In farther illustration of these views, let us observe the mode in which death takes place in apoplexy, or in cases of pressure on the brain, whether occasioned by a depressed portion of bone, or by blood extravasated within the cranium. At first the patient is insensible to all external impressions, but the breathing is not affected; after an interval, however, the respiration becomes difficult and laborious, and the purple hue of the lips and cheeks, from the sub-cutaneous vessels, demonstrates that the blood is imperfectly oxygenized. The arterial action becomes more slow, in proportion only as the respiration is more difficult; and the pulse may even be distinguished at the wrist, after the breathing has altogether ceased; under such circumstances it is obvious that life might be protracted for several hours by artificial inflation of the lungs, but as no ultimate benefit could be derived from such an operation, its expediency may be fairly questioned.
Enough has been said to shew that the brain is not immediately necessary to the action of the heart; but Mr. Brodie has very justly observed that the general proposition thus established, must not lead us to the conclusion that the heart is therefore incapable of being affected by violent impressions on the nervous system; the fact is quite otherwise, for although the brain may be removed, and the circulation be nevertheless maintained by artificial respiration, yet an injury inflicted on the brain, of another kind, may be followed by those immediately fatal consequences which decapitation itself would not produce. Dr. Wilson Philip states that if the brain be violently crushed, the action of the heart is immediately stopped; and the fact is too notorious to be questioned, that a blow on the head is frequently succeeded by Syncope; there are but few circumstances, says Mr. Brodie, in the history of the animal œconomy which appears more remarkable than this fact, that an injury of a part which is not immediately essential to the heart’s action, should nevertheless, under certain circumstances, have the effect of occasioning its immediate cessation. The late researches of Le Gallois may perhaps receive farther elucidation from the above proposition; this physiologist has stated that if a wire be introduced into the Theca vertebralis, and be moved upward and downward, so as to destroy the texture of the spinal marrow, the action of the heart presently ceases; and he from thence advances to the conclusion, not only that the spinal marrow is necessary to the heart’s action, but that every part of the animal body derives its vital properties from it; from what I have observed, says Mr. Brodie (Manuscript Notes) in the repetition of the foregoing experiment, I should infer that the fact is correctly stated, as far as it relates to warm-blooded animals, but the conclusions are undoubtedly premature; and the history of the fœtus, as related by Lallemand, in which, notwithstanding the absence of the brain and spinal marrow, the child was even larger than usual, the heart perfect, and it was manifest that the circution had been duly performed, is in direct opposition to such a theory. We must here agree with Mr. Brodie, that such phenomena are quite incompatible with the doctrine in which the spinal marrow is supposed to be directly necessary to the existence of vitality in the system generally, and to the action of the heart in particular; and that we must therefore look for some other explanation of the effects which are produced by the destruction of the spinal marrow in warm-blooded quadrupeds.—May they not be explained by supposing them to be the effect of the shock which must necessarily attend the removal of the spinal marrow, which can never be effected with the facility that attends decapitation?
We have deemed it necessary to offer these few remarks upon the relations which subsist between the functions of the heart, lungs, and brain, in as much as the propositions which have been thus established respecting them, can alone lead to a correct pathology of those diseases, by which life is suddenly extinguished, or suggest a rational and effectual plan of treatment, in cases of suspended animation.
SYNCOPE:
In which the pulsations of the heart cease, before the action of the respiratory organs.
The heart may cease to beat either from organic lesions in its own structure, or in that of its vessels; or from being sympathetically affected by injuries in other parts[[20]]; or from the operation of certain poisons; or from a shock of the general nervous system, as experienced in paroxysms of certain passions.
In ordinary fainting it is evident that some slight and feeble motions of the heart still continue, although insufficient to produce a sensible pulsation in the more distant arteries; and where this has continued for an unusual period, and the respiration has been so obscure as to escape common observation, the phenomenon has been eagerly seized by the admirers of the marvellous, and credulity has attached to its history, under the name of Trance,[[21]] circumstances of extravagance and mystery, to which it can hardly be necessary to allude on the present occasion. But the motions of the heart may have ceased altogether, and in such cases it becomes a question, no less interesting to the practical physician than to the physiologist, whether they can ever be restored, and if so, we have to inquire under what limitation, as to time; under what circumstances; and by what means? The views which have been already offered respecting the pathology of Syncope will afford us considerable assistance in the solution of a problem, so intimately connected with inquiries of forensic importance. It would appear that where the heart has ceased to pulsate, in consequence of the cessation of respiration, it can never again be set in motion; but that where it has stopped from other causes, as from the operation of certain poisons, its muscular irritability not having been exhausted, its action may be occasionally revived. Where Syncope arises from hemorrhage, we shall find, on dissection, that the heart and its great vessels are either empty, or contain only a small quantity of blood in their cavities; but where Syncope arises from other causes, the heart is seen distended to an unusual magnitude, and the blood in the left auricle and ventricle is generally of a more or less florid colour, and has not the hue of venous blood; a circumstance which depends upon the pulsation of the heart ceasing before the function of respiration, and which is the very reverse of what happens in death from suffocation, as we shall hereafter explain.
Violent passions of the mind very commonly produce syncope, which has in some instances terminated in death; we are however inclined to believe that in fatal cases of this nature the persons must have laboured under some organic affection of the heart, or its vessels; Philip V. died suddenly on being told that the Spaniards had been defeated, and on opening the body, his heart was found ruptured.
Dr. Tissot relates also the case of the father of a numerous family, who having lost his wife whom he tenderly loved, was suddenly seized with laborious respiration, and died at the end of two days; when the lungs were found gorged with blood, and the heart ruptured. Now in both these cases, it is probable that the muscular structure of the heart had been softened by previous disease.[[22]] So in the case of Mr. John Hunter, whose life was suddenly extinguished by mental emotion, the valves of the heart had been long in a state of disease, and so well aware was he of the danger to which he was constantly exposed, that he had for some time previous to his death, been in the habit of retiring from all those situations, in which his passions were likely to be excited. It is said that the instances of death from sudden joy are more numerous than those from grief, probably because the effect of this latter passion is rather to retard than to accelerate the circulation; Sophocles, being desirous of proving that at an advanced age he was in full possession of his intellectual powers, composed a tragedy, was crowned, and died through joy; the same fate befel Philippides the comic writer; thus too the Lacedemonian Chilon expired in the embrace of his son who had borne away the prize at the Olympic games; and we read of Roman women who died in the same manner, upon seeing their sons return from the battles of Thrasymene and Cannæ. On the other hand, we might adduce much classical authority to shew that death has frequently been the sudden effect of grief.
Montaigne relates the case of a German, who after having performed great feats of valour, was killed at the siege of Osen; one of the general officers having desired to see the corpse of so gallant a man, was conducted to the body, when he instantly recognised the features of his own son, and died on the spot. The record of our own times will furnish us with an instance in which an actor of celebrity suddenly expired upon repeating a passage that contained a fancied allusion to the domestic affliction under which he was suffering.
Dr. Ozanam,[[23]] in illustration of the influence of pain and terror in producing sudden extinction of life, relates the case of a middle aged criminal, who having throughout evinced extreme weakness and depression, expired in his way to the scaffold, and was stiff before he arrived at the place of execution, which was about seven miles distant.