Lectures on the principles and practice of physic : delivered at King's College, London / by Thomas Watson.

  • Watson, Thomas, Sir, 1792-1882.
Date:
1844
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Licence: Public Domain Mark

Credit: Lectures on the principles and practice of physic : delivered at King's College, London / by Thomas Watson. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    ment may be traced of this or that vital function; and a tendency is more or less clearly manifest to one or the other of the modes of dying, which we may now proceed to con- sider in succession. Death by anaemia.—And first let us examine that form of death which is caused by a want of the due supply of blood to the heart. This is called, with much propriety, death by anaemia. The best examples of death taking place in this way are those in which it is the conse- quence of sudden and profuse hemorrhage. The circulation fails, not because the heart has lost its power of contraction, but because blood does not arrive in its chambers in BufBcient quantity. We assure ourselves of this in two ways. In the first place, when the body of an animal is examined immediately after death from sudden and copious loss of blood, the heart is not found dilated, and full of blood, as it would be if it had ceased to act from a want of power to contract upon its contents; but it is found empty, or nearly so, and contracted. Secondly, this conclusion is confirmed by the reverse experiment: by the effect, I mean, of Ihe transfusion of blood. It is a fact well ascertained, first by experiments made upon animals, and afterwards by most happy trials upon the human subject, that in cases of apparent death from violent hemorrhage the suspended functions may be restored by con- veying a timely supply of blood into the vessels of the seemingly dead animal from the veins of a living animal of the same species. Now it is quite clear that this introduction of fiesh blood could be of no avail in a case where the heart was unable to act upon the blood which had reached it. The phenomena which attend this mode of dying are paleness of the countenance and lips, cold sweats, dimness of vision, dilated pupils, vertigo, a slow and weak pulse, and speedy insensibility. With these symptoms are frequently conjoined nausea, and even vomiting, restlessness and tossing of the limbs, transient delirium: the breathing is irregu- lar, sighing, and, at last, gasping; and convulsions generally occur, and are once or twice repeated, before the scene closes. It is thus that women often die, in whom flooding happens after childbirth. Some- times the sudden bursting of an aneurism occasions this form of death. It is common on the field of battle, and in accidental injuries whereby large blood-vessels are wounded. Internal hemorrhage, depending upon diseases to be hereafter described, may also prove fatal in the same manner. Death by asthenia.—This, then, is one form of death beginning at the heart. Another form, the converse of this, but spoken of also as death beginning at the heart, is that in which there is no deficiency of the proper stimulus to the heart's action, but a total failure of contractile power in that organ. This is well denominated death by asthenia. Death occurring in this way is not uncommon. The effects of some kinds of poison furnish a good illustration of it. There are certain substances which, applied to some part or other of the body, speedily extinguish life: and when, after their fatal operation, the thorax is opened, each chamber of the heart is found to be filled with its proper stimu- lus, upon which it has been unable to contract. This was distinctly made out by Sir Benjamin Brodie, in his able and scientific inves- tigation of the effects of different poisons. You may read with advantage his papers on this subject in the Philosophical Transactions for 1811 and 1812. He ascertained, upon examining the chest after death occasioned by the Upas antiar, that the heart was not empty, but full, . purple blood in its right, and scarlet blood in its left cavities. These are the anatomical characters of this kind of death; and they prove that the action of the heart doc:; not cease from a defect of stimulus, but from a loss of its contractile power. Syncope.—The. state of suspender! animation common to both these forms of dying— (the ultimate external phenomena being nearly the same in each, and the result in each being the simple failure of the circulation)—is often expressed by the term syncope. Besides the essential distinctions between them already mentioned, there is this further point of difference. In death by anffimia, the suspension of the functions of the nervous ten arises from a lack 6f the blood which should be sent to the brain from the heart. Hence the well known effect of me re position. Syncope is sooner produced by venesection