An experimental inquiry into the pathology and treatment of asphyxia / [John Eric Erichsen].

  • John Eric Erichsen
Date:
1845]
Catalogue details

Licence: Public Domain Mark

Credit: An experimental inquiry into the pathology and treatment of asphyxia / [John Eric Erichsen]. Source: Wellcome Collection.

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    into the proximal end of the left carotid artery of A, and another into that of the right carotid artery of C. These vessels had pre- viously been ligtatured beyond the point at which the pipes were introduced so that no hemorrhage might occur. The force of the heart’s impulse, in the lateral dogs, A and C, was now measured by the heemadynamometer, and found to amount.to from 45 to 5 inches in each of them. A tube, furnished with a stop-cock, was next adapted to the trachea of the centre dog, B, and a pipe was introduced into the distal extremities of both its carotid arteries, which were tied below the point at which the pipes were inserted. The animal did not appear in the least to suffer from the ligature of both these arteries. One of the jugular veins of the centre dog was then exposed, and a ligature was passed under it in order that It might be punctured, so as to avoid the occurrence of plethora and apoplexy, when the carotid arteries of the two lateral dogs were connected with the corresponding vessels of the central one. The pipes in the carotid artery of A and C were then adapted by means of connecting pieces to those in the central dog, and were besides tightly tied together, so that they could not slip dur- ing the struggles of the animal. When this arrangement had been properly and securely made, the trachea of the centre dog was closed, the jugular vein was punctured, and the stop-cocks connecting its carotid arteries with those of the lateral dogs were opened. As soon as this had been done the vertebrals of the dog, B, (the centre one), were compressed with the fingers of an as= sistant, in order that the circulation through the brain might be confined as nearly as possible to arterial blood. ‘The centre dog remained quiet for about a minute and a quarter ; it then began to struggle, and in three minutes all movement had ceased, and ani- mal life was extinct. The distal extremities of the carotid ar- teries of the centre dog were then examined, as they had been se- veral times during the experiment, and were found still to pulsate, although somewhat fecbly, from the impulse of the blood sent di- rect from the hearts of the lateral dogs. Nearly a pint of blood had flowed from the jugular vein during the experiment, so that the animal had clearly not died from plethora. The lateral dogs were both alive, but evidently enfeebled by loss of blood ; and on the pressure in the carotid artery of one of them being measured by the hemadynamometer, it was found to amount to not more than 3 or 34 inches of mercury. The centre dog was opened about ten minutes after its death, by which time the action of the heart had entirely ceased. The lungs were of a gray mottled colour, and much congested, dark drops of blood exuding when they were cut into. The coronary ves- sels were quite black; the right auricle and ventricle and pul- monary artery were distended with black blood. The VENE CAVE VOL. Lxitl. No. 162. B