DIAGNOSIS OF POISONING--DUTIES OF THE PRACTITIONER.
The chief characteristics of poisoning mentioned by authors of repute
are, that the symptoms commence suddenly after taking any substance or
fluid into the stomach, the individual being in a state of health; that
they increase steadily, and are uniform in their nature throughout their
course; and that they prove rapidly fatal. There are many exceptions to
these rules. Thus if the stomach be loaded the appearance of the
symptoms will often be delayed some few hours. Sleep, according to Dr.
Christison, may retard the action of some agents; so that if a person
fall asleep soon after swallowing arsenic or strychnia, for example, no
effect may ensue for four or five hours. Intoxication will mask the
effect of narcotics. Again, the individual poisoned may possibly be
suffering from disease, and an agent may be given which will only
aggravate existing symptoms. The fact must not be forgotten that
sometimes a poisonous draught is substituted for a harmless medicine.
And lastly, after a poison has manifested its effects the symptoms often
remit for a time.
When poison is administered with a criminal intent it is generally in
such a dose as to take immediate effect, although this is by no means
necessary, as there are numerous substances which accumulate in the
system, and when given in small and repeated quantities, ultimately
prove fatal. It must also be remembered that there are many diseases, as
malignant cholera, internal hemorrhage, &c., which commence suddenly,
and rapidly run to a fatal termination. In inflammation of the stomach
or intestines the symptoms often set in suddenly, and might be mistaken
for poisoning; such is also the case in intestinal obstruction, and
especially in ulceration and perforation of the bowels. So also in
organic diseases of the heart, where the symptoms may have remained
latent for some time, death often occurs suddenly from syncope. The
diagnosis of the effects of irritant poisons is not so difficult as it
is in the case of narcotics or other neurotics, where the symptoms are
very similar to those produced by apoplexy, epilepsy, tetanus,
convulsions, or disease of the brain.
Generally speaking, a person may be supposed to be suffering under the
effects of a poison, if soon after taking food or drink, he be seized
with violent pain, vomiting, disorder of the alimentary canal, and
convulsive movements: or if he be attacked under the same circumstances
with vertigo, delirium, or great drowsiness. It must not be forgotten,
however, that poisons may be introduced into the body, not only by the
mouth, but also by means of suppositories and enemata, or in females by
vaginal injections, or by inhalation, or by subcutaneous injection, or
through the true skin after the removal of the cuticle. Should death
ensue, the presumption of unfair play will of course be strengthened by
the discovery of post-mortem appearances similar to those known to be
produced by the poison from which the person apparently suffered.
The post-mortem appearances, however, except in a few instances, are not
very characteristic; nevertheless they may be of great _negative_ value
in proving that a certain poison has not been administered, or that the
patient died from the effects of disease. Two symptoms, excessive
lividity of the body and early putrefaction, formerly supposed to
indicate death by poison, are now known to frequently follow other modes
of death. It may nevertheless be remarked, that the appearances after
death which may be produced by poisons are, in one great class, the
signs of inflammation of the alimentary canal; in another, the signs of
congestion of the nervous system; and in a third, a combination of the
two.
The detection of poison in some of the food which has been left untaken
or in the matters vomited would seem to be conclusive evidence of the
administration of poison; but it is to be recollected that designing
persons have mixed noxious materials with food or rejected matters, in
order to feign poisoning, or to cast unjust imputations upon others.
When called to a case of supposed poisoning during life the
practitioner's duty is two-fold. His first aim must of course be to
preserve life (see next chapter); his second, to forward the interests
of justice. But if he reaches the spot too late to save life his duties
are undivided, for he has but to see that justice is done, and in order
that there be no failure it is important that all his observations be
committed as speedily as possible to writing. He should inquire the time
at which any substance was last taken, the nature of the symptoms, the
hour at which they commenced, and the precise time at which death
occurred. He must take possession of any food, medicine, vomited
matters, urine, or faeces which may be in the room; and if possible he is
to seal them up, in new and clean vessels, duly labelled, for
examination. Then the position and temperature of the body are to be
observed, the appearance of the countenance, the presence or absence of
rigor mortis, with the nature and warmth of the apartment, the situation
of any marks of violence, and the condition of the inside of the mouth
and gullet. In addition to the ordinary rules to be observed in
conducting post-mortem examinations in cases of suspected poisoning,
something more must be done with a view to preserving portions of the
body for subsequent examination. The alimentary canal is the most
important organ to be thus secured, and it should be removed in separate
portions. A double ligature should be passed round the oesophagus in
the chest, and the duodenum a few inches below the pylorus should be
secured in like manner; by cutting across the gullet and gut between
these ligatures, the stomach may be removed without any danger of
spilling its contents. It is best to open the stomach after it has been
introduced into the receptacle prepared for it, so that its pathological
condition may be noted as early as possible. Another ligature should be
tied low down in the rectum, and the intestines removed and introduced
into a separate vessel prepared for them and then examined like the
stomach. Sometimes it may be necessary to remove the gullet in like
fashion. As much blood as possible should be saved for the chemist, and
a portion of the liver, if not the whole organ, should also be secured.
When everything has been tied up, the jars should be sealed, numbered,
labelled, and initialled, to prevent subsequent confusion and to
facilitate identification. In women the vagina, uterus and ovaries must
be inspected, the brain, spinal cord and thoracic viscera ought likewise
to be examined, and portions of the spleen, kidneys, and muscles should
be reserved for analysis. No antiseptic or preservative fluid is to be
used. When possible it will be best to make the autopsy within
twenty-four hours after death; taking care to make the examination
patiently, thoroughly, and with a mind free from any bias. Poison may be
found in a body, and yet a question may arise as to its having been the
cause of death. Hence in these investigations every organ of the body is
to be examined, in order to learn whether any disease has existed
sufficient to account for the fatal result.
Any suspicious conduct on the part of those surrounding the poisoned
individual should be carefully noted. Acts of this kind arrange
themselves in three heads, as occurring before, or during the fatal
illness, or after death. With the first category the practitioner has
ordinarily nothing to do, but his attention to those coming under the
second and third is often of essential service to the ends of justice.
The kind of acts will suggest themselves to every one, and need not be
further referred to here.