An experimental inquiry into the pathology and treatment of asphyxia ... To which the Royal Humane Society awarded the Fothergillian Gold Medal / [John Eric Erichsen].

  • Erichsen, John Eric, 1818-1896.
Date:
1845
Catalogue details

Licence: Public Domain Mark

Credit: An experimental inquiry into the pathology and treatment of asphyxia ... To which the Royal Humane Society awarded the Fothergillian Gold Medal / [John Eric Erichsen]. Source: Wellcome Collection.

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    blood circulating through the brain. Dr. Reid shewed the fallacy of the experiments that wrere adduced by Dr. Kay in support of his doc¬ trine, and proved satisfactorily that the suspension of the functions of the encephalon is chiefly, if not entirely, dependent upon the circula¬ tion of venous blood through its arteries. Not that the venous blood exercises any positively deleterious influence, but rather that it acts by the deprivation of the natural stimulus of arterial blood; the functions of the brain rapidly manifesting themselves when arterial blood is readmitted, provided this be done in a given time. It has likewise been proved by this physiologist that the functions of the cerebral hemispheres are annihilated a short time before those of the medulla oblongata, the respiratory movements continuing for a short time after the animal has become quite insensible. I may state generally, without analyzing the evidence on which these statements are founded, that it is in complete accordance with what I have had frequent occasion to observe in my experiments on as¬ phyxia. The mode in which death occurs, and the order in which the vital functions cease in asphyxia, appear to be as follow:—The blood, whilst it is assuming a venous character, passes for some time with tolerable freedom through the vessels of the lungs into the left side of the heart, whence it is propelled through the whole svstem, causing first a derangement and then a suspension of the functions of the sensorium, so that the animal becomes more and more insensible ; perfect unconsciousness and cessation of all voluntary movement occurring in about a minute and a half or two minutes. The func¬ tions of the medulla oblongata are continued for some little time longer. The blood having now become perfectlv venous begins to be obstructed in its passage through the ultimate ramifications of the pulmonary veins and of the arterial system generally, occasioning congestions of the pulmonary artery, of the right cavities of the heart and of the whole of the venous system, and the quantity sent to the left side of the heart becomes materially lessened. The ob¬ struction in the vessel goes on increasing, and coincident with this is a diminution in the activity of the heart’s action, which becomes both slower and feebler in consequence of the lessened quantity and altered quality of the blood that finds its way into the left ventricle and that is propelled into the coronary arteries, until at last, from a concurrence of these several causes, stagnation of the blood in the vessels of the lungs, diminution in the quantity and alteration in the quality of the blood supplied to the substance of the heart, and dis¬ tention of the right auricle and ventricle, this organ ceases to con¬ tract, and organic life becomes extinct. Before concluding this part of the paper, it may be as well to mention the average period at which I have found, in the course of a considerable number of observations, some of the principal pheno¬ mena of asphyxia occur.