CASE I.
Wherein the action of the heart fails before that of the respiratory organs.
In no case of this description can artificial inflation of the lungs afford the least assistance, for the left side of the heart always contains florid blood at the moment of its cessation; and since this fact proves that it failed in its action, while under the full influence of duly oxygenized blood, how can we expect that the stimulus, which was unable to preserve the heart’s action while yet in motion, shall be able to re-excite it after it has ceased? Such a practice can only have been suggested by that erroneous physiology which maintained that the motion of the lungs excited that of the blood.
The preservation of the body from the influence of external cold is always important, for it is only within a certain range of temperature that the vital functions can be performed; and during a state of asphyxia, the body is necessarily incapable of generating any portion of animal heat; where the heat is lost it should be gradually restored, and for such a purpose the introduction of wine, the volatile alkali, and other stimulants, into the stomach, by means of a flexible tube, would probably, in certain states of syncope, prove serviceable; although in cases of suffocation it can never occasion the least benefit. We have been also directed to employ frictions on the surface of the body, for the purpose of assisting the circulation of the blood; as if, says Mr. Brodie, (Manuscript Notes) this could answer any useful purpose where the action of the heart has ceased, or as if it could be necessary where it still continues.
Under the head ‘death from cold,’ we have stated that the left cavities of the heart contain florid blood; it therefore follows that the directions of the Humane Society, to inflate the lungs in such cases, are founded in error.
CASE II.
Wherein the function of respiration ceases, while the heart continues to circulate black blood.
It has been stated that in cases of suffocation the heart continues to contract for a short period, after the cessation of breathing; that this interval is extremely short, but liable to vary from several causes; and that it is uniformly shorter in cases of death by drowning, than in those by strangulation. To the physician this is an interval of anxiety and importance; let him beware how he trifles with the fleeting moments, in which alone the resources of his art can be of any avail. If artificial respiration be established at this period, the blood will become once more oxygenised, the action of the heart will be continued, the scarlet blood will be transmitted to the brain, and sensibility will therefore return; the nervous energy will be once more transmitted to the respiratory organs, and the animal will at length make a voluntary effort to inspire air. Here then is the interval of time, during which artificial breathing may be employed so as to effect a restoration to life, where death must otherwise have been inevitable. Mr. Brodie has made a great variety of interesting experiments upon this subject, from which may be deduced the following important corollaries.
1. If the lungs be inflated, the action of the heart will continue.
2. If the action of the heart has become feeble, but the circulation is nevertheless not entirely suspended, the inflation of the lungs will cause the feeble actions to become again frequent and vigorous.
3. If the action of the heart has entirely ceased, it is impossible to restore it by the inflation of the lungs.
4. If the action of the heart has not entirely ceased, but is so feeble as no longer to maintain the circulation, the artificial respiration will prove as useless, as if the heart were perfectly motionless.