Skip to main content

Full text of "Medical Jurisprudence And Toxicology"

See other formats

POTASSIUM                                                        561

Post-mortem Appearances.—The mucous membrane of the stomach is stained bright
red or brownish-red, inflamed and detached in various parts. The small intestine is
acutely inflamed. The blood is liquid.

Medico-Legal Points.—Accidental poisoning by potassium nitrate, though rare, has
sometimes occurred from its use in mistake for sugar, magnesium sulphate or sodium
sulphate. In his annual report for the year 1939, the Chemical Examiner, Bengal, des-
cribes a case, in which a female child, about 10 months old, was given one morning by
her mother a feed of milk mixed with some potassium nitrate which was mistaken for
sugar. The child died in the afternoon. In the annual report of the Chemical Examiner
of the United and Central Provinces for the year 1921, a case is recorded where potas-
sium nitrate was given as a purgative by mistake for magnesium sulphate with a fatal

Potassium nitrate has been used for suicidal purpose and also for the purpose of
procuring criminal abortion.   Used as an enema containing 124 grains, it has caused death.
Potassium nitrate is eliminated largely in the urine and to a slight extent in the
saliva and sweat.   A small portion may be reduced to nitrite.

Potassium Chlorate, KC1O3.—This is a colourless, crystalline salt with a cool, saline
taste, soluble in 16 part's of cold water and in 3 parts of boiling water, but almost insoluble
in alcohol. Potassium chlorate is a pharmacopceial preparation, the dose being 5 to
10 grains.

Symptoms.—When swallowed in large doses, it causes pain in the stomach and
abdomen, severe vomiting, diarrhoea, giddiness, headache and muscular weakness. When
absorbed, it breaks up the red blood corpuscles, converting haemoglobin into methaemo-
globin and setting up secondary symptoms, such as pain in the loins, hsemoglobinuria,
partial suppression of urine, the urine being dark in colour and containing albumin and
bloody tube-casts, cyanosis of the skin, jaundice, drowsiness, delirium, coma and death.
Fatal Dose.—According to Witthaus,65 the smallest fatal dose is 3 drachms for an
adult, 75 grains for a child and 15 grains for an infant. It must be remembered that a
quantity taken in divided doses is more apt to cause death than when taken in a single

Fatal Period.—The shortest recorded fatal period is 2J hours in the case of a child,
three weeks old, and the longest period for an adult is 12 days.60

Treatment.—Administer emetics, or wash out the stomach, and give alkaline drinks to
increase the flow of urine and pilocarpine hypodermically to stimulate its excretion by
the saliva. Use oxygen inhalation, stimulants, transfusion of denbrinated blood, or normal
saline solution.

Post-mortem Appearances.-~Submucous haemorrhages in the mucous membrane of
the stomach and duodenum, which is swollen, reddened and easily detached, The liver
and spleen are enlarged and dark-brown in colour. The kidneys are enlarged and
inflamed. The lungs are marked with subpleural ecchymoses. The heart is dilated.
The brain and its membranes are congested. The blood is chocolate coloured with
degenerated red blood corpuscles.

Chemical Tests.—Acidify the suspected solution with dilute sulphuric acid and add
a few drops of indigo solution until the colour is blue. The addition of sulphurous acid
will discharge the blue colour, if potassium chlorate be present.

A few drops of potassium iodide solution and a drop of starch solution are added
to a solution of potassium chlorate. On the addition of acetic acid an intense blue colour
is produced.

A few drops of platinic chloride solution added to an acidified solution of potas-
sium chlorate produces a yellow crystalline precipitate, insoluble in alcohol (80 per cent).

Medico-Legal Points.—Potassium chlorate is largely used in the manufacture of
matches and in pyrotechny, and in calico-printing and dyeing. It must be handled care-
fully, as it explodes when rubbed with many substances, especially sulphur, sulphides,
sugar, charcoal, tannic acid and glycerin.

Accidental cases of poisoning occur chiefly from an overdose of potassium chlorate
or from it having been swallowed hi mistake when prescribed as a gargle. A man, aged
43 years, who was suffering from Bright's disease, took 30 to 35 grammes of potassium
chlorate over a period of three days in mistake for potassium chloride and died on the
fifth day after the last dose.67 A woman,68 61 years old, sucked twenty 5-grain tablets
of potassium chlorate daily for six to ten weeks with the idea of curing a supposititious
cancer of the tongue, and died after suffering from gastro-intestinal disturbances, severe

65.   Manual of Toxic., Ed. II, p. 691.

66.   Witthaus, Manual of Toxic., Ed. II, pp. 692, 693.

67.    Cochrane, W. J., and Smith, R. P,, Canad. Med. Assoc. Jour., Jan. 1940, XLH, p. 23.

68.   S. Gordon and J. A. H. Brown, Lancet, Oct. 4, 1947, 2, p. 503,