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after death to a sufficient extent to interfere with the liquid properties of the fluid. In no case
was any effect upon the respiration produced by change of position in the animal. In a number
of cases, however, when the feet were elevated, the heart, which had entirely ceased beating,
recommenced its work, and I have several times seen a pulse entirely disappear when the
animal was taken from the vertical to the horizontal position. On the other hand, very
frequently it was impossible to affect the cardiac action by changing the position of the animal.
Nevertheless, the phenomena spoken of occurred too frequently to be a mere outcome of chance,
though I several times noted that the heart was usually more affected by alternately elevating and
depressing the feet of the animal than by keeping it in a steadily elevated or horizontal position.
When the circulation has practically ceased, under the depressing influence of an
anæsthetic, inverting the body must cause the blood which has naturally collected on the enor--
mously relaxed vessels of the abdomen, to flow into the right side of the heart and distend it,
and this distension—this increase of pressure—appears at times to have a sufficient momentary
influence to stimulate the failing organ.
The theory which has been advocated by some therapeutics—that inversion of the body
is of value in the accidents of anæsthesia, because it causes the vital centres of the brain to be
supplied with blood—is probably incorrect. The respiration in anæsthesia fails, not through
want of blood in the respiratory centres, but because the blood contains a poison which paralyses
these centres.
The most remarkable results which I have reached in bringing about recovery of
animals to all ordinary intents and purposes dead, were obtained through the use of artificial
respiration. Thus, I have seen an animal, in which no respiratory movements whatever had
taken place for two minutes, and in which, during that time, no movements of blood had
occurred in the carotid artery, and in which, therefore, the heart had ceased its beat, rapidly
permanently restored by artificial respiration.
At one time in these researches, it appeared as though after any dose of chloroform by
inhalation, the animal could be resuscitated by artificial respiration, even though heart and
lungs were completely paralysed by the drug; but finally I did find a case in which artificial
respiration failed.
The results of my experiments with the lower animals may be summed up: that nitrite
of amyl, caffeine, and atropine are of little or no use in chloroform poisoning; that alcohol,
when given in small amounts, has no influence, but that when given largely, materially assists
in paralysing the heart and producing fatal results; that ammonia has some little influence upon
the heart, but that of all substances tried, digitalis was by far the most powerful in stimulating
the failing circulation; indeed, my experimental results indicate that it is the only known drug
which is of any real practical value in such cases. Next, or perhaps even before digitalis,
strychnine seems to be of value in the accidents of anæsthesia, because, whilst having some
influence on the circulation, it affects powerfully the respiration. For many years chlorofrom
has been used in practical medicine as the physiological and practical antagonist to strychnine,
and it seems rather odd that strychnine should never have been employed as the practical
antagonist to chloroform.