Volume 1
The cyclopaedia of anatomy and physiology / Edited by Robert B. Todd.
- Date:
- 1836-59
Licence: Public Domain Mark
Credit: The cyclopaedia of anatomy and physiology / Edited by Robert B. Todd. Source: Wellcome Collection.
815/832 page 801
![teiTU]>tious of the voice are obviously often due to the state of the respiration. It must not be omitted that in some instances the voice has remained firm to the last. Of the signs of death derived from the organic functions, the first in importance are those belonging to the circulation. The mode in which the action of the heart declines is extremely various, but has for the most part some connexion with the nature of the dis- order. In maladies of considerable duration, and in which for a long time all the func- tions have suffered in a greater or less degree, the cessation of the heart’s motion is nearly always gradual. The number of pulsations may, within a brief period of decease, greatly exceed the natural rate, but their energy is impaired, and the quantity of blood expelled at each systole is very small. In many acute affections the failure is evidenced some- times by increased frequency and diminished vigour of the contractions, and sometimes by their irregularity and frequency, the force being but little altered. In such cases the cause of dis- turbance is, without doubt, in some interruption of the nervous connexions of the organ. In other cases, the heart, before finally ceasing to beat, contracts with great violence, and then rapidly and suddenly comes to a stop. We J;ave frequently noticed this kind of action in diseases of the brain, and have had reason to think that the syncope was brought on by the state of the respiration; the latter effect, how- ever, being itself due in no slight measure to the irregular action of the heart. The increased frequency of the pulsations in a debilitated state of the heart indicates a greater susceptibility to the stimulus of the blood, at the same time that the resulting contractions are less efficient. The period of repose be- tween the diastole and the systole is briefer than in the normal action, besides that less time is occupied by the systole itself, in conse- quence perhaps of the very slight shortening of the fibres. In a vigorous heart the reverse of this takes place; the irritability is not such as to prevent a considerable pause after the dias- tole, and the fibres undergo a much greater degree of shortening. Why the irritability of a part should increase to a certain extent with increasing debility, is a problem yet to be solved. But we have reason to think that it is chiefly in acute diseases that the great rapidity of the heart’s action is presented, and that in chronic affections there is a more gradual ex- haustion of irritability. Inccjualih/ of arte- rial action, when amounting to a great degree, is one of the most threatening symptoms that can be witnessed. We allude particularly to that extraordinary pulsation of the carotids which is sometimes observable, when the ra- dial artery can scarcely be distinguished. It is perhaps one of the strongest presumptions that arteries posse.ss a vital contractility, which may be disturbed in them as in other parts of ffie system. The state of the respiration in a moribund decease; sometimes ceasing gradually, in har- mony with the languishing circulation; but sometimes slow, laborious, and stertorous, and, as Haller expresses it, “ dum anxietas equidem cogit moliri, vetat debilitas.In addition to those causes of struggling respira- tion which belong to the nervous centres and to the circulation in the lungs, the function is often dreadfully embarrassed by the accumu- lation of fluids, mucous, serous, or purulent, in the bronchiae. The quantity of these secre- tions is often increased by a state of the bron- chial membrane, analogous to what we shall notice presently in the skin, designated by Laennec “ the catarrh of the dying;” but the mere accumulation of the natural quantity from defect of those muscular actions which usually remove it, whether in the fibres of Reisseissen, or in the general respiratory appa- ratus, is amply sufficient to cause exquisite distress. Mediate or immediate auscultation detects a loud guggling throughout the chest, which is sometimes audible even at a little distance, and the vibrations of which may be felt by the hand. This sound must not be confounded with the true“ death-rattle,” which is produced not by struggles between air and liquid in the bronchial ramifications, but by the ejection of air from the lungs through the fluid in the trachea. It is often followed by a flow of spumous liquid through the mouth and nostrils. The loss of animal heat occurs first in the extremities,—a fact easily explicable by the smaller quantity of blood sent into them ; but it is probable that the state of the nervous system, and the cessation of the nutritive and other capillary actions, which perform so im- portant a part in calorification, may participate in the production of the result in question. The recession of heat from the limbs was no- ticed by Hippocrates, but his mode of stating the fact in one remarkable passage, his last aphorism, appears considerably affected by his theoretical views of the use of this agent in the economy.-f The secretions present nothing very charac- teristic. If the disorder has been of short duration, they may have undergone no consi- derable change ; but when the declension of life has been more gradual, they are all more or less altered. The bile and the urine are often found in their proper receptacles, of a perfectly healthy character, after a short illness; while in senile dissolution tiiey are almost always scanty and vitiate.l. The generation of gas in large quantities, so as to produce tym- panites, is a very common occurrence at the termination of acute diseases.t We have also noticed loud borborygmi during the last few hours of life, occasioned by large collections of air, and by a preternatural excitement of intestinal irritability, analogous to what we have noticed in the heart and arteries. The • Klcnicntn Pltysiologiic, lib. xxx. ^‘22. t llii)])Ocr. Aph. ^ viii. Itl.](https://iiif.wellcomecollection.org/image/b22005444_0001_0819.jp2/full/800%2C/0/default.jpg)
