdotal  reports  of  this  during  the 
study.  Conclusion:  A  program  to  recycle  these  sensors  appears  feasible.   A 
6%  failure  rate  of  new  sensors  seems  unacceptably  high. 

OF-95-211 


# 

% 

#                 % 

33 

94% 

2 

6% 

1  7 

6  8% 

8 

32% 

1  3 

7  6% 

4 

24% 

9 

69% 

4 

31% 

0 

0% 

4 

100% 

ACCURACY   OF   NEONATAL  TIDAL   VOLUME 
MEASUREMENT     DEVICES 

Dennis  Ring.  RRT  ,  Mark  Mammel.  MD,  Infant  Diagnostic  and 
Research  Center,  Children's  Healthcare,  St.  Paul,  MN 

Introduction:   Measurement  of  Vt  in  newborn  infants  and  small 
children  has  recently  become  available  for  use  at  the  bedside  in 
the  NICU.  The  purpose  of  this  study  was  to  test  7  flow/  volume 
measurement  systems  commercially  available  for  neonatal  use  for 
accuracy  in  reported  Vt  values.  Methods:  We  tested  these 
systems:  Bear  NVM-1,  BICORE  CP-100,  Bird  Partner  Hi,  Drager 
Babylog  Ventilator,  Novametrix  VenTrak  (disposable  sensor), 
PeDS  and  SensorMedics  2600.  We  calibrated  each  system 
according  to  manufacturer's  instructions  immediately  prior  to 
testing.  We  tested  each  device  using  calibration  syringes  (Hans 
Rudolph,  #5510,  and  #5520)  at  six  known  Vj  values:  4,  6,10, 
20,40,  and  60  mLs.,  hand  cycling  the  calibration  syringe  at  two 
"breathing  rates",  30  and  60  per  minute.  We  collected  three  test 
values  at  each  Vt  and  rate  combination  and  report  the  mean  as 
compared  to  the  known  test  standard.  All  values  are  normalized  to 
BTPS.  Results:  Data  were  evaluated  for  accuracy  in  Vt 
measurement  as  mean  variances  from  test  standard  in  mLs.,  and 
in  per  cent: 


mean   variance, 
mLs. 

mean   variance, 
% 

Bear    NVM-1 

-0.76±1.00 

-1.1±4.5 

BICORE    CP-100 

+  2.3514.53 

+13.5±9.3 

Bird  Partner  Hi 

-0.03±0.39 

-1.7±3.2 

Drager    Babylog 

-0.23±.54 

+0.01±3.4 

Novametrix    VenTrak 

+  0.91±0.9 

+5.1±2.4 

PeDS 

-1.41+2.47 

-0.2±8.8 

SensorMedics    2600 

+  2.31±2.7 

+6.7±4.6 

All  devices  except  the  BICORE  CP-100  reported  Vt  accurately 
(<10%  variance).  Conclusion:  Devices  are  commercially  available 
for  accurate  measurement  of  Vt  within  Ihe  range  expected  for 
Neonatal  ICU  patients. 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1193 


Monday,  December  4,  3:00-4:55  pm  (Rooms  230A-B) 


BICORE  CP-100  ANALYSIS-VOLLME  V/S  PRESSURE  AUGMENTATION  MAX 
(PAM)  ON  THE  BEAR100U    John  Embcrgcr  BS  RRT.  Hcrben  Patrick  MD. 
Department  of  Respiratorv  Care.  Thomas  Jefferson  University  Hospital.  Philadelphia  PA 

BACKGROUND:  Since  last  year,  we  have  studied  pressure  versus  volume  (PAM.  and 
PAM  with  inspiratory  pause  (PAM&IP)  versus  A/C  with  decelerating  flow]  using 
BearlOOO  ventilators  (Bear  Medical  Systems -Riverside.  CA)    We  examined  if  an  airwav 
pressure  plateau  yields  a  pressure  plateau  (PP)  in  the  lungs  (thus  better  air  distribution, 
better  ox\genatiorvventilation)    METHODS:   A  computer  connected  to  a  Bicore  CP- 
100  (BICORE  Monitoring  Systems,  Irvine  CA)  (with  portex  jet  adapter  instead  of  an 
esophageal  balloon)  collected  waveform  data  on  PAM  study  patients    RESULTS: 


I )  The  flow  of  PAM  is  higher  than  AC.  and  more  aggressive  (flow  nses  quicker  at 
inspiration)    2)  AC  tracheal  pressure  (TP>  nses  linearly  to  the  tracheal  peak  inspiratory 
pressure  (TPrP).  but  PAM  TP  decelerates  as  it  approaches  TPIP    3)  AC  airway  peak 
inspiratory  pressure  (APIP)  is  higher  than  PAM  APIP,  but  PAM  TPIP  is  higher  than  AC 
TPIP    4)'  No  TP  waves  reach  PP  even  when  airway  pressure  (AP)  wave  has  a  long  PP 
5)     On  exhalation,  AP  reverts  quickly  back  to  baseline  but  TP  slowly  drops  back  to 
baseline    CONCLUSIONS:    1)  PAM's  higher  initial  flow  meets  the  demands  of  a 
critically  ill  air  hungry  patient    2)  AC  forces  pressure  quickly  into  the  lungs  (linear  TP 
nse)  even  when  the  lungs  are  near  maximal  stretch  With  PAM,  TP  rise  decelerates 
during  maximal  lung  stretch  (end  of  inspiration)  thus  PAM  has  a  decreased  shear  force 
3)  PAM  pressure  more  effectively  crosses  the  endotracheal  tube  than  AC    4)  Despite  a 
long  AP  plateau.  airwa\  to  alveolus  is  not  statically  equilibrated    5)  Frequent 
AutoPEEP  checks  are  important  when  lengthening  the  inspiratory  time  (PAM&IP) 


SIEMENS    SERVO    300    PERFORMANCE    ANALYSIS 

Thomas  D.  EasLPh.D..  Fidel  Silva,  MD.  Jeff  Anderson,  MS 
Pulmonary  Division.  LDS  Hospital,  8th  Ave  and  C  St.  Salt  Lake  City.  UT  84143 
Introduction:  The  purpose  of  this  research  was  to  develop  the  automated  tesung  tools  and 
techniques  to  thoroughly  evaluate  the  performance  of  the  Siemens  Servo  300  ventilator  under  a 
variety  of  different  conditions.  The  specific  aims  were:  1.  Construct  an  accurate  single 
compartment  adult,  pediatric  and  neonatal  test  lung  that  was  interfaced  id  a  computer  for  data 
collection.  2.  Develop  a  set  of  tests  and  failure  condiuons  which  would  adequately  challenge  the 
ventilator  3.  Test  die  ventilator  under  a  comprehensive  set  of  condiuons. 
Methods:  The  adult  and  pediatric  test  lung  used  a  Michigan  Instruments  TTL  test  lung  that  was 
modified  to  measure  volume  wiih  1%  accuracy  using  a  linear  variable  displacement  transducer 
(LVDT)  to  record  bellows  displacement.  The  pressure  transducers  at  the  mouth  (proximal)  and  in 
the  test  lung  (distal)  were  Sensym  (±1  psi)  solid  state  pressure  transducers.  Fi02  was  measured 
using  a  Ventronics  Oxygen  Fuel  Cell  Electrode.  Data  was  collected  using  a  National 
Instruments  analog/digital  converter  in  a  Macintosh  computer.  The  neonatal  test  lung  was 
constructed  using  three  fixed  volume  plexiglas  cylinders  that  were  packed  with  copper  wool  to 
provide  isothermal  behavior.  The  cylinders  were  designed  to  provide  0.47.  0.88  and  1.20  mfcm 
H20  compliance.  Three  different  neonatal  endotracheal  lubes  (2.0.  2.5  and  3.0  mm  ID)  were 
connected  to  the  test  cylinder.  A  spring  loaded  pneumatically  driven  syringe  was  used  to  trigger 
the  neonatal  test  lungs.  The  cylinders  were  calibrated  and  volume  accuracy  was  <  1%. 

There  are  three  different  patient  sizes  and  1 1  different  mode  and  triggering  combinauons 
on  the  Servo  300  (33  different  permutations).  Each  pcrmutauon  was  tested  at  three  different 
levels  of  ventilatory  support;  low,  medium  and  high  (99  tests).  27  different  condiuons  were 
developed  that  simulated  normal  conditions  as  well  as  leaks,  electrical  and  pneumaUc  failures,  and 
other  common  clinical  conditions  known  to  cause  vcnulator  failure  (i.e.  bovie  use).  Each 
condition  was  tested  with  all  99  tests  unless  the  ventilator  was  non-functional.  60  seconds  of 
data  was  collected  for  each  test,  convened  to  STPD  and  stored  in  a  database  for  analysis. 
Results:  709  tests  were  made  under  27  different  conditions.  58  comparisons  were  made  per 
lest  (41,122  test  results).  The  ventilator  performed  very  well,  even  with  the  toughest  of 
challenges.  Over  all  test  conditions  the  average  accuracy  of  all  the  different  variables  was  0.87% 
and  the  precision  was  28%.  This  represents  a  global  worst  case  performance  as  it  includes  many 
different  failure  modes  in  which  the  ventilator  could  not  deliver  the  set  values.  With  normal 
conditions  the  average  accuracy  was  1.19%  and  the  precision  was  14,6%.  The  control  of  the 
inspired  tidal  volume  was  exceptionally  accurate  with  an  accuracy  of  -0.37%  over  all  condiuons, 
patient  sizes,  ventilatory  support  conditions  and  modes.  Fi02  control  was  accurate  (0.06% 
Fi02)  and  precise  (6  %  Fi02).  The  pressure  control  level  was  1 4  ±3  cm  H20  below  the  setting. 
Pressure  support  level  was  0.4  ±4  cm  H20  below  the  setting.  PEEP  was  less  than  setung 
(difference  -0.56±  1 .6  cm  H20);  however,  in  adults  it  was  larger  (-2±2  cm  H20).  Mean  airway 
pressure  measured  by  the  Servo  300  was  low  (-0.911.37  cm  H20,  -12119%).  Errors  in  pressure 
were  smaller  with  decreasing  patient  size.  Ventilatory  support  level  had  little  impact  on  errors. 
Bovie  use  near  die  ventilator  did  interfere  with  monitoring  and  the  digital  interface. 
Conclusions:   The  Servo  300  performed  very  well  even  when  faced  with  common  clinical 
situations  that  have  been  known  to  produce  faults  in  mechanical  ventilators.  The  small 
difference  between  the  pressure  settings  and  measured  values  are  likely  due  to  knob  calibration 
errors  and  are  not  clinically  significant.  It  is  difficult  to  compare  results  to  other  ventilators  as 
there  are  no  published  data  for  performance  over  a  wide  range  of  venualtory  support  and  failure 
conditions. 
Acknowledgments:  Siemens  Life  Support  Systems,  Solna,  Sweden. 

OF-95-184 


VI 


Estimated  PaCOG  and  V/Q 


INTELLIGENT  C02  MONITORING 

Jigish  P.  Tnvedi  M.S..  George  Thomsen  M.D.,  Jeff  Anderson  M.E.,  Thomas  D.  East  Ph.D. 
Pulmonary  Division.  LDS  Hospital  and  the  University  Of  Utah,  Salt  Lake  City.  Utah  84143 
Introduction  :  Reliable  non-invasive  methods  to  determine  PaC02  are  not  presendy 
available.  End-tidal  partial  pressure  of  C02(PetC02)  is  only  useful  as  monitor  PaC02  in 
patients  with  little  gas  exchange  derangement.  The  difference  between  PctC02  and  PaC02 
may  be  quite  large  and  trends  can  be  misleading.  The  purpose  of  this  work  was  to  create  a 
dependable  non-invasive  monitor  of  PaC02  for  use  with  mechanical  ventilation. 
Methods  :A  Macintosh  llci  computer  was  used  to  measure  the  airway  pressure,  gas  flow 

I ' 1      |&  rr-rz 1  and  expiratory  timing  signals  from  a 

|Venttlalor  f^fjW-^r         ,    I  Siemens  900C  ventilator,  and  the  partial 

'      I  w\         IftnalYZen  pressure  of  expired  C02  from  a 

Novametrix  C02  monitor.  These 
variables  were  sampled  at  100  Hz. 
PetC02.  the  slope  of  phase  III  of  the 
capnogram.  VC02.  udal  volume,  and 
vcnulatory  rate  were  calculated  on  a 
breath  -by-breath  basis  and  used  as  input 
parameters  to  a  mathematical  model  of 
C02  uptake,  distribution  and  eliminaUon.  With  each  breath,  the  model  predicted  values  for  all 
of  the  input  parameters  were  compared  to  actual  values  and  the  differences  (errors)  used  in  a 
Bayesian  modified  Chi-Squared  parameter  estimation  to  predict  what  die  values  should  be  for 
PaC02  for  each  lung  compartment.  Essentially  this  system  provided  a  non-invasive  esumatc 
of  PaC02  for  each  of  the  two  compartments.  The  accuracy  and  precision  of  the  data 
acquisiuon  system  and  calculated  parameters  was  tested  by  using  precision  C02  flows  (Tylan 
Flow  Controllers)  into  a  mechanical  lung  model  (Michigan  Instruments).  To  test  the 
feasibility  of  the  concept .  we  collected  at  least  two  hours  of  data,  from  five  patients  with  the 
Adult  Respiratory  Distress  Syndrome.  PaC02  values  from  arterial  hlood  gases  were  compared 
with  estimated  PaC02  values  predicted  by  our  system.  Results  :  The  laboratory  testing  of 
the  data  collection  and  analysis  software  showed  accuracy  of  0.4%  and  precision  of  0.6%  in 
measurement  of  VC02.  Four  patients  had  relauvcly  stable  PaC02  during  the  data  collection 
period.  The  system  was  able  to  very  accurately  predict  PaC02  under  these  circumstances  (error 
less  than  5%).  One  paucnt  had  a  long  record  of  fluctuating  PaC02  which  was  adequate  to 
challenge  the  feasibility  of  the  system.  In  this  patient,  14  ABG  samples  were  collected  during 
48  hours.  For  ABG  samples  obtained  during  controlled  mechanical  ventilation,  the  error 
between  measured  and  predicted  PaC02  was  1  9  i  2  2  mmHg  (mean  ±  SD).  For  ABG  samples 
obtained  during  assisted  vcnulalion  the  error  was  -6.8  ±  17,8  mm  Hg  .  Conclusion  :  A 
computerized  system  designed  provide  non-invasive  estimates  of  PaC02  in  a  two 
compartment  model  was  developed  and  the  system  was  shown  to  be  accurate  and  precise  in  a 
carefully  controlled  laboratory  setting    A  small  clinical  feasibility  study  indicates  that  die 
system  can  accurately  predict  PaC02.  however,  accuracy  is  influenced  by  noise  in  measurement 
of  C02and  flow,  This  effect  is  more  pronounced  in  patients  who  arc  assisting.  In  the  future, 
digital  signal  processing  techniques  must  be  used  to  extract  representative  values  from  the 
"clinically  noisy"  environment  prior  to  making  estimates  of  PuC02.  Wiih  such 
improvements  this  system  should  be  capable  of  providing  robtitl  non-invasive  predictions  of 
PaC02. 

Acknowledgment:  Wc  sincerely  thank  Siemens  Life  Support  Systems,  Solna,  Sweden  and 
Dcscret  Foundation,  Salt  Lake  City.  UT  for  their  support. 

OF-95-185 


SERVO    LUNG    SIMULATOR 

Jigish  P.  Trjvedj  M.S..  Jeff  Anderson  M.E..  Mark  Hoyi*. 

Sandy  Metcalf,  RRT,  Pat  McEwen,  RRT.  Thomas  D.  East  Ph.D. 

Pulmonary  and  Respiratory  Care  Divisions.  LDS  Hospital  and  The  University  Of  Utah.  Salt 

Lake  City.  Utah  84143       *MH  Custom  Design,  Salt  Lake  City,  UT  84047 

Introduction  :  Existing  lung  simulators  do  not  provide  accurate  measurement  of  volume  and 

flow,  a  wide  variety  of  resistance  and  compliance  values,  or  adequate  simulation  of  spontaneous 

breathing  and  triggering  events.  The  purpose  of  this  project  was  to  design,  construct  and  test  an 

accurate  and  flexible  two  compartment  lung  simulator  that  would  provide  a  realistic  simulation  of 


spontaneous  breathing  and  triggering  events 
Methods:  Our  engineering  design  goals  wen 

2  compartment  lung  model  including  trachea 

Tidal  Volume:  50  -  4000  ml 

Airway  Pressure:  -50  -  + 1 50  cm  H20 

Simulation  of  Pressure  or  Row  Triggering 

Resistance:  5-1000  cm  H20/l/s. 

To  accomplish  these  goals  we  constructed  a  computer  controlled  high  speed 
a  piston  (Figure  1)  as  necessary  for  the  overall  system  to  behave 


;  follows: 

Flow  Rate:  0  -  180  l/min 
Respiratory  Rale:  0-150  Breaths/min 
Compliance:  1-500  ml/cm  H20 
Simulation  of  Spontaneous  Breathing 
Accuracy  <1% 

which  r 


Servo  Lung  Simulate! 


compartment  lung  with  an  active  chest  wall. 
Pressure  is  measured  using  a  solid  state 
transducer.  Volume  and  flow  are  measured  by  a 
precision  shaft  encoder  on  the  motor  which 
gives  a  resoluuon  of  100  pl/stcp  The  piston  is 
heated  to  accommodate  the  use  of  healed  and 
humidified  gas.  Volume,  flow  and  pressure  data 
are  collected  by  the  computer  at  400  Hz  and  a 
mathematical  model  determines  how  to  move 
the  piston  using  a  model  reference  adaptive 
controller.  The  mathematical  model  includes  pressure  or  flow  triggering  as  well  as  user  specified 
spontaneous  breathing  patterns.  Data  are  displayed  in  real-time  graphics  and  stored  lor  analysis. 
The  system  was  tested  by  lab  verification  of  the  performance  specifications.  Accuracy 
was  assessed  with  a  I  L  precision  super  syringe  (Vitalograph.  Medical  Instrumentation, 
Buckingham.  England)  and  the  Bicore  monitor  (Irvine,  CA)  during  mechanical  ventilation. 


Results  :  All  pert 


,  Figure  2  illustrates  system  performance 
for  one  particular  test  condition.  Lab  analysis 
confirmed  volume  resolution  of  100  uX/step.  This 
resolution  provides  accuracy  of  0,002-0 .01%  for  adults 
and  0.04-0.2%  for  pediatrics.  There  arc  no  commercial 
flow  or  volume  calibration  devices  dial  can  verify  this 
level  of  accuracy,  Comparison  with  the  super  synnge 
and  the  Bicore  device  yielded  differences  of  0.7510.3 1% 
and  1.411,2%  respectively.  These  differences  arc  most 
likely  due  tocnors  in  the  synnge  and  Bicore  devices. 


Conclusion  :  Wc  have  successfully  created  an  accurate,  precise  and  flexible  lung  s 
provides  a  realistic  simulation  of  spontaneous  breathing  and  triggering. 
Acknowledgment:    Siemens  Life  Support  Systems,  Solna,  Sweden 


nuljtor  that 


1194 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


Monday,  December  4,  3:00-4:55  pm  (Rooms  230A-B) 


PRESSURE  VENTILATION  DESPITE  AIR  LEAKS:  QUANTITATION  OF  LEAK 
VOLUME  AND  MAINTENANCE  OF  TARGET  PRESSURE 

Gary  Gradwcll.  BS.  RRT.  Sharon  Oliver.  CRTT,  Zenobia  Black,  CRTT.  Lila  Nash,  Shyni 
Thomas,  RRT,  Lisa  Menegaz,  CRTT,  Sharlene  Kennedy,  CRTT,  Deborah  Epley,  CRTT. 
Jerome  Taylor,  CRTT.  Herbert  Patrick,  MD,  Department  of  Respiratory  Care.  Thomas 
Jefferson  University  Hospital,  Philadelphia,  PA 

INTRODUCTION:  Although  pressure  ventilation  may  be  contraindicaled  with  air  leaks  from 
the  tracheal  caff  or  chest  tabes,  we  were  confronted  with  an  ARDS  patienl  on  pressure 
ventilation  with  an  air  leak  due  to  a  pneumothorax  and  elected  to  maintain  her  on  pressure 
control  wiih  the  Bear  1000  ventilator.  We  chose  to  bench  test  the  Bear  10OO  in  the  pressure 
control  mode  using  a  cimninfH  controlled  leak  to  determine  the  ventilator's  ability  to  maintain 
target  pressure  while  we  measured  the  accuracy  of  the  added  volume  vs.  the  leak;  we  then 
correlated  these  results  to  the  bedside  situation.  Our  hypothesis  was  that  the  Bear  1000  would 
maintain  ihe  target  pleasure  dunng  inspiration  via  flow  resulting  in  volume  compensation  for 
the  leak. 

BEAR  1000  GRAPHIC  DISPLAY:  AIR  LEAK  AT  BEDSIDE 
phase  2  (added 
volume) 

phase  3  (exp) 


phase  1        j/  |    phase  4  (leak) 

(insp.) 

VOLUME  FLOW 

METHODS:  Bench  test:  A  Bear  1000  Ventilator  set  at  P/C  of  30  cm./H20,  12  breaths/nun.  and 
a  3  second  inspiratory  time  was  connected  to  an  Oruneda  Lung  Simulate!  (resistance  =  5)  We 
measured  the  added  volume  on  inspiration  using  a  Bicore  CP-1O0  Monitor,  connected  between 
the  ventilator  wye  and  the  lung  simulator  Frve  rianlated  controlled  leaks  were  introduced  at 
the  lung  simulator  and  each  was  measured  by  a  Wallace  and  Tieman  Precision  65- 1 50 
Calibration  Flowmeter  Bedside:  We  analyzed  1 1  different  Bear  1000  graphic  displays  of  the 
patient  over  a  5  day  period  for  the  added  volume  (phase  2)  compared  to  the  leak  (phase  4), 

Bedside 


RESULTS: 

tests,  n 

leak  range,  ml 

mean  leak,  ml 

mean  added  vol,  ml 

accuracy  (leak  •  added)  /  leak)  % 

precision  (SD) 

correlation  coefficient 


Bench  lest 


150-600 


,9998 


11 
17-313 


9891 


CONCLUSIONS:  The  Bear  1000  ventilator  1)  equally  maintained  both  the  target  pressure  on 
the  bench  test  and  the  patient  by  delivering  small  bursts  of  flow  resulting  m  87%  volume 
compensation;  2)  graphic  display  accurately  quantified  the  volume  of  the  pauent's  chest  tube 
leak  as  phase  4  minus  13%. 

OF-95-206 


COMPARISON  OF  FLUTTER*  TO  POSITIVE  EXPIRATORY 
PRESSURE  (PEP)  VALVES:  A  LABORATORY  STUDY. 

lames  B.  Fink.  MS.  RRT..  Ed  Belingon,  RRT.,    Hines  VA  Hospital 
and  Loyola  Univ.  Chicago,  Snitch  School  of  Medicine,  Hines  IL,  USA 

Several  devices  have  been  recently  approved  by  the  FDA  for  use 
in  airway  clearance  with  scant  data  demonstrating  physical  effects  of 
the  devices  on  airway  and  lung  mechanics.  AARC  clinical 
guidelines  for  Positive  Airway  Pressure  differentiates  fixed  orifice 
(FO)  resistors  (PEP)  from  threshold  (TH)  resistors.  The  aim  of  this 
study  was  to  better  characterize  these  two  types  of  resistors  as  well  as 
the  new  Flutter"  valve  (Scandipharm).  We  compared  the  Flutter* 
(Scandipharm)  to  a  threshold  (Vital  Signs)  and  a  fixed  orifice 
(Mercury  Medical)  resistors,  to  determine  effects  on  airway  pressure 
patterns,  peak  expiratory  flows  (PEFR;  L/min),  peak  expiratory 
pressure  (Pexp;  cmH20),  mean  airway  pressures  (MAP;cmH20), 
work  of  breathing  (Wntjoule/L)  and  changes  in  residual  volume 
(RV;  ml  above  baseline)  during  passive  exhalation  (Vj  500  ml,  PIP 
40  L/min)  on  a  test  lung  with  compliance  of  0.02  cmH20/L.  A 
comparison  of  the  Flutter  with  TO  and  FO  resistors  (at  the  same 
relative  orifice  size)  are  shown  below: 

PEFR  Pexp  EPAP  W(pt)  MAP  RV 

FLUTTER           27.1  18.8       8.4  1.406  7.5  450 

TH  10  cmH20    39  15.5       7.5  1.255  6.6  450 

TH  15  cmH20    40  20.6  12.5  1.694  9.9  700 

FO4.0mm          23.7  9.5       0.3  0.738  0.8  0 

FO  3.0  mm          13.4  10.2       0.3  0.714  1.6  0 

FO  resulted  in  lower  PEFR,  Pexp,  W(pt)  and  RV  than  TH  or 
Flutter  (p<.001).  The  Flutter  is  similar  to  the  threshold  resistor  in 
Pexp,  EPAP,  VV(pt),  MAP  and  RV. 

We  conclude  that  the  characteristics  of  the  FO  as  a  PEP  device  are 
sufficiently  different  from  TH  and  Flutter  to  be  differentiated  from 
EPAP  (TH)  or  Flutter  when  used  in  clinical  applications  and  studies. 

OF-95-155 


EFFECT  OF  CHANGES  IN  ALTITUDE  ON  THE  OPERATIONAL  CHARACTERISTICS  OF 
THE  AMBU  TRANSCARE  PORTABLE  VENTILATOR 

Russell  T.  ReidRRT.  Rosanne  Eyler  R.N.,  UC  Davis  Medical  Center  Sacramento.  CA. 
The  use  of  portable  mechanical  venlilators  during  helicopter  transport  of  the  critically  ill  patient 
is  common  place.  However,  there  Is  little  data  available  regarding  the  performance  of  these 
ventilators  under  actual  operaling  conditions.  We  sought  to  identify  the  effect  changes  in  altitude 
had  upon  the  set  parameters  on  the  Ambu  Transcare  (Ambu,  INC.)  pneumatically  powered  and 
controlled  ventilator.  Methods:  The  Ambu  Transcare  was  connected  to  two  test  lungs  (Model 
6006832  Siemens.  Inc.).  each  with  a  capacity  of  500  mis.  wyed  together.  The  ventilator  pressure 
limiting  device  was  set  io  the  maximum  value  so  as  not  to  interfere  with  any  changes  in  delivered 
volume  or  pressure.  Baseline  ventilator  parameters  were  established  at  sea  level  (see  table). 
Ventilator  parameters  were  monitored  and  recorded,  at  2000  feel  increments,  from  sea  level 
(baseline)  10  a  maximum  altitude  of  10.000  feet.  All  measurements  were  performed  in  a  MKB- 
1 17  aeromedical  helicopter.  Sufficient  lime  was  given  between  altitude  changes  for  equipment 
stabilization  Five  (5)  repeat  measurements  were  taken  al  each  altitude.  The  following  ventilator 
parameters  were  measured:  cycles/min.  expired  tidal  volume!  VTe).  inspiratory  timet  I.  Time), 
peak  inspiratory  pressure! PIP).  I:E  ratio,  and  mean  airway  pressure! mean  PAW)  Expired  lidal 
volume  was  measured  using  a  Wright  respirometer  (Model  Mark  8,  IDE).  All  other  ventilator 
parameters  were  measured  with  an  electronic  pressure  transducer  (Pneuniogard  1230A, 
Novametrix,  Inc.)  which  was  zeroed  at  each  new  altitude.  The  Ambu  Transcare  was  powered  by 
and  delivered  100%  oxygen  to  the  test  lungs.  All  equipment  was  calibrated  according  to 
manufacturers  recommendations.  Results:  Data  was  analyzed  using  ANOV  A.  There  were 
significant  changes  in  all  parameters  at  different  altitudes  (p<0.01)  with  the  exception  of  1:E 


Parameters 

Sea  Level 
(Baseline) 

2000  Feel 

4000  Feet 

6000  Feet 

8000  Feet 

10,000 
Feel 

Cycles/min 
(mearrtSD) 

12.0(1.2) 

15.3(0.7)* 

14.3(0.4)* 

11.4(1.8)* 

11.1(0.8)* 

11.4(0.1)* 

1.  Time 

(mearrtSD 

seconds) 

1.3(0.0) 

1.0(0.1)* 

1.2(0.0)* 

1.4(0.1)* 

1 .4(0.0)* 

1.3(0.0)* 

PIPlniean 

±SDcm 

H2O) 

57.6(2.3)' 

57.0 
(13.8)* 

70.6  (2.3) 

81.4(2.1)* 

88.2(1.6)* 

91.0(0.7)* 

VTe  (mean 
±SDml) 

1000(0  01 

1030 
(27.3)* 

1050 
(0.0)* 

1234 
(47.7)* 

1360 
(20.0)* 

1444 

(5.4)* 

Mean  PAW 
(mearrtSD 
cmH20) 

12.2(0.5) 

13.9(1.2)* 

15.8(0.3)* 

15.9(1.6)* 

17.8(0.2)* 

20.4(0.1)* 

I:E  Ratio 

(meanlSDl 

1:2.8(0.0) 

1:2  8(0.1) 

1:2.6(0.0) 

1:2.8(0.1) 

1:2.9  (0.0) 

1:2.9(0.0) 

*  significant  difference  between  allitude  groups  p<0.01 

Experience:  The  authors  have  10  years  experience  utilizing  pneumatically  powered  and 
controlled  mechanical  ventilators  during  aeromedical  transport  Conclusion;  Clinically  sigmfican 
changes  in  set  parameters  may  occur  with  pneumatically  controlled  ventilators  in  un pressurized 
aircraft  cabins.  We  recommend  momtoring  mechanical  ventilator  parameters  during  flight  with 
appropriate  instrumentation.  The  Ambu  Transcare  ventilator's  calibrated  controls  became 
inaccurate  when  the  actual  barometric  pressure  differed  from  the  manufacturers  calibration 
barometric  pressure.  The  effect  of  altitude  upon  measuring  instm  mental  ion  is  unknown. 


Respiratory  Care  •  November  '95  Vol  40  No  1 


1195 


Monday.  December  4.  3:00-4:55  pm  (Rooms  230C-D) 


USE  OF  A  RELIEF  VALVE  (RV)  TO  ELIMINATE  THE  RISE  IN  PEAK  AIRWAY  PRESSURE 
SEEN  DURING  TRACHEAL  GAS  INSUFFLATION  WITH  PRESSURE-CONTROL 
VENTILATION.  Edgar  Delqado.  BS.  RRT,  Diane  Gowskl,  MD,  Adelaide  Mlro,  MD.  Leslie 
Hoffman.  PhD.  RN.  Fred  Tasota,  MS,  RN.  Michael  R  Plnsky.  MD. 
Departments  of  Respiratory  Care,  Critical  Care  Medicine,  and  Nursing.  University  of 
Pittsburgh  Medical  Center,  Pittsburgh,  PA 

The  primary  goals  of  pressure-control  ventilation  (PCV)  and  tracheal  gas  Insufflation  (TGI) 
are  to  minimize  peak  airway  pressure  (PD„H)  and  total  tidal  volume  (Vt,01)  In  an  attempt 
to  reduce  ventilator-Induced  lung  Injury  Both  techniques  have  been  utilized 
Independently  and  In  combination  In  the  clinical  application  of  TGI  with  PCV.  we 
observed  an  Increase  In  PpeaK  above  the  set  Inspiratory  pressure  (P5Bl).  This  rise  In  PDe91l 
may  lead  to  alveolar  overdlstention  and  negate  the  beneficial  effects  of  TGI  We 
reasoned  that  the  Increase  In  Ppt„,  was  due  to  the  Inability  of  the  circuit  to  relieve  the 
excess  volume  from  TGI.  We  hypothesized  that  use  of  an  In-line  RV  would  eliminate  this 
Increase  in  Pw„. 

METHODS;  A  catheter  was  Inserted  Into  the  airway  of  a  calibrated  adult  training  test  lung 
(TTL  #26001)  for  gas  Insufflation.  Auto-PEEP  was  measured  as  the  end-expiratory 
intrapulmonary  pressure  with  an  Independent,  calibrated  pressure  transducer.  Vt,0, 
represents  the  sum  of  the  ventilator -derived  tidal  volume  (pneumotachography)  and  TGI 
contribution.  A  Puritan  Bennett  7200  ventilator  with  a  conventional  non -disposable  non- 
heated  wire  circuit  was  utilized  with  a  spring  loaded  pressure  RV  (Bird.  Inc.  #04230) 
mechanically  ad|usted  to  achieve  a  threshold  pressure  =  P„,  In  the  ventilatory  circuits 
Inspiratory  limb.  Fixed  ventilatory  parameters  were  frequency  =  10  bpm.  P„,  =  35  cmHjO. 
resistance  ■  5  cmH;0/L/sec,  compliance  =  .02  L/cmH;0  and  IE  ratio  -1:1,  Catheter  flow 
rate  (VMlfl)  was  varied  as  follows: 


Vc.tr. 
IL/mM 

P„„ 

K(cmH,0) 

VWml) 

aulo-PEEP(cmHjO) 

RVon 

RVoff 

RVon 

RVoff 

RVon 

RVoff 

0 

35 

35 

687 

669 

0 

0 

2 

35 

37 

691 

722 

0 

0 

6 

35 

43 

699 

874 

1 

1 

10 

35 

51 

703 

1030 

2 

2 

CONCLUSIONS  Increasing  catheter  flow  rate  resulted  In  progressive  rise  In  both  PDMK 
and  Vt,01  with  the  conventional  PCV  circuit.  Insertion  of  a  RV  maintained  PDook  and  Vt^01 
constant    A  slight  Increase  In  auto-PEEP  was  noted  as  V,ath  Increased. 


CONTINUOUS  VS.  EXPIRATORY  PHASE  TRACHEAL  GAS 
INSUFFLATION  DURING  PRESSURE  CONTROL  VENTILATION: 
A  LUNG  MODEL  STUDY 

Hideaki  Imanaka.  Ml).  Vincent  Riggi,  RRT.  CBET,  Dean  Hess.  PhD.  RRT,  Ray  Ritz. 
RRT.  Robert  Kacmarek.  PhD.  RRT  Anesthesia  and  Respiratory  Care.  Massachusetts 
General  Hospital  and  Harvard  Medical  School.  Boston  MA. 

We  evaluated  the  effects  of  expiratory  phase  tracheal  gas  insufflation  (Ex-TGI)  and 
continuous  flow  TGI  (C-TGI)  on  ventilatory  parameters  during  pressure  control 
ventilation  (PCV)         Methods:  A  single  compartment  lung  model  was  configured 
with  an  artificial  trachea  into  which  an  8  mm  endotracheal  tube  was  positioned. 
C-TGI  was  established  with  a  16  G  catheter  inserted  through  the  endotracheal  tube 
and  positioned  2  cm  beyond  the  distal  tip.  Ex-TGI  was  established  with  a  solenoid 
valve  activated  by  a  Puritan  Bennett  7200ae  ventilator  such  that  flow  occurred  only 
during  the  expiratory  phase.  Ventilation  was  provided  with  PC  20  cm  H;0, 
respiratory  rate  of  1 5  /min,  and  PEEP  1 0  cm  H.O.  Inspiratory  times  (T,)  of  1 .0,  1 .5, 
2  0  and  2.5  s  were  used  with  TGI  flows  of  0,  4,  8,  and  12  L/min.  Lung  model 
compliance  (mL/cm  H.O)  and  resistance  (cm  H:0/L/s)  combinations  of  20/20.  20/5, 
and  50/20  were  used.  Statistical  analysis  was  done  with  a  one-way  ANOVA  followed 
by  Scheffe  test.  Results:  With  C-TGI.  peak  inspiratory  pressure  (PIP).  auto- 

PEEP  (PEEPi),  and  tidal  volume  (VT)  increased  significantly  (P  <  0.01 )  as  TGI  flow 
and  T,  increased.  With  Ex-TGI,  peak  inspiratory  pressure  remained  constant,  VT 
decreased  (P  <  001).  and  PEEPi  increased  significantly  (P  <  0.01 )  as  TGI  flow 
increased.  Mean  ±  SD  among  3  lung  mechanics  and  4  T,  are  shown  below. 


Continuous  flow  TGI  with  PCV 

TGI  PIP(cmH.O)  PEEPi(cmH.O)  VT  (mL) 

0  28.7±0.8  I.I  ±1.7       432±78 

4  30.5  ±2,2  1.6  ±1.9        456  ±  76 

8  33.1  ±4.2  2.6±2.0       492  ±  83 


Expiratory  phase  TGI  yvjlli  PCV 

PIP(cmH.O)  PEEPi(crnH,0)  VT  (mL) 

28.7±0.8  1.1  ±1.7       432  ±  78 

28.8  ±0.8  1.5±l.8       418±74 

28.8  ±0.7  2.2  ±1.8       399  ±  67 

12       36.5  ±  6.1      4.1  ±2.3       S36  ±  100  28.9  ±  0.7  3.4  ±  1.7       370±61 

Conclusions:  As  TGI  flow  or  T,  increased,  PIP  and  VT  increased  when  continuous 
flow  TGI  was  applied  in  PCV.  However,  PIP  did  not  change  and  VT  decreased 
during  expiratory  phase  TGI.  The  decrease  in  VT  is  likely  due  to  the  development  of 
auto-PEEP  during  Ex-TGI.  Auto-PEEP  increased  with  both  TGI  methods  as  TGI 
flow  and  T,  increased.  (Supported  in  part  by  Puritan  Bennett  Corp.) 


CONTINUOUS  VS.  EXPIRATORY  PHASE  TRACHEAL  GAS 
INSUFFLATION  DURING  VOLUME  CONTROL  VENTILATION: 
A  LUNG  MODEL  STUDY 

Hideaki  Imanaka.  MD.  Vincent  Riggi,  RRT.  CBET,  Dean  Hess,  PhD,  RRT,  Ray  Ritz, 
RRT,  Robert  Kacmarek,  PhD,  RRT.  Anesthesia  and  Respiratory  Care.  Massachusetts 
General  Hospital  and  Harvard  Medical  School.  Boston  MA. 


aluated  the  effects  of  expirator 
s  flow  TGI  (C-TGI)  on  ven 
ventilation  (VCV)  Methods:   A 

with  an  artificial  trachea  into  which  i 


phase  tracheal  gas  insufflation  (Ex-TGI)  and 
ilatory  parameters  during  volume  control 
single  compartment  lung  model  was  configured 
i  8  mm  endotracheal  tube  was  positioned. 


C-TGI  was  established  with  a  1 6  G  catheter  inserted  Ihrough  the  endotracheal  tube 
and  positioned  2  cm  beyond  the  distal  tip.  Ex-TGI  was  established  with  a  solenoid 
valve  activated  by  a  Puritan  Bennett  7200ae  ventilator  such  that  flow  occurred  only 
during  the  expiratory  phase    Ventilation  was  provided  with  VCV,  decelerating  flow 
pattern,  respiratory  rate  of  1 5  /min,  and  PEEP  1 0  cm  H,0.  The  tidal  volume  was  set 
at  zero  TGI  flow  at  each  of  four  inspiratory  times  (T,  =  1.0,  1.5,  2.0  and  2.5  s)  and 
maintained  at  the  set  level  as  TGI  flows  of  4,  8,  and  12  L/min  were  applied.  Lung 
model  compliance  (mL/cm  H,0)  and  resistance  (cm  H,0/L/s)  combinations  of  20/20. 
20/5,  and  50/20  were  used    Statistical  analysis  was  done  with  a  one-way  ANOVA 
followed  by  Scheffe  test.      Results:  With  C-TGI  and  Ex-TGI,  there  were  significant 
increases  in  peak  inspiratory  pressure  (d-PIP),  auto-PEEP  (d-PEEPi).  and  tidal 
volume  (d-VT)  (P  <  0.01 )  as  TGI  flow  increased.   However,  changes  in  PIP  and  Vt 
were  markedly  greater  with  C-TGI  than  with  Ex-TGI  (P  <  0.01).  Mean  ±  SD  among 
3  lung  mechanics  and  4  T,  are  shown  below. 


Continuous  flow  Kil  with  VCV 


TGI  d-PIPlcmH,Oid-PEKPi 

4  6  9    ±2.6      1.0  ±0.8 

8  13.1  ±5.0     2.5*1.7 

12  19.8  ±7.5     4.4  ±2.6 


d-V,(ml.) 
1 32  ±39 

247  ±76 


Expiratory  nhase  TGI  with  VCV 

d-PIPicmH,t))d-PEEPi  d-V^ml 

1.4  ±0  1        0.5  ±0.2  II  ±3 

2.9  ±0.2        1.4  ±0.3  22  ±4 

5.4  ±0.3        2.8  ±0.4  41  ±7 


Conclusions: 

PEEP  and  V, 


As  TGI  flow  increased,  increases  In  peak  inspiratory  pressu 
jeeun-cd  with  both  C-TGI  and  Ex-TGI  during  VCV.  Howev 
ch  smaller  increases  than  C-TGI    (Supported  in  part  by  Puri 


,  Ex-TGI 

n  Bennett 


TRACHEAL  GAS  INSUFFLATION  WITH  A  NEW  DOUBLE  LUMEN 
ENDOTRACHEAL  TUBE  A  COMPARISON  OF  CONTINUOUS  VS 
EXPIRATORY  TGI  DURING  PRESSURE  CONTROL  VENTILATION 

Max  Kirmse*  MP.  Hideaki  [manaka.  MD.  Harald  Mang-.  MD.  Dean  Hess,  PhD.  RRT. 

Robert  Kacmarek.  PhD,  RRT 

Anesthesiology  and  Respiratory  Care.  Massachusetts  Genera]  Hospital  and  Harvard  Medical  School. 

Boston.  MA      *Dept  of  Anaesthesia,  University  Erlangen-NQmberg.  Germanv 

Tracheal  Gas  Insufflation  (TGI)  with  a  small  open  ended  catheter  may  cause  auto- 
PEEP  and  mucosal  damage  Furthermore,  positioning  of  the  catheter  close  to  the 
carina  is  difficult  and  a  high  pressure  source  is  needed  to  drive  the  TGI-flow  We 
designed  a  double  lumen  endotracheal  tube  with  a  smaller  msufllanon  lumen  (=  3  5 
mm  ID  ),  and  a  bigger  lumen  (=  7  5  mm  ID  )  Gas  flow  through  the  smaller  lumen  is 
directed  towards  the  opening  of  the  bigger  lumen  by  a  nozzle  at  the  np  of  the  tube 
(Reverse  Flow  Design,  RFD)  To  evaluate  the  performance  of  our  tube,  we  compared 
the  effects  of  continuous  flow  TGI  (C-TGI)  and  expiratory  phase  TGI  (Ex-TGI)  on 
peak  inspiratory  pressure  (PIP),  auto-PEEP  (PEEPi)  and  tidal  volume  (V,)  during 
pressure  control  vennlanon  (PCV)  We  employed  a  single  compartment  lung  model 
with  an  artificial  trachea  into  which  the  TGI-tube  was  inserted  Ex-TGI,  using  the 
same  setup  as  C-TGI,  was  established  by  a  solenoid  valve  activated  by  a  Puritan 
Bennett  7200ae  ventilator  The  upper  pressure  level  was  set  at  20  cmHjO,  PEEP  at  1 0 
cmH:0,  and  respiratory  rate  at  1 5/Min  in  all  settings  Four  TGI  flows  (0,  4,  8,  1 2 
L/Min  )  and  inspiratory  Umes  (Ti  1.0.1  5,2  0  and  2  5  s)  were  applied  Three  different 
combinations  of  lung  mechanics  (compliance  [ml/cmH-Ol/resistance  [cmH:0/L/s]) 
were  used  20/20,20/5  and  50/20  Statisucal  analysis  was  done  with  a  one-way 
ANOVA  followed  by  a  Scheffe  test  Results:  As  TGI  flow  and  T,  increased,  C-TGI 
caused  a  significant  (p<0  01 )  increase  of  PIP  and  V7,  whereas  no  PEEPi  was  created 
During  Ex-TGI,  no  cnanges  in  PIP  or  VT  occurred  Again,  no  clinically  relevant 


MM 

value*  acrwi  3  lung  mrrh.nlct  and  4  mir.ir.iorv  time* 

Contuu 

our,  (lo»  TGI  with  PCV 

Eiplntory  phiu  TGI  with  PCV 

TGI 

PIP  |cmH201 

PEEPi  |cmH20] 

v,|mL| 

PIP 

PEEPi 

V, 

0 

28  8*0  8 

11*16 

422.    10 

28  8  *  0  8 

11*16 

422*80 

4 

305*2  3 

10*18 

445*  76 

28  9*08 

10*  18 

418*  78 

" 

33  3*4  3 

06*20 

481  *  80 

28  9  *  0  8 

05*1  9 

424  *  74 

13     I     36  9*6  44 

-034*24 

521  *  100 

28  8  *  0  8 

-0  5*2  2 

412*  101 

Conclusions:  1  Compared  to  straight  catheter  TGI.  the  RFD  reliably  prevents  auto- 
PEEP  at  all  clinically  occurring  TGI  flows  and  lung  mechanics  2  During  C-TGI 
adjustment  of  inspiratory  VT  is  necessary  in  order  to  avoid  excessive  inspiratory 
pressures  and  volumes  3  Regarding  barotrauma  only  Ex-TGI  seems  to  be  a  safe  way 
of  applying  TGI 

OF-95-152 


1 196 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


Monday,  December  4.  3:00-4:55  pm  (Rooms  230C-D) 


■iologieally   inert,    imolubla   gas  vhosi   Reynolds   numbs*-,    density 


70/30).      Esophageal   balloon  was    pla 


TCI   Flow 

ox    (N=5) 

Nitrox 

(N«5) 

70/30 

A  X 

80/20           A 

t                70/30 

0            0.34    (0.02) 

0.32  (o.o: 

) 

0.34    (0.0S) 

0.34    (.03) 

2            0.30    (0.01) 
4            0.26    (0.01) 

?2'7 

0.30    (0.01 

)        6.2 

0.34    (0.05)        0 
0.34    (0.02)        0 

0.34    (0.02 
0.33    (0.02 

6            0.22    (0.01) 

35 

0.24  (o.o: 

)      25 

0.30    (0.01)        l: 

.5        0.31    (0.02 

S            0.20    (0.01) 

41 

0.24    (0.01 

)      25 

0.26    (0.10)        17 

0.29    (0.02 

FINDINGS:   Tranetra 

cheal 

gas    insufflat 

ion  reduc 

es   measured  work  o 

f  breaching  in 

EXPIRATORY  TRACHEAL  CAS  INSUFLATJON  (E-TG1)  :  A  PROTOTYPE  DEVICE 
FOR  USE  WITH  THE  PB  7200AE  VENTILATOR 

VRiggi  RRT.CBET  H  Imanaka,  MD,  R.Ritz.  BA,  RRT,  D  Hess,  PhD,  RRT,  R  M.Kacmarek. 
PhD,  RRT.  Respiratory  Care  and  Anesthesia,  Massachusetts  General  Hospital  and  Harvard 
Medical  School,  Boston,  MA 

TGI  has  been  suggested  as  a  possible  method  to  reduce  PaC02  and  improve  PaO:  in 
mechanically  ventilated  patients  with  acute  respiratory  failure  TGI  may  be  continuous  or  phasic 
(during  exhalation  only)  The  consequences  of  continuous  TGI  are  increased  VT  and  PIP  Phase 
specific  or  E-TGI  was  explored  as  a  possible  solution  to  this  problem  Methods:  An  external  3 
way  solenoid  was  wired  to  the  exhalation  valve  solenoid  of  the  PB7200AE  ventilator  (PB  sol-4  . 
which  provided  the  phasic  electric  signal  needed  to  energize  and  de-energize  the  TGI  solenoid 
During  inspiration  the  TGI  solenoid  was  energized  and  the  gas  supply  in  the  Common  (COM) 
port  flowed  out  the  Normally  Closed  (N.C-J  port.  During  exhalation  the  solenoid  was  de- 
energized  and  the  flow  was  diverted  to  the  Normally  Open  (MO.)  port.  The  source  flow  to  the 
COM  port  was  supplied  by  a  blender  to  a  flowmeter  through  a  humidifier  (Cascade  IA).  A  #5 
French  catheter  inserted  into  an  ETT  was  connected  to  the  N  O  outlet.  The  N.C.  outlet  provided 
a  path  to  atmosphere  to  which  we  attached  an  identical  «5  French  catheter  Delivered  flow 
partem  and  system  pressure  in  the  TGI  design  were  determined  Appropriate  location  of  the 
humidifier  was  explored  Results:  With  the  solenoid  placed  downstream  to  the  humidifier,  the 
flow  partem  resembled  a  square  wave  with  a  rise  time  of  120  ms  and  a  fall  time  of  210  ms 
When  placed  upstream  the  wave  form  was  severely  dampened  and  did  not  return  to  zero  As 
flow  increased,  catheter  resistance  created  a  rising  back-pressure  in  the  TGI  system  PIP  a 
were  significantly  smaller  in  E-TGI  than  in  continuous  TGI  (top  table).  Delivered  flow  v 
nearly  the  same  as  the  set  value  (bottom  table).  The  ventilator's  diagnostic  software  did  n 
generate  any  error  codes  after  more  than  72  hours  of  testing. 


Jid  VT 


ER 

E 

R 

C-TGI 

E-TGI|noTGI 

C-TGI 

E-TGI 

no  TGI 

C-TGI 

E-TGI 

noTGl 

TGI  (Lrnin) 

i: 

12          0 

12 

i: 

0 

12 

12 

0 

PIP(cmH20) 

398 

29.3 

28.2 

41.4 

2«2 

29 

31  : 

28 

28 

V^L) 

051 

36 

39 

.61 

38 

42 

58 

50 

59 

ER:  C=  02  L/cm  H,0.  R=20  cm  H,0/L/s,  E:  C-.02  L/cm  H,0,  R=5/cm  HjO/L/s; 

R:  C-  05  L/cm  H,0,  R=20  cm  H,0/L/s 

TTL  lung  model  PB7200AE  ventilator,  PCV  20  cm  H20,  Rate  15/min, +10  peep,  FiO,21"/ 

Tinsp  2  seconds,  ETT  ID  8mm 


TGI  flow  (L  mini 

J 

8 

10 

12 

TGI  system  pressure  (psi) 

6  3 

14  5 

193 

24.2 

TGI  catheter  (L/min) 

4  4 

8  1 

95 

117 

:  Our  system  provided  a  consistent  phasic  square  wave  of  expiratory  TGI  with 
minimal  manufacturing  Further  evaluation  of  the  humidifying  system  as  well  as  any  possible 
consequences  from  attaching  to  the  exhalation  valve  signal  must  be  studied. 


Tracheal  Gas  Insufflation  in  a  Mechanically  Ventilated  Canine  Model  with  Railed 
Intracranial  Pressure  Thomas  Maiinowski.  Thomas  O'Callahan,  Clifford  Douglas,  Charles 
Kean,  Mark  Often,  Departments  of  Respiratory  Care.  Surgery,  and  Animal  Research.  Loma 
Linda  University  Medical  Center.  Loma  Linda,  CA 

Introduction  Continuous  Tracheal  Gas  Insufflation  (TGI)  of  fresh  gas  into  the  central  airways 
has  been  proposed  as  an  adjunctive  COj  clearance  technique  which  helps  minimize  airway 
pressures  during  mechanical  ventilation  One  of  the  mechanisms  by  which  TGI  is  reported  to 
work  is  by  washing  out  central  airways  deadspace    We  hypothesize  that  TGI  would  be 
beneficial  in  reducing  arterial  C03  in  a  raised  intracranial  pressure  (ICP)  canine  model,  a 
population  in  which  it  is  undesirable  to  elevate  ventilatory  pressures  or  allow  permissive 
hypercapnea,  and  that  anenaj-io-cnd  -tidal  carbon  dioxide  comparisons  would  substantiate  the 
reduction  in  deadspace  Methodi  Six  (6)  dogs  ( 1 0  5- 1 2  kg!  were  sedated  with  non-barbiturate 
anesthesia  and  managed  with  central  and  arterial  lines  Endotracheal  intubation  and  volume 
ventilation  (tidal  volume  10-15  ml/kg,  FIOj  -  3,  PEEP  =  0)  with  a  Servo  900B  ventilator 
maintained  normocarbia  A  7  Fr  pediatric  feeding  tube  served  as  the  TGI  catheter,  and  was 
placed  in  the  endotracheal  tube  via  bronchoscopic  adapter  TGI  flow  during  insufflation  was  5 
1pm  The  TGI  catheter  tip  was  located  approximately  I  cm  above  the  carina  Mean  airway 
pressure  (MAP)  and  end-tidal  CC+i  (PetCOj)  values  were  monitored  via  a  catheter  tip  distal  to 
the  TGI  catheter  Catheter  and  airway  pressure  line  placement  was  verified  via  bronchoscopy 
An  intracranial  pressure  bolt  monitored  ICP  during  the  trial  A  saline-filled  balloon  catheter 
placed  in  the  epidural  space  simulated  the  cranial  space  occupying  lesion  Results  Statistical 
analysis  by  t  test  identified  significant  differences  in  ICP,  PaCOj,  and  cerebral  perfusion  pressure 
(CPP)  (p<  0 1 )  between  injury,  TGI  nadir,  and  post  injury    There  was  no  significant  difference 
in  peak  (Ppk)  or  MAP  at  the  three  levels  (p<  01 )    The  artenal-to-end-tidal  carbon  dioxide 
gradient  showed  a  statistically  significant  increase  during  TGI  when  compared  to  injury  pre 
TGI(p<  05) 


Injury 

TCI 

nadir 

Post 


PaCO,      PerCO,     MAP 

mmHg       mmllR       cm  U,0 
43  +  3         40  +  4  5      4*13 


38  j 


r  1  3 


Ppk  ICP  CPP 

cm  M]0  mmHg  mmHg 

14  *3  41  +  12  6  33+10.5 

14  +  24  27  +  9.5  53  +  76 

14  +  1  37+13  43  +  7 


Conclusions  1 )  Preliminary  experience  with  continuous  TGI  at  5  Ipm  has  demonstrated  it  to  be 
effective  in  reducing  ICP  in  the  mechanically  ventilated  head  injury  model  by  augmenting  CO] 
clearance,  as  evidenced  by  the  reduction  in  arterial  CGy  Furthermore,  the  improvement  in 
ventilation  was  accomplished  without  an  increase  in  peak  or  mean  airway  pressures  TGI  may 
be  particularly  beneficial  in  treating  patients  with  raised  ICP.  a  group  whom  may  not  tolerate 
permissive  hypercapnic  ventilatory  strategies  2)  The  arterial  -  end  tidal  CO;  gradient  increased 
during  TGI    This  increase  would  be  consistent  with  a  traditional  interpretation  of  increased 
deadspace.  but  Is  most  likely  attributable  to  increased  C03  clearance  from  fresh,  TGI  gas 


TRACHEAL  GAS  INSUFFLATION:  A  BRIDGE  TO  HIGH  FREQUENCY 
VENTILATION.  Hussein  N.  El-Lessy,  RRT,  Perinatal/ 
Pediatric  Specialist.  James  C.  Cunningham,  MB, 
Pediatric  Pulmonoloqlst ■  Cook  Children's  Medical 
Center,  Fort  Worth,  Texas. 

In  satisfying  targeted  parameters,  pulmonary  Integrity 
is  often  compromised  by  high  transalveolar  pressures 
provided  by  conventional  ventilation.  Tracheal  gas 
insufflation  (TGI)  provides  a  solution  via  a  less 
invasive  method  of  ventilation:  dead  space  ventilation. 
This  is  accomplished  by  the  Insertion  of  a  flexible 
catheter  Into  an  ET  tube.  By  positioning  the  mouth  of 
the  catheter  proximal  to  the  carina  and  providing  a 
modest  flow  of  equal  F102  concentration,  a  Jet  of  gas 
projects  for  a  sufficient  distance  past  the  orifice  of 
the  catheter  to  effect  dead  space  ventilation.  During 
TGI,  PaC02  falls  In  a  direct  but  non-linear  relation  to 
the  rate  of  flow  provided  through  the  catheter.  Two 
cases  were  evaluated  for  effectiveness.  Case  1.  An  8.6 
kg  female  presented  with  aspiration  pneumonitis  and 
subsequent  RDS .  Mechanical  ventilation  utilizing  high 
rates  and  high  PIPs  failed  to  provide  adequate 
ventilation  (pH  7.30,  PaC02  93  torr,  and  Pa02  64  torr), 
and  hemodynamic  stability  (pulmonary  vascular 
resistance  (PVR)  2020  dynes,  mean  pulmonary  artery 
pressure  (MPAP)  48  torr,  and  central  venous  pressure 
(CVP)  14  torr).  Following  initiation  of  TGI  at  2  1pm  of 
equal  F102,  ABGs  revealed  a  modest  improvement  in 
ventilation  (pH  7.34,  PaC02  69  torr,  and  Pa02  83  torr). 
Hemodynamic  improvments  ensued  with  a  50%  reduction  in 
PVR  to  1050  dynes,  MPAP  34  torr,  and  CVP  10  torr.  Case 
2.  An  8.6  kg  male  with  bilateral  pulmonary  transplants 
presented  with  respiratory  insufficiency  of  unknown 
etiology.  Conventional  ventilation  utilizing  high  rates 
and  high   PIPs  proved  futile  in  eliminating  PaC02 
levels  of  over  150  torr,   pH  of  6.90,  Pa02  83  torr,  PVR 
of  800  dynes,  MPAP  of  35  torr,  and  pulmonary  artery 
wedge  pressure  (PAWP)  of  19  torr.  Immediately  following 
initiation  of  TGI  at  2  1pm  of  equal  F102,  PaC02  levels 
plummeted  to  64  torr  (pH  of  7.33,  Pa02  of  214  torr,  PVR 
of  695  dynes,  MPAP  of  23  torr,  and  PAWP  of  11  torr).  It 
is  easy  to  discern  the  potential  for  this  experimental 
form  of  assisted  ventilation  in  the  more  passive 
treatment  of  C02  retention  and  pulmonary  hypertention. 

OF-95-191 


Respiratory  Care  •  November  '95  Vol  40  No  11 


197 


Monday,  December  4,  3:00-4:55  pm  (Rooms  230C-D) 


PARTIAL  LIQUID  VENTILATION:    HISTOLOGIC 
DIFFERENCES  BETWEEN  HIGH  FREQUENCY 
VENTILATION  AND  CONVENTIONAL  VENTILATION. 

Kendra  M.  Srailh.MD.  Dennis  R.  Binp.RRT.  Raye-Ann  deRegnier,  MD, 
Pat  A  .  Meyers,  RRT.  Susan  C.  Simonlon,  MD,  Stephen  J.  Boros,  MD, 
Mark  C.  Mamrael,  MD.  Infant  Pulmonary  Research  Center,  Children's 
Health  Care  -  St.  Paul. 

Partial  liquid  ventilation  (PLV),  when  compared  to  conventional 
ventilation  (CV),  better  preserves  lung  architecture  in  animal  studies.  High 
frequency  ventilation  (HFV)  causes  less  alveolar/airway  disruption  from 
barotrauma  in  animals  and  humans.  No  studies  have  investigated  lung 
pathology  following  PLV/HFV.  We  hypothesized  that  PLV  would  produce 
less  lung  damage  after  prolonged  ventilation  when  compared  to  CV,  and 
that  PLV/HFV  would  further  reduce  lung  damage.  We  induced  lung  injury 
with  saline  lavage  (Pa02  £  60  torr,  Fi02  1 .0)  in  36  newborn  piglets.  After 
stabilization  on  CV  with  gas,  animals  were  randomized  to  one  of  five 
groups  for  20  hrs:  1)  CV  with  gas  ventilation  (n=8);  2)  PLV  with  CV  (n=7); 
3)  PLV  with  jet  ventilation,  IMV  7  (Bunnell;  n=7);  4)  PLV  with  oscillation 
(SensorMedics  3100;  n=7);  or  5)  PLV  with  flow  interruption,  IMV  7 
(Infrasonics  Infant  Star;  n=7).  Animals  in  groups  2-5  received 
preoxygenated  perfluorocarbon  (LiquiVent  ®,  Alliance  Pharm.Corp.)  to 
approximate  FRC  by  assessment  of  ET  tube  meniscus,  which  was  checked 
hourly  for  replacement  of  evaporative  losses.  Ventilator  support  was 
adjusted  to  normalize  blood  gases.  Animals  remained  supine  with  20°  head 
elevation.  At  autopsy,  lungs  were  inflated  to  40  cm  H20,  clamped,  then 
fixed  in  formalin.  Slides  from  animals  surviving  >16  hrs  (n=29)  were 
scored  by  a  pathologist  (SS)  bhnded  to  ventilation  type.  We  scored  alveolar 
and  interstitial  inflammation  and  hemorrhage,  edema,  atelectasis,  necrosis, 
and  presence  of  hyaline  membranes  on  a  0-4  scale.  Upper  (UL)  and  lower 
lobes  (LL)  were  scored  separately,  then  summed.  Scores  were  analyzed 
using  the  Kruskal-Wallis  test.  We  assessed  group  differences  with  the 
Newman-Keuls  test-  Total  injury  scores  were  significantly  lower  in  all  PLV 
groups  compared  to  CV-gas  (p<0.05).  There  were  no  differences  in  UL 
scores;  LL  scores  were  significantly  lower  in  all  PLV  groups  (p<O.05). 
CV-gas  produced  more  alveolar  inflammation,  edema,  atelectasis,  and 
hyaline  membrane  formation  than  did  any  type  of  PLV  (p<0.001). 
Conclusion:  PLV,  with  CV  or  HFV,  reduces  lung  damage  after  prolonged 
ventilation.  Similar  injury  scores  in  UL  suggest  unequal  perfluorocarbon 
distribution,  with  greater  protection  in  dependent  lung  regions. 
(LiquiVent  ®,  provided  by  Alliance  Pharm.  Corp.) 


TIME  COURSE   OF  BLOOD  GAS   AND   LUNG 
COMPLIANCE    CHANGES    DURING    PARTIAL    LIQUID 
VENTILATION  IN  AN  ANIMAL  MODEL.   Dennis  R.  Bino.  RRT. 
Kendra  M.  Smith  ,  MD,  Raye  Ann  deRegnier,  MD,  Pat  A.  Meyers, 
RRT,  Stephen  J.  Boros,  MD,  Mark  C.  Mammel,  MD.  Infant 
Pulmonary  Research  Center,  Children's  Health  Care  -  St.  Paul. 

Partial  liquid  ventilation  (PLV)  using  perfluorocarbons  has  been 
shown  to  rapidly  improve  oxygenation  in  animals  and  humans 
with  severe  lung  disease.  However,  the  time  course  of  this  change 
has  not  been  reported.  We  evaluated  the  rate  of  blood  gas  and 
lung  compliance  (CI)  changes  during  the  first  30  minutes  of  PLV 
with  preoxygenated  perfluorocarbon  (LiquiVentTM,  Alliance 
Pharm.  Corp.)  in  a  neonatal  lung  injury  model.  We  induced  lung 
injury  (Pa02  <  60  torr,  Fi02  1.0)  with  multiple  saline  lavage  in  36 
newborn  piglets,  then  instilled  an  intratracheal  volume  of 
LiquiVent™  to  approximate  FRC  (30-50  ml/  kg)  by  observing  ET 
tube  meniscus.  Animals  received  ventilation  using  the  DrSger 
Babylog  ventilator  at  constant  tidal  volumes,  PEEP,  Fi02  and 
frequency.  We  measured  arterial  blood  gases  after  lavage  (before 
PLV),  and  at  5.  10,  15,  and  30  minutes  of  PLV.  We  also  measured 
dynamic  and  static  CI  after  lavage  and  at  30  min.  after  PLV.  Data 
were  analyzed  using  one  way  ANOVA  or  paired  t-  tests,  as 
appropriate.   Post-  hoc  testing  used  Newman-  Keuls  multiple 
range  analysis. 


PH 

PC02 

P02 

ci  (dyn) 

CI  (sialic) 

Paw 

before  PLV 

7  11:0  15 

71123 

48110 

0  60:0  2 

0  6510  3 

11  6:1  4 

5  mm 

7.1510.13 

64115 

154ll0lt 

7.17±0.12 

63:17 

1711106 

15  min 

7.2010.10 

57:11' 

2041106 

30  min 

7  26:0  10' 

52113 

25311 13* 

0.9210  2f 

0  B6l0.3t 

10  6:2  7f 

•p<0.05  vs  before  PLV;  tp<0.01  vs  before  PLV;  +p<0.01  vs  5  min. 

All  parameters  improved  over  the  study  period,  in  spite  of  a 
significant  fall  in  Paw  (p<0.05).  Arterial  P02  improved  most 
rapidly,  then  continued  to  gradually  increase.  PC02  improved 
more  slowly,  but  was  significantly  lower  at  15  minutes  and 
sustained  at  30  minutes.  Changes  in  pH  were  significant  at  30 
minutes.  Conclusions:  PLV  rapidly  improves  lung  mechanics  and 
gas  exchange,  resulting  in  decreased  pressure  requirements  to 
maintain  tidal  volumes. 


QUICK-FILL  VS  SLOW-FILL  WITH  PARTIAL  LIQUID  VENTILATION 

CR  Wise.  BS.  RRT:  RB  Hirschl,  MD;  T  Pranikoff,  MD;  RJ  Shreiner,  MD; 

P  Gauger,  MD;  RH  Bartlett  MD;  CF  Haas,  MLS,  RRT. 

Departments  of  Respiratory  Care  and  Surgery,  University  of  Michigan 

Medical  Center,  Ann  Arbor  Ml 

INTRODUCTION:  Developing  bedside  methods  to  deliver  new  modalities  is 
done  by  trial,  error  and  ingenuity.  Techniques  used  during  preliminary 
animals  studies  are  often  found  awkward  or  inadequate  during  patient  trials. 
This  study  describes  two  methods  of  instilling  perflourocarbon  ((PFC) 
Alliance  Pharmaceutical  Corp,  San  Diego  CA)  during  partial  liquid 
ventilation  (PLV).  METHODS:  All  patients  were  placed  on  time-cycled 
pressure-controlled  ventilation  (7200ae,  Puritan  Bennett,  Carlsbad  CA)  using 
normal  to  inverse  I:E  ratios.  All  patients  were  placed  on  Fi02  of  1.0  during 
each  fill.  Instillation  method  one  (Quick-fill)  involved  briefly  removing 
patients  (n=2)  from  the  ventilator,  inserting  a  glass  funnel  into  the 
endotracheal  tube  (ETT)  and  instilling  5  mL  of  PFC  while  observing  Sp02 
and  tidal  volume  (Vt).  Patients  were  then  reconnected  to  the  ventilator  and 
monitored.  With  method  two  (Slow-fill)  patients  (n=3)  remained  on  the 
ventilator.  A  bronchoscopy  adapter  was  inserted  between  the  ETT  and  the 
patient  wye.  The  glass  funnel  was  connected  to  a  red  rubber  suction  catheter 
which  was  inserted  into  the  adapter.  Hemostats  clamped  the  catheter  to 
regulate  flow  of  liquid  as  5  mL  of  PFC  was  instilled.  Vt  and  Sp02  were 
monitored.  RESULTS:  Quick-fill  (QF)  had  an  initial  drop  in  Vt  to  3%  of 
baseline;  Slow-fill  (SF)  to  81%.  At  1-2  min  post  instillation  40%  vs  90%  and 
at  3-5  min  75%  vs  106%  for  QF  vs  SF  respectively.  Recovery  of  Vt  to  90% 
of  baseline  ranged  from  4-22  min  for  QF  and  0-3  min  for  SF.  Sp02  dropped 
in  relation  to  Vt-  Effect  of  PFC  filling  on  each  patients'  Vt  shows: 
Effect  of  PFC  Fill  on  VT 


pre-fill      Omin        1-2  min     3-5  min 
post  post  post 

CONCLUSIONS:  Slow  instillation  allows  the  PFC  to  go  into  the  peripheral 
areas  of  the  lung  during  PFC  administration,  without  a  severe  reduction  in 
VTandSp02. 


PRESSURE  VOLUME  CURVES  DURING  PARTIAL  LIQUID  VENTILATION 

Constance  R.  Wise.  BS.  RRT:  Ronald  B.  Hirschl,  MD; 

Kenneth  B.  Bandy,  BA,  RRT;  Carl  F.  Haas,  MLS,  RRT; 

Robert  H.  Bartlett,  MD.  Departments  of  Respiratory  Care  and  Surgery, 

University  of  Michigan  Medical  Center,  Ann  Arbor  MI 

INTRODUCTION:  Ventilation  monitoring  during  mechanical  ventilation 
includes  waveform  analysis.  Pressure-volume  (P/V)  curves  help  to  better 
understand  the  interplay  between  gas  dynamics  and  lung  compbance.  We 
describe  the  use  of  P/V  curves  during  partial  liquid  ventilation  (PLV). 
METHODS:  Ten  patients  were  instilled  with  perflourocarbon  ((PFC) 
Alliance  Pharmaceutical  Corp,  San  Diego  CA),  with  either  up  to  40  mL/kg  of 
ideal  body  weight  or  until  a  fluid  meniscus  was  seen  at  end-exhalation  in  the 
ETT.  Gas  ventilation  was  performed  using  pressure  control  ventilation 
(7200ae,  Puritan  Bennett,  Carlsbad  CA).  P/V  curves  were  obtained  with  a 
respiratory  mechanics  monitor  (CP-100,  BICORE,  Irvine  CA)  prior  to, 
during  and  24  hours  after  PFC  administration.  PFC  could  be  administered 
daily  for  7  days.  RESULTS :  Patients  demonstrated  similar  changes  in  the 
shape  of  the  P/V  curves  before,  during  and  after  administering  PFC.  These 
changes  appeared  to  correspond  with  PFC  fluid  in  the  central  airways. 
Figure  A  shows  a  normal  P/V  curve  prior  to  instilling  PFC.  Figure  B  shows 
a  characteristic  "beak"  during  early  inspiration,  corresponding  with  PFC  in 
the  central  airways.  Figure  C  shows  the  return  to  a  pre-fill  P/V  curve. 


F1,A 

FijB 

FIjC 

1    r^ 

/ 

s 

T 

^ 

7 

CONCLUSION:  Although  the  monitoring  of  VT,  Sp02,  and  MAP  indicate 
the  patient's  tolerance  of  PFC  administration,  the  use  of  P/V  curves  may  be 
beneficial  in  deciding  the  volume  of  PFC  instilled  during  PLV.  P/V  curves 
demonstrate  PFC  in  the  central  airways  and  its  removal  from  the  central 
airways  via  evaporation  and/or  alveolarization. 


1198 


Respiratory  Care  •  November  '95  Vol  40  No  11 


RESENTING 

THE  FIRST 

PORTABLE 

VENTILATOR 

THAT      g 

DOESN'T 

HAVE  TO 

^POLOGIZE 

FOR  BEING 

PORTABLE! 


Respiratory  Care  Magazine, 
anuary  1992,  Vol.37,  No.  1. 


Blender     ^ 


$■» 


Compare  Uni-Vent      to  any  other  portable 

ventilator  and  you  will  quickly  see  why 

the  Model  750  is  in  a  class  by  itself. 


■^ARM  STATUS 


•  Control,  Assist-Control  and  SIMV  operating  modes, 
optional  electronic  demand  valve  -  all  PEEP  compensable! 

Comprehensive  alarm  system  and  automatic  continuous  system 
self-checks  for  maximum  safety! 

•  Easy-to-operate,  logical  control  groupings,  simplify  personnel  training! 

•  Operates  from  internal  battery  or  external  power  -  consumes  no  gas! 

•  High-reliability,  electronic  circuitry  is  unaffected  by  changes  in  altitude! 

Circle  1 1 5  on  reader  service  card 
Visit  AARC  Booth  224  in  Orlando 

For  more  information  on  the  Uni-Vent™  Model  750,  or  the  name  of  your  local  Representative,  call  Impact  today! 
IMPACT  Instrumentation,  Inc.,  27  Fairfield  Place,  P.O.  Box  508,  West  Caldwell,  NJ  07006  1-800/969-0750 


Tuesday.  December  5,  1:00-2:55  pm  (Rooms  230A-B) 


A  PROSPECTIVE,  RANDOMIZED  TRIAL  OF  7  DAY  VENTILATOR  CIRCUIT  CHANGES 
VERSUS  NO  ROUTINE  CIRCUIT  CHANGES  FOR  PATIENTS  REQUIRING  PROLONGED 
MECHANICAL  VENTILATION.  Patricia  Silver.  RRT,  ME.  Linda  Hossin,  RRT,  Rodger 
Richards,  CRTT,  Mona  Hearns,  CRTT,  Steven  Shapiro,  M.D.,  Victoria  Fraser,  M.D., 
Marin  Kollef,  M.D.  Pulmonary  and  Critical  Care  Division,  Washington  University 
School  of  Medicine,  and  The  Departments  of  Respiratory  Therapy  and  Infection 
Control,  Barnes  Hospital  and  Jewish  Hospital,  St.  Louis,  MO. 

Introduction:  Preliminary  studies  performed  to  date  suggest  that  ventilator 
circuit  changes  can  be  safely  extended  beyond  48  hours  without  increasing  the  risk 
of  ventilator-associated  pneumonia  (VAP).  However,  the  maximum  safe  duration 
between  breathing  circuit  changes  is  currently  unknown  as  suggested  by  the  Centers 
for  Disease  Control  and  Prevention  (Infect  Control  Hosp  Epidemiol  1994;  15:587). 
Therefore,  we  performed  a  two  center  study  to  determine  if  a  practice  of  not 
routinely  changing  ventilator  circuits  in  patients  requiring  prolonged  mechanical 
ventilation  (>  5  days)  is  associated  with  an  increased  incidence  of  nosocomial 
pneumonia.  Methods:  Prospective,  randomized  trial  comparing  seven  day  breathing 
circuit  changes  to  no  circuit  changes  with  the  main  outcome  measure  being  the 
)  of  VAP.  Breathing  circuits  were  only  changed  in  the  group  randomized 
circuit  changes  if  they  appeared  soiled.  Results:  (following  a  scheduled 
'  of  the  data  at  6  months). 


7  day  circuit  change 
In  =   1201 

Age,  v': 

58.9  ±  19.7 

APACHE  II  score: 

1B.4J.7.9 

Organ  Failure  Score: 

1.9  ±  0.7 

PaCVFiO,: 

242  ±  125 

Circuit  changes: 

1.4  ±  1.9 

Hospital  LOS,  d: 

31.9  +.  23.3 

Duration  of  MV.  d: 

14.7i  12.0 

VAP: 

l*cases  VAP/1000 

ventilator  days) 

28  I23.3%> 
15.8 

No  ( 


inge  P  value 
In  -  128) 

61.8  _t  17.2  0.23 

20.3  ±  8.5  0.06 


2.2  ±  0.8 

0.09 

232  ±  126 

0.53 

0.07  +.0.3 

<  0.001 

29.9  i  '8.2 

0.45 

15.2  +.  12.7 

0.77 

31  (24.2%) 

0.87 

15.9 

NS 

(APACHE   -  Acute  Physiology  and  Chronic  Health  Evaluation;  LOS   =   Length  of 
Stay;  MV  ■  mechanical  ventilation;  VAP  =  ventilator-associated  pneumonia.) 
Conclusions:    These  Interim  results  suggest  that  the  occurrence  of  VAP  is  not 
significantly  increased  in  patients  requiring  prolonged  mechanical  ventilation  who 
receive  no  routine  breathing  circuit  changes. 

OF-95-002 


IMPACT  OF  SEVEN  (7)  DAY  VENTILATOR  CIRCUIT  CHANCES  ON   RATES  OF 
LOWER  RESPIRATORY  TRACT  INFECTION  (LRI)  IN  A  PEDIATRIC 
POPULATION.    A  PILOT  STUDY 

Billy  Lamb,  BS,  RRT,  CPFT,  Charles  Foster,  BA,  RRT,  Joyce  Hayes.  RN,  M.P. H. 
Cardinal  Glennon  Children's  Hospital,  St.  Louis,  MO. 

INTRODUCTION:  Seven  day  ventilator  circuit  change  (SDVCC)  schedules  are  being 
adopted  by  many  hospitals  due  to  cost  containment  and  based  upon  data  that  show 
that  SDVCC  in  not  associated  with  an  increased  incidence  of  loner  respiratory 
infection  (LRI).    We  hypothesized  that  SDVCC  would  not  increase  the  LRI  rate  in  our 
pediatric  ventilator  patient  population  and  that  quantitative  cultures  of  the 
inspiratory  ventilator  circuits  would  show  no  growth  after  seven  days.  METHOD:    Due 
to  cost  containment  strategy,  we  choose  NOT  to  use  a  prospective  randomized 
methodology;  therefore,  as  a  pilot,  we  implemented  SDVCC  for  ail  patients  in  our 
intensive  care  units.  Due  to  concerns  of  the  physician  faculty,  as  a  quaJity  control, 
inspiratory  ventilator  circuit  cultures  were  performed  (sampling  at  the  outlet  of  the 
humidifier,  the  patient  wye  and  the  temperature  probe  inlet)  using  quantitative  culture 
technique  on  each  study  patient's  \entilator  circuit  after  seven  days.  Routine 
surveillance  from  1989  -  1993  showed  no  growth  in  cultures  of  inspiratory  ventilator 
circuits  of  patients  receiving  M/W/F  circuit  changes.  Patients  that  were  ventilated  < 
seven  days  were  cicluded  from  the  study.  LRi/1000  ETT  DAY  (LRI/ETT)  were 
monitored.  LRI  was  defined  according  to  1988  CDC  guidelines  for  nosocomial 
pneumonia.  The  control  group  consisted  of  all  tentilated  patients  .(an. -April  1993 
(MAV/T  circuit  changes),  the  study  group,  all  ventilated  patients  Jan.-  April  1994 
i  SDVCC).  The  control  group  consisted  of  49  patients,  mean  age  9.63  months  (range 
0-180;  median  I  month  ) .  The  study  group  consisted  of  46  ventilator  patients,  mean 
age  8.04  months  (range  0-160;  median  0)  RESULTS:  Quantitative  cultures  of  the 
vent,  circuits  revealed  no  growth  in  the  study  group;  retrospective  data  show  no  growth 
in  cultures  in  the  control  group.  LRI  for  the  control  group  =  13;  LRI  for  the  study 
group  =  10.  LRI/ETT  in  the  Control  group  were  4.36  (13  LRI;  3018  ETT  days); 
LRI/ETT  for  the  Study  group  were  3.30  (10  LRI;  3150  ETT  days).  These  data  show  no 
significant  difference  in  LRI/ETT  between  the  control  group  and  study  group  (XJ  ■ 
0.32).  Circuit  cost  for  the  control  group  was  S4.55  per  ventilator  day;  the  study  group 
(SDVCC)  $2.49  per  ventilator  day.  EXPERIENCE:  Our  study  methodology  was  not 
designed  to  prove  SDVCC  Statistically  Related  to  lowering  Lower  Respiratory 
Infections.  Variables  such  as  da>s  on  antibiotics,  days  intubated,  ventilator  type,  NG 
tube  days,  patient  position,  diagnosis  and  others  may  contribute  to  the  incidence  of  LRI 
in  ventilated  patients.  CONCLUSION:  Pediatric  SDVCC  are  not  associated  with  an 
increase  in  LRI  &  significantly  reduce  cost  as  compared  to  M/W/F  vent  circuit 
changes.  Prospective,  randomized  studies  are  needed  to  determine  if  circuit  change 
frequency  is  statistically  related  to  lower  LRI  rates  in  ventilated  patients;  multiple 
variables  in  this  patient  population  make  proving  this  hypothesis  very  challenging.  The 
SDVCC  process  was  continued  at  our  hospital. 

OF-95-005 


Introduction:  There  is  little  dala  reported  from  the  subacute 
environment  in  regards  to  VAP.   We  compared  our  VAP  results  in  our 
subacute  ventilator  unit  to  4  published  abstracts  in  Respiratory  Care  (Vol 
39,  No.  11,  pgs.  1107   •  1108)  from  acute  care  facilities  with  adult 
patient  populations  and  7  day  ventilator  circuit  change  frequency.    Also 
reported  are  the  nosocomial  pneumonia  rates  for  patients  with 
tracheostomies  but  not  receiving  mechanical  ventilation.   Method:  55 
patients  were  studied  using  clinical  criteria  of  presence  of  leukocyctosis, 
fever,  purulent  secretions  and  new  chest  infiltrates.   All  patients  were 
considered  ventilator  patients  if  they  received  6  hours  or  more 
mechanical  ventilation  per  day.   Once  a  patient  was  able  to  achieve  24 
consecutive  hours  of  spontaneous  breathing  that  individual  would  be 
placed  into  the  tracheostomy  group.    Ventilator  patients  used  the 
Infrasonics  Aduli  Star  or  Acquitron  LP-6  ventilators  cquiped  with 
AnaMed  heated  wick  circuit  (Simplex  Medical  Systems,  Inc   No.  A8351 
or  A2668)  with  AnaMed  Water  Pump  (No   A8000)  fed  with  IP1  3000  ml 
water  (IPI  Medical  Products,  No. 3175).   Ventilator  circuits  were  changed 
at  7  day  intervals.    All  tracheostomy  patients  used  Misty-Ox  Multi-Fit 
nebulizers  (Medical  Moulding.  No   44IAt  Hudson  RC1  tracheostomy 
masks  and  drainage  bags  (No.  1075  and  No.  1742)  with  IPI  corrugated 
tubing  and  1000  ml  water  (IPI  Medical  Products,  No.  3100  and  No. 
1065).   Aerosol  circuits  were  changed  three  times  per  week.   All  patients 
admitted  to  the  ventilator  unit  received  on-site  pre-admission  clinical 
evaluations  which  identified  evidence  of  abnormal  chest  film  or  pre- 
existing pneumonia  with  concurrent  review  over  the  6  month  period  of 
the  study.  Results:   32  were  admitted  as  ventilator  patients  and  23  were 
admitted  as  tracheostomy  patients.   The  VAP  rate  for  ventilator  patients 
was  1.9  per  1000  ventilator  days.  The  rate  of  nosocomial  pneumonia  for 
tracheostomy  patients  was  2.0  per  HXX)  tracheostomy  days.  The 
aggregate  rate  was  2.0  /1000  days.  The  VAP  rate  from  the  published 
abstracts  ranged  from  2.8  to  8.62/1000  ventilator  days  with  an  average  of 
6.08.  Conclusions:  The  VAP  rate  was  lower  in  the  subacute 
environment  than  the  acute  care  setting.  There  was  no  significant 
difference  in  facility  acquired  pneumonia  between  patients  receiving 
mechanical  vcntilaiion  and  the  tracheostomy  patients. 


EXTENDING  VENTILATOR  CIRCUIT  CHANGE  INTERVAL 

BEYOND  TWO  DAYS  REDUCES  LIKELIHOOD  OF  VENTILATOR 

ASSOCIATED  PNEUMONIA  (VAP) 

I.  Fink.  MS.  RRT.  S.  Krause,  RN,  L.  Barrett,  MS. 

Hines  VA  Hospital  and  Loyola  Univ.  Chicago,  Hines  IL. 

Ventilator  circuits  have  been  associated  with  VAP  and  the  CDC 
recommends  >48  hours  change  intervals.  To  determine  impact  on 
VAP  of  extending  change  interval  beyond  2  days,  all  ventilated 
patients  in  our  RICU  and  MICU  were  studied  prospectively  over  four 
years  using  the  CDC  criteria  (1988)  to  define  VAP.  In  1991  and  1992 
circuits  were  changed  every  2  days,  followed  bv  7  day  (1993),  and  30 
day  (1994)  change  intervals.  Ventilator  days  did  not  differ  between 
years  (p=0.92).  Adult  ventilators  with  wick  type  humidifers  were 
used  with  standard  circuits  until  heated  wire  circuits  were  added  in 
1994.  Compared  to  2  day  intervals  in  1991-2,  VAP/1000  ventilator 
days  decreased  in  both  RICU  and  MICU  with  both  7  and  30  day  change 
intervals.  In  the  combined  units,  the  difference  in  the  number  of 
ventilator  days  before  patients  developed  VAP  was  not  significant 
between  intervals  (p=0.11).  By  logistic  regression  analysis,  the  odds  of 
developing  VAP  under  the  policy  of  7  day  interval  changes  was 
significantly  less  than  with  the  2  day  interval  changes  (odds  ratio  = 
0.254;p=0.0048).  There  is  some  suggestion  that  there  is  no  difference 
in  risk  of  VAP  between  7  and  30  day  change  intervals.  Extending 
intervals  resulted  in  supplv  and  labor  savings  by  >$20,000. 


■  MICU 

L    ■_     oRiaj  _ 
mm    mm    «23    m™ 


U' 


cr 


07 


Q30 


In  conclusion,  extending  vent  circuit  change  intervals  beyond  2  days 
reduced  the  rate  of  VAP/1000  vent  days  and  appears  to  reduce  the 
likelihood  of  developing  VAP  while  substantially  decreasing  labor 
and  supply  costs. 

OF-95-158 


I  200 


Respiratory  Care  •  November  '95  voi,40  noii 


Tuesday,  December  5,  1:00-2:55  pm  (Rooms  230A-B) 


MOVEMENT  OF  BACTERIAL  CONTAMINANTS  IS  REDUCED  IN 
HEATED  VENTILATOR  CIRCUITS 

R  Orec  BSc,  G  Richards  MB  ChB.  B  Cornere  MNZIMLS,  B  Dove  NZIMLS. 
A  Moms  MB  ChB    Department  of  Microbiology,  Green  Lane  Hospital 
Auckland  New  Zealand 

Introduction    Several  clinical  studies  have  shown  that  the  ventilator  circuits 
of  intubated  patients  rapidly  become  extensively  contaminated  with 
endogenous  bacteria  These  studies  have  all  been  performed  with 
humidified  non  heated  circuits  Bactena  are  known  to  travel  in  circuits  on 
aerosols  created  by  nebulisers  but  there  is  little  information  on  how  bacteria 
move  in  circuits  with  passover  humidifiers,  or  the  effects  of  heater  wires  Aim 
To  determine  the  conditions  required  for  movement  of  bactena  in  modern 
ventilator  circuits  Method  A  typical  ventilator  circuit,  including  a  Siemens 
Servo  900C  ventilator  and  a  Fisher  &  Paykel  MR  730  humidifier  were 
connected  to  a  rubber  "lung"  The  inspiratory  limb  between  the  humidifier 
and  wye  piece  was  comprised  of  four  30  cm  lengths  of  smooth  bore  tubing 
with  connectors  modified  for  bacterial  sampling  The  tubing  was  fixed  at  a  20 
degree  angle  down  from  the  humidifier  to  the  mid  point  then  a  20  degree 
rise  to  the  wye  piece  Dunng  experiments  the  tubing  was  repeatedly 
inoculated  with  a  known  concentration  of  Pseudomonas  aeruginosa  and 
samples  were  taken  regularly  from  other  sites  Two  tests  of  4  hours  duration 
were  performed  with  an  unheated  circuit  and  wye  piece  temperature  of  37 
C,  the  first  with  inoculation  adjacent  to  the  humidifier  and  sampling 
downstream  (  with  the  airflow),  and  the  second  with  inoculation  at  the  wye 
piece  and  sampling  upstream  A  third  test  used  the  same  method  as  test  2 
except  that  a  heated  circuit  was  used  with  the  wye  piece  setting  at  37  C  and 

2  degrees  heating  in  the  circuit  A  forth  test  used  the  same  conditions  as  test 

3  but  was  of  30  hours  duration  Results  Condensate  formed  in  the  tubing  in 
Test  1  and  2  and  bactenal  contamination  followed  the  movement  of  water 
down  to,  but  not  beyond  the  mid  point  in  the  tubing  Bacterial  movement 
could  occur  against  the  airflow  but  not  against  gravity    With  the  heated 
circuit  condensate  was  restricted  to  a  fine  mist  on  the  wall  of  the  tubing  and 
there  was  no  movement  of  water  No  movement  of  bactena  was  noted  over 

4  or  30  hours  Conclusions  In  this  model  movement  of  bacteria  in  a 
ventilator  circuit  only  occurred  if  water  was  present  in  sufficient  amounts  to 
move  within  the  circuit  Using  a  heated  circuit  that  reduced  condensate  to  a 
fine  mist  prevented  movement  of  bactena  Contamination  of  heated  circuits 
is  likely  to  be  less  extensive  than  non  heated  circuits  as  an  important  mode 
of  bactenal  transport  is  eliminated 


OPEN   DISCONNECT  VERSUS  CLOSED  IN-LINE  SUCTIONING 
DURING  HFOV.  Dale  Gerstmann  MO,  Larry  Cooper  RRT.  Ron  Haskill 
RRT,  Gordon  Lassen  RRT  Neonatology  and  Respiratory  Therapy, 
Utah  Valley  Reg  Med  Cen,  Provo,  UT  Introduction:  This  study  com- 
pared the  effects  on  mean  tracheal  airway  pressure  (Prr)  and  real-time 
oxygenation  (PaOij  of  open  circuit  suctioning  (OCS)  versus  closed  cir- 
cuit in-line  suctioning  (CCS)  during  HFOV  Method:  Ten  white  rabbits 
(2  2-2,8  kg)  underwent  sedation,  analgesia,  tracheostomy,  intubation, 
paralysis  and  21  suctioning  episodes  prior  to  and  after  saline  lavage 
(Total  episodes  =  420)  ABGs  were  normalized  by  adjusting  mean  Paw, 
F1O2,  and  pressure  amplitude  (PAmp)  at  a  frequency  (Freq)  of  10Hz. 
Various  ETT  (2,0,  2.5,  3.0mm)  and  catheter  sizes  (5,0,  6.0,  8. OF)  were 
used    Suction  pressure  was  -90  mmHg.  Suctioning  episodes  were  done 
with  random  adjustments  of  Free;  (6,  10,  15  Hz)  and  PAmp  (PAmp-0, 
PAmp+0,  PAmp+WS  cmH20)  along  with  disconnect  suctioning  every  7th 
episode  Pir  was  measured  with  a  small  monitoring  tube  2cm  below  the 
tip  of  the  ETT  Real-time  P3O2  was  measured  with  an  electrode  catheter 
in  the  right  carotid  artery  at  the  level  of  the  aortic  arch.  Each  suction 
episode  was  divided  into  5  segments  based  on  Prr  pre-baseline,  ready, 
suction,  recovery,  and  post-baseline  Segment  interval  time,  Prr,  and 
P3O2  were  measured  and  recorded.  Results:  The  OCS  ready  interval 
was  39%  longer  than  for  CCS  (8.0±0  4  vs  5.8±0.1sec,  p<0  001)  Pit  re- 
covery time  after  suctioning  was  more  with  OCS  (4.2±0.3  vs  2.7±0.1sec, 
p<0.001 )  The  change  in  Prr  during  the  ready  interval  was  greater  with 
OCS  compared  to  CCS  (-75  1±5.4%  vs  -4.4±1.1%,  p<0.001).  Pfrwas  < 
ambient  during  suctioning  except  for  CCS  CATH=5.0  +  ETT=3.0  where 
the  change  was  -57±2%  There  was  no  difference  in  the  change  in  post- 
baseline  Prr  between  OCS  and  CCS  (4  2±0.6%  vs.  0.0±0.3%).  Pa02  de- 
creased more  during  suctioning  with  OCS  than  with  CCS  (-18±2  vs. 
-10±1  torr,  p<0  001)  and  the  change  in  post-baseline  Pa02  was  also 
greater  (-6±2  vs  0±1  torr,  p<0  001 )  Conclusions:  Catheter  introduction 
was  faster  with  CCS  than  with  OCS  CCS  promoted  Pn  maintenance 
during  the  ready  interval,  and  allowed  faster  Pit  recovery  after  suction- 
ing   CCS  lessened  the  drop  in  real-time  Pa02  during  and  after  suction- 
ing. Gas  trapping  or  inadvertent  increases  in  Prr  were  not  seen  with 
OCS  or  CCS  during  any  episode  segment  (Funded  by  a  grant  from  Bal- 
lard Medical  Products,  Draper,  UT.) 

OF-95-229 


EFFECT  OF  VENTILATOR  ADJUSTMENTS   DURING  CLOSED  IN- 
LINE SUCTIONING  WITH  HFOV.  Dale  Gerstmann  MD,  Ron  Haskill 
RRT.  Larry  Cooper  RRT,  Gordon  Lassen  RRT  Neonatology  and  Respi- 
ratory Therapy,  Utah  Valley  Reg  Med  Cen,  Provo,  UT  Introduction: 
We  evaluated  the  effect  of  changes  in  HFOV  frequency  (Freq)  and 
pressure  amplitude  (PAmp)  on  mean  tracheal  airway  pressure  (Prr)  and 
real-time  oxygenation  (PaOi)  during  suctioning  with  closed  in-line 
catheters.  Method:  Ten  white  rabbits  (2.2-2  8  kg)  underwent  sedation, 
analgesia,  tracheostomy,  intubation,  paralysis  and  21  suctioning  epi- 
sodes prior  to  and  after  saline  lavage  (Total  episodes  =  420).  ABGs 
were  normalized  by  adjusting  mean  airway  pressure,  F1O2,  and  PAmp  at 
Freq=10Hz.  Various  ETT  (2.0,  2  5,  3.0mm)  and  catheter  (CATH)  sizes 
(5  0,  6  0,  8, OF)  were  used    Suction  pressures  (Psxn)  of -70,  -90,  -110 
mmHg  were  tested  with  ETT=2.0  +  CATH=5.0,  otherwise  Psxn  =  -90 
mmHg  Suctioning  episodes  were  performed  with  random  adjustments 
of  Freq  (6,  10,  15  Hz)  and  PAmp  (PAmP=0,  PAmp+0,  PAmp+10  cmH20). 
Prr  was  measured  with  a  small  monitoring  tube  2cm  below  the  tip  of  the 
ETT,  Real-time  PaC*2  was  measured  with  an  electrode  catheter  in  the 
right  carotid  artery  at  the  level  of  the  aortic  arch  Each  suction  episode 
was  divided  into  5  segments  based  on  Prr  pre-baseline,  ready,  suction, 
recovery,  and  post-baseline  Segment  interval  time,  Prr,  and  Pa02  were 
measured  and  recorded  Results:  Average  ready,  suction,  recovery 
and  total  interval  durations  were  5  8±0  1 ,  4  3±0. 1 ,  2  7±0  1 ,  and 
13  4±0  2  sees  (meantse)  Ps*n  had  no  effect  as  tested  Lavage  caused 
lower  Pti  in  the  ready  interval  (p=0  003)  and  lower  Pa02  in  the  suction 
interval  (p<0  001 )  Increasing  PAmp  decreased  the  drop  in  Prr  in  the 
ready  interval  (p<0  001 )  and  decreased  the  drop  of  Pa02  during  suc- 
tioning (p=0.018)  and  at  post-baseline  (p<0  001)  Decreasing  Freq  had 
the  same  effect  on  Pa02  during  suctioning  (p<0  001 )  and  at  post- 
baseline  (p<0.001 )  Post-baseline  Prr  was  not  different  from  pre- 
baseline  values,  7.1±0.1  vs  7  1±0.1  cmH20  Conclusions:  Ventilator 
adjustments,  eg  increased  PAmp  and  decreased  Freq,  that  yield  larger 
HFOV  tidal  volume  output  appear  to  retard  drops  in  Prr  before  suction- 
ing (as  the  catheter  enters  the  ETT)  and  preserve  Pa02  during  and  after 
suctioning.  Turning  PAmp  off  appears  less  beneficial  than  leaving  it  on 
or  increasing  it.  Inadvertant  PEEP  (increase  in  Prr)  was  not  seen  in  this 
study  (Funded  by  a  grant  from  Ballard  Medical  Products,  Draper,  UT.) 

OF-95-230 


Christopher  Kramer  Cirrus  Buck  CRNA  RRT,  David  Plevna.  MD,  Dairtll  Schroeder  MS, 
Jeffrey  Want  ME4  RRT 

Department  of  Anesthesiology,  Division  of  Respiratory  Care  and  Section  of  Bioslatistics 
Mayo  Clime  and  Mayo  Foundation,  Rochester.  Minnesota  55905 

INTRODUCTION  Pulse  oximetry  is  an  accurate  and  clinicaljy  useful  method  of  estimating 
arterial  oxygen  saturation   A  significant  fraction  of  the  total  cost  of  applying  this  technology 
results  from  the  use  of  disposable  probes   These  economic  concerns  have  encouraged  the  practice 
of  probe  reckling    However,  oximeter  measurements  made  after  taping  and  recycling  have  not 
been  validated  by  controlled  study    We  undertook  this  investigation  in  order  to  determine  the 
affect  that  taping  and  multiple  recycling  have  on  pulse  oximeter  probe  competence. 
METHODS:  An  Index®  Spoz  simulator  I'Bio-Tek®  InstnrmenU  Inc  )  was  used  at  settings 
designed  to  represent  a  diversity  of  clinical  circumstances  (Table  1 )   Readings  were  made  using  s 
Nellcor  N-1808  oximeter  with  the  individual  probes  attached  to  the  Spc:  simulator 
Approximately  1 5  seconds  were  allowed  before  the  measurements  were  taken.  In  total,  1 00  new 
single-patient  use  Nellcor  D-25*  probes  were  utilized   50  probes  had  3M®  transparent  tape 
(Cat  193)  applied  to  their  fresh,  unused  adhesive  side.  The  remaining  50  probea  did  not  have 
tape  applied.  Readings  were  obtained  before  and  after  application  of  the  tape  in  the  taped  group 
Baseline  readings  were  also  accomplished  in  the  untuned  group    The  probes  were  then  put 
through  20  cycles  of  our  routine  stenliiauon/cleaning  procedure.  These  cycles  consist  of 
ethylene-oxide  sterilization  followed  by  manual  cleaning  with  KJeen-aaeptic®  disinfectant 
Statistical  analysis  included  the  rank  sum  test,  signed  rank  test,  and  Fisher's  exact  test 

Table  1 


Simulator 
Settings 

Criteria 

Spm 

Pulse 

Pulse  Amplitude 

"Normal" 

98% 

60 

100% 

"Weak  Pulae" 

90% 

95 

10% 

"Tachycardia" 

85% 

110 

20% 

RESULTS:  For  all  SO  taped  probei,  baseline  reading*  were  the  nine  before  and  alter  taping 
Baseline  measurements  at  each  of  the  three  Spoi  simulator  aettingi  showed  no  significant 
difference  between  the  taped  and  unlaped  groups   At  all  three  settings,  and  in  both  the  taped  and 
untaped  groups,  no  significant  difference  was  found  between  baseline  readings  and  those  after  20 
cycles   At  the  "normal"  and  "weak  pulse"  settings,  no  significant  difference  was  found  between 
the  accuracy  of  the  readings  in  the  taped  and  untaped  groups  after  20  cycles    However,  at  the 
"tachycardia"  setting,  a  significantly  higher  percentage  of  taped  vs  untaped  probes  obtained  the 
same  measurement  at  baseline  and  after  20  cycles  (96%  vs.  80%,  p- 028) 
CONCLUSION  Pulse  oximeter  probes  may  be  effective  in  estimating  arterial  saturation  after  as 
many  as  20  stenlization/cleaning  cycles    The  application  of  this  transparent  adhesive  tape  does 
not  appear  to  affect  the  accuracy  of  readings  and  may  actually  serve  to  protect  the  probe  from  the 
potentially  damaging  effects  of  recycling    Inaccuracies,  if  and  when  they  do  occur,  may  be  more 
frequent  in  a  cluneal  setting  of  tachycardia  when  tape  u  a  protective  mechanism  has  not  been 
utilized 


Respiratory  Care  •  November  '95  Vol  40  No  1 


1201 


Tuesday.  December  5. 1:00-2:55  pm  (Rooms  230A-B) 


Oj  OPERATING  COSTS  OF  RESUSCITATION  BAGS  IN  THE  NICU  AND  PICU.  Jim 
Kaenan  BS  RRT.  Julie  Ballard  BS  RRT,  and  John  Salyer  BS  RRT.  Primary 
Children's  Medical  Center,  Sail  Lake  City,  UT.  Introduction:  Standby 
resuscitation  bags  are  supplied  lor  all  26  beds  In  the  PICU  and  35  beds  In  the 
NICU  In  the  event  of  any  emergency  that  may  require  supplemental  bagged 
oxygen.  It  has  been  a  standard  practice  at  our  facility  that  flow  meters 
supplying  02  to  these  bags  are  running  at  all  times.  In  our  NICU,  e  blender  is 
always  used  to  power  the  bag,  to  approximate  the  ventilator's  FIO2.  We  sought 
to  determine  the  amount  of  02  wastage  and  Its  cost,  per  Intensive  care  unit. 
Methods:  Fourteen  random  weekdays  of  dala  were  gathered  from  each  unit. 
We  recorded:  1)  flow  rates  of  all  (low  meters  and  2)  blender  usage  (we  use 
the  Sechrist  Air-Oxygen  Mixer,  Model  3500HL,  which  has  a  measured  O2 
bleed  of  approximately  6.5  ipm).  We  also  took  Into  account  the  number  of 
blenders  plugged  In,  with  flow  meter  off,  at  empty  bed  spaces.  We  assumed 
that  the  flow  rates  varied  very  little  throughout  a  24  hr  period  and  that  the 
amount  of  lime  actually  bagging  was  minimal  because  of  the  widespread  use  of 
closed  catheter  suction  systems.  All  dally  flow  rates  and  blender  bleeds  were 
totaled,  then  average  02  daily  costs  were  computed  using  our  cost  of: 
$.533/100  ft3  and  28.3  17100  ft3.  The  mean  cost  of  the  fourteen  days  was 
then  used  to  extrapolate  yearly  totals  for  each  unit.  Results:  Dally  and  yearly 
cost  estimates  are  described  In  figures  1  and  2. 
tiso 

11"" 

13 


liuii 


PCU 

$30 

110,769 

NCU 

S68 

524.882 

FACUTY 

$ge 

135.651 

Cwy 

Figure  one:  Dally  estimated  02  wastage  Figure  two:  Dally  and  yearly 

costs  over  14  days.  o2  wastage  costs 

Discussion:  We  feel  that  wastage  costs  of  supplying  standby  02  In  both 
Intensive  care  areas  are  financially  significant.  This  study  reveals  that  the  use 
of  blenders  with  bleeds,  as  in  our  NICU,  greatly  Increases  these  costs.  Habits 
of  practice  will  often  dictate  whether  these  resuscitation  bags  can  and  should 
be  turned  off  when  not  In  use.  Even  If  the  practice  of  turning  off  the  flow 
meters  Is  adopted,  the  bleed  factor  on  the  blenders  Is  still  a  problem.  Many 
clinicians  will  argue  that  clinical  safety  outweighs  the  cost.  There  are 
automatic  shut  off  devices  and  blenders  with  little  or  no  bleed  available.  The 
capital  cost  of  these  products  have  limited  their  widespread  use.  Further 
studies  need  to  be  performed  on  these  cost  saving  devices,  to  determine  If  the 
cost  to  savings  ratio  will  minimize  the  cost  of  operating  resuscitation  bags. 

OF-95-210 


William  T.  Peruzzi,  MD;  Suellen  G.  Moen,  BSN;  Mary  Weinert,  MD; 
Lance  Peterson,  MD;  Brian  L.  Smith,  RRT;  Robert  Hirschtick,  MD. 
Northwestern  University,  Chicago,  Illinois 

Information  was  collected  to  determine  the  number  of  induced 
sputum  samples  necessary  for  definitive  diagnosis  of  Pneumocystis  carinii 
pneumonia  (PCP). 

Over  a  5  month  period,  sputum  inductions  were  monitored  and 
data  collected  on  all  patients  being  evaluated  for  PCP  in  a  large 
university  hospital  and  AIDS  treatment  center.  The  diagnostic  protocol 
required  three  sequential  inductions  followed  by  individual  direct 
fluorescent  antibody  (DFA)  stains  (Genetic  Systems™,  Seattle,  WA)  on 
each  sample.  Once  twenty  patients  tested  positive  for  PCP,  the  study  was 
concluded, 

A  total  of  92  patients  (102  admissions)  were  evaluated.  Thirty 
seven  (36%)  of  the  admitting  diagnoses  were  presumed  PCP,  26  (26%) 
were  pneumonia,  and  the  remaining  39  (38%)  admissions  had  diagnoses 
not  related  to  PCP  or  pneumonia.  A  total  of  297  sputum  inductions  were 
performed.  Fifty  seven  (19%)  of  the  inductions  did  not  result  in 
adequate  sputum  samples  due  to  collection  errors,  patient  refusal  of  the 
induction  procedure,  nonproductive  inductions,  or  the  quantity  was  not 
sufficient.  When  appropriate  samples  were  obtained,  193  (65%)  were 
negative  for  PCP  and  47  (16%)  were  positive.  Of  the  20  patients  positive 
for  PCP,  19  were  positive  on  the  first  adequate  sputum  sample;  only  1 
tested  negative  on  the  first  adequate  sample  and  was  positive  on  the 
second  sample.  Three  patients  had  an  initial  positive  result  followed  by 
negative  results  after  approximately  3545  hours  of  antimicrobial  therapy. 

Our  data  support  that  one  sputum  induction  is  sufficient  to 
definitively  determine  whether  the  patient  is  positive  or  negative  for 
PCP.  If  the  first  technically  adequate  sputum  induction  is  negative, 
bronchoscopy  should  be  the  next  step  in  evaluation  if  the  diagnosis  of 
PCP  is  still  in  question. 


AARC  Clinical  Practice  Guidelines 


CPG  1  —Spirometry  •  $1 

CPG  2  —  Oxygen  Therapy  in  Acute  Care  Hospital  •  $1 

CPG  3  —  Nasotracheal  Suctioning  •  $1 

CPG  4  —  Patient- Ventilator  System  Checks  •  $1 

CPG  5  —  Directed  Cough  •  $1 

CPG  6  —  In-Vitro  pH  and  Blood  Gas  Analysis  and  Hemoximetry  • 

CPG  7  —  Use  of  Positive  Airway  Pressure  Adjuncts  to  Bronchial 

Hygiene  Therapy  •  $1 
CPG  8  —  Sampling  for  Arterial  Blood  Gas  Analysis  •  $1 
CPG  9  —  Endotracheal  Suctioning  of  Mechanically  Ventilated  Adult 

and  Children  with  Artificial  Airways  •  $1 
CPG  10  —  Incentive  Spirometry  •  $1 
CPG  11  —  Postural  Drainage  Therapy  •  $1 
CPG  12  —  Bronchial  Provocation  •  $1 
CPG13  —  Selection  of  Aerosol  Delivery  Device  •  $1 
CPG14  —  Pulse  Oximetry  •  $1 

CPG15  —  Single-Breath  Carbon  Monoxide  Diffusing  Capacity  •  $1 
CPG16  —  Oxygen  Therapy  in  the  Home  or  Extended  Care  Facility  • 
CPG17  —  Exercise  Testing  for  Evaluation  of  Hypoxemia 

and/or  Desaturation  •  $1 
CPG18  —  Humidification  during  Mechanical  Ventilation  •  $1 
CPG19  —  Transport  of  the  Mechanically  Ventilated  Patient  •  $1 
CPG20  —  Resuscitation  in  Acute  Care  Hospitals  •  $1 
CPG21  —  Bland  Aerosol  Administration  •  $1 
CPG22  —  Fiberoptic  Bronchoscopy  Assisting  •  $1 
CPG23  —  Intermittent  Positive  Pressure  Breathing  (IPPB)  •  $1 

Texai  Ctiitomcrt  only, pUaie  add  A '21%  lalei  lax  (mdudiig  ihippmjt  (/'.irgril  Texal  imlo 


CPG24  —  Application  of  CPAP  to  Neonates  Via  Nasal  Prongs  or 

Nasopharyngeal  Tube  •  $1 
CPG25  —  Delivery  of  Aerosols  to  the  Upper  Airway  •  $1 
CPG26  —  Neonatal  Time-Triggered,  Pressure-Limited,  Time-Cycled 

Mechanical  Ventilation  •  $1 
CPG27  —  Static  Lung  Volumes  •  $1 
CPG28  —  Surfactant  Replacement  Therapy  •  $1 
CPG29  —  Ventilator  Circuit  Changes  •  $1 
CPG30  —  Metabolic  Measurement  using  Indirect  Calorimetry 

during  Mechanical  Ventilation  •  $1 
CPG31  —  Transcutaneous  Blood  Gas  Monitoring  for 

Neonatal  &  Pediatric  Patients  •  $1 
CPG32  —  Body  Plethysmography  •  $1 
CPG33  —  Capillary  Blood  Gas  Sampling  for  Neonatal  & 

Pediatric  Patients  •  $1 
CPG34  —  Defibrillation  during  Resuscitation  •  $1 
CPG35  —  Infant/Toddler  Pulmonary  Function  Tests  •  $1 
CPG36  —  Management  of  Airway  Emergencies  •  $1 

CPG99  —  Complete  Set  in  Binder  •  $25 

(+$3.25  for  Shipping  and  Handling) 

American  Association  for  Respiratory  Care 

11030  Abies  Ln.  •  Dallas,  TX  75229-4593 

Call  (214)  243-2272  or  fax  to  (214)  484-2720 

with  MasterCard,  Visa,  or  Purchase  Order  Number 


1202 


RESPIRATORY  CARE  •  NOVEMBER  '95  VOL  40  NO  1 1 


Quick. 
What'**  the  name  of  thu  piece  of  equipment? 

If  you  said  an  "ambubag",  think  again.  It's  a  manual  resuscitator.  And  for  over  30  years, 

Laerdal  Resuscitators  have  been  the  popular  choice  of  Respiratory  Care  Departments 
m   and  EMS  professionals.  Why?  Because  Laerdal  Resuscitators  offer  superior 
performance  and  outstanding  safety  features.  They're  available  in  adult,  child 
and  infant  sizes  -  with  numerous  configurations.  Best  of  all,  they  can  be 
reprocessed  over,  and  over  and. .  .over  again. 

A  resuscitator  by  any  other  name  is  not  a  Laerdal. 

For  more  information,  call  800  431-1055  for  the  Laerdal  Silicone  Resuscitator  InfoFax. 


Visit  Laerdal  at  Booth  651  at  the 
American  Association  for  Respiratory  Care, 
December  2-5,  1995,  Orlando,  Florida. 

Circle  140  on  reader  service  card 


Laerdal 

helping  save  lives 


Laerdal  Medical  Corporation  •  167  Myers  Corners  Road  •  Wappingers  Falls,  NY  12590  •  800  431-1055  •  914  297-7770 


Tuesday,  December  5,  1:00-2:55  pm  (Rooms  230C-D) 


Richard  Q.  Hmn«nn.  R.R.T..  Kennsth  0«vis,  Jr.,  M.D..  Jay  A.  Johannigman,  M.D.. 
Division  of  Trauma  and  Critical  Cars.  Department  of  Surgery,  University  of 
Cincinnati  Medical  Canter,  Cincinnati,  Ohio 

INTRODUCTION:    Pressure  support  ventilation  (PSV)  has  become  a  popular  method 
of  ventilatory  support  dunng  weaning.   We  compared  the  PSV  functions  of  two 
ventilators  duhng  simulated  spontaneous  breathing.   METHODS:   We  simulated 
spontaneous  breathing  (SSB)  using  a  two-chambered  test  lung  at  three  tidal  volume 
and  flow  combinations  1200  mL  at  30  l  mm.  400  mL  at  60  L  mm,  and  600  mL  at 
90  l  mini  and  at  0  and  5  cm  PEEP.    During  SSB  we  connected  the  2  ventilators 
(Bird  TBJrd  VS  and  Puritan-Bennett  7200ael  to  the  expenmentai  chamber  in  the 
PSV  moda  at  1 5  cm  H,0.    A  pneumotachograph  and  pressure  tsp  were  placed  at 
the  proximal  airway  and  measurements  of  pressure,  volume,  and  flow  were 
recorded  to  a  parsons!  computer  using  a  data  acquisition  system  (Keithley  DAS 
16).    From  thesa  signals  the  WOB,,  maximum  negative  pressure  iPmax),  delay  time 
■  DTi,  and  pressure  time  product  (PTP)  were  calculated.  Wa  also  calculated  rise 
time  i the  time  in  seconds  to  reach  90%  of  the  sat  pressure!  and  overshoot  (the 
difference  between  actual  peak  pressure  and  set  pressure).    RESULTS:    The  WO B., 
PTP,  Pmsx,  end  delay  time  were  alt  significantly  less  with  the  TBird  VS  compared 
to  the  7200m  (p<0.05).    Overshoot  was  significantly  lass  in  sll  situations.   Rlsa 
time  was  faster  with  the  TBird  VS,  except  at  the  600  mL  and  90  L/min  inspiratory 
flow.    Table  1  shows  data  from  SSB  at  400  mL  and  60  L/mln. 


Variable 

TBird  VS 

7200ae 

Delay  Time  (si 

0.09  10.021* 

0.12  10.02) 

Pmax  Icm  H,0) 

1.0  10.2)0 

3.6  10.51 

WOBJ/U 

0.004  10.001)* 

0.020  10.0061 

PTP  lcmH,0/sl 

0.03  (0.0141* 

0.15  I0.03I 

Rlu  Time  Is) 

0.21  10.0061* 

0.34  [0.011 

Overshoot  Icm  H,0) 

0.57  10.08)* 

0.92  10.041 

Pmax  -  maximum  negative  pressure;  WOB  -  work  of  breathing;  and  PTP*  - 
pressure  time  product.   *p<0.05  vs  7200ae. 

CONCLUSIONS:  Our  results  suggest  that  the  TBird  VS  allows  a  lower  WOB,  and 
tighter  control  of  set  pressure  support  level  compared  to  the  7200ae.   The 
differencee  in  these  velues  is  small  and  the  clinical  importance  ia  uncteer. 


EFFECTS  OF  CHANGES  IN  rNSPIRATORY  RISE  TIME  ON  IMPOSED  WORK  OF 
BREATHING  IN  A  PEDIATRIC  ANIMAL  MODEL 
Mark  J.  Hculrtt,  M  D ,  Shirley  Holt.  RRT.  Sterling  Wilson  MS 
Critical  Care  Medicine  and  Respiratory  Care  Services,  Arkansas  Children's  Hospital, 
Little  Rock,  AR. 

INTRODUCTION:  The  new  generation  of  ventilators  allows  clinician  control  of  the 
inspiratory  rise  time  (IRT)  The  IRT  controls  the  initial  flow  rate  of  the  ventilator  breath 
and  can  be  adjusted  between  0%  and  10%  on  the  Siemens'  Servo  300™.  It  has  been 
shown  in  adults  that  shorter  inspiratory  rise  times  decreased  work  of  breathing  (WOB), 
but  it  has  been  speculated  that  in  patients  with  smaller  endotracheal  tubes,  shorter  rise 
times  may  increase  WOB    METHODS:  We  performed  a  prospective  randomized 
controlled  cross  over  study  in  3  young  lambs.  Lambs  were  randomized  to  either  IRT  1% 
or  IRT  10%  with  pressure  support  of  5  cm  H,0.  During  each  IRT  trial,  the  animal  was 
studied  with  and  without  an  externally  placed  resistor  (-R)  that  reduced  the  size  of  the 
endotracheal  tube  lumen.  Each  animal  was  used  as  its  own  control  and  studied  on  at 
least  8  separate  days  with  both  IRTs    WOB  was  measured  with  a  Bicore™  monitoring 
device  as  WOB  of  the  animal  (WOBp) ,  pressure  time  product  (PTP),  peak  inspiratory 
flow  rate  (PIFR),  esophageal  pressure  (DPES),  and  expiratory  resistance  (RAWE)  for 
each  breath  during  the  experiment.  A  Wilcoxon  signed  rank  sum  test  was  utilized  for 
statistical  analysis. 
RESULTS: 


IRT  1% 
(SD) 

IRT  10% 
(SD) 

P 

IRT  1%+R 
(SD) 

IRT  10%+R 
(SD) 

P 

WOBp  (J/L) 

0 23+0  54 

0.36+0.58 

O.001 

0.44+0,58 

0  57+0  59 

<0  001 

Pes  (cm  H.0) 

4.2+3.2 

5.9+4.4 

<0  001 

6.4+5.2 

8  6+7  9 

<0.001 

PTP  (cm 

H.Osrrun-1) 

62.6+58 

86.5+74 

<0.001 

87.7+82 

126+94 

<0.001 

PIFR  (L/min) 

0.36+0.12 

0.33+0.11 

<0.001 

0.28+0.09 

0  27+0  07 

<0  001 

RAWE  (cm 
HjO/Us) 

21.9+4.4 

21.9+4.8 

NS 

44,6+4,1 

43.3+6.8 

NS 

CONCLUSIONS:  WOB  is  lower  in  animals  supported  with  pressure  support  when  IRT 
1%  is  compared  to  IRT  10%.  This  difference  is  maintained  when  resistance  is  increased. 
We  speculate  that  in  pediatric  patients  with  small  endotracheal  tubes  and  increased 
WOB,  utilizing  shorter  IRT  may  reduce  WOB 


RESPONSE  TIKES  Of  PEDIATRIC/NEONATAL  PRESSURE-SUPPORT 
vmTTI.ATORB-P.ul  Holbraok,  CRTT I  Stan  Guiles,  RRT.  Children 
Hospital  £  Health  Center,  San  Diego  CA .  Hany  infante  and 
neonates  can  only  generate  very  email  inspiratory  efforts, 
object  of  this  stud 
infant/pedietric  ventilators  to  weak  Inspiratory  efforts  at 
various  pressure  support  (PSV)  levels.  METHODS:  A  Newport  E100 
was  used  to  drive  one  compartment  of  a  Michigan  TTL,  set 
to  generate  peak  inspiratory  flowratee  of  2LPM ( neonatal  effort) 
and  5LPM(pediatric  effort)  in  the  dependent  compartment.  A 
two-channel  recorder  allowed  almultaneous  comparison  of  preesur 
changes,  which  were  monitored  at  the  proximal  preesure  ports  of 


All 


Ella 


Lung  model 


1  infant,  1  pediatric 

and  5  mm  ETT.  Compliance  waa  set 
and  3mL/cmH20  (4,  S  ETT).  Reapona 


aa  connected 
lmL/cm  H20 
(2.5,  3.5  ETT) 

dsftned  as  the  interval  between  pressure  rise  in  the  drive 
compartment  and  the  return  to  baaeline  from  a  negative 
deflection  in  the  dependent  compartment.  The  Siemens  SV300, 
Newport  E200,  and  Bird  VIP  ware  tested  at  PSV  levels  of  3,  10, 
20cm  H20  at  CPAP  of  3cmH20.  Sensitivity  was 
ventilator  while  avoiding  auto-trigger  phen< 
Aggregate  data  are  presented  for  each  ETT  a 
aa  mean(SD). 

NEWPORT  E200 


xLmlxed  in  each 
na.  RESULTS i 
in  milliseconds 


2.5  ETT 
3.5  ETT 
4.0  ETT 
5.0  ETT 


SIEMENS  SV300 
64.45  (4. 25) 
B7.75  (9.22) 
85.39  (13.33) 
92.65  (22.81) 
of  Tr  ha 


49.43 
63.17 
68.53 

85.13 


(3.72) 
(11.06) 
(11.32) 
(23.45) 


various  defln 

significantly  different  than  o 

ANESTHESIOLOGY  1989 ] 7 1 1  977-81 

1993;38il253).  Including  a  ret 
definition  of  Tr,  and  attachma 
indicative  of  a  ventilator'a  r 
VIP  Inconsistently  triggered  b 
teating.  SV300  perfo 


BIRD  VIP 
147.43  (4.7S) 
126.77  (1.62) 
138.7  (9.66) 
146.48  (8.17) 
r  as  used  here  waa 
d  data  (Martin  et  al 
RESP.  CARE 


ally 


of  a  lung  model  is 
oneivenees  to  pati 
the  during  2.5,  3. 
5  ETT  was  best  in 
A   more  quickly  the 


EVALUATION  OP  THREE  ADULT  PRESSURE-SUPPORT  VENTILATOR  RESPONSE 

TIKES-Paul  Holbrook.  CRTT.  Children's  Hospital  and  Health 
Center,  San  Diego;  Snarl  Ropelato,  RRT,  Hoag  Memorial  Hoepital, 
Newport  Beach  CA;   Jeff  Child,  RRT,  McKay-Dee  Hoepital  and 
Medical  center,  ogden,  UT.  We  poatulated  that  appropriately 
applied  presaure  triggering  could  be  aa  responsive  to  patient 
effort  as  flow  triggering.  To  teet  this  theory,  we  evaluated  the 
reaponsivenese  of  throe  adult  critical  care  ventilators  to  a 
relatively  weak  inspiratory  effort.  METHODS t  Response  time  (Tr) 
for  our  purposes  was  defined  as  the  interval  between  preaaura 
rise  in  the  drive  compartment  and  the  return  to  baaeline 
preesure  from  a  negative  deflection  in  the  dependent  compartment 
of  a  two-elded  Michigan  Inatrumenta  test  lung.  A  Newport  E100 
connected  to  the  drive  compartment  waa  act  to  generate  a  peak 
inepiratory  flow  of  25  LPM  in  the  dependent  lung  to  eimulate 
weak  adult  efforts.  A  dual-channel  recorder  allowed  comparison 
of  eimultaneous  pressure  signala  at  the  proximal  pressure  port 
of  each  ventilator  circuit.  The  same  adult  circuit  was  used  to 
test  all  ventilatora.  Compliance  of  dependent  compartment  was 
set  to  55  mL/cmH20.  Lung  model  was  then  connected  to  6mm  and  8.S 
mm  ETT.   The  Puritan-Bennett  7200,  slemena  SV300,  and  Newport 
E200  were  tested  at  pressure  support  levels  (PSV)  of  3,  10,  and 
20  cmH20  at  CPAP  of  5  cmH20.  The  7200  was  teeted  in  both 
preeeure(PT)  and  flow(FT)  triggering.  Sensitivity  waa  maximized 
in  each  ventilator  while  avoiding  auto-trigger  problems.  7200FT 
waa  teeted  at  flow-by  of  5LPH,  sensitivity  of  -1LPM.  results. 


99.5  (4.2) 
118.6(6.7) 
63.4  (7.0) 


each  ETT  els 
720orr 

115.9(7.86) 
114.0(1.35) 
117.5(7.52) 


and  PSV  level 

SV300 
68.0(3.35) 
75.1(2.32) 
90.9(3.17) 


an(SD). 
1200 
44.1(1.95) 
45.9(2.03) 
42.8  (2.0) 


The  E200 


better  at 


75.5(11.1)  129.9  (7.3) 
64.3(7.74)  124.6(1.24) 
75.1(5.69)  93.6  (4.  9) 
ind  the  7200  performed  bei 
beat  at  PSV  of  10  cmH20. 
PSV  greater  than  3  cmH20. 


97.6(3.76) 
69.0(0.61) 
80. 2(1. 71) 
t  at  PSV  of  20  cmH20. 
Qenerally,  performanc 
7200PT  performed  bet 


44.2(2.76) 
45.9(2.03) 
41.9(6.42) 

SV300 


7200FT.  CONCLUSION! 


'1'OOP 


dlffe 
perfo 


aonaitivity,  although  these  findings  do  indicste 
further  etudy.  Continuously  adjustsble  presaure  t 
coupled  with  proximal  preeeure  monitoring  minimiz 


1204 


Respiratory  Care  •  November  '95  Vol  40  No  11 


Tuesday,  December  5,  1:00-2:55  pm  (Rooms  230C-D) 


FLOW  VERSUS  PRESSURE  TRIGGERING  IN  MECHANICALLY  VENTILATED 
ADULT  PATIENTS. 

Robert  L  Gould  MS.  RRT.  Dean  Hess,  PhD,  RRT,  Robert  M.  Kacmarek,  PhD,  RRT. 
Respiratory  Care  and  Anesthesia,  Massachusetts  General  Hospital  and  Harvard  Medical 
School,  Boston,  MA. 

Adult  mechanical  ventilators  have  traditionally  been  pressure  or  time  triggered.  More 
recently,  flow  triggering  has  become  available  with  adult  ventilators  and  some  ventilators 
allow  the  choice  between  pressure  or  flow  triggering.  Although  bench  studies  have  supported 
the  superiority  of  flow  triggering,  there  have  been  few  studies  that  compared  pressure  and  flow 
triggering  in  patients.  The  purpose  of  this  study  was  to  compare  pressure  and  flow  triggering 
during  pressure  support  ventilation  (PSV)  in  adult  mechanically  ventilated  patients    Method: 
The  study  population  consisted  of  10  adult  patients  ventilated  with  a  Puritan- Bennett  7200  in 
PSV  mode  (6  males  and  4  females,  age  62.9 ±  17.1  y,  PSV  12.1  ±  5.7  cm  H50,  PEEP  5.1  ±  I.I 
cm  H30)    We  compared  4  trigger  settings  in  random  order:  pressure  trigger  of -1  cm  H30  and 
-0.5  cm  H,0,  flow  trigger  of  10/3  L/min  and  5/2  L> 
VenTrak  Respiratory  Monitoring  System  CNovamc 
acquisition  rate  of  100  Hz.  Pressure  calibration  wa 
water  column    Pressure  was  measured  at  the  proxi 
setting.  10  representative  breaths  that  were  free  of  i 

points  at  100  Hz  were  exported  to  a  spreadsheet  (Microsoft  Excel)  for  detailed  anal; 
airway  pressure  wave  form.  From  the  airway  pressure  signal,  trigger  pressure  (AP)  was 
defined  as  the  difference  between  PEEP  and  the  maximum  negative  deflection  prior  to  onset 
the  triggered  breath.  Trigger  time  (AT)  was  defined  as  the  interval  between  the  initial  negat 
deflection  and  the  onset  of  the  triggered  breath.  Pressure-time  product  (PTP)  was  defined  a< 
the  area  produced  by  the  pressure  waveform  below  PEEP  from  initial  negative  deflection  un 
the  onset  of  the  triggered  breath.  Statistical  analysis  consisted  of  mean  ±  SD  and  ANOVA 
with  post-hoc  ScheffC  test    Results: 


min.  Data  were  collected  for  5  min  using  a 
rrix,  Wallingford,  CT)  with  a  data 
s  performed  at  0  and  1 0  cm  H:0  using  a 
rial  endotracheal  tube.  At  each  trigger 
irtifact  were  chosen  for  analysis.  Raw  data 
of  the 


trigger 

AP(cmH,0) 

AT  (ms) 

PTP  (cm  HjO  ■  !) 

pressure  -  0.5  c 

TiH:0 

1.1  ±0.4 

172.9  ±60.3 

0.088  ±0  039 

pressure  -1.0c 

■nH.O 

16  ±  0  5 

196.9  ±50.5 

0.140±0041 

How-  10/3 

1.4  ±0.7 

186.9  ±50.8 

0.137  ±0.073 

flow  •  5/2 

1.3  ±0.7 

1806=424 

0.199  ±0.054 

Pressure  trigger  of  0.5  cm  HjO  was  significantly  less  than  the  other  trigger  methods  (P  <  0.01) 
for  AP,  AT.  and  PTP;  flow  trigger  of  10/3  L/min  was  not  significantly  different  than  flow 
trigger  of  5/2  L/min  or  pressure  trigger  of  1  cm  HjO.  There  were  also  significant  differences 
between  patients  for  AP,  AT,  and  PTP  for  each  trigger  method  (P  <  0.00 1 ).  Concluiiom:  For 
this  group  of  patients,  flow  triggering  was  not  superior  to  pressure  triggering  at  -0.5  cm  H,0. 
It  is  of  interest  to  note  that  prior  studies  comparing  pressure  and  flow  triggering  have  typically 
used  a  pressure  trigger  of  1 .0  cm  HjO.  The  significant  differences  that  we  found  between 
patients  suggests  that  respiratory  drive  may  have  an  important  effect  on  triggering, 
(Supported  in  part  by  Puritan- Bennett  Corporation) 

OF-95-097 


THE  EFFECTS  OF  AIRWAY  LEAK  ON  TIDAL  VOLUME  DURING  PRESSURE  OR 
FLOW  CONTROLLED  VENTILATION  OF  THE  NEONATE:  A  MODEL  STUDY 

Robert  L.  Chatbum  RRT,  Teresa  Volsko  RRT.  Rainbow  Babies  &  Childrens  Hospital  Cleveland, 
OH,  St.  Elizabeth's  Hospital  Medical  Center,  Youngstown.  OH. 

Leaks  associated  with  uncuffed  endotracheal  tubes  complicate  mechanical  ventilation  of  the 
neonate.  The  variable  nature  of  leaks  and  the  possibility  of  different  modes  of  ventilation  suggest 
an  optimal  strategy  for  stability  of  tidal  volume.  The  purpose  of  this  study  was  to  evaluate  the 
effect  of  leak  on  tidal  volume  during  pressure  or  flow  controlled  ventilation  (PCV  or  FCV). 
METHOD:  We  used  a  lung  model  consisting  of  an  elastic  bellows  (compliance  =  1  mL/cm 
H20)  attached  to  a  3.0  ET  tube  with  a  3-way  stopcock.  One  port  of  the  stopcock  was  attached  lo 
a  fixed  orifice  leak  (%  leak  =  19-34  %  depending  on  ventilator  settings).  A  Newport  Wave  venti- 
lator in  SIMV  mode  generated  either  constant  inspiratory  pressure  (PCV)  or  constant  inspiratory 
flow  (FCV)  at  the  same  tidal  volume.  Inspired  and  expired  volumes  were  measured  with  a 
BICORE  CP-100  Neonatal  monitor.  Calibration  was  verified  with  a  100  mL  syringe.  The  effect 
of  leak  on  exhaled  tidal  volume  (VE)  was  defined  as: 

%AVE=V£(leakof°-VE(leakQn)xl00 


Vb( 


<off) 


Large  (-15  mL)  and  small  0*7  mL)  tidal  volumes  were  used  along  with  long  (0.8  s)  and  short 
(0.3  s)  inspiratory  times.  Each  combination  was  repeated  twice  (n=3).  Differences  in  %VE  wen 


FCV 

PCV 

:     I 

p.  0  002  - 

: 

i    j 

FCV 


PCV 


FCV 


PCV 


The  effect  of  leak  was  generally  less  wiUl  PCV  because  it  generated  a  larger  mean  inspiratory 
pressure.  CONCLUSION:  An  optimum  strategy  for  dealing  with  intermittent  airway  leaks  might 
be  short  inspiratory  times  and  relatively  large  tidal  volumes  independent  of  mode.  At  small  tidal 
volumes  and  long  inspiratory  times,  vcntilauon  should  be  more  stable  wiul  PCV. 

OF-95-078 


ALTERING  FLOW  RATE  DURING  PRESSURE  SUPPORT  VENTILA- 
TION: EFFECTS  ON  WORK  OF  BREATHING  AND  RESPIRATORY 
DRIVE. 

Massimo  Croci  MP.  Paolo  Pelosi  MD,  Davide  Chiumello 
MD,  Luciano  Gattinoni  MD 

Inst,  of  Anesthesia  and  Intensive  Care,  University  of 
Milan,  Ospedale  Maggiore  IRCCS,  Milan,  Italy. 

Pressure  support  delivered  by  various  mechanical 
ventilators  is  characterized  by  a  non  adjustable, 
rapide  rise  to  a  selected  pressure.  A  new  ventilator 
(Bear  1000)  allows  an  adjustable  pressurization  rate 
(PR),  resulting  in  a  variable  peak  inspiratory  flow 
(PIF)  during  pressure  support  ventilation  (PSV).   Aim 
of  this  study  was  to  evaluate  the  usefulness  of 
variable  pressurization  rate  in  reducing  work  of 
breathing  and  respiratory  drive  during  PSV. 
METHODS  We  studied  7  stable  patients,  during  weaning 
phase  with  PSV  (PEEP  4.3±2  cm  H,0,  PS  912  cm  H20, 
Ft02  0.4510.1).  Measuring  gas  flow,  airway  and  eso- 
phageal pressures  we  computed  PIF,  work  of  breathing 
per  minute  (WOB/min)  and  per  liter  of  ventilation 
(WOB/1),  and  respiratory  drive  (P0.1).  Measurements 
were  obtained  at  PS  of  5  and  15  cm  H20  with  highest, 
lowest  and  optimal  PR.  Optimal  PR  was  defined  as  that 
resulting  in  minimum  WOB/min. 
RESULTS  Data  are  expressed  as  mean  1  S.D. 


PS  5  cm  H20  Lowest 
PIF(1/S)    0.4410.11 
WOB/l(J/l)     211 
P0.1(cm  H20)   412.6 


PS  IS  cm  H20 

PIF(1/S)    0.4610 
WOB/l(J/l)     110.6 
P0.1(cm  H20)3.312.3 


09 


Highest 

0.6210.07 

0.810.4 

2.111.2 


1.811. 1 


Optimal 

0.6110.09 

0.810.4 

2.211.5 


D. 7910. 17 
0.110.1 
2.410.8 


ANOVA:  *p<0.01  compared  to  Lowest  PR,  $p<0.05  compa- 
red to  highest  PR,  #p<0.01  compared  to  highest  PR. 
CONCLUSION  We  conclude  that  the  possibility  to  adjust 
PR,  and  hence  PIF,  during  PSV  is  an  useful  tool  to 
improve  patient-ventilator  synchrony  at  different 
levels  of  pressure  support. 

OF-95-082 


EFFECT  OF  VARIATIONS  IN  SOURCE  GAS  PRESSURE  ON  OBSERVED  FLOW 
OUTPUT  OF  TWO  TRANSPORT  VENTILATORS   Kelvin  Mac  Donald,  RCP, 
CRTT..  Peter  Wano.  RCP,  RRT „  Wei  Cowan,  RCP,  RRT.   Kaiser  Permanente 
Medical  Center,  Los  Angeles. 

INTRODUCTION:  Transport  ventilators  by  their  very  nature,  may  encounter 
variations  in  source  or  wall  gas  pressures  used  as  internal  working  pressure.  Many 
designs,  including  the  ones  tested  rely  on  an  inspiration  solenoid,  operating  al 
working  pressure  to  generate  flow.  During  a  mechanical  breath,  these  solenoids 
allow  gas  at  the  set  inspiratory  time  to  travel  through  a  flow  control  and  on  to  the 
patient.  We  sought  to  determine  what ,  If  any  effect  varying  source  gas  pressure 
has  on  observed  flow  output  during  a  mechanical  breath.  METHODS:  Two 
Impact  Medical.  UniVent  750  (West  Caefwell,  NJ),  and  two  Bird  Medical,  Avian 
(Palm  Springs,  CA)  transport  ventilators  were  used.  These  were  in  turn  connected 
via  a  Professional  Medical  Devices  5400  disposable  ventilator  circuit  to  an 
Ohmeda  Lung  Simulator  (C  =  10  ml/cm  H20,  Resistance  =  5  cm  H20/L/sec). 
Flow  output  was  measured  using  a  Timeter  RT-200  Calibration  analyzer.  Source 
gas  pressure  was  controlled  with  a  Western  Enterprises  single  stage  pressure 

regulator.  Each  ventilator  was  tested  at 
Inspiratory  Tims  (•)      Flow  rate  (Lpm)       30,  40,  50,  60,  and  70  PSIG.  Each 

0.5                        40               ventilator  was  sat  as  shown  in  the  labia. 

07                        SO               p|OW  ral6  output  and  tidal  volume  were 
1                          5°               record  at  each  setting  and  PSIG 
,s                        JS,              combination.  The  ventilator's  mean  flow 
output  @  each  PSIG  level  was  compared 
to  itself  ®  50  PSIG  as  a  control.  Mean  flow  output  between  the  two  type  was 
compared  @  50  PSIG  to  validate  controls.  RESULTS:  The  mean  difference  In 
observed  flow  output  between  the  two  types  ®  50  PSIG  was  2.1%  (S.D.  3.3%).  A 
correlation  coefficient  of  .995  with  a  covenant  of  0.13  was  calculated.  The 
mean  %  difference  (SD)  from  each  ventilator's  control  maen  flow  output,  at  each 
pressure  level  for  each  ventilator  are  shown  in  the  table. 

Source  PSIG 

Avian 

Uni-Vent 

We  also  observed  a 
proportionally  corresponding 
decrease  in  delivered  tidal 
volume  with  each  decrease  \n 
observed  flow  output.  The 
negative  mean  percent 
utput.  DISCUSSION:  The  AVIAN 
sduces  ventilator  working  pressure 
rcent  difference  observed  flow 
or  also  prevented  increased  flow 
he  Uno-vent.  CONCLUSIONS: 
ventilator  types  @  50  PSIG,  flow 
at  other  than  50  PSIG.  This  may 
lulator  and  gauge  and  realizing 
ressures. 

OF-95-219 

30 

14  %  (3%) 

46%  (3%) 

40 

4%  (2.5%) 

30%  (3.5%) 

60 

0  5%  (1  5%) 

-14%  (2%) 

70 

1.5%  (15%) 

-29%  (7  5%) 

differences  reflect  increases  in  observed  flow  c 
features  an  internal  pressure  regulator,  which  r 
below  50  PSIG  This  accounts  for  the  lower  pi 
output  with  a  low  source  pressure  This  regula 
output  with  high  source  pressure  as  seen  with 
While  there  was  good  agreement  between  bot 
output  variation  was  greater  with  the  Unl-Vent 
be  alleviated  by  using  an  external  pressure  ret 
flow  output  will  decrease  with  low  source  gas  p 

Respiratory  Care  •  November  '95  Vol  40  No  11 


1205 


Tuesday,  December  5, 1:00-2:55  pm  (Rooms  230C-D) 


,  University 
Italy. 


PRESSURIZATION  RATE  REGULATION  MAY  REDUCE  INSPIRATORY 

EFFORT  DURING  PRESSURE  SUPPORT  VENTILATION  (an  "in 

vitro"  study) . 

Massimo  Croci  MP.  Paolo  Pelosi  MD,  Lucia  Negroni  MD, 

Alba  Norsa  MD ,  Gabriella  Toniolo  MD,  Patrizia  Andreo- 

ni  MD,  Luciano  Gattinoni  MD 

Inst,  of  Anesthesia  and  Intensive  Ce 

Milan,  Ospedale  Maggiore  IRCCS,  Mile 

Recent  mechanical  ventilators  allow  to  adjust  the 
pressurization  rate  (PR)  during  pressure  support 
ventilation  (PSV).  The  aim  of  this  study  was  to  eva- 
luate "in  vitro"  the  influence  of  PR  regulation  on 
the  inspiratory  effort  during  PSV. 

METHODS  We  studied  a  new  mechanical  ventilator  (Bear 
1000)  set  with  PEEP  10  cm  H,0  and  pressure  support  at 
10  cm  H20  at  three  different  PR  values  (arbitrary 
units):  low  (-5),  medium  (0)  and  high  (+5).  Tests 
were  performed  connetting  this  ventilator  to  an 
active  lung  simulator  (1)  set  to  mimic  low  (VT/Ti  = 
0.45  1  s"1)  and  high  (VT/Ti   0.9  1  s"1)  inspiratory 
drive.  We  measured  the  pressure  time  product  before 
(PTP1)  and  after  flow  delivery  (PTP2)(2). 
RESULTS  Results  are  presented  as  mean  ±  S.D. 
PR  LOW         MEDIUM  HIGH 

PTP1  (cm  H,0«s) 

Low  drive  0.04±0.004  0.04±0.002  0.04±0.004 
High  drive  0.02±0.005  0.04±0.007  0.03±0.003 
PTP2  (cm  H,0*s) 

Low  drive   1.39±0.08      0.39±0.05       0.21+0.04   * 
High  drive  3.2910.14  #    0.49±0.04  t  0.13+0.05  »* 

ANOVA:  *  p  <  0.01  between  different  PR;  #  p  <  0.05 
high  vs  low  inspiratory  drive. 

CONCLUSION  During  PSV,  PR  does  not  influence  inspi- 
ratory effort  to  trigger  the  ventilator.  After  inspi- 
ratory flow  delivery,  PR  regulation  may  actually 
reduce  inspiratory  effort,  particularly  when  inspira- 
tory drive  is  high.  We  may  conclude  that  PR  regula- 
tion is  an  important  tool  to  improve  patient- 
ventilator  synchrony. 

REFERENCE  1)  Intensive  Care  Med  1988,  14:60-3 
2)  Respir  Care  1992,  37:1056-69 

OF-95-083 


PREDICTIVE  EQUATIONS  FOR  DETERMINATION  PEAK  AIRWAY 
PRESSURE. 

Daniel  1_^   Reily  BS.  RRT.  William  Clark  AS.  RRT. 
University  of  Pennsylvania  Medical  Center,  3400 
Spruce  Street,  Philadelphia,  PA  19104-4283. 
Introduction:  When  patients  are  mechanically 
ventilated  many  variables  can  effect  peak  airway 
pressure(Paw)  such  as  lung  compliance,  flow  rate(FR), 
flow  pattern(FP)  and  endotracheal  tube(ETT)  size.  A 
clinician  would  find  it  helpful  to  be  able  to  predict 
PAW  before  a  change  in  FR,  FP,  EET  size  is  made.  This 
could  prevent  undesired  high  PAW  or  discern  what 
changes  are  necessary  to  reduce  PAW.  The  study  was 
undertaken  to  develop  equations  that  predict  Paw  with 
various  FP,  FR,  and  ETT  size.  Methods:  A  Purtian- 
Bennett  7200ae  ventilator  was  used  without 
humidifier.  A  silicone  ventilator  circuit  was 
attached  to  a  Marquest  swivel  adaptor(SA).  Each  ETT 
was  attached  to  the  SA.  The  volume  breaths  were 
discharged  through  the  ETT  to  the  atmosphere.  The 
resulting  Paws  for  each  ETT  and  selected  FP( square 
and  ramp)  were  recorded  at  FRs  from  20  L/m  to  120  L/m 
in  increments  of  5  L/m.  Five  Paw  measurements  were 
recorded  on  each  size  ETT  with  each  FP  and  FR,  then 
averaged.  To  insure  tidal  volume (VT)  was  taken  into 
account  the  same  procedure  was  used  for  VTs  of  0.6L, 
0.7L,  0.8L,  0.9L  and  1.0L.  In  all  25  data  points  were 
collected  and  averaged  for  each  ETT  at  each  FR  on 
each  FP.  Results/Equations:  Using  linear  regression 
six  equations  were  developed  to  predict  Paw  when  ETT 
size,  FR  and  FP  are  known. 


Size  6  EET  Square  FP 

Paw=45.14  +  1.002(FR-70) 

Size  7  EET  Square  FP 

Paw=24.82  +  0.582(FR-70) 

Size  8  EET  Square  FP 
Paw=14.71  +  0.346(FR-70) 
Conclusions:  The  equatio 
discriminate  between  increase 

induced  changes  verses  changes  in  selection  of  PF 
or  ETT  size.  A  pilot  study  is  underway  to  validate 
the  accuracy  and  clinical  benefit  of  the  equations 


Size  6  EET  Ramp  FP 

Paw=21.3  +  0.414(FR-70) 

Size  7  EET  Ramp  FP 

Paw=13.3  +  0.266(FR-70) 

Size  8  EET  Ramp  FP 
Paw=8.87  +  0.178(FR-70) 
enable  the  clinician  to 

to  patient 
FP 


INFANT  VENTILATOR  PERFORMANCE  VARIES  WITH  LUNG 
CONDITION  AND  CYCUNG  FREQUENCY.  Dennis    R     Bine.   Kendra   M 
Smith.    Stephen    J.    Boros,    Mark   C.    Mammel.    Infant    Pulmonary 
Research   Center.   Children's    Health   Care.    St.   Paul.    MN 
In    a    previous    study,    we    demonstrated    poor    performance    of 
conventional     infant     ventilators     at    rapid    cycling    frequencies 
(Pediatrics    1984;    74:487).    Does    the    new    generation   of   neonatal 
ventilators    exhibit    similar    limitations?       This    study    comp; 
(Vl)    and    minute    (Ve)    volume    delivery    of   8    current    neonatal 
ventilators    under    4    simulated    pulmonary    conditions    using    a 
Biotek    VT-2    test   lung.   We    monitored    pressures    at   the   proximal 
airway    (Paw)    and    within    the    "lung"    (PL),   and   Vl  delivery   to  th( 
lung  with   a  PeDS™  analyzer.  We  tested  the  Bear  Cub,  VIP  Bird. 
Drager    Babylog,    Infrasonics    500.    Newport    Breeze    and    Wave, 
Sechrist    100-V,    and    Siemens    300    ventilators    under    various 
conditions    of   compliance    (Crs,    ml/cmH20)    and    resistance    (Raw. 
cmH20/L/sec)  at  set  rates  of  25,  50,  75,   100,   125,  and   150  per 
minute.    We    also   studied    two    methods   of  management:    1)   constat 
peak       insptralory.pressure   with   25/5   PIP/  PEEP  and   I:E  ratio  of 
1:3,  2)   constant   Vt     delivery  of   10  ml,  PIP  variable,   rate  adjusted 
with   Te.    Mean   data    for   all    ventilators: 

Constant    PIP 


dal 


Rate 

Vt.   mis 

Ve.    mis 

mn    l>au 

Ve.    mis 

HMD 
Crs=l.  Raw=200 

25 

19 

486 

7 

277 

150 

7 

1028 

19 

1393 

HMD  <I000  gm 
Crs=l.  Raw=400 

25 

18 

477 

8 

260 

150 

5 

690 

26 

1180 

BPD 
Crs=3.  Raw=400 

25 

24 

591 

7 

269 

150 

4 

(,40 

30 

1269 

Normal 
Crs=3,  R»w»50 

2  5 

55 

1506 

6 

314 

150 

16 

2433 

7 

1368 

Ventilators    in    this    study    performed    similarly,    but    with    greater 
scatter   at   each   rate   than    those   tested   in    1984.    As   before,   high 
cycling    rates    caused    either    loss    in    delivered    Vt    or    increased    Taw 
to    maintain    Vt.    Inspired    Pl    fell    and   end-    expiratory   Pl     increased 
dramatically,    This    effect    was    less    pronounced    In    the    new 


tilair) 


clus 


ntila 


performance  still  decreases  at  high  cycling  frequency.  At 
rates,  tidal  volume  delivery  is  adversely  affected  and  expii 
gas  trapping  is  likely.  These  effects  are  most  pronounced  i 
conditions    with    long    respiratory    time    constants. 


rapid 
Blory 
I    lung 


VOLUME  ACCURACY  OF  THE  SIEMENS  SERVO  90OC  AND  NOVAMETRIX 
VENTRAK  WHEN  DELIVERING  HELIUM-OXYGEN  MIXTURES. 

Mark  Rogers  BS  RRT  RCP  Randy  Scott  BS  RRT  RCP  Tom  Malinowski  BS  RRT  RCP 

Leo  Langga  BS  RRT  RCP  Shamel  Abd-AJIah  MD 

Ronald  Perkin  MD  Daved  vanStralen  MD 

Loma  Linda  University  Children's  Hospital,  Loma  Linda,  California, 

BACKGROUND:  Mechanically  ventilated  patients  with  lower  airway  obstruction  (AO)  are 
prone  to  air-trapping,  increased  peak  inspiratory  pressures,  prolonged  expiratory  phase,  and 
auto-PEEP.  Low  density  helium -oxygen  (HO)  gas  mixtures  have  been  advocated  to  aid 
ventilation  in  patients  with  AO  We  sought  to  determine  the  accuracy  of  the  Novametrix 
VenTrak  and  Siemens  900C  pneumotachs  using  various  HO  mixtures. 
DESCRIPTION  OF  TECHNIQUE:  The  Servo  900C  is  set  up  using  a  helium  and  oxygen 
mixture  supplied  via  the  ventilator's  low  pressure  inlet  The  helium  and  the  oxygen  flows  are 
uuatcd  to  maintain  desired  R>  >;    Toi.il  HO  flow  is  maintained  greater  than  the  patients 
minute  ventilation  and  adjusted  to  assure  working  pressure  does  not  drop  dunng  a  breath 
cycle  The  Servo's  working  pressure  is  set  approximately  10  cmHjO  greater  than  the  patient's 
PIP  to  ensure  adequate  ventilaung  pressure 

EVALUATION  METHODS:  We  performed  a  bench  evaluation  using  a  Servo  900C  and 
VenTrak  monitor  at  five  concentrations  of  helium  (FIHe%)  0.  0  2,  0  5.  0  8,  and  1  0  The 
ventilator  circuit  wye  was  connected  to  a  VentAid  Training  Test  Lung  (TTL)  with  the 
compliance  set  to  0  45  I  -  cniH-.G  Expired  gases  from  the  ventilator  were  collected  in  a  tissot 
spirometer  A  VenTrak  flow  sensor  wbs  placed  between  the  pauent  wye  and  the  TTL  and  was 
calibrated  to  room  air  prior  to  testing,  The  ventilator  was  set  at  an  IMV  rate  of  10  and  a 
displayed  tidal  volume  of  500  cc  100  samples  were  taken  at  each  HO  mixture  tested  The 
minute  ventilation  control  of  the  900C  was  adjusted  to  maintain  a  "delivered  inspiratory"  tidal 
volume  of  500  ml  We  considered  the  tissot  spirometer  an  actual  representation  of  delivered 
volumes 
EVALUATION  RESULTS: 


Compansc 

n  of  mean 

idal 

olumes  a 

varvinR  RHe% 

KIHe% 

0 

0.2 

0.5 

0.8 

1.0 

Tissot 

500  ml 

50?  ml 

555  ml 

641  ml 

797  ml 

Servo 

500  ml 

500  ml 

♦  500  ml 

♦  500  ml 

♦  500  ml 

VenTrak 

t446ml 

♦40'  ml 

♦  156  ml 

♦  )0"  ml 

♦:39  ml 

♦  -  differs  significantly  from  tissot  volume  (p  >  0  05  t-test) 

CONCLUSIONS:  I)  The  Servo  WOC  ventilator  can  be  used  to  deliver  HO  mixtures 
2)  Volumes  displayed  by  the  Servo  and  VenTrak  will  read  significantly  less  than  actual 
delivered  volumes  3)  The  error  introduced  by  HO  increases  with  increasing  helium 


1206 


rkspiratorv  Care  •  November  '95  vol  40  no  n 


Tuesday,  December  5,  1:00-2:55  pm  (Rooms  230C-D) 


RESISTANCE  INCREASE  IN  A  BREATHING  CIRCUIT  FILTER  WHEN  USED  IN 
CONJUNCTION  WITH  CONTINUOUS  NEBULIZED  BRONCHODILATION 

Leo  Lanaaa  BS  RCP  RRT.  Skip  Garton  RCP  CRTT,  Randy  Scott  BS  RCP  RRT,  Ron 
Perkin  MD.  Douglas  Deming  MD.  Tom  Malinowski  BS  RCP  RRT,  Mark  Rogers  BS 
RCP  RRT.  Loma  Linda  University  Children's  Hospital.  Loma  Linda,  California 

INTRODUCTION:  Breathing  circuit  filters  (BCF)  are  commonly  used  in  protecting  the 
integral  components  of  a  ventilator's  electronic  spirometer.  Current  literature  shows 
little  clinical  research  on  the  Increased  resistance  and  potential  increase  in  work  of 
breathing  that  a  BCF  may  Impose  when  used  In  conjunction  with  continuous 
nebulized  bronchodilation.  We  hypothesized  that  the  resistance  (R)  created  by  a  BCF 
may  significantly  Increase  overtime  METHODS:  To  simulate  In-line  continuous 
nebulized  bronchodilation  delivery  in  conjunction  with  BCF  usage,  full  strength  (0.5%) 
albuterol  was  nebulized  with  a  Heart™  large  volume  nebulizer  at  a  flowrate  of  12 
LPM.  Standard  large  bore  tubing.  1 .5  meters  in  length,  was  attached  proximally  to  the 
aerosol  outlet  port  and  distally  to  a  Pall  BB-50T  BCF  The  BCF  was  oriented  vertically 
to  facilitate  drainage.  At  timed  Intervals  (0,  10,  20,  25,  30,  35,  and  40  minutes)  the 
BCFs  were  removed  from  the  circuit,  and  various  flows  (0  06,  0  13,  0.19.  0.26.  and 
0.32  L/s)  were  delivered  through  a  Cole-Parmer  calibrated  rotometer.  Pressure 
gradients  were  then  measured  using  a  Gould-Statham  TC  131  differential  pressure 
transducer  connected  to  a  Grass  Model  7  chart  recorder  Pressure  measurement 
points  were  equidistant  at  6  5  cm  pre  and  post  BCF  center  Resistance  was 
calculated  from  pressure  gradients  measured  across  each  Individual  filter  divided  by 
standard  flows  delivered  through  a  calibrated  rotometer.  The  filter  resistances 
obtained  at  the  different  timed  intervals  were  then  compared  to  those  obtained  before 
initiation  of  nebulization  at  equivalent  standard  flows  RESULTS:  A  total  of  16 
individual  BCF's  were  tested,  and  a  comparison  performed  between  the  resistances; 
pre-nebulization  (control),  and  post-nebulization.  A  Two-way  ANOVA  analysis  was 
then  used  between  groups  The  results  were  as  follows: 


T(min) 

0 

10 

20 

25 

30 

35 

40 

R  mean 

(cmH?0/Us) 

1.33 

2.07 

11.68 

1652 

31  06 

40.5 

27.61 

4  R  (%) 

na 

56% 

778% 

1122% 

2235% 

2945% 

1975% 

T=  time,  R=resistance,  Jft=%  increase  when  compared  to  pre-nebulization  R. 
The  BCF's  at  10  minutes  had  a  statistically  significant  Increase  in  R  (p  <  0.05).  The 
consecutive  resistances  measured  at  20,  25.  30.  35,  and  40  minutes  were  also 
statistically  significant  (p  <  0.05)  for  an  increase  in  resistance. 
CONCLUSIONS:  The  resistance  Imposed  by  BCF's  is  significantly  increased  over 
time  and  should  be  used  with  caution  when  applied  with  In-line  continuous  nebulized 
bronchodilation.  Further  studies  need  to  be  done  to  look  at  the  effect  of  other  types  of 
medications  on  BCF  resistance  and  the  increase  in  work  of  breathing  that  may  result. 


DYNAMIC  MEASUREMENTS  OF  INTRINSIC  PEEP  DO  NOT  REPRESENT 
THE  LOWEST  INTRINSIC  PEEP. 

Yuhii  Fuiino.MD.  Masaji  Nishimuri,  MD,  Dean  Hess,  PhD.  RRT.  Robert  M. 
Kacmarek,  PhD.  RRT    Osaka  University  Hospital,  Hyogo  College  of  Medicine,  Japan 
and  Massachusetts  General  Hospital,  Boston,  MA. 

Although  intrinsic  positive  end -expiratory  pressure  (PEEPi)  has  been  described 
primarily  in  patients  with  COPD.  it  is  also  common  during  mechanical  ventilation  of 
patients  with  acute  respiratory  failure.  PEEPi  is  usually  measured  using  static 
conditions  by  occluding  the  airway  opening  at  end-exhalation  (PEEPi-stat).  Dynamic 
PEEPi  (PEEPi-dyn)  is  the  airway  pressure  required  to  overcome  expiratory  flow  and 
has  been  considered  to  represent  the  lowest  regional  PEEPi.  There  has  been  little  data 
to  validate  this  assumption    The  purpose  of  this  study  was  to  compare  PEEPi-dyn  with 
PEEPi-stat.  Metbods:   Measurements  were  performed  in  5  adult  white  rabbits  who 
were  anesthetized,  tracheotomized,  and  intubated  with  uncuffed  endotracheal  tubes 
(2.0,  2.5,  3.0,  or  3.5  mm  ID).  The  trachea  was  tied  to  prevent  air  leak.  The  animals 
were  ventilated  (Servo  900C)  using  a  low  compliance  circuit    Airway  pressure  was 
measured  at  the  proximal  endotracheal  tube  with  a  pressure  transducer  and  flow  was 
measured  simultaneously  at  the  proximal  endotracheal  tube  with  a  hot  wire 
anemometer.  Pressure  and  flow  signals  were  amplified,  digitized,  and  recorded 
(CODAS,  Dataq)    The  animals  were  paralyzed  and  ventilated  in  the  supine  position. 
Baseline  ventilator  settings  were  a  rate  of  50/min,  I:E  ratio  of  2:1,  and  minute 
ventilation  manipulated  to  create  3  or  5  cm  H:0  PEEPi-stat.  PEEPi-stat  was  measured 
using  the  expiratory  hold  button  of  the  ventilator    PEEPi-dyn  was  measured  from  5 
respiratory  cycles  immediately  prior  to  measurement  of  PEEPi-stat.  The 
measurements  were  repeated  3  times  for  each  ventilator  setting  and  each  endotracheal 
tube  size.  Results:   PEEPi-dyn  showed  large  variations  with  ventilator  settings  at  the 
same  PEEPi-stat  level  <P  <  0.05).  Differences  between  PEEPi-dyn  and  PEEPi-stat 
increased  with  increased  minute  ventilation  (P  <  0  05). 


endotracheal 
tube  size 

target  PEEPi-s 

at  of  3  cm  H,0 

target  PEEPi-stat  of  5  cm  HjO 

PEEPi-stat 

PEEPi-dyn 

PEEPi-stat 

PEEPi-dyn 

2.0 

2.64  ±0.58 

4.06  ±0.89 

5.30  ±0.18 

7.70  ±0.67 

2.5 

3.05  ±0.16 

4.45  ±0.37 

J  86  t  0  08 

7  49  ±0  70 

3.0 

3.19±023 

5.08  ±0.53 

4.96  ±0.70 

8  54  ±0.91 

3.5 

3.00  ±0.33 

5  07  ±0.51 

S  12  ±  0.37 

9.71  ±0.94 

Conclusions:  In  this  animal  model  with  normal  lung  function,  PEEPi-dyn  exhibited 
large  variation  with  ventilator  settings  and  minute  ventilation.  The  fact  that  PEEPi-dyn 
was  greater  than  PEEPi-stat  strongly  suggests  that  PEEPi-dyn  does  not  reflect  the 
lowest  regional  PEEPi. 

OF-95-126 


ABILITY  OF  BILEVEL  CPAP  VENTILATORS  TO  MEET  INSPIRATORY  DEMAND: 
A  LUNG  MODEL  STUDY 

Thananchai  Bunburaphone.  MD,  Hideaki  Imanaka,  MD,  Masaji  Nishimura,  MD, 
Dean  Hess,  PhD,  RRT,  Robert  M.  Kacmarek,  PhD,  RRT 

Department  of  Anesthesia  and  Respiratory  Care,  Massachusetts  General  Hospital  and 
Harvard  Medical  School,  Boston  MA. 


Bilevel  CPAP  ventilators  are  being  increasingly  used  to  provide  noninvasive  ventilatory 
support  during  acute  ventilatory  failure    We  evaluated  the  ability  of  six  bilevel  CPAP 
ventilators  to  meet  varying  levels  of  inspiratory  demands  in  a  single  compartment  lung  model 
Methods:  The  lung  model  was  set  at  a  compliance  of  50  or  80  mL/cmHjO  and  a  resistance  of 
8  cmHjO/L/s  with  a  rate  of  10  /min  and  an  inspiratory  time  of  1 .0  sec.  The  Respironics  BiPAP 
S^T-D.  the  Puritan  Bennett  320I/E  and  335,  Sullivan  VPAP,  Pierre  Medical  O'NYX,  and 
SEFAM  Ventil+  ventilators  were  compared  to  the  Puritan  Bennett  7200ae  (Flow-by,  base  flow 
of  10  L/min  and  flow  sensitivity  of  3  L/min)  at  lung  model  peak  inspiratory  flow  of  20,40,  60, 
and  80  L/min.  Initiation  of  inspiration  and  expiration  were  determined  by  measurement  of 
pressure  in  the  lung  model  pleural  space.  Pressure  and  flow  at  airway  opening  were  also 
measured.  All  ventilators  were  set  at  an  IPAP  of  1 5  cmH20  and  EPAP  of  5  cmH30.  The 
subbaseline  inspiratory  pressure  change  (P-I),  inspiratory  delay  time  (D-I),  suprabaseline 
expiratory  pressure  change  (P-E),  expiratory  delay  time  (D-EJ,  and  the  area  %  inspiration 
(Area%)  were  determined.  The  Area%  was  defined  as  the  percentage  of  pressure  time  product 
of  airway  opening  pressure  above  EPAP  during  inspiration  to  the  area  of  the  rectangle  created 
by  (IPAP  -  EPAP)  and  inspiratory  time.  Statistical  analysis  was  done  by  ANOVA  with 
Scheffe  test  (P  <  0.05).     Results:  Differences  among  ventilators  (P  <  0.05)  were  noted  for  all 
variables  evaluated.  P-I,  D-I,  and  P-E  were  significantly  different  among  peak  flows  (P  < 
0.05).  Compliance  settings  did  not  significantly  effect  any  variable.  Mean  values  for  3 
breaths  at  50  mL/cmH,0  compliance  and  40  L/min  peak  flow  are  listed  below.  Negative  D-E 
indicates  premature  expiratory  cycling. 


7200ie 

S/T-D 

VPAP 

32(11  t 

O'NYX 

Ven(ll+ 

PB335 

P-I  (cmH20) 

2.97 

rig 

108 

0.92 

1  33 

1.69 

1.38 

D-l  (s«) 

0  19 

0.09 

029 

0.09 

0  06 

0.18 

Oil 

P  FlcmlUOl 

4  15 

2.51 

3  18 

2 

0 

1  08 

0 

D-E(i«) 

Oil 

0  08 

039 

006 

-0  18 

0.06 

-0.1 

Art.V.  (%) 

61  79 

83.52 

43.97 

8348 

75.82 

66.08 

75.81 

Conclusions:  The  ability  of  bilevel  CPAP  ventilators  to  meet  inspiratory  demands  equaled  or 
exceeded  that  of  the  PB7200ae  However,  large  differences  did  exist  among  the  functions  of 
the  bilevel  CPAP  ventilators. 


Call  for  Abstracts 

1996  Respiratory  Care  Open  Forum 


Early  Deadline:  February  11,  1996 

Accepted  abstracts  will  be  printed  in  the 
October  1996  issue  of  Respiratory  Care 

Selected  authors  will  present 

their  research  at  the  Open  Forum  during  the 

1 996  AARC  Annual  Meeting  in 

San  Diego,  California 

See  pages  1223-1224  for  more  information 


Respiratory  Care  •  November  '95  Vol  40  No  11 


1207 


On 


mly  PulseDose 

delivers  a  consistent 

dose  of  oxygen  at  the 

very  moment  it's 

needed-on  the  leading 

edge  of  inspiration- 

with  every  breath. 

That  means  your 

patients  always  get 

the  right  amount  of 

oxygen,  even  during 

exercise  and  breathing 

pattern  changes. 

And  because  many 

patients  find  PulseDose 

more  comfortable, 

they're  likely  to  wear 

their  oxygen  constantly, 

resulting  in  better 

compliance. 


FUlseJDose 


The  Right  Dose. 


On  Demand. 


With  Every  Breath. 


XulseDose  is  good 
for  your  business  too. 
Significantly  reduced 
oxygen  consumption 
means  greater  oxygen 
efficiency  for  hospital 
use,  emergency  transport 
and  ambulatory  oxygen 
patients.  Because 
PulseDose  is  available 
in  several  configurations 
for  use  with  the  hospital 
headwall,  compressed 
gas  cylinders  or  portable 
liquid  oxygen  sources, 
we  have  just  the  right 
product  to  meet  the 
demands  of  your  business 
and  your  patients. 

J— /eVilbiss-We're  on  the 
leading  edge  of  home 
oxygen  systems. 

lo  demand  the  best,  call 
USA  814-443-4881  or  fax 
814-443-7572.  attention 
DeVilbiss  International. 


©1095  DHC,  INC. 


m 


Circle  162  on  reader  service  card 
Visit  AARC  Booths  1010, 1012,  and  1014  in  Orlando 


DEVILBISS 

SUNRISE  MEDICAL 


OPEN  FORUM  ABSTRACTS  Circle  1 10  on  reader  service  card 


With  The 

Information 

Service  Card,  You 

Can  Stop 

Searching  And 

Start  Buying. 

Get  the  facts  on  all  the  products 
and  services  advertised  in  this 

issue  easily  and  quickly. 

The  computerized  Information 

ServiceCard  does  it  all.  Simply 

fill  in  your  name  and  address, 

check  the 

appropriate  boxes, 

and  mail  or  fax  it. 


These  abstracts  were  accepted  for  the  Open  Forum  ;  however,  the  presenters  are  unable  to  attend. 


seam  •  less  (senilis)  adj. 


No  seams; 

no  interruptions. 


TBircT  Ventilator 
Systems. 


EVOLUTION  OF  A  BREATH  BY  BREATH  METABOLIC  SYSTEM:  A 
RETROSPECTIVE  STUDY  IN  THE  ACCURACY  OF  RESTING  METABOLIC 
MEASUREMENTS  USING  PHYSIOLOGICAL  CONTROLS 

by  H .  Kist  MS  RRT  RPFT,  D.  Johnson  BS  RRT  RPFT,  K.  Arnold 
CRTT  CPFT,  and  W.  McKenzie  Jr.  PhD 

Mr.  Kist  is  affiliated  with  Truman  Medical  Center  -East, 
Kansas  City,  MO 

Medical  Graphics  Corporation  (MGC)  proposes  that 
their  newer  "CCM"  system's  metabolic  measurements  are 
more  accurate  than  their  "2001"  system  due  to  improved 
breath  by  breath  (bxb)  algorithms. 

To  investigate,  52  quality  control  (QC)  studies  were 
reviewed  from  both  the  CCM  (n=26)  and  2001  (n=26).  These 
QC  studies  had  been  used  to  verify  MGC  system's 
performance  by  comparing  MGC's  bxb  carbon  dioxide 
production  (VCO,)  and  oxygen  consumption  (VO.)  values  to 
those  simultaneously  obtained  using  a  manual  method  (MM) 
using  traditional  (non  bxb)  equations.  MGC  systems  were 
prospectively  considered  to  be  operating  within 
specifications  if  MGC  VCO.  and  VO,  values  agreed  within 
ten  percent  (10%  maximum  error  =  5%  MGC  +  5%  MM)  of  the 
MM  values.  Respiratory  quotients  (RQ  =  VCO,/VOj)  were 
not  utilized  in  acceptance  of  QC  studies.  The  QC  studies 
were  done  five  years  apart  using  different  volunteers. 


The 


ed  data 


ited: 


2001  STUDIES 

CCM  STUDIES 

MGC   MM   ERR 

R 

MGC   MM   ERR   R 

331   326  <2% 

0.991 

237   245  <3%   0.963 

347   343  <2% 

0.981 

280   289  <3%   0.951 

.945  .944  <1% 

0.946 

.850  .850  =0%   0.944 

LEGEND:   ERR  = 

error, 

R 

=  correlation  coefficient. 

Mean  VCO,  and  VC 

,  values 

ar 

e  milliliters/minute  STPD. 

The  statistical 

analys 

is 

for  correlation,  mean,  and 

nee  did  not  show  a  sig 

ni 

Eicant  difference  (p=0.01) 

between  both  MGC  systems  and  the  MM. 

Although   the   new   algorithms   contributed   to 
slightly  better  mean  RQ  but  worse  VCO,  and  VO,  agreemen 
between  the  CCM  and  the  MM,   these  findings  were  no 
significant.    Thus,   it  was  concluded  that  the  CCM* 
measurements  were  no  more  accurate  than  the  2001's. 


AEROSOLIZED  MEDICATION  RAINOUT  MAY  INFLUENCE  THE 
TIME  INTERVAL  BETWEEN  VENTILATOR  CIRCUIT  CHANGES. 
P.  Mc Fa llis.  BS.  RRT.  Rockcastle  Hospital  and  Respiratory  Care 
center,  Mt.  Vernon,  Ky. 

Some  disagreement  exists  as  to  the  frequency  at  which  ventilator 
circuits  should  be  changed.  Current  literature  suggests  that  factors 
influencing  the  time  interval  between  circuit  changes  include  infection 
control  issues,  the  type  of  equipment  used,  the  circuit  appearance,  and 
proper  function. 

By  monitoring  circuit  cultures  of  nonheated  ventilator  circuits  at 
the  wye  on  6  stable  long-term  ventilator  dependent  patients  for  one 
month,  we  investigated  the  possibility  of  decreasing  the  frequency  of 
our  circuit  changes  from  3  days  to  7  days.  However,  during  the  41"  to 
the  5"*  day  of  the  study,  a  semiviscous  yellow  residue  with  a  sulfurous 
odor  was  noted  at  the  exhalation  side  of  the  patient  wye  in  the  circuit, 
which  residue  continued  to  appear  at  about  the  same  time  interval  even 
after  the  circuit  was  changed.  A  sample  by  culturette  sent  to  the  lab  for 
analysis  revealed  an  unknown  inorganic  substance  that  does  not 
contain,  support,  or  promote  microbial  growth.  Patient  sputum  cultures 
were  negative  for  the  unknown  substance.  Independent  lab  analysis  of 
the  residue  by  FT  infra-red  spectra  and  pyrolysis-gas  chromatograpby- 
mass  spectrometry  revealed  aerosolized  metabolites  (acetamide) 
consistent  with  the  mucolytics  used  with  in-line  bronchodilator 
treatments. 

Infection  control  reports  during  the  month  of  the  study,  and 
follow-up  reports  after  the  study,  indicated  that  based  on  our 
nosocomial  pneumonia  criteria,  no  outbreaks  of  pneumonia  were 
reported  with  the  increased  time  interval  between  circuit  changes. 
We  concluded  that  even  though  the  circuit  cultures  were  negative  for 
microbial  growth,  over  the  7  day  interval,  aerosolized  medications  and 
the  frequency  at  which  they  are  administered  in-line  may  indirectly 
affect  the  factors  that  influence  the  time  interval  between  circuit 
changes. 


Respiratory  Care  •  November  '95  Vol  40  No  1 : 


1209 


OPEN  FORUM  Author  Index 


Boldface  type  indicates  presenters. 


A 

Abhasi.  Soraya    1 1 79 

Abd-Allah.  Shame] 1206 

Adams.  Alex 1 177 

Allaway,  Linda  1152 

Anders,  Michael  1162 

Anderson,  B 1 1 79 

Anderson,  Jeff 1 194  (3) 

Anderson.  Jennifer  E 1 172 

Andreoni.  Patrizia 1 206 

Arnold.  John  H    1 157 

Arnold.  K 1209 

Arrington,  Ponce 1 160 

Arroliga,  A    1176 

Atkins,  Harold  L 1182 

August.  Anna 1 164 

B 

Backes,  WJ   1176 

Ballard.  Julie 1192.  1 193,  1202 

Bandy,  Kenneth  B 1 198 

Bankson.  Daniel  D   1 176 

Barnes,  Thomas  A 1192 

Barrett.  L 1200 

Bartlett.  Robert  H   1 198  (2) 

Barton.  JA 1 169 

Batchelor.  Melissa 1172 

Battisti.O    1157 

Beggs,  Virginia 1173 

Belingon,  Ed 1 161,  1 195 

Bennett,  N  Tate 1157 

Bertrand,  Jean  Marie 1 157 

Betit,  Peter    1 157.  1186, 1187 

Bhutani.  Vinod  K    1 179 

Bien,  Mauo-Ying    1181 

Bing.  Dennis  R 1 178. 1193, 1198  (2).  1206 

Black,  Zenobia   1 195 

Blanchette.  Tim 1152 

Bliss,  Peter 1 177 

Blondin,  Joan 1 156 

Boros,  Stephen  J  1 198  (2),  1206 

Branson,  Richard  D    1174,  1204 

Brown,  RA    1 176 

Brudno.  D  Spencer 1 178 

Buck,  Curtis 1201 

Bunburaphong.  Thananchai   1207 

Burke,  P 1174 

Burke,  William  1 172 

Burns,  David 1173(2),  1185 

Burton,  Karen  Kay    1  160 

C 

Cabahug.  Corazon  J   1 182 

Caouctte,  Yvonne  1184 

Capots,  MD 1152 

Carlson,  Jeff  1192 

Cefaratt,  John   1184 

Chang.  David  W 1154,  1155 


Channick,  Richard  N 1 184 

Chatburn,  Robert  L 1 165,  1 177.  1205 

Cheifetz,  Ira  M    1 172  (2) 

Chen,  Wun-Hsiu 1181 

Chikhmirzaeva.  Elmira  K 1 179 

Child,  Jeff  1204 

Chiumello,  Davide    1205 

Christopher,  K 1 156 

Clanton,  Thomas  L 1 156,  1 158 

Clark,  William 1206 

Colombo,  J    1 165 

Cooper,  Larry   1201  (2) 

Cornere.  B 1201 

Costarino,  Andrew    1 158  (2) 

Cowan,  Wes   1205 

Cox,  Timothy  J   1175 

Craemer.  Susan 1 153 

Croci,  Massimo 1205, 1206 

Cuadrado,  Angel  R 1 158 

Cuccia,  Ann 1 1 82 

Cunningham,  James  C    1 197 

D 

Daugherty.  Gena 1 164 

Davis,  Kenneth  Jr 1 174,  1204 

Delgado.  Edgar 1196 

Deming,  Douglas    1207 

Dennison,  Frank  1178 

deRegnier,  Raye  Ann   1 198  (2) 

Derosa,  A 1 197 

Deshpande,  Vijay   1181 

Dhand,  R 1182 

Douglas,  Clifford    1 197 

Dove,  B  1201 

Dunlevy,  CL  1152, 1153  (2) 

Dushay,  KM    1 174 

Dyer,  David 1 184 

E 

East,  Thomas  D 1194  (3) 

El-Khatib,  Mohamad  F 1 174 

El-Lessy,  Hussein  N 1 197 

Elbarbary,  Mahmoud    1 184 

Emad,  Ali 1163  (2) 

Emberger.  John 1 194 

Eng,  William  E  1 176 

Epley,  Deborah  1 195 

Eyler,  Roxanne   1 195 

F 

Fahey.PJ 1161 

Fallat,R 1 178.  1179 

Fawcett,  Deborah   1 1  (">2 

Feldman.  M 1 1 74 

Fielden.  Nina  M    1 1 54 

Fink.  James  B 1154.  1161,1182,1195.  1200 

Fisher,  Daniel   1185 

Fisher,  Jean  1 1 65 

Foster,  Charles   1  INI.  1200 


1210 


Respiratory  carl  •  novhmbkr  '95  vol  40  No  i 


With  The 

Information 

Service  Card,  You 

Can  Stop 
Searching  And 
Start  Buying. 

Get  the  facts  on  all  the  products 
and  services  advertised  in  this 

issue  easily  and  quickly. 

The  computerized  Information 

ServiceCard  does  it  all.  Simply 

fill  in  your  name  and  address, 

check  the 

appropriate  boxes, 

and  mail  or  fax  it. 


seam  •  less  (sem  lis)  adj. 


efinition:     No  seams; 


V 


no  interruptions. 


Synonym :     TBird™  Ventilator 
Systems. 


SWP  PFtOOUCTB  C 

TbiBjerrtw  electron  Company 


Circle  110  on  reader  service  card 
Visit  AARC  Booth  724  in  Orlando 


Here's  one  you've 
really  got  to  see! 

The  New  JCAHO  Hospital  Standards: 
Their  Effect  on  Respiratory  Care 

A  Videotape  from  the  Professor's  Rounds 
in  Respiratory  Care  Videoconference  Series 

Featuring  Nancy  Telford,  BS,  RRT,  Program  Manager,  Joint 
Commission  on  Accreditation  of  Healthcare  Organizations,  with 
Moderator  Sam  P.  Giordano,  MBA,  RRT,  AARC  Executive  Director 

The  new  /  995  Accreditation  Manual  lor  Hospitals  is  now  organized  around  functions  that 

impact  patient  outcomes,  and  the  standards  are  now  integrated  into  functional  chapters  rather 

than  a  single  chapter.  Through  this  overview,  you  will  learn  about  standards  related  to 

competence  programs,  responsibilities  of  deportment  leaders  and  medical  directors,  and  expectations  on  performance  improvement. 

This  video  also  reviews  the  interactive  survey  process  and  the  role  of  department  staff.  90  minutes.  Item  VC51  —  $275  {S305  nonmembers 

Please  send  me  "The  New  JCAHO  Hospital  Standards:  Their  Effect  on  Respiratory  Care."  Item  VC51  —  $275  ($305  nonmembers) 


Payment  enclosed  $_ 


Charge  to  Purchase  Order  #_ 


Charge  to  my  IHVisa  □  MasterCard.  Card  expires 

AARC  Member  Number 

Address 


Card* 


ffease  Note:  Videotapes  do  not  qualify  viewer  lor  CRCE  credit. 
Signature 


Name/lnstitution_ 


City/State/Zip_ 


Mail  to:  AARC,  1 1030  Abies  Ln.,  Dallas,  TX  75229-4593  •  (214)  243-2272  •  FAX  (214)  484-2720 


Patient  to  ICU         Change  Ventilator 


Patient  to  X-Ray         Change  Ventilator 


Patient  to  Operating  Room         Change  Ventilator 


nft 


Patient  back  to  ICU         Change  Ventilator 


How  many  ventilators 
do  you  need  to  take 
care  of  your  patient? 

Just  one.  TBird. 

The  Seamless  Solution. 

Each  time  you  change  ventilators,  it  can  put  your 
patient  at  risk.  But  TBird,"  a  revolutionary  new 
turbine-powered  ICU  ventilator  system,  is 
designed  to  stay  with  your  patient.  There  are  no 
seams,  no  interruptions,  so  fewer  complications 
occur.  And  since  one  piece  of  equipment 
performs  so  many  jobs,  costs  are  lower  too. 
To  take  your  patient  seamlessly  through  the 
continuum  of  care,  nothing  performs  like  TBird." 

Call  your  local  Bird  representative  or 

1-800-328-4139 


for  more  information 


See  the  TBird"  family  of  ventilators 
at  AARC  Booth  #724 


S!SU 

BIRD  PRODUCTS  CORPORA  TION 
A  Thermo  Electron  Company 

The  Breath  of  Technology 

Palm  Springs,  California  •  619. 778. 7200 
Fax  '  619. 778. 7274 
Circle  110  on  reader  service  card 


».i 


Open  Forum  Author  Index 


Francis.  Richard    1 165 

Francois,  A   1157 

Fraser.  Victoria 1 200 

Frentzel.  Micheal    1 186 

Fujino,  Yuji 1 186,  1207 

G 

Gadek.  James  E 1 158 

Gagliardi.  J   1 197 

Galler,  D   1164 

Garton.  David  1185 

Garton,  Skip   1207 

Gattinoni,  Luciano   1205,  1206 

Gauger,  P 1198 

Gaviola.  Sandra 1 155 

Gay,  Peter  C   1 168 

Geller,  David 1 165 

Gerstmann.  Dale 1 157,  1201  (2) 

Godinez,  Rodolfo  I 1 158,  1 1 73 

Goldstein,  Mark 1193  (2) 

Goulet,  Robert  L 1205 

Gowski,  Diane 1 196 

Gradwell,  Gary  1195 

Gradwell,  Lynda 1 153,  1 160 

Granzo,  Jim 1 192 

Graves,  Marcia  Roberts    1161 

Graybeal,  JM 1177 

Green  way.  Loren    1 160,  1 161 

Grenier,  Barry 1 1 86,  1 1 87 

Grychowski,  J 1182 

Guiles,  Stan 1204 

H 

Haas,  Carl  F 1 198  (2) 

Habib,  D   1161,  1170 

Haggerty,  E 1161 

Halees,  Zohair 1 1 84 

Hallberg,  T   1 165 

Hansen-Flaschen.  John 1 153,  1 160 

Hargett,  Ken   1 153 

Harrison,  P   1156,1164,  1197 

Haskill,  Ron 1201  (2) 

Haver,  Virginia  M 1176 

Hayes,  Joyce  1 200 

Head,  C  Alvin 1 184,  1 185 

Hearns,  Mona  1 200 

Hensley,  KA  i  152 

Hess,  Dean 1184,1185,  1186(2),  1192,  1196(3), 

1197,  1205.  1207(2) 

Heulitt.  Mark  J    1 204 

Higgins.  Barbara 1 169 

Hill.Wrae   1184 

Hirschl,  Ronald  B    1 198  (2) 

Hirschtick.  Robert 1202 

Hoffman,  Leslie    1  196 

Holhrook.  Paul    1204  (2) 

Holt.  Shirley   1204 

Hopper.  Andrew  1 185 

Hordvik.  N 1165 

Horiuchi,  K   1174 


Hossin,  Linda    1200 

Hough,  Lorraine  F 1158(2),  1159,  1173 

Howenstine.  Michelle 1 165 

Hoyt,  Mark   1 194 

Hsu,  Wun-Jie 1181 

Hughes,  Kenneth 1 182 

Hurford.  William  E 1 185 

Hussey,  John  D 1 176 

1 

Imanaka.  Hideaki  1 186,  1 192,  1196  (3),  1 197,  1207 

Itable,  C 1174 

J 

Jacobson,  Kathy    1 173  (2),  1 185 

Johannigman,  Jay  A   1 1 74,  1 204 

Johnson,  D 1209 

Johnson,  F  Wayne 1173  (2),  1 184,  1185 

Juhl,  Bent 1157 

Jurgeson,  S    1 156 

K 

Kachel,  Diane   1 182 

Kacmarek,  Robert  M 1184,  1185(2),  1186(2).  1192, 

1196(3).  1197,  1205.  1207(2) 

Kallstrom,  Thomas  J 1165,  1 177 

Kandal,  K   1 178,  1 179 

Kanov,  Laura  N 1162 

Kasel,  Debra  K  1152 

Kasper,  CL    1169 

Kavuru,  MK    1 176 

Kean,  Charles   1 197 

Keenan,  Jim 1193, 1202 

Keller.  Robert  M 1154 

Kellogg,  Kim 1 162 

Kemp,  James  S   1 164 

Kemper.  M    1174 

Kendall.  Allen  G 1168 

Kendrick,  KG   1 174 

Kennedy,  Sharlene   1 195 

Kern,  Frank  H   1 172  (2) 

Kester,  Lucy   1169 

Kinder,  A  Tupper   1161 

Kinninger,  K  Knaus   1173  (2).  1 185 

Kirmse.  Max  1196 

Kist,  W 1209 

Kollef,  Marin 1200 

Kramer.  Christopher 1201 

Krause,  S 1200 

Kremenchugsky,  Vladimir 1 1 78 

Kriner,  Steven  J 1 169 

Kuyper.  Cecelia 1 1 72 

L 

LaChaunce,  Wendy  L 1156 

Lain.  David   1178 

Lakshminarayan.  Sambasiva    1 176 

Lamb,  Billy  M 1181  (2).  1200 

Langga,  Leo  1 168,  1 185,  1206,  1207 

Langhendries,  JP 1157 

Laskowski,  DM 1176 

Lassen.  Gordon 1157.  1201  (2) 


1214 


Respiratory  CARE  •  November  '95  Vol  40  No  1 1 


Open  Forum  Author  Index 


Lough,  Mary  E    1168 

Lovelady,  Timothy  C   1177 

Lu,  Chong-Chen  1181 

Lund,  Mark 1 156 

Lybarger,  Edwin  M 1180  (2) 

Lyles,  Ruth   1161 

M 

MacDonald,  GF 1 174 

MacDonald,  Kelvin 1184,  1205 

Male.N  1153 

Malinowski.  Tom 1154.  1 168, 1197,  1206,  1207 

Mallory,  George  B  Jr   1 164 

Mammel.  Mark  C 1 178,  1 193,  1 198  (2),  1206 

Mang,  Harald 1 196 

Martin,  Jim    1 169 

McCarthy,  K  1 176  (2) 

McCloskey,  John  J   1 175 

McCoy,  Bob   1 177 

McEwen,  Pat 1 194 

McFalls,  D 1209 

McGowan,  Mary 1179 

McKenzie,  W  Jr   1209 

McPeck,  Michael 1182  (2) 

Meliones,  Jon  N 1 172  (2) 

Menegaz.  Lisa 1 195 

Meredith,  Keith 1 157 

Meredith.  Rebecca  L 1154 

Metcalf,  Sandy  M 1160,  1161,  1 194 

Meyers,  Patricia  A 1178,  1 198  (2) 

Miller,  Chris   1184 

Miller,  Dori 1 156 

Miller,  M 1 161,  1 170 

Minton,  Stephen   1 157 

Miro,  Adelaida    1 196 

Mitchell,  T 1161,  1170 

Moen,  Suellen  G 1202 

Monaco,  Frank   1 157 

Morris,  A 1201 

Morris,  Alan  H  1 160,  1161 

Mullins,  Durinda 1164 

Munroe,  SW    1174 

Murphy,  Edrie 1 178 

N 

Nakanishi,  Albert  K    1181  (2) 

Napoli,  Linda  Allen    1 158  (2),  1 159,  1 173 

Nash,  Lila   1 195 

Negroni,  Lucia    1206 

Newhart,  John 1184,  1 185 

Nichols,  Greg   1 169.  1 170 

Nilsestuen,  Jon   1 153 

Nishimura,  Masaji 1186,  1207  (2) 

Norregaard,  Ole 1157 

Norsa,  Alba 1206 

Nugent,  William  1 173 

Nygard,  Karen  S  1 169 

O 

O'Callahan,  Thomas 1 197 

O'Donnell,  C 1 174 


Oleksiuk,  M 1 176 

Olfert,  Mark 1 197 

Oliver,  Sharon 1 195 

Onorato,  D    1156.  1164,1197 

Op't  Holt,  Timothy  B 1156,  1 158 

Orec,  R 1201 

Orons.  Amy 1156.  1178 

O'Rourke,  Maureen   1 158,  1 159 

P 

Palevsky,  Harold 1 153,  1 160 

Palmer,  Lucy  B  1 182 

Parkman,  Anna  W 1165 

Patrick,  Herbert   1156.  1160,  1178.  1194,  1195 

Pavlik,  Daniel 1169, 1170 

Pearson-Shaver,  T 1 186 

Pelosi,  Paulo 1205,  1206 

Perez-Trepichio,  P 1162 

Perkin,  Ronald    1 168,  1206,  1207 

Perlman,  Lauren   1157 

Perry,  Douglas  G 1164,  1 182 

Peruzzi,  William  T  1202 

Peterson,  B    1 164 

Peterson.  Lance 1202 

Petsinger.  Douglas  E 1 158 

Peverini,  Ricardo 1 185 

Pierson.  DJ    1 169 

Pilman,  Dulsie 1172 

Pinnell,  Ronda 1 173 

Pinsky,  Michael  R 1 196 

Piotrowski,  A 1200 

Plevak,  David   1201 

Poll,  Kathy 1 160 

Potts,  Marianne 1 169 

Pranikoff,  T 1 198 

Pratt,  Nadine  1 169 

Purtz,  Edward  P 1186 

R 

Rankin,  N    1164 

Rasmussen,  Keith  G   1168 

Rau,  JL 1180  (2),  1181 

Reid,  Russell  T  1193  (2),  1195 

Reily,  Daniel  J 1168, 1206 

Renn,  Kathy 1 165 

Restrepo,  Ruben  D  1 180,  1 181 

Richards,  G   1201 

Richards,  Rodger 1200 

Riggi,  Vincent 1 196  (2),  1197 

Ritz.Ray  1184,  1196(2),  1197 

Rogers,  Mark   1 168, 1206,  1207 

Rollins,  Robert  J  1 169 

Ropelato,  Shari  1204 

Rosolowski,  Bonnie   1 1 74 

Rubin,  Bruce  K  1 181  (2) 

Russell,  GB 1 177 

S 

Salyer,  John  W 1160,  1 192,  1 193,  1202 

Santoro,  Michael 1 153,  1 160,  1 168 

Scholle,  Sarah 1 162 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1215 


Open  Forum  Author  Index 


Schroeder.  Darrell 1201 

Schultz,  Theresa  Ryan   1158  (2).  1159, 1173 

Schwartz.  Whitney  L   1160, 1178 

Scott,  Randy 1168,  1 185  1206,  1207 

Sestito.John   1153,  1160,  1168 

Shapiro.  Steven 1 200 

Shema.  Sarah 1 162 

Shreiner.  RJ 1 198 

Shulkin.  David   1153,  1 160,  1168 

Silva,  Fidel    1194 

Silver,  Patricia 1200 

Silvestri,  G 1170 

Simonton.  Susan  C   1 198 

Sivieri,  Emidio  M  1 179 

Slogic.  Scott    1173 

Smaldone.  Gerald  C   1 182  (2) 

Smith,  Brian  L 1 202 

Smith,  Edmond 1181 

Smith.  Kendra  M 1 178,  1 198  (2),  1206 

Snow.  M    1178,  1179 

Specht.  N  Lennard    1172 

Stanish.  Christine  W 1169 

Steinbach.  John 1156 

Stevens.  Victor  J  1152 

Stewart-Hockley,  Corie    1 163 

Stoddard,  Ronald 1157 

Stoller.JK  1162 

Strizek.  Sandra   1 165 

Stubbs.CR 1169 

T 

Tandon.  Ravi 1 182 

Tashiro.  Chikara  1 1 86 

Tasota,  Fred 1 196 

Taylor,  Jerome    1 195 

Tenaglia.  Christine  A  1170 

Thomas.  Shyni    1 195 

Thompson,  John   1 1 86,  1 1 87 

Thompson,  R 1200 

Thomsen.  George  1 194 

Tobin,  MJ   1182 

Toniolo.  Gabriella 1 206 


Totaro.J 1177 

Trivedi,  Jigish  D   1194  (2) 

Trocchio,  Marc  1 165 

Trotter,  Liz  Beth  1163 

V 

Vacca,  Anthony 1 1 63 

Vaccaro,  Jamie   1156 

vanStralen.  Daved 1206 

Volsko,  Theresa   1177,  1205 

Vukelic,  G 1200 

W 

Wagner,  Donald  I  1152 

Wagonseller,  Janette  M 1 182 

Wallace,  Jane    1 160,  1 161 

Wang,  Jia-Horng 1181 

Wang,  Peter 1205 

Ward.  Jeffrey 1201 

Waugh,  Jonathan  B 1158 

Weinert.  Mary 1202 

Weissman,  C 1 1 74 

Wemhoff,  Donna 1163 

Wenzel.  Arlene 1 168 

White,  K    1176 

Wiedemann,  HP   1 176 

Wilmouth.  Robert  J 1 169 

Wilson.  Barbara  G 1172  (2) 

Wilson.  Bradley  RA  1 152 

Wilson.  Sterling    1204 

Wise,  Constance  R   1198  (2) 

Y 

Ykoruk.  Regina 1 179 

Young,  Wang  Hsueh-fen   1 160 

Z 

Zapol,  Warren  M 1 185 

Zeck,  Robert  1 162 

Zhang.  Xiaoping 1 160.  1 161 

Zhu,  Y  1180 

Zibrak.JD  1174 

Zilber.  Anatoly  P 1179 

Zodda.J 1197 


1216 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


Sooner 
you'll  be  weaning 


or  later, 
liirn  off  the  vent. 

So  why  not  make  it  sooner? 

Weaning  protocols  that  use  capnography 
can  help  take  the  guesswork  out  of 
weaning  decisions. 

Considering  the  time,  resources,  and  quality-of-care 
issues  involved  in  weaning  ventilated  patients,  the 
implications  are  clear.  When  the  process  of  weaning 
patients  from  the  ventilator  is  arbitrary,  it  creates  variability 
that  can  lead  to  increased  costs  and  reduced  efficiency. 

There  is  an  alternative.  Close,  continuous  monitoring 
of  end-tidal  C02-as  part  of  a  weaning  protocol -provides 
timely  information  to  help 


With  the  Ultra  Cap  monitor,  the 
effects  of  ventilator  settings  can 
be  measured  breath  to  breath, 
rather  than  after  the  10-  to  20- 
minute  waits  associated  with 
blood  gas  analysis. 


you  gauge  your  patient's 
ability  to  be  weaned  off  the 
ventilator.  Instituting  a 
protocol  that  leads  to  fewer 
ABGs  and  reduced  ventilator 
time  per  patient  can  save 
money,  potentially  improve 
quality  of  care,  help  reduce 
MLOS,  and  make  bed 
utilization  more  efficient. 


Make  the  Ultra  Cap  monitor  a  part 
of  your  ventilator  weaning  process. 

Nellcor  Puritan  Bennett  can  help  you  integrate 
capnography  into  a  vital  and  effective  weaning  protocol. 
Take  advantage  of  our  extensive  training  and  support 
materials,  including  our  comprehensive  collection  of 
institutional  weaning  protocols.  And  you  can  use  our 
Ultra  Cap®  capnograph  and  pulse  oximeter  to  implement 
a  protocol  of  your  own. 

Because  when  it  comes  to  weaning  patients  off  the 
ventilator,  we  think  you'll  agree -the  sooner,  the  better. 

For  more  information,  contact  your  local  representative 
or  call  1-800-NELLCOR  or  510-463-4000.  (Call  our 
European  office  at  +31.73.426565  or  our  Asia/Pacific 
office  at +852.2529.0363.) 


NELLCOR 
PURITAN 
BENNETT. 


Ultra  Cap  is  a  trademark  of  Nellcor  Puritan  Bennett  Inc. 
©  1995  Nellcor  Puritan  Bennett  Inc.  All  rights  reserved. 


Convention  Exhibitors 


Exhibitors 

at  the  41st  Annual  Meeting  &  Exposition  of  the 
American  Association  for  Respiratory  Care 

December  2-5,  1995 
Orlando,  Florida 


Thousands  of  examples  of  respiratory  care  equipment  and  supplies  are  displayed,  discussed  and  demonstrated 

in  the  exhibit  booths  at  the  Annual  Meeting.  The  AARC  thanks  the  firms  that  support  the  Association  by  participating. 

(Exhibitors  confirmed  by  October  10,  1995  are  listed.) 

Exhibit  Hours 

Saturday,  December  2,  Noon-4  PM 

Sunday,  December  3,  1 1  AM-4  PM 

Monday,  December  4,  1 1  AM-4  PM 

Tuesday,  December  5,  1 1  am-3  pm 


Exhibitor 


Booth 


Exhibitor 


Booth 


A 

Ackrad  Laboratories,  Inc 1504 

Advanced  Lifeline  Services,  Inc 1045 

Advance  Newsmagazine/Merion  Publications,  Inc 1028 

Aequitron  Medical,  Inc 436 

AirSep  Corporation 545,  547 

Allen  &  Hanburys,  Division  of  Glaxo,  Inc 612 

Allergy  &  Asthma  Network/Mothers  of 

Asthmatics,  Inc 1249 

Allied  Healthcare  Products,  Inc 426 

Alphal  National  Association 1251 

Ambu,  Inc 521,523,525 

American  Biosystems,  Inc 1 19 

American  College  of  Chest  Physicians 1352 

American  HomePatient 1311 

American  Society  of  Electroneurodiagnostic 

Technologists,  Inc 1351 

AnaMed  International 929,931 

Anesthesia  Associates,  Inc 748 

Apria  Healthcare  Group 813 

Arbor  Health  Care  Company I  1  1 

ARC  Medical,  Inc 1233.  1235 

Asthma  &  Allergy  Foundation  of  America 1 347 

Astra  USA,  Inc 1344 


Automatic  Liquid  Packaging,  Inc 302 

AVL  Scientific  Corporation 536 

B 

B  &  B  Medical  Technologies,  Inc 952 

Ballard  Medical  Products 918,920 

Baxter  Healthcare  Corporation 1 102 

Bay  Corporation 1227.  1229 

BCI  International 910,912 

Becton  Dickinson  &  Company 452 

Bedfont  Scientific  USA I  142 

Bio-Logic  Systems  Corporation 548 

Bio-Med  Devices,  Inc 71  1,713 

Biomedical  Sensors 342.  344 

Bird  Products  Corporation 724 

Bivona  Medical  Technologies 230.  232 

Blairex  Laboratories.  Inc 1329 

Bluebonnet  Pharmaceutical  Sales 151 1 

Boston  Medical  Products.  Inc 446 

Breasy  Medical  Equipment  (US),  Inc 1320 

Bunnell  Incorporated 925,927 

Burdick,  Inc 716 

C 

CAIRE,  Inc 626 

California  College  for  Health  Sciences 527 


1218 


Risi'ikA  muY  Cari;  •  Noykmhhr  '95  Vol  40  No  1 1 


Convention  Exhibitors 


Exhibitor 


Booth 


Exhibitor 


Booth 


Center  Laboratories 1047 

Cerner  Corporation 247 

Chad  Therapeutics,  Inc 1505 

Ciba  Corning  Diagnostics  Corporation 902 

Clement  Clarke 1325 

CNS.Inc 330 

Consentius  Technologies 445 

Core-M,  Inc 1405 

Creative  Biomedics 1330 

Criticare  Systems.  Inc 1218 

D 

Dale  Medical  Products,  Inc 914 

DataStar  Education  Systems  &  Services,  Inc 1333 

Delmar  Publishers/ITP 105 

DeVilbiss  Health  Care,  Inc 1010,  1012.  1014 

Dey  Laboratories 246,  248 

DHD  Diemolding  Healthcare  Division 815,  817,  819 

Diametrics  Medical,  Inc 650,  652 

Drager,  Inc 526 

E 

Encyclopaedia  Britannica  North  America 343 

Environmental  Tectonics  Corporation 139.  141 

Epic  Medical  Equipment  Services,  Inc 238 

EPM  Systems 241,  243 

Erich  Jaeger  GmbH 334 

Erie  Medical 749 

Evergreen  Pharmacy  Services 949 

F 

F.A.  Davis  Company/Publishers 851 

Ferraris  Medical,  Inc 531 

Fisher  &  Paykel  Healthcare 818,820 

Fisons  Pharmaceuticals 1034 

Florida  Hospital 143 

Focus  Publications,  Inc 109 

Futuremed  America,  Inc 1018 

G 

GCX  Corporation 549,551 

Genentech,  Inc 1313,  1315 

General  Biomedical  Service,  Inc 208 

General  Physiotherapy,  Inc 847 

Gibeck,  Inc 133,  135,  137 

The  Gideons  International 1502 

Golden  Care,  Inc 347 

H 

Hamilton  Medical,  Inc 1232 

Hans  Rudolph,  Inc 443 

Healthdyne  Technologies,  Inc 1312 

Health  Educator  Publications,  Inc 202 

HealthScan  Products,  Inc 1310 

Hill-Rom 449,451 

Horizon/CMS  Healthcare,  Inc 1332 

Hospitak,  Inc 917,  919 


HR  Incorporated 1500,  1501 

Hudson  RCI 502 

Hy-Tape  Corporation 214 

I 

I-Stat  Corporation 338 

I.V.  League  Medical 448 

ICN  Pharmaceuticals,  Inc 1050,  1052 

Impact  Medical  Corporation 224 

Indiana  University 1349 

Infrasonics,  Inc 1110 

IngMar  Medical 1323 

Instrumentation  Industries,  Inc 517,  519 

Instrumentation  Laboratory 1208 

InterMedway 529 

International  Biomedical 809,  81 1 

Invacare  Corporation 320 

Invivo  Research,  Inc 552 

IPI  Medical  Products 611,  613 

J 

J  H  Emerson  Company 752 

Jackson  Memorial  Hospital 1512 

Jones  Medical 628 

K 

Kendall  Healthcare  Products  Corporation 1147,  1149 

King  Systems  Corporation 913,  915 

Kirk  Specialty  Systems 615 

K.V.A.,  Inc 550 

L 

Laboratory  Data  Systems,  Inc 1506,  1507 

Lakeland  Regional  Medical  Center 349 

Laerdal  Medical  Corporation 651 

LeMans  Industries  Corporation 1331 

LIFECARE  International,  Inc 842 

Linear  Tonometers,  Inc 1321 

Lippincott-Raven  Publishers 123 

Liquid  Carbonic 718,720 

LM  Software 852 

M 

Maginnis  &  Associates 935 

Mallinckrodt  Medical,  Inc 1118 

MarkCare  Medical  Systems,  Inc 348 

Marquest  Medical  Products,  Inc 942 

Martell  Medical  Products,  Inc 712,  714 

MBNA  Marketing  Systems,  Inc 236 

M.  C.  Johnson  Co.,  Inc 352 

MedCare  Medical  Group,  Inc 1 146 

Medical  Graphics  Corporation 924 

Medical  Plastics  Laboratory,  Inc 1336 

Medical  Taping  Systems,  Inc 951 

MEDIQ/PRN  1022,  1024 

Mediserve  Information  Systems 617,  619 

Medisonic  USA,  Inc 1337 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1219 


Convention  Exhibitors 


Kxhibitor 


Booth 


Exhibitor 


Booth 


Medox  Corporation 1 150.  1 152 

Mercury  Medical 544.  546 

MES 345 

Methapharm,  Inc 1335 

Michigan  Instruments 121 

Micro  Direct.  Inc. /Micro  Medical  Limited 101.  103 

MMCA/MistyOx 642 

Monaghan  Medical  Corporation 1 128 

Mosby 1016 

MSA 622,624 

MultiSPIRO.  Inc 1503 

N 

NASCO 1510 

National  Board  for  Respiratory  Care 1250,  1252 

National  Committee  for  Clinical 

Laboratory  Standards 1350 

National  Heart.  Lung,  and  Blood  Institute 1051 

National  Library  of  Medicine 1151 

Nellcor  Puritan  Bennett 802.  1302.  1303,  1305 

Neonatal  Intensive  Care 649 

Newport  Medical  Instruments,  Inc 742 

Nicolet  Biomedical.  Inc 921,  923 

Nidek  Medical  Products.  Inc 450 

NMCHomecare 933 

Nonin  Medical.  Inc 945,  947 

Nova- VentRx,  Inc 1032 

Nova  Biomedical 634,  636.  638 

Nova  Health  Systems,  Inc 747 

Novametrix  Medical  Systems.  Inc 1 1 34 

Nth  Systems.  Inc 422 

Nutec  Medical  Products,  Inc 147 

O 

Ohmeda 824 

Omron  Healthcare 648 

Orlando  Regional  Healthcare  System 216 

Ottawa  University  Kansas  City 630 

Oxigraf 1248 

P 

PalcoLabs 1030 

Pall  Biomedical  Products  Company 501,  503,  505 

PARI  Respiratory  Equipment,  Inc 1 17 

Passy-Muir.  Inc 1020 

Peace  Medical,  Inc 507 

Pegasus  Research  Corporation 849 

Percussionaire  Corporation 950 

Perry  Baromedical 249,251 

Pfizer,  U.S.  Pharmaceuticals  Group,  Pfizer 302 

Pneutronics  Division  Parker  Hannifin 

Corporation 1334 

Posey  Company 751 

Precision  Medical.  Inc 1 13 

Presbyterian  Hospitals  of  New  Mexico 245 


Pro-Tech  Services,  Inc 444 

Professional  Medical  Products,  Inc 812.  814 

Protocol  Systems.  Inc 1 144 

Pryon  Corporation 1307,  1309 

Pulmo02 1242 

Pulmonary  Data  Service  Instrumentation 916 

Pulmonox  Research  &  Development 

Corporation 212 

R 

Racal  Health  &  Safety.  Inc.  Medical  Division 1148 

Radiometer  America,  Inc 512 

ResCare,  Inc 149,  151 

Respiratory  Care  Services,  Inc 948 

Respiratory  Distributors,  Inc 1048 

Respironics.  Inc 412 

RNA  Medical 937 

Ross  Products  Division  of  Abbott  Laboratories 816 

RT  Magazine/Curant  Communications 1042 

Rusch,  Inc 1340 

S 

S  &  M  Instrument  Company 220.  222 

Salter  Labs 618.620 

Schiller  America,  Inc 447 

SensorMedics  Corporation 730 

Servomex  Company,  Inc 647 

Seven  Harvest  International 350 

Sherwood  Medical 533,535 

Siemens  Medical  Systems, 

Electromedical  Group 402 

Sievers  Instruments.  Inc 351 

Sleep  Sciences.  Inc 346 

Smiths  Industries  Medical  Systems.  Inc 1202 

Sontek  Medical.  Inc 1026 

SpaceLabs  Medical,  Inc 1041,  1043 

Spegas  Industries 252 

SUMMIT  Interactive  Software,  L.C 210 

Sundance  Rehabilitation  Corporation 1345 

Sunnydale  Industries.  Inc 240 

Superior  Products,  Inc 1046 

Symphony  Respiratory  Services 1 224 

T 

Teledyne  Brown  Engineering 204.  206 

Telefactor  Corporation 1 15 

Tenet  Information  Services.  Inc 1036.  1038 

Theracare 1403 

TheraTx,  Inc 107 

3M  Pharmaceuticals 715 

Transitional  Hospitals  Corporation 1231 

Transtracheal  Systems.  Inc 909,  91 1 

U 

Unicor,  Inc 850 

Universal  Hospital  Services 129,  131 


1220 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


Convention  Exhibitors 


Exhibitor 


Booth 


Exhibitor 


Booth 


University  Healthsystem  Consortium  Services 

Corporation 1049 

University  of  Rochester/Strong  Memorial  Hospital 848 

University  of  Texas  Medical  Branch  at  Galveston 234 

University  of  Virginia  Medical  Center 750 

UPC  Health  Network 1401 

US  Army  Recruiting  Command 242,  244 

V 

Vacumed 537 

Victor  Medical  Products 1339 

Vitalograph,  Inc 1508,  1509 

Vital  Signs,  Inc 308 

VORTRAN  Medical  Technology,  Inc 1327 


W 

W.B.  Saunders  Company 646 

W.T.  Farley.  Inc 1328 

Warren  E  Collins,  Inc 520 

Washington  Hospital  Center 250 

Western  Medica 717,719 

Western  Michigan  University 1343 

WestMed,  Inc 218 

Williams  &  Wilkins/Medi-Sim 1317 

Y 
Yale-New  Haven  Hospital 1301 

Z 
Zymed  Medical  Instrumentation 632 


Respiratory  Care  •  November  "95  Vol  40  No  1 1 


1221 


Notices 


Notices  of  competitions,  scholarships,  fellowships,  examination  dates,  new  educational  programs,  and  the  like  will  be  listed  here  free  of 
charge.  Items  for  the  Notices  section  must  reach  the  Journal  60  days  before  the  desired  month  of  publication  (January'  1  for  the  March  issue. 
February  1  for  the  April  issue,  etcl.  Include  all  pertinent  information  and  mail  notices  to  Respiratory  Care  Notices  Dept.  1 1030  Abies 
Lane.  Dallas  TX  75229-4593. 


The  National  Board  for  Respiratory  Care — 1996  Examination  Dates  and  Fees 


Examination 


Examination  Date 


Examination  Fee 


CRTT  Examination 


RRT  Examination 


CPFT  Examination 
RPFT  Examination 


Perinatal/Pediatric 
Respiratory  Care 


March  9,  1996 

Application  Deadline:  January  1,  1996 

July  20,  1996 

Application  Deadline:  May  1,  1996 

November  9,  1996 

Application  Deadline:  September  1.  1996 

June  1,  1996 

Application  Deadline:  February  1,  1996 


December  7,  1996 

Application  Deadline:  August  1,  1996 

June  1,  1996 

Application  Deadline:  April  1,  1996 

December  7,  1996 

Application  Deadline:  September  1,  1996 

March  9,  1996 

Application  Deadline:  November  1,  1995 


$  90  (new  applicantl 

60  (reapplicant) 

100  (new  applicant) 

60  (reapplicant) 

100  (new  applicant) 

60  (reapplicant) 

100  Written  only  (new  applicant) 

60  Written  only  (reapplicant) 

110  CSE  only  (all  applicants) 

210  Both  (new  applicant) 

170  Both  (reapplicant) 

110  (new  applicant) 

80  (reapplicant) 

160  (new  applicant) 

130  (reapplicant) 

160  (new  applicant) 

130  (reapplicant) 


For  information  about  other  services  or  fees,  write  to  the 
National  Board  for  Respiratory  Care,  8310  Nieman  Road,  Lenexa  KS  66214,  or  call  (913)  599-4200. 


United  Statei  Postal  Service 
Statement  of  Ownership,  Management, 

(Requ, 


nd  Circulation 


>l  cc    I'sNs 


2.  Publication  Number  (1098-9142 

4.  Issue  Frequency  Momhly 

6.  Annual  Subscription  Price:  $65  00 


TX 


i.  Publication  Title  Respiratory  Care 

3.  Filing  Dale    10/4/94 

5.  No.  of  Issue  I'uMislied  Annually   Twelve 

7.  Complete  Mailing  Addles-  ul  Known  Office  of 
Daedalus  Enlerprises.  Inc..  1 1030  Abies  Lane.  Dallas,  Dallas  Co..  TX  75229-4593 

8.  Complete  Mailing  Address  ol  Headquarters  or  General  Business  Office  of  Publisher 
Daedalus  Enlerpnscs.  Inc  .  1 1030  Abies  Lane.  Dallas.  Dallas  Co..  TX  75229-4593 

9.  Full  Name-  and  Compleie  Mailing  Addiess  ul  I'ubli.hci    Id  Urn   .in,]  Managing  l.ditoi 
Publisher— Sam  Giordano,  MBA.  RRT,  Daedalus  Enlerprises.  Inc  .  1 1030  Abies  Lane.  I 
Dallas  Co  ,  TX  75229-1593 

Editor— Pal  Btougher.  RRT.  Daedalus  Enterprises,  Inc.  1 1030  Abies  Lane.  Dallas.  Dall; 
75229J593 

Managing  Editor— Ray  Masfcrrer.  RRT,  Daedalus  Enterprises.  Inc  .  1 1030  Abies  Lane,  Dallas. 
Dallas  Co.,  TX  75229-4593 

10.  Owner  American  Assoc  union  tin  Respitalory  (ate    1 103(1  Ahles  Lane.  Dallas.  Dallas  Co.,  TX 
75229-4593 

11.  K in .ss n  Biiiidlmldi.T..  Mung.igecs  and  llihi  i  Security  HuldiTs  (limine  in  Holding  I  Percent  or 
MoreofToi.il  Auimuit  id  11., ink  Mnngages,  m  ( ithei  Sc,  unties  None 

12.  The  purpose,  function,  and  nonprofit  slants  ul  ilns  .ac.ini'.itinii  and  ih,  iscnipt  si.iuis  lot  ledci.il 
income  laA  purposes  has  mil  changed  timing  (he  picceding  12  months 

13.  Publication  Name  Rcspirulory  Care 

14.  Issue  Date  forCiieululion  Data  Below  October 

15.  Extent  and  Nature  of  Circulation 

Average  No  ofCoptes  Actual  No  of  Copies 

Each  Issue  [luring         of  Single  Issue  Published 

Preceding  12  Months  Neatest  to  Filing  Date 


a.  Total  No  of  Copies  (Nc(  Press  Run! 

b.  Paid  and/or  Requested  Circulation 

1 1 » s.des  through  i  ii  Ul  I-  (  .iiiiri,  i  ii 

i2i  I'.ud  in  Rei|ucsted  Mail  Subscribers 

i    I '  '  ii  Paid  and/of  Requested  I  llrcul m 

il  1 1. 1  I  ii  inlnilion  by  Mall 

■    I  n     i I ii  I  inside  the  Mail 

I.  Tolal  Free  Distribution 

'illinium 
h   i  OBll     '"i  liisinbulcd 

II) Ofr.cc  Use.  Leftovers,  Spoiled 

12)  Rclum  from  News  Agcnls 
I.  Tout 


W.854 


30.7S1I 


/^C^A^'  A 


FACE  TO  FACE  WITH  CHANGE 


I  At  l   lOLAO  Willi!  HANI. I 


A  ARC  4 1  st  Annual  Convention  &  Exhibition 

Orlando.  Florida 

December  2-5,  1995 


Pre-registration  deadline  is  November  1 1,  1995. 

On-site  registration  begins  at  10  AM,  December  1,  1995 

at  the  Orange  County  Convention  Center. 

For  information,  call  (214)  243-2272 


1222 


Rksimratory  Car.-:  •  Noyi.mm-k  '95  Vol.  40  No  1 1 


1996  Call  for  Abstracts 


Respiratory  Care  •  Open  Forum 


The  American  Association  for  Respiratory  Care  and  its  sci- 
ence journal,  RESPIRATORY  CARE,  invite  submission  of  brief 
abstracts  related  to  any  aspect  of  cardiorespiratory  care.  The 
abstracts  will  be  reviewed,  and  selected  authors  will  be  in- 
vited to  present  posters  at  the  OPEN  FORUM  during  the  AARC 
Annual  Meeting  in  San  Diego.  California,  November  3-6  1996. 
Accepted  abstracts  will  be  published  in  the  October  1996  issue 
of  RESPIRATORY  Care.  Membership  in  the  AARC  is  not  re- 
quired for  participation. 

SPECIFICATIONS— READ  CAREFULLY! 

An  abstract  may  report  ( 1)  an  original  study,  (2)  the  eval- 
uation of  a  method  or  device,  or  (3)  a  case  or  case  series. 

Topics  may  be  aspects  of  adult  acute  care,  continuing  care/re- 
habilitation, perinatology/pediatrics,  cardiopulmonary  tech- 
nology, or  health-care  delivery.  The  abstract  may  have  been 
presented  previously  at  a  local  or  regional — but  not  nation- 
al— meeting  and  should  not  have  been  published  previous- 
ly in  a  national  journal.  The  abstract  will  be  the  only  evidence 
by  which  the  reviewers  can  decide  whether  the  author  should 
be  invited  to  present  a  poster  at  the  OPEN  FORUM.  Therefore, 
the  abstract  must  provide  all  important  data,  findings,  and 
conclusions.  Give  specific  information.  Do  not  write  such  gen- 
eral statements  as  "Results  will  be  presented"  or  "Significance 
will  be  discussed." 

Essential  Content  Elements 

Original  study.  Abstract  must  include  ( 1 )  Background: 
statement  of  research  problem,  question,  or  hypothesis;  (2) 
Method:  description  of  research  design  and  conduct  in  suf- 
ficient detail  to  permit  judgment  of  validity:  (3)  Results:  state- 
ment of  research  findings  with  quantitative  data  and  statis- 
tical analysis:  (4)  Conclusions:  interpretation  of  the  meaning 
of  the  results. 

Method/device  evaluation.  Abstract  must  include  ( 1 )  Back- 
ground: identification  of  the  method  or  device  and  its  intended 
function;  (2)  Method:  description  of  the  evaluation  in  suffi- 
cient detail  to  permit  judgment  of  its  objectivity  and  valid- 
ity; (3)  Results:  findings  of  the  evaluation;  (4)  Experience: 
summary  of  the  author's  practical  experience  or  a  lack  of  ex- 
perience; (5)  Conclusions:  interpretation  of  the  evaluation  and 
experience.  Cost  comparisons  should  be  included  where  pos- 
sible and  appropriate. 

Case  report.  Abstract  must  report  a  case  that  is  uncom- 
mon or  of  exceptional  educational  value  and  must  include  ( 1 ) 
Introduction:  Relevant  basic  information  important  to  under- 
standing the  case.  (2)  Case  Summary:  Patient  data  and  response, 
details  of  interventions.  (3)  Discussion:  Content  should  re- 
flect results  of  literature  review.  The  author(s)  should  have 
been  actively  involved  in  the  case  and  a  case-managing  physi- 
cian must  be  a  co-author  or  must  approve  the  report. 


Abstract  Format  and  Typing  Instructions 

Accepted  abstracts  will  be  photographed.  The  first  line  of 
the  abstract  should  be  the  title  in  all  capital  letters.  Title  should 
explain  content.  Follow  title  with  names  of  all  authors  (in- 
cluding credentials),  institution(s),  and  location.  Underline 
presenter's  name.  Type  or  electronically  print  the  abstract  sin- 
gle  spaced  in  the  space  provided  on  the  abstract  blank.  In- 
sert only  one  letter  space  between  sentences.  Text  submis- 
sion on  diskette  is  encouraged  but  must  be  accompanied  by 
a  hard  copy.  Identifiers  will  be  masked  (blinded)  for  review. 
Make  the  abstract  all  one  paragraph.  Data  may  be  submitted 
in  table  form,  and  simple  figures  may  be  included  provided 
they  fit  within  the  space  allotted.  No  figures,  illustrations,  or 
tables  are  to  be  attached  to  the  abstract  form.  Provide  all  au- 
thor information  requested  at  the  bottom  of  abstract  form.  A 
clear  photocopy  of  the  abstract  form  may  be  used.  Standard 
abbreviations  may  be  employed  without  explanation.  A  new 
or  infrequently  used  abbreviation  should  be  preceded  by  the 
spelled-out  term  the  first  time  it  is  used.  Any  recurring  phrase 
or  expression  may  be  abbreviated,  if  it  is  first  explained.  Check 
the  abstract  for  ( 1 )  errors  in  spelling,  grammar,  facts,  and  fig- 
ures; (2)  clarity  of  language;  and  (3)  conformance  to  these 
specifications.  An  abstract  not  prepared  as  requested  may  not 
be  reviewed.  Questions  about  abstract  preparation  may  be  tele- 
phoned to  the  editorial  staff  of  RESPIRATORY  CARE  at  (214) 
243-2272. 

Deadline  Allowing  Revision 

Authors  may  choose  to  submit  abstracts  early.  Abstracts 
postmarked  by  February  1 1,  1996  will  be  reviewed  and  the 
authors  notified  by  letter  only  to  be  mailed  by  March  22, 
1996.  Rejected  abstracts  will  be  accompanied  by  a  written 
critique  that  should,  in  many  cases,  enable  authors  to  revise 
their  abstracts  and  resubmit  them  by  the  final  deadline  (April 
28,  1996). 

Final  Deadline 

The  mandatory  Final  Deadline  is  April  28  (postmark).  Au- 
thors will  be  notified  of  acceptance  or  rejection  by  letter  only. 
These  letters  will  be  mailed  by  July  15,  1996. 

Mailing  Instructions 

Mail  (Do  not  fax!)  2  clear  copies  of  the  completed  abstract 
form,  diskette  (if  possible),  and  a  stamped,  self-addressed  post- 
card (for  notice  of  receipt)  to: 

Respiratory  Care  Open  Forum 

1 1030  Abies  Lane 

Dallas  TX  75229-4593 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


1223 


1996  Respiratory  Care  Open  Forum 

Abstract  Form 


13.9  cm  or  5.5" 


1 .  Title  must  be  in  all 
uppercase  (capital) 
letters,  authors'  full 
names  and  text  in 
upper  and  lower  case. 

2.  Follow  title  with  all 
authors'  names 
including  credentials 
(underline  presenter's 
name),  institution,  and 
location. 

3.  Do  not  justify  (ie, 
leave  a  'ragged'  right 
margin). 

4.  Do  not  use  type  size 
less  than  10  points. 

5.  All  text,  tables,  and 
figures  must  fit  into 
the  rectangle  shown. 

6.  Submit  2  clean  copies. 
This  form  may  be 
photocopied  if 
multiple  abstracts  are 
to  be  submitted. 


Mail  original  & 
1  photocopy 
(along  with  postage- 
paid  postcard)  to 

Respiratory  Care 
Open  Forum 

11030  Abies  Lane 
Dallas  TX  75229-4593 


Early  deadline  is 
February  11,  1996 

(postmark) 

Final  deadline  is 

April  28,  1996 

(postmark) 


Name  &  Credentials 


Mailing  Address 


Voice  Phone  &  Fax 


Name  &  Credentials 


Mailing  Address 


Voice  Phone  &  Fax 


American 

Association 

for 

Respiratory 

Care 

The  AARC  Human 
Resources  Survey: 
A  Study  of 
Respiratory  Care 
Human  Resources 
in  Hospitals 

Covers  a  wide  range  of  human  resource 

issues,  including  compensation,  numbers 

of  full-time  equivalents,  job  vacancy 

rates,  education,  credentialing,  and 

licensure.  Even  includes  information  on 

age,  sex,  and  years  of  experience.  Includes  comprehensive  summary, 

position  profiles,  salaries,  education,  experience,  credentials,  and  regional 

demographics.  Vacancies  are  inventoried.  6S  pages,  66  tables. 

Item  BK12  $35  ($50  nonmembers) 


A  Study  of 
Chronic  Ventilator 
Patients  in  the 
Hospital 

Chronic  ventilator-dependent  patients 
are  costing  American  hospitals  more 
than  $9  million  per  day  according  to 
this  Gallup  study  conducted  for  the 
AARC.  This  important  study  provides 
information  on  patients  who  depend  on 
life-support  systems;  why,  how,  and 
where  they  are  being  treated;  and  the 
cost  of  treatment.  47  pages,  9  tables,  12 
figures. 
Item  BK20  $25  ($50  nonmembers) 

A  Study  of 
Respiratory  Care 
Practice 

This  study  examines  the  practice  of 
respiratory  care  in  today's  health  care 
environment  and  how  hospital 
reorganization  is  affecting  the 
profession.  Includes  chapters  on  medical 
direction,  current  respiratory  care 
services,  nontraditional  services, 
respiratory  care  protocols,  and  hospital 
service  reorganization.  38  pages, 
34  tables,  15  charts. 
Item  BK17  $20  ($40  nonmembers) 


Orders  with  credit  cards  or  P.O.  numbers  may  call 
(214)  243-2272,  or  Fax  to  (214)  484-2720. 
If  ordering  by  mail,  send  coupon  to: 
AARC  Order  Department,  11030  Abies  Lane, 
Dallas,  Texas  75229-4593. 


. 

. 

American 

Association 

for 

Respiratory 

Care 

: 
I 

Policy  & 

Procedure 

Manual 


Policy  and 
Procedure 
Manual 

Save  time  and  money  by 

making  your  department 

more  efficient  with  the 

Policy'  and  Procedure 

Manual.  Its  130  pages  of 

policies  and  procedures 

cover  the  aspects  of 

administrative  and  clinical 

respiratory  care  for  both 

adult  and  pediatric  practice. 

Sections  on  administrative 

policies,  therapeutics,  clinical 

monitoring,  and  mechanical 

ventilation.  Standardized  formats  include  objectives,  indications, 

equipment,  policies,  contraindications,  troubleshooting,  procedures, 

hazards,  and  assessment  of  effectiveness. 

Item  BK6   $60  ($70  nonmembers) 


Respiratory 
Home  Care 
Equipment 


Respiratory  Home  Care 

Equipment  exclusively 

covers  home  care 

equipment  with  practical 

applications  and  charts  on 

oxygen  concentrators, 

liquid  units,  air 

compressors,  and  home 

care  ventilators.  An 

invaluable  book  for  the 

home  care  practitioner  and 

equipment  technician. 

Details  home  care  devices, 

cleaning,  disinfecting,  and 

monitoring  procedures  to 

minimize  infection.  Includes  guides  for  educating  staff  on 

equipment,  therapy,  patient  assessment,  and  safety.  Features 

procedures  for  gas  administration  and  monitoring  devices, 

humidifiers  and  nebulizers,  artificial  airways  and  resuscitators, 

respirators,  and  ventilators.  By  Steven  P.  McPherson.  Hardcover, 

192  pages,  141  illustrations,  6  tables. 

Item  BK7   $9  ($12  nonmembers) 


Order  Total 

$15  or  less 

UPS  Reg. 
3.25 

UPS  2nd  Day 

6.00 

UPS  Next  Day 
14.00 

$16  to  $30 

3.75 

800 

18.00 

$31  to  $50 

4.50 

11.00 

24.00 

$51  to  $75 

5.50 

1 1  no 

31.00 

$76  to  $100 

7.00 

16.00 

38  00 

$101  to  $125 

8.00 

19.00 

50  00 

$126  to  $150 

10.00 

22  00 

60.00 

-Y5 


□  Please  send 
Item 


me  the  items  I  have  indicated  below. 

Description  Quantity 


Price  Each       Total  Price 


Ship  via  UPS  a  Regular    □  2nd  Day    □  Next  Day 
Please  use  the  chart  to  the  left  to  calculate  shipping. 


Shipping . 

Merchandise 

TOTAL . 

□  Check  or  Money  Order  enclosed  payable  to  the  AARC 

□  Bill  me,  my  P.O.  No.  is 

□  Charge  to  my   c  Visa    □  MasterCard 

Card  # Exp.  Date _  Signature  X 

AARC  Member  # 

Institution  

Address 


Name 


.  City/State/Zip 


New  Products 
&  Services 


News  releases  aboul  new  products  and  services  will  be  considered  for  publication  in  this  section.  There  is  no  charge  for 
these  listings.  Send  descriptive  release  and  glossy  black  and  white  photographs  to  RESPIRATORY  CARE  Journal.  New 
Products  and  Services  Dept.  1 1030  Abies  Lane,  Dallas  TX  75229-4593. 


PORTABLE  ECG  SYSTEM.  Schiller 
America's  new  Cardiovit  AT-4  is  a 
portable  ECG  system  for  busy  medical 
practices.  According  to  Schiller,  the  new 
monitor  is  easy  to  use  with  standard  per- 
formance features  such  as  1 2-lead  ac- 
quisition, large  LCD  screen,  built-in 
rechargeable  battery,  and  printer.  The 
monitor  also  offers  noise-free  record- 
ings, pacemaker  detection,  and  data 
transmission.  Optional  features  include 
automatic  ECG  measurements,  adult 
and  pediatric  interpretation,  rhythm 
recording.  20-patient  memory,  and 
more.  For  information,  mention  RES- 
PIRATORY CARE  when  you  call  Schiller 
at  (800)  247-8775. 


ASTHMA  MEDICATION.  Key  Phar- 
maceuticals Inc  announces  a  new  once- 
a-day  asthma  medicine — UNI-DUR'-' 
(theophylline)  extended-release  tablets, 
for  relief  and  prevention  of  the  symp- 
toms of  asthma  and  reversible  bron- 
chospasm  associated  with  chronic  bron- 
chitis and  emphysema.  The  medicine  is 
available  in  4(X)-mg  and  600-mg  tablets. 


According  to  Key,  the  prescribed  dose 
may  achieve  consistent  serum  theophyl- 
line levels  for  24  hours.  For  patients  who 
metabolize  theophylline  more  rapidly 
UNI-DUR  can  be  taken  at  12-hour  in- 
tervals. For  information  about  indica- 
tions, side  effects,  and  contraindications, 
call  (800)  XUNIDUR  or  (800)  986- 
4387.  Please  mention  Respiratory 
Care  when  calling. 


Delivery  Vehicles.  H  &  H  Sales 
now  offers  Step  Saver  Oxygen  and 
DME  delivery  vehicles.  The  vehicles 
are  designed  for  the  transport  of  oxy- 
gen and  DME  cylinders.  According  to 
H  &  H.  the  vehicles  feature  a  new  curb- 
side  roll -top  door  for  easier  and  safer 
driver  access,  a  lift  platform  that  han- 
dles up  to  1,250  pounds,  and  durable 
treadplate  flooring  for  long  wear.  The 
vehicles  can  be  equipped  with  a  pres- 
sure cylinder  rack  that  accommodates 
H-cylinders,  a  selection  of  DOT  plac- 
ards. E-tracks.  and  gas  cylinder  kick- 
plates.  Supply  bins  and  steel  storage 
shelves  are  also  available.  For  more  in- 
formation about  chassis  choices  and 
other  options,  write  to  H  &  H  Sales 
Company  Inc,  Dept  RC,  PO  Box  686, 
Huntertown  IN  46748-0686.  Or  men- 
tion Respiratory  Care  when  you  call 
(800)551-9341. 


Free  Mass  Spec  Training  Bro- 
chure. A  brochure — Mass  Spec- 
trometry Fundamentals  Multimedia 
Training — illustrates  the  Savant  Au- 
diovisual Windows®-based.  multi- 
media training  program.  According  to 
Savant,  the  brochure  describes  the  pro- 


gram's unique  features:  tracking  indi- 
vidual test  results  and  study  history,  ani- 
mated graphics,  video,  and  sound  clips. 
The  full  package  contains  an  introduc- 
tion, 8  computer-based  training  modules, 
a  VHS  videotape,  training  guide,  and  a 
296-page  student  handbook.  To  receive 
a  brochure  or  a  demonstration  diskette, 
write  to  Savant  Audiovisuals  Inc,  Dept 
RC,  801  East  Chapman  Avenue,  PO 
Box  3670,  Fullerton  CA  92634,  or  call 
(800)  472-8268,  and  mention  Respi- 
ratory Care. 


COUPLINGS.  Colder  Products  Com- 
pany introduces  the  FFC  quick  coupling 
with  a  0.520  in.  bore  for  greater  flow 
capacity.  According  to  the  company, 
the  coupling  provides  double  the  flow 
of  similar  products.  The  new  coupling 
can  handle  temperatures  from  -40°  F 
(-40°  C)  to  280°  F  (137.8°  C),  repeat- 
ed autoclaving.  boiling  water,  and 
strong  oxidants.  The  couplings  may  be 
used  in  a  broad  range  of  applications 
including  agricultural  spraying  systems, 
cell  culture  and  fermentation,  cooling 
and  heating  lines,  pharmaceutical  ap- 
plications, and  waste  removal.  The  cou- 
plings are  available  in  panel-mount,  in- 
line, pipe-thread,  and  garden-hose 
thread  configurations  and  in  thread  sizes 
of  1/2  in..  3/4  in.  NPT.  3/4  in.  BSPT. 
and  3/4  in.  male  and  female  garden 
hose.  Hose  barb  end  fits  3/4  in.  l.D.  tub- 
ing. Write  to  Colder  Products  Com- 
pany. Dept  RC.  1001  Westgate  Drive, 
St  Paul  MN  55 1 1 4,  or  phone  (612)  645- 
009 1  for  more  details.  When  you  call, 
please  mention  RESPIRATORY  CARE. 


1226 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


Meet  the  VI.P.  Class  of  2012 


|gg|    ^ 


Witfi  fe  V.I.?.  Bird®  Infant-Pediatrk  Ventilator  System,  even  the  smallest 
patient  can  look  forward  to  a  very  healthy  future. 


The  V.I. P.  Bird'5'  offers  the  clinician  the  choice  of  eight 
separate  modalities  designed  specifically  to  meet  the 
critical  care  needs  of  neonatal,  infant  and  pediatric 
applications.  These  design  features  improve  patient 
comfort  and  accelerate  the  weaning  process. 

System  features  include: 


•  Total  flow  synchrony 

•  Leak  compensation 

•  Variable  pressure  support  termination 

•  Measured  and  displayed  volumes 

•  Termination  sensitivity 

•  Real  time  graphics  and  trends 


Your  Very  Important  Patient's  healthy  future  begins 
with  the  VI.P.  Bird®. 


>i'j 


Certificate  No.  FM  31692 
ISO  9001  /  EN  46001 


Call  your  Bird  dealer  or  ^=  =^=^=  ^=^=  ^= 

1  800  328  4139  MM ^^4 MM 

for  more  information.  JKt^r^fh.  J ^M.^Mr 

Circle  1 27  on  reader  service  card  B'RD  PR°DUCTS  CORPORA  TION 

circle  iz/  on  reader  service  cara  A  Therm  Eleclron  company 

Visit  AARC  Booth  724  in  Orlando  Palm  Springs,  California  •  6I9. 778.7200 

The  Breath  of  Technology 


New  Products  &  Services 


Image  &  Record  Cart.  Vangard 

Systems  Inc  introduces  a  transport  cart 
that  accommodates  radiographs  and 
medical  records.  Each  cart  is  equipped 
with  a  special  wheel  system  designed  for 
use  on  various  floor  surfaces.  Vanguard 
claims  that  the  cart  is  easy  to  push  or  pull 
and  is  specifically  designed  for  use  in  the 
hospital  environment.  The  cart  contains 
several  divided  shelves  and  is  made  of 
steel.  In  addition,  a  retractable  writing 
surface  is  available.  For  details,  write  to 
Vangard  Systems  Inc,  Dept  RC,  25 100 
Euclid  Avenue,  Cleveland  OH  44 1 1 7, 
or  call  (216)  289-0400.  Please  mention 
Respiratory  Care  when  calling. 


Emergency  device  approved. 

CPR  Medical  Devices  Inc  announces 
that  the  Oxylator™  EM- 100  has  re- 
ceived FDA  section  510(K)  clearance. 
According  to  the  company,  the  Oxylator 
delivers  oxygen  to  patients  in  emer- 
gency respiratory  conditions.  A  sens- 
ing chamber  with  a  single  oscillating 
component  enables  the  device  to  re- 
spond to  the  patient's  inspiratory  and 
expiratory  phases,  and  allows  the  tech- 
nician to  receive  instant  feedback  to  as- 
sess the  nature  of  respiratory  emergency. 
The  device  is  classified  as  Class  II. 


Write  to  CPR  Medical  Devices  Inc, 
Dept  RC,  81  Mack  Avenue  Scarbor- 
ough Ontario  MIL  1 M8  Canada.  Don't 
forget  to  mention  RESPIRATORY  CARE 
when  you  call  (416)  691-2669. 


Medical  International  Research,  Dept 
RC,  Via  Macerata  24,  00176  Rome 
Italy,  or  fax  ++39/6/93.43.934. 


Syringe  &  Calibration  Service. 

Pulmonary  Data  Service  Instrumentation 
Inc  introduces  a  calibration  syringe  with 
an  aid  for  creating  controlled-flow  ranges 
as  required  for  spirometers  used  for  Social 
Security  disability  testing.  According  to 
the  company,  the  syringe  uses  a  patent- 
pending  technology  for  maintaining  a  con- 
sistent output  at  the  specified  flow  ranges. 
The  company  also  offers  a  calibration  ser- 
vice for  standard  3-liter  syringes  used  for 
calibrating  PFT  equipment.  Both  the  sy- 
ringe and  the  calibration  service  provide 
volumetric  accuracy  traceable  to  the  Na- 
tional Institute  of  Standards  and  Tech- 
nology. For  more  information,  call  (800) 
574-PDSI.  Please  mention  RESPIRATORY 
Care  when  you  call. 

SPIROMETER.  Medical  International 
Research  launches  the  Spirobank,  a 
pocket-sized,  multifunctional  spirom- 
eter. According  to  the  manufacturer,  the 
Spirobank  is  a  unique  combination 
spirometer  that  functions  in  3  modes. 
The  Personal  Mode  allows  for  at-home 
spirometry  and  can  track  the  variabil- 
ity of  FEV  |  and  FEF  as  well  as  provide 
messages  that  compare  current  mea- 
surements with  the  patient's  personal 
best.  The  Doctor  Mode  measures  more 
than  20  pulmonary  functions  and  cal- 
culates repeatability  and  test  accept- 
ability indices.  By  using  the  Online 
Mode,  the  portable  spirometer  and  a  per- 
sonal computer  become  a  full  diagnostic 
laboratory.  For  information,  write  to 


Nasogastric  Tube  Holder.  MC 

Johnson  Co  Inc  releases  a  holder  for  na- 
sogastric tubes,  nasal  feeding  tubes,  and 
oxygen  cannulas.  The  NG  Secure™  can 
hold  multiple  tubes  without  additional 
tape  or  discomfort  to  the  patient,  the 
company  claims.  The  holder  is  hy- 
poallergenic.  features  a  reusable  flap  that 
eliminates  the  need  for  constant  retap- 
ing.  In  addition,  the  holder  helps  prevent 
pressure  sores  and  discomfort.  For  a  free 
sample  and  more  information,  mention 
RESPIRATORY  Care  when  you  call 
(800)553-8483,  or  write  to  MC  John- 
son Co  Inc,  Dept  RC.  4292  Corporate 
Square  Suite  C.  Naples  FL  33942-4753. 


Sharps   Management  System. 

BioSafety  Systems  announces  the  ad- 
dition of  the  Isolyser  SMS — a  sharps 
management  system.  BioSafety  claims 
the  system  uses  a  phenolic  derivative  so- 
lution to  disinfect  sharps  at  the  point  of 
generation.  By  adding  water  and  shak- 
ing the  full  container,  an  exothermic  re- 
action takes  place  to  solidify  the  con- 
tents into  a  polymerized  gel  that  may  be 
discarded  as  decontaminated  waste.  For 
a  catalog  or  more  information,  call  (800) 
42 1  -6556.  Don't  forget  to  mention  RES- 
PIRATORY Care. 


1228 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


f 


fo  San  Ditfo,  Cat ffomto 
«mf  Ifct  AAJK  AmmmI  M«« 


•  San  Diego,  California—a  picture-perfect  vacation  destination  where 
you  can  explore  the  ocean  depths  of  Sea  Worldf  go  wild  at  the 
world  famous  San  Diego  Zoo,  head  south  of  the  border  to  Tijuana, 
kick  back  and  enjoy  the  sun-bleached  beaches  of  Mission  Bay,  and 
partake  of  the  exciting  AARC  Annual  Meeting. 

To  picture  yourself  in  this  exciting  vacation  package,  circle  number  1 00 
on  the  reader  service  card  in  this  issue,  request  any  other  material 
you  might  like  to  receive,  complete  the  requested  information,  and  mail 
the  card. 

Your  picture-perfect  vacation  includes:    / 

■  Round-trip  air  transportation  to  San  Diego  for  two,  November  2-6,  1996 

■  4  nights  hotel  accommodations,  including  room  tax,  at  a  selected 
/  '  San  Diego  hotel,  November  2-5,  1996 

■  Admission  to  the  AARC  Annual  Meeting,  November  3-6,  1996 
(Sunday-Wednesday) 


Official  Rules:  No  purchase  necessary.  To  enter,  circle  number  100  on  the  reader  service 
card  In  this  issue,  request  any  other  material  you  might  like  to  receive,  then  complete 
your  name,  address,  telephone  number,  and  other  information  requested.  Mail  the 
postage-paid  card  to  AARC  Publications,  P.O.  Box  11605,  Riverton,  NJ  08076-7205. 
Entries  must  be  received  no  later  than  midnight  September  1 ,  1996.  Prize  is  valid  for 
travel  only  November  2-6,  1995.  Entrants  must  be  at  least  18  years  of  age.  Illegible 
entries  will  be  disqualified.  AARC  Times  and  Respiratory  Care*  are  not  responsible  for 
late,  lost,  damaged,  or  misdirected  mail.  The  winner  will  be  selected  in  a  random 
drawing  at  Daedalus  Enterprises,  11030  Abies  Lane,  Dallas,  TX  75229-4593  on  or  about 
September  5,  1996.  Federal,  state,  and  local  taxes  are  not  included  in  prize  package. 
Meals,  gratuities,  and  all  other  expenses  not  specified  herein  are  the  responsibilities 
of  the  winner.  Void  where  prohibited  by  law,  and  all  federal,  state,  and  local  laws  apply. 
NO  substitution  for  prizes.  Prizes  are  not  transferable  and  are  not  redeemable  in  cash. 
The  winner  will  be  notified  by  mail  or  telephone. 


Calendar 
of  Events 


Not-for-profit  organizations  are  offered  a  free  advertisement  of  up  to  eight  lines  to  appear,  on  a  space-available  basis,  in  Calendar  of  Events  in 
RESPIRATORY  CARE.  Ads  for  other  meetings  are  priced  at  $5.50  per  line  and  require  an  insertion  order.  Deadline  is  the  20th  of  the  month  two 
months  preceding  the  month  in  which  you  wish  the  ad  to  run.  Submit  copy  and  insertion  orders  to  Calendar  of  Events.  RESPIRATORY  CARE. 
1 1030  Abies  Lane,  Dallas  TX  75229-4593. 


AARC  &  AFFILIATES 

January  26, 1996  in  Austin,  Texas.  The  TSRC  announces 
its  Annual  Winter  Forum  at  the  Marriott  Hotel  on  1 1th  Street. 
Contact  the  TSRC  Executive  Office  in  Dallas  at  (214)  680- 
2455,  or  contact  Mimi  Bartel  in  Houston  at  (713)  746-5354. 

February  20-23, 1996  in  Reno,  Nevada.  The  American 
Lung  Association  (ALA)  of  Nevada  and  the  NSRC  host  the 
15th  Annual  High  Sierra  Critical  Care  Conference  at  the 
Peppermill  Hotel-Casino.  The  conference  covers  critical 
care  topics  in  adult,  pediatric,  and  neonatal  medicine.  Con- 
tact Sherry  Landis,  ALA  of  Nevada,  PO  Box  7056,  Reno 
NV  89510. 

OTHER  MEETINGS 

December  1  in  Chapel  Hill,  North  Carolina.  The  respi- 
ratory care  and  nursing  departments  of  University  of  North 
Carolina  (UNC)  Hospitals  and  the  UNC  School  of  Medicine 
present  the  3rd  Annual  Critical  Care  Symposium.  Contact 
the  Office  of  Continuing  Education  at  (919)  962-21 18,  fax 
(919)962-1664. 


March  28-30, 1996  at  Big  Sky,  Montana.  The  American 
Lung  Association  (ALA)  of  Montana  announces  the  15th  An- 
nual Big  Sky  Pulmonary  &  Critical  Care  Medicine  Confer- 
ence. Contact  the  ALA  of  Montana.  825  Helena  Ave,  Hele- 
na MT  59601,  (406)  442-6556,  fax  (406)  442-2346. 

April  9-15, 1996  in  Miami,  Florida.  The  Ventilation  As- 
sisted Children's  Center  (VACC)  of  Miami  Children's  Hos- 
pital Division  of  Pulmonology  announces  its  free  camp  for 
ventilation-assisted  children  and  their  families.  Activities 
include  field  trips,  swimming,  games,  arts,  and  crafts.  The 
application  deadline  for  overnight  campers  is  January  5.  1996. 
Contact  Director  Moises  Simpser  or  Coordinator  Cathy  Klein, 
VACC,  Division  of  Pulmonology,  Miami  Children's  Hos- 
pital. 3200  SW  60th  Ct,  Suite  203.  Miami  FL  33155-4076, 
(305)  662-VACC,  fax  (305)  663-8417. 

September  18-21, 1996  in  San  Jose,  Costa  Rica.  The  Costa 
Rica  Society  for  Respiratory  Therapy  presents  the  2nd  Latin 
America  Congress  and  Caribbean  Congress  for  Respiratory 
Therapy.  Contact  Lie  Carlos  E  Pereira  Hidalgo,  Apartado  1 84- 
1017,  San  Jose  2000,  San  Jose  Costa  Rica,  (506)  232-8310, 
fax  (506)  232-7786. 


Mark  Your  Calendars! 


Future  AARC  Conventions 


December  2-5, 1995 
Orlando,  Florida 

November  3-6, 1996  (Sunday  -  Wednesday) 
San  Diego,  California 

December  6-9, 1997 
New  Orleans,  Louisiana 

November  7-10, 1998 
Atlanta,  Georgia 


[230 


Respiratory  Carp:  •  Novpmbpk  '95  Vol  40  No  l  I 


rCH  IT  EKERCI 

nuLMm 

•mmm  MR290-- 

SINGLE  USE  flUTOFEED  HUM1D1FICOTIOH  CHAMBER^ 
UV IRRODIRTED  Refer  to  instruct^--  : 

'■'  w<x*mm  p«»  f  awrrota  of  ISO  i/nin     * 


The  MR290  is  Fisher  &  Paykel's  most  advanced 
water-feed  chamber  yet,  designed  to  maintain  its 
self-control  under  even  greater  pressure. 

With  the  help  of  our  newly  developed  dual  float 
mechanism,  the  MR290  simply  and  effectively 
regulates  its  own  water  level.  And  the  MR290  is 
transparent  to  let  you  see  its  self-control  in  action  and 
check  its  water  level  at  a  glance. 

Just  as  efficient  and  reliable  as  the  rest  of  the 


Fisher  &  Paykel  range,  the  MR290  is  even  easier  to  use. 
Find  out  just  how  easy  by  trying  out  an  introductory 
pack  of  10. 

For  more  information,  contact  your  local  Baxter 
representative  on  1-800-321-3832  toll-free,  or  drop  into 
Booth  No.  818/820  at  the  AARC  Conference  in  Orlando. 

Fisher  &  Paykel 


HEALTHCARE 


Fisher  &  Paykel  Healthcare:  25  Carbine  Road  P.O.  Box  14-348  Panmure.  Auckland  NEW  ZEALAND  Tel:  +64-9-574  0100  Fax:  +64-9-574  0158. 

Circle  128  on  reader  service  card 


IF  THIS    PAINT 

SHAKERWAS  CAPABLE 

OF  HAVING  A  PULSE, 

OUR  NEW  DIGITAL 

OXIMETERS  WOULD 

BE  CAPABLE  OF 
READING   IT. 


By  applying  digital  technology  to  oximetry,  Criticare  enables  you  to  get  accurate, 
reliable  readings  in  situations  that  before  have  proven  difficult  or  impossible.  The 
presence  of  low  perfusion,  motion  artifact  or  ambient  noise  no  longer  results  in  a 
constant  series  of  irritating,  monitor-related  alarms  and  greatly  reduces  the 
amount  of  time  you  '11  stand  in  front  of  a  monitor  with  a 

frustrated  look  onyourface  ^^^^^^^         muttering  colorful  exple- 

tives.  Whether  it's  a  clinical  ^w  setting,  sub-acute,  general 

Jloor,  pre-hospital  or  transport  area,  the  new  digital  oximeters  from  Criticare 
will  not  only  perform,  they  will  perform  with  consistency  and  credibility.  At 
Criticare,  it's  fust  our  way  of  shaking  up  the  world  oj  oximetry.  For  more 
information  call  1-800-458-4615  or  write  Criticare  Systems,  Inc.,  P.O.  Box 
26556,  Milwaukee,  Wisconsin  53226.  CSI-INTERNATIONAL  GmbH. 
Gotzenmiihlweg  66,  D-61350  Bad  Homburg,  Germany.  Tclefon:  011-49- 

re/  CRITICARE 

6172-32052.  Telefax:  011-49-6172-52055.    ■»#      systems,     inc. 


.  %. 


Circle  126  on  rea 
Visit  AARC  Booth  12 


An  Innovative  Solution 


r5P' 

I    iJ 

u 

WfKfvm 

^^^^^^3[s3j^j  ^H 

1PH 

■    '•^Wp*"^^^ 

"^L"'JB 

HLD^i 

•v^s 

f  11 

■  ^^^^E 

1    } 

v  /J* 

^^p-             ^ai 

Wk —r 

SHHHr  *«• 

77m?  New  TruZone™  Peak  Flow  Meter 
True  Versatility! 


Monaghan  Medical  Corporation 

manufacturers  of  the  AeroChamhef  Family  of  Aerosol  Holding  Chambers. 

For  more  information,  call  or  write: 

Monaghan  Medical  Corporation,  PO  Box  2805,  Pittsburgh,  NY   12901-0299 
TruZone™  PFM  Customer  Service  1-800-833-9653  EXT  #  208 


In  Peak  Flow  Monitoring 


A 


Peak  Flow  Meter 

TRU^ZONE 

Logarithmic  Scale 

Simplifies  reading  of  Peak  Expiratory  Flow  Rate  (PEFR) 
One  unit  satisfies  the  standards  for  both  children  and  adults 

Cost  Effective 

One  peak  flow  meter  for  all  users 

One  peak  flow  meter  for  asthma  or  emphysema  patients 

ColorZone™  Tapes 

True  zones  as  suggested  by  the  NAEP 
Actual  zones,  not  end  points,  are  easily  identified 
Facilitates  customization  as  suggested  by  NAEP 
Color  Zones™  are  transparent  -  indicator  is  easy  to  see 

Internal  Indicator 

Reliable  and  accurate  readings  - 
indicator  is  enclosed  and  tamper  proof 

Transparent  body  of  the  TruZone™ 
can  be  held  in  any  manner 

Prevents  inadvertent  changes  to  the 
PEFR  readings 

User  friendly  -  facilitates  patient 
compliance 

Unique  Body  Shape 

Comfortable  to  hold 

Ready  for  convenient  use  at  all  times 

Nothing  to  unfold  or  assemble 

Fits  in  pocket  or  purse  The  TruZone™  PFM  meets  all  NAEP  standards. 


TruZone™  PFM 
shown  actual  size 


monaghan     R*^0# 


Circle  113  on  reader  service  card 
Visit  AARC  Booth  1128  in  Orlando 


Sponsors  of  AARC'S 
Peak  Performance  USA  Program 


ENITH  JRL 


ill 

,■>"■■■■■ 


WARNING:  Insufficient  Medical  Research 
Can  Be  Hazardous  To  Your  Health 


Too  many  Americans  are  suffering  and  dying 
needlessly  because,  as  a  nation,  we  don't  invest 
enough  in  medical  research. 

That's  why  former  Surgeon  General  C.  Everett 
Koop  is  joining  RESEARCH  (AMERICA,  an 
alliance  for  discoveries  in  health,  in  making 
this  simple  request: 


Take  action!  Let  your  voice  be  heard  in  support 
of  medical  research  as  the  nation's  No.  1 
national  priority. 

CALL  1  800-363  CURE  for  information  on  how 
to  deliver  your  WARNING. 

Research^  America 


y7/w  CdUozial aooaxd o/ Jneaphatiou/  Gate pmenfo... 

Clinical  Research — 
An  Imperative  for  Respiratory  Care 

As  in  past  years,  the  1995  Research  Symposium  is  designed 

to  meet  your  needs  as  a  respiratory  care  researcher  whether 

you  are  just  beginning  or  are  accomplished.  The  program  is  a 

mix  of  theory  and  application... 

Introduction  and  Overview 

James  K  Stoller  MD 

Identifying  a  Clinical  Question  and  Formulating  a  Hypothesis 

Shelley  Mishoe  PhD  RRT 

A  Vignette:  What  Is  a  Null  Hypothesis? 

Dean  Hess  PhD  RRT 

Reviewing  the  Literature  and  Finding  a  Mentor 

Joseph  L  Rau  Jr  PhD  RRT 

A  Vignette:  The  p  value— Just  What  Is  It? 

Dean  R  Hess  PhD  RRT 

Validating  Patient-Driven  Protocols — Choosing  a  Design 

Charles  G  Durbin  Jr  MD 

A  Vignette:  Getting  Your  Abstract  Accepted 

Kaye  Weber  MS  RRT 

Plan  to  attend  on  Tuesday, 

December  5, 1995 

9:00-11:00  am 


Show 
Your  Pride 


T-shirt 

Show  pride  in  your  profession,  both 
coming  and  going,  with  this  new 
front-and-back  design.  This  50/50 
cotton/polyester  blend  T-shirt 
comes  in  a  fashionable  stonewashed- 
denim  color.  The  design  is  displayed 
in  navy  blue,  cream,  and  white.  Wear 
it  with  pride!  Medium,  large,  extra 
large,  and  extra-extra  large  available. 

Item  R16  $9.75 
($11.50  nonmembers) 

Add  $2.50  for  extra-extra  large. 

Sweatshirt 

This  luxurious,  heavyweight,  50/50 
blend  navy-blue  sweatshirt  sports  a 
plaid  applique  accented  with  gold 
embroidery.  Medium,  large,  extra 
large,  and  extra-extra  large  availabl 

Item  R19  $25  ($30  nonmembers) 

Add  $2.50  for  extra-extra  large. 

Cap 

Top  off  your 
ensemble  with  th 
embroidered  navy 
blue  cap.  One  size 
fits  all. 


•        ' 


Item  R17 

$6.50       4 

($9  nonmembers) 

To  order 

by  credit  card  or 

purchase  order,  call 

us  at 

(214)  243-2272. 

Shipping 

Rates* 

Order 

UPS 

UPS 

Next 

Total 

Regular 

2nd  Day 

Day 

$15  or  less 

$3.25 

$6.00 

$14.00 

$16  to  $30 

$3.75 

$8.00 

$18.00 

$31  to  $50 

$4.50 

$11.00 

$24.00 

$51  to  $75 

$5.50 

$13.00 

$31.00 

$76  to  $100 

$7.00 

$16.00 

$38.00 

$101  to  $125 

$8.00 

$19.00 

$50.00 

$126  to  $150 

$10.00 

$22.00 

$60.00 

$151  to  $200 

$12.00 

$27.00 

$75.00 

$201  or  more 

$15.00 

$32.00 

$90.00 

"Addresses  outside  the  conlincnl.il  United  Slates  require 

an 

additional  S 10  (or 

jrdcrs  up  to  S100;  add  SIS  for  orders 

over  SI00 

add  8.25%  sales  tax  (includin 
shipping  charges).  Texas  custoi 
that  are  exempt  from  sales  tax  mus 
attach  an  exemption  certificate. 


1 1030  Abies  Ln.,  Dallas,  TX  75229 


Youll  know  an  RT  when  you  see  one 


It  takes  a  certain  confidence  to  walk  up  to  a  complex, 
multi-million  dollar  radiation  therapy  unit  and  know 
exactly  how  to  deliver  the  prescribed  treatment. 

That  confidence  comes  only  from  being  well  educated 
in  the  nuances  of  three  critical  areas — technology,  anato- 
my and  human  nature.  Which  are  precisely  the  skills 
possessed  by  an  ARRT-registered  technologist. 

To  receive  certification  candidates  must  complete  years 
of  education,  then  pass  a  national  board  exam.  Ultimately, 
they  understand  better  than  anyone  how  to  use  sophisti- 
cated equipment,  as  well  as  how  to  soothe  bodies  and 
minds  in  pain. 


So  when  you're  looking  at  results  as  flawless  as  you  had 
envisioned,  you're  looking  at  the  work  of  a  well  educated 
registered  technologist. 

To  receive  details  regarding  certification  arid  advanced 
testing,  call  612-687-0048.  The  ARRT:  For  assured  quality 
of  care. 


J\UU    I  ""American  Registry 
r     ^I^SI^V  I  ^Radiologic  Technologists 

2  00,0  00    Registrants     Strong 


Circle  137  on  reader  service  card 


Authors  &  Advertisers 
in  This  Issue 


sc  in  RESPIRATORY  CARE,  contact  Advertising  Assistant  Bcih  Binkle)  at  (214) 

Fax  (214)  484-6010  for  rales,  media  kits,  and  recruitment  information.  Dale 
,  Respiratory  CARt-.'s  Marketing  Director. 


Blackson,  Tom 1 144 

Brooks  Jr.  C  Worth 1 120 

Ciarlo.  Joseph 1144 

Dennison.  Franklin  H 1 120 

Durbin  Jr.  Charles  G 1118 

Fluck  Jr.  Robert  R 1149 

Frye.  Thomas 1 120 

Haines.  Stephanie 1 149 

Hill.  Kim  Valeri 1 120 


Kollef,  Marin 1130 

Komara  Jr.  J  J 1 125 

Mishoe,  Shelley  C 1116.  1120 

Piedalue,  Fran 1 148 

Rizzo,  Albert 1 144 

Silver,  Patricia 1130 

Stoller,  James  K 1 125 

Watson,  Mary  E 1141 


Allen  &  Hanburys  Division  of  Glaxo  Wellcome  Inc.l  188-1 

Circle  Reader  Service  No.  109  See  ad 

American  Registry  of  Radiologic  Technologists 1 

Circle  Reader  Service  No.  137  Call  (612)  687-0048 

Arbor  Medical 1 

Circle  Reader  Service  No.  141  Call  (313)  663-6662 

Bird  Products  Corporation 1209,  1211-1213,  1 

Circle  Reader  Service  No.  1 10  &  127  Call  (800)  328-4139 

Criticare  Systems  Inc 1232-1 

Circle  Reader  Service  No.  126  Call  (800)  458-4615 

DeVilbiss  Health  Care  Inc 1 

Circle  Reader  Service  No.  162  Call  (814)  443-4881 

DHD  Diemolding  Healthcare  Division 1 

Circle  Reader  Service  No.  99  Call  (800)  847-8000 

Diametrics  Medical  Inc 1 

Circle  Reader  Service  No.  112  Call  (800)  949-4762 

Drager 1 

Circle  Reader  Service  No.  101  Call  (703)  817-0100 

Fisher  &  Paykel  Healthcare 1 

Circle  Reader  Service  No.  128  Call  (800)  321-3832 

Hamilton  Medical 1 

Circle  Reader  Service  No.  96  Call  (800)  HAM-MED- 1 

HealthScan  Products  Inc 11 14-1115,  1 

Circle  Reader  Service  No.  129  &  118  Call  (800)  962-1266 

HR  Incorporated 1 

Circle  Reader  Service  No.  139  Call  (800)  426-1042 

IMPACT  Instrumentation  Inc 1 

Circle  Reader  Service  No.  115  Call  (800)  969-0750 


191        Instrumentation  Laboratory 1 109 

Circle  Reader  Service  No.  124  Call  (800)  955-9525 

239        Laerdal  Medical  Corporation 1203 

Circle  Reader  Service  No.  140  Call  (800)  431-1055 

155        LIFECARE  International  Inc 1171 

Circle  Reader  Service  No.  159  Call  (800)  669-9234 

227        LuSal  Enterprises  Inc 1 187 

Circle  Reader  Service  No.  162  Call  (800)  426-7139 

233        Monaghan  Medical  Corporation 1166-1167.  1234-1235 

Circle  Reader  Service  No.  144  &  1 13  Call  (800)  833-9653 

208        Nellcor  Puritan  Bennett 1 105,  1217 

Circle  Reader  Service  No.  102  &  134  Call  (800)  NELLCOR 

098        Nellcor  Puritan  Bennett Cover  3 

Circle  Reader  Service  No.  155  Call  (800)  255-6773 

100        Newport  Medical  Instruments  Inc 1 1 1 1 

Circle  Reader  Service  No.  131  Call  (800)  451-31 1 1 

103        Passy-Muir  Inc Cover  2 

Circle  Reader  Service  No.  165  Call  (800)  634-5397 

231        Sherwood  Medical Cover  4 

Circle  Reader  Service  No.  104  Call  (800)  325-7472 

107        U.S.  Army 1159 

Circle  Reader  Service  No.  94  Call  (800)  USA-ARMY 

183        University  of  Louisville 1 159 

Circle  Reader  Service  No.  133  See  ad 

155        WB  Saunders  Company 1113 

Circle  Reader  Service  No.  132  Call  (800)  545-2522 

199 


Copyright  Information.  RESPIRATORY  CARI  is  copyrighted  by  Daedalus  Enterprises  Inc 
Reproduction  in  whole  or  in  part  without  the  express  written  permission  of  Daedalus  Enterprises 
Inc  is  prohibited.  Permission  to  photocopy  material  in  this  Journal  for  noncommercial  purposes  of 
scientific  or  educational  advancement  is  granted  Anyone  may.  without  permission,  quote  up  to  500 
words  of  material  in  this  journal  provided  the  quotation  is  for  noncommercial  use  and 
RESPIRATORY  CaRI  is  credited  Longer  quotation  requires  written  approval  by  the  author  and  pub- 
lisher. Single  reprints  arc  available  only  from  the  authors  Reprints  for  commercial  use  may  be  pur- 
chased from  Daedalus  Enterprises  Inc  For  information  and  prices  call  (214)  243-2272. 

IUsi  I  visll  R.  The  opinions  expressed  in  any  article  or  editorial  are  those  of  the  author  and  do  not 
necessarirj  refleel  the  views  ol  the  Editors,  the  American  Association  for  Respiratory  Care 
(AARC),  oi  Daedalus  Enterprises  Inc.  Neither  arc  the  Editors,  the  AARC  or  the  Publisher  respon- 
sible for  the  consequences  ut  the  clinical  applications  01  use  ot  any  methods  or  devices  described 
in  .in',  artit  le  oi  advertisement 

si  nsi  RIFTION  Kwrs.  Individual  subscription  rales  arc  $65  per  year  (12  issues).  $125  for  2 

years,  and  S IMS  for  3  years  in  Ihe  US  and  Puerto  Rico.  Rales  are  $80  per  year.  $155  for  2  years. 

i    )  seals  in  all  other  countries  (add  W  per  year  for  air  mail).  Single  copies  when 

hi. ii'i-     o II  ss    „i,t  s'  im  ail  i 1  postage  i<>  overseas  countries  (hecks  should  be  made 


payable  to  RESPIRATORY  Care  and  ■ 
TX  75229-4593. 


11030  Abies  Lane.  Dalla 


Subscription  Rates  eiir  associations.  An  association  may  offer  individual  subscriptions  of 
RESPIRATORY  Care  to  us  members  at  a  reduced  rate.  The  rates  based  on  membership  are:  $6  per 
year  for  101-500  members;  $5.50  for  501-1.500  members;  $5  for  1,501-10,000  members;  $4  for 
more  than  10,000  members  For  information,  contact  Ray  Maslerrcr  81(214)243-2272 

Change  ok  Address.  Notify  Respiratory  C  IRE  as  soon  as  possible  of  any  change  in  address 

Nole  the  subscription  number  (from  the  mailing  label!  and  your  name,  old  address,  and  new  adda-ss. 
Allow  6  weeks  lot  the  chance  To  avoid  charges  (or  replacement  copies  ol  missed  issues,  requests 
musl  he  made  within  60  days  in  Ihe  US  and  90  days  in  other  e 


MANUSCRIPTS.  The  Journal  publishes  clinical  studies,  mclhouVdcv  ice  evaluations,  reviews,  and 
oihei  materials  related  to  cardiopulmonary  medicine  ami  research,  Manuscripts  may  be  submitted 
to  ihe  Editorial  Office.  Respiratory  Care.  11030  Abies  Lane.  Dallas  TX  75229-4593 
Instructions  loi  authors  are  printed  in  every  issue  An  expanded  version  ol  ihe  instructions  is  .nail 
able  from  the  editorial  office, 

( ia>\He/M  0  1995,  by  Daedalm  Enterprtsa  In, 


1240 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


RESPIRATORy  CARE 


November  1995  Reader  Service  Reply  Card 


Expires  2/29/96 


Institution 
Street 


City/State/Zip 


For  faster  service,  FAX  to  (609)  786-4415 


Send  Free  Information 

on  the  Items  Circled  Below 

(Please  Circle  No  More  Than  15  Items) 

80 

81 

82 

83 

84 

85 

86 

87 

88 

89 

90 

91 

92 

93 

94 

95 

96 

97 

98 

99 

100 

101 

102 

103 

104 

105 

106 

107 

108 

109 

110 

111 

112 

113 

114 

115 

116 

117 

118 

119 

120 

121 

122 

123 

124 

125 

126 

127 

128 

129 

130 

131 

132 

133 

134 

135 

136 

137 

138 

139 

140 

141 

142 

143 

144 

145 

146 

147 

148 

149 

150 

151 

152 

153 

154 

155 

156 

157 

158 

159 

160 

161 

162 

163 

164 

165 

166 

167 

168 

169 

170 

171 

172 

173 

174 

175 

176 

177 

178 

179 

180 

181 

182 

183 

184 

185 

186 

187 

188 

189 

190 

191 

192 

193 

194 

195 

196 

197 

198 

199 

For  AARC  Membership  Information,  Circle  81. 

For  Respiratory  Care  Subscript 

on  Information,  Circle  82. 

RE/PIRATORy  C&RE 


November  1995  Reader  Service  Reply  Card 


Expires  2/29/96 


Institution 
Street 


City/State/Zip 


For  faster  service,  FAX  to  (609)  786-4415 


Send  Free  Information 

on  the  Items  Circled  Below 

(Please  Circle  No  More  Than  15  Items) 

80 

81 

82 

83 

84 

85 

86 

87 

88 

89 

90 

91 

92 

93 

94 

95 

96 

97 

98 

99 

100 

101 

102 

103 

104 

105 

106 

107 

108 

109 

110 

111 

112 

113 

114 

115 

116 

117 

118 

119 

120 

121 

122 

123 

124 

125 

126 

127 

128 

129 

130 

131 

132 

133 

134 

135 

136 

137 

138 

139 

140 

141 

142 

143 

144 

145 

146 

147 

148 

149 

150 

151 

152 

153 

154 

155 

156 

157 

158 

159 

160 

161 

162 

163 

164 

165 

166 

167 

168 

169 

170 

171 

172 

173 

174 

175 

176 

177 

178 

179 

180 

181 

182 

183 

184 

185 

186 

187 

188 

189 

190 

191 

192 

193 

194 

195 

196 

197 

198 

199 

For  AARC  Membership  Information,  Circle  81 . 

For  Respiratory  Care  Subscription  Information,  Circle  82. 

Ventilator,  they  comprise  a  ventilatory 
system  that  gives  you  more  than  respi- 
ratory and  metabolic  data.  It  gives  you 
the  means  to  look  beyond  the  surface 
to  evaluate  a  patient's  status  at  a  glance. 


I.    Type  of  Institution/Practice 

I .  □  Hosp  500  or  more  beds 

2  □  Hosp  300  to  499  beds 

3  D  Hosp  200  to  299  beds 

4.  LI  Hosp  100  to  199  beds 

5.  LI  Hosp  1 00  or  less  beds 

6.  □  Skilled  Nursing  Facility 

7.  □  Home  Care  Practice 

8.  □  School 

II.  Department 

A.  LI  Respiratory  Therapy 

B.  □  Cardiopulmonary 

C.  □  Anesthesia  Service 

D.  D  Emergency  Dept 

III.  Specialty 

1 .  O  Clinical  Practice 

2.  □  Perinatal  Pediatrics 

3.  Q  Critical  Care 

4.  J  Clinical  Research 

5.  L)  Pulmonary  Function  Lab 

6.  D  Home  Care/Rehab 

7.  LI  Education 

8    LI  Management 
IV.Position 

A.  a  Dept  Head 

B.  Q  Chief  Therapist 

C.  □  Supervisor 

D.  □  Staff  Technician 

E.  □  Staff  Therapist 

F.  U  Educator 

G.  LI  Medical  Director 
H.  LI  Anesthesiologist 
I     □  Pulmonologisl 
J.  □  Other  MD 

K.  □  Nurse 

V.  Are  you  a  member  of  the  AARC? 

1 .  LI  Yes      2.  H  No 


Type  of  Institution/Practice 

.  Q  Hosp  500  or  more  beds 

J  Hosp  300  to  499  beds 
.  U  Hosp  200  to  299  beds 
.  Q  Hosp  100  to  199  beds 
.  □  Hosp  100  or  less  beds 
.  □  Skilled  Nursing  Facility 

Q  Home  Care  Practice 

□  School 

.  Department 

.  U  Respiratory  Therapy 

.  LI  Cardiopulmonary 

.  LI  Anesthesia  Service 

.  LI  Emergency  Depl 

I.  Specialty 

.  D  Clinical  Practice 

D  Perinatal  Pediatrics 
.  D  Critical  Care 
.  D  Clinical  Research 

□  Pulmonary  Function  Lab 
Q  Home  Care/Rehab 

□  Education 

J  Management 
'.Position 
.  □  Dept  Head 
.  LI  Chief  Therapist 
.  LI  Supervisor 
.  □  Staff  Technician 
.  Q  Staff  Therapist 

□  Educator 

.  LI  Medical  Director 
.  LI  Anesthesiologist 
LI  Pulmonologist 

□  Other  MD 
.  LI  Nurse 

.  Are  you  a  member  of  the  AARC? 
LI  Yes      2.  Q  No 


ture.  So  you  won't 
l  energy  attempting  to 
mplete  daily  nutri- 
rom  inconclusive  spot 

its  more  clearly 

more  about  our  "New 
er  Insight,"  contact  the 
supplier  of  ventilator 
ellcor  Puritan  Bennett 


We  even  make  continuous  trending 
look  easy.  With  the  new  Graphics  2.0 
software  option,  you  can  opt  for  a 
breath-by-breath  display  of  metabolic 
parameters  like  Gs  consumption,  C02 
production,  respiratory  quotient  and 


With  the  new  7250  Metabolic  Monitor 
and  Graphics  2.0,  trending  parameters 
such  as  VO:  clearly  show  your  patient's 
response  to  decreased  ventilatory  support 
during  weaning. 


Ill   (U.S.A.) 

44-181-577-1870  (Europe) 

619-929-4551     (Far  East/ 

Latin  America) 


NELLCOR 
PURITAN 
BENNETT,, 


7200  and  7250  are  trademarks  of  Puritan-Bennett. 


Circle  155  on  reader  service  card 
Visit  AARC  Booths  802, 1302,  1303,  and  1305  in  Orlando 


Authors  <! 
in  This  Is 


Blackson.  Tom 

Brooks  Jr.  C  Wonh  .... 

Ciarlo.  Joseph 

Dennison,  Franklin  H . 
Durbin  Jr.  Charles  G  .. 

Fluck  Jr.  Robert  R 

Frye.  Thomas 

Haines,  Stephanie 

Hill.  Kim  Valeri 


NO  POSTAGE 
NECESSARY  IF 
MAILED  IN  THE 
UNITED  STATES 


BUSINESS  REPLY  MAIL 

FIRST-CLASS  MAIL     PERMIT  NO.  439    RIVERTON,  NJ 


POSTAGE  WILL  BE  PAID  BY  ADDRESSEE 


AARC  Publications 

PO  BOX  11605 

RIVERTON    NJ   08076-7205 


Allen  &  Hanburys  Div 
Circle  Reader  Service  Ni 

American  Registry  of  l 
Circle  Reader  Service  Ni 

Arbor  Medical 

Circle  Reader  Service  Nc 
Bird  Products  Corpora 

Circle  Reader  Sen  ice  Nc 

Criticare  Systems  Inc . 
Circle  Reader  Service  N< 

DeVilbiss  Health  Care 

Circle  Reader  Service  Nc 

DHD  Diemolding  Hea 

Circle  Reader  Service  Nc 

Diametrics  Medical  Inc 

Circle  Reader  Service  Nc 

Driiger 

Circle  Reader  Service  N( 

Fisher  &  Paykel  Healtl 

Circle  Reader  Service  Nc 

Hamilton  Medical 

Circle  Reader  Service  N< 

HealthScan  Products  Ii 

Circle  Reader  Service  Nc 

HR  Incorporated 

Circle  Reader  Service  Nt 

IMPACT  Instrumental 

Circle  Reader  Service  Nc 


III...I..I.II...I...I.II..I...I..I.III....I.I..I.I.I 


NO  POSTAGE 
NECESSARY  IF 
MAILED  IN  THE 
UNITED  STATES 


BUSINESS  REPLY  MAIL 

FIRST-CLASS  MAIL     PERMIT  NO  439    RIVERTON,  NJ 


POSTAGE  WILL  BE  PAID  BY  ADDRESSEE 


AARC  Publications 

PO  BOX  11605 

RIVERTON    NJ   08076-7205 


Copyright  information,  re 

Reproduction  in  whole  or  in  part  muiuw  ok  tAptcoa  wuucii  [fuuiuaiuu  ui  watumuj  Daminisca 
Inc  is  prohibited  Permission  to  photocopy  material  in  this  Journal  for  noncommercial  purposes  of 
scientific  or  educational  advancement  is  granted.  Anyone  may.  without  permission,  quote  up  to  500 
words  of  material  in  this  journal  provided  the  quotation  is  for  noncommercial  use  and 
RESPIRATORY  CARE  is  credited  Longer  quotation  requires  written  approval  by  the  author  and  pub- 
lisher. Single  reprints  are  available  Only  from  the  authors  Reprints  for  commercial  use  maybe  pur- 
chased from  DaedaltU  Enterprises  Inc  For  information  and  prices  call  (214)  243-2272 

DlSt  I  MM!  K.  [Tie  opinions  expressed  in  any  article  or  editorial  are  those  of  the  author  and  do  not 
necessaril)  reflect  the  views  of  the  Editors,  the  American  Association  for  Respiratory  Care 
(AARC).  or  Daedalus  Enterprises  Inc.  Neither  arc  the  Editors,  the  AARC  or  the  Publisher  respon 

sibic  for  the  consequences  ui  the  clinical  applications  or  use  of  any  methods  oi  devices  described 
iii  .in .  artii  le  oi  advertisement, 

Sl  list  HUM  ion  RATES.  Individual  subscription  rates  arc  $65  per  year  (12  issues).  $125  for  2 
years,  and  $185  lor  3  \cars  in  the  US  and  Puerto  Rico,  Rates  are  $80  per  year.  $155  for  2  years, 
and  $230  for  3  years  m  .ill  olhei  •  ountries  (add  $84  pei  yeai  foi  ail  mail),  Single  copies  when 
available  cost  S5;  add  $7  for  air  mail  postage  to  overseas  countries  Checks  should  be  made 


l...l..l.ll...l...l.ll..l.„l,.l,lll„„l.l,,l,l,l 


SUBSCRIPTION  Rates  FDR  ASSOCIATIONS.  An  association  ma>  offer  individual  subscriptions  of 
Respiratory  Care  to  its  members  at  a  reduced  rate.  The  rates  based  on  membership  are:  $6  per 
year  for  101-500  members;  $5.50  for  501-1.500  members;  $5  for  1,501-10.000  members;  $4  for 
more  than  10,000  members.  For  information,  contact  Ray  Masferrer  at  (214)  243-2272, 

CHANGE  OF  ADDRESS.  Notify  Respiratory  CARE  as  soon  as  possible  of  any  change  in  address 
Note  the  subscription  number  (from  the  mailing  label)  and  your  name,  old  address,  and  new  address, 
Allow  6  weeks  lor  the  change  To  avoid  charges  lor  replacement  copies  of  missed  issues,  requests 
must  be  made  within  61)  days  in  the  US  and  90  days  in  other  c 


Mam  scrums.  I  he  Journal  publishes  Jimcal  studies,  method/device  evaluations,  reviews,  and 
other  materials  related  to  cardiopulmonary  medicine  and  research.  Manuscripts  may  be  submitted 
to  the  Editorial  Office.  RESPIRATORY  CARE,  11030  Abies  Lane.  Dallas  TX  75229-4543, 
Instructions  for  authors  are  printed  in  ever)  issue  An  expanded  version  ol  the  Instructions  is  avail- 
able from  the  editorial  office. 

CopyrtgktQ  iws,  by  Daedalus  Enterprises  in, 


1240 


Respiratory  Care  •  November  '95  Vol  40  No  1 1 


The  act  of 


I  n  s 


apprehending 


the  inner  nature 


of  things 

or  of 

seeing  intuitively. 


L 


ook  closely. 


Here  lies  the  reflection  of  your  good 
judgement.  In  recognizing  that  your 
patients  rely  upon  the  most  qualified 
clinical  decisions,  Nellcor  Puritan 
Bennett  brings  you  effective  informa- 
tion tools  for  making  them  with  confi- 
dence and  clarity. 

Introducing  new  trending  parameters 
for  the  7250  Metabolic  Monitor 

Together,  with  the  7200"  Series 
Ventilator,  they  comprise  a  ventilatory 
system  that  gives  you  more  than  respi- 
ratory and  metabolic  data.  It  gives  you 
the  means  to  look  beyond  the  surface 
to  evaluate  a  patient's  status  at  a  glance. 


'"«..„    „>    ,»'«    ,*'„,    „'„  _  „',. .  ■  ,J.r  ell. 

»,M 1                                                     -      88 

According  to  Dr.  C  Price,  M.D.,  CM., 

F.R.C.P.  and  Gail  Lang,  RRT,  of  Credit 

Valley  Hospital  in  Ontario  Canada, 

"In  our  opinion,  the  7250 
Metabolic  Monitor  provided  an 

accurate  assessment  of  our 
patient's  nutritional  requirements 

and  assisted  us  in  making  the 

necessary  adjustments  to  quickly 

wean  him  from  the  ventilator." 

We  even  make  continuous  trending 
look  easy.  With  the  new  Graphics  2.0 
software  option,  you  can  opt  for  a 
breath-by-breath  display  of  metabolic 
parameters  like  02  consumption,  C02 
production,  respiratory  quotient  and 


With  the  new  7250  Metabolic  Monitor 
and  Graphics  2.0,  trending  parameters 
such  as  VO:  clearly  show  your  patient's 
response  to  decreased  ventilatory  support 
during  weaning. 


energy  expenditure.  So  you  won't 
waste  your  own  energy  attempting  to 
estimate  the  complete  daily  nutri- 
tional picture  from  inconclusive  spot 
checks. 

See  your  patients  more  clearly 

To  find  out  more  about  our  "New 

Tools  for  Greater  Insight,"  contact  the 

world's  leading  supplier  of  ventilator 

systems.  Call  Nellcor  Puritan  Bennett 

at     800-255-6773  (U.S.A.) 

44-181-577-1870  (Europe) 

619-929-4551     (Far  East/ 

Latin  America) 


NELLCOR 
PURITAN 
BENNETT, 


trademarks  of  Puritan-Bennett, 
n  Bennett.  All  rights  reserved. 


Circle  155  on  reader  service  card 
Visit  AARC  Booths  802,  1302,  1303,  and  1305  in  Orlando 


B1995  Nellcor  Porta 
A-AA2210-00  (9/95) 


INTRODUCING 
3  NEW  Technologies  in  Arterial  Blood  Sampling 


ASPIR-    PULSE 


Arterial  Blood  Gas  System 


NEW,  Advanced  JKSPIR-PULSE™  Syringe 


Patented  design  improves  filling  for  both 
Aspiration  and  Pulsation  techniques 


NEW,  Purge  Guard ™ 

One-Handed  Safety  Needle  Venting  System 


Patent-pending  design  allows  One-Handed  operation 
to  immediately  Purge  Air  Bubbles,  immediately  ' 
Guard  the  needle  point  and  immediately  free  the 
other  hand  to  apply  pressure  at  the  puncture  site 


NEW,  Total  Ca++  Lyte ™ 

Precision  Heparin 

A  breakthrough  patented  heparin  to  maximize  the 
precision  of  test  results  obtained  from  the  new  critical- 
care  blood  gas  and  critical  analyte  analyzers 


7^\*  7 

/k^?*  , 

;-ir^A 

<JT"> 

0           y1^-. 

^*^7\ 

'*    /^-\ 

► 


I 


> 


See  your  Sherwood  Medical  OR  /Critical  Care  Sales  Representative  or  call  1-800-325-7472  for  a  complete  listing  of 

ASPlR-Pu/se    Arterial  Blood  Gas  Kits. 


0 1 994  Sherwood  Medical  Company 


A  Sherwood 
MEDICfll 


Circle  104  on  reader  service  card 
Visit  AARC  Booths  533  and  535  in  Orlando