Observations on aneurism of the abdominal aorta / [Alexander Monro].

  • Alexander Monro
Date:
1827
Catalogue details

Licence: Public Domain Mark

Credit: Observations on aneurism of the abdominal aorta / [Alexander Monro]. Source: Wellcome Collection.

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    OF THE NEW CHANNEL BY WHICH THE BLOOD FLOWS TO THE BOWELS OF THE PELVIS, AND TO THE INFERIOR EXTREMI¬ TIES, WHEN THE ABDOMINAL AORTA IS IMPERVIOUS. The case which fell under my notice, affords a striking ex¬ ample of the circulation being carried on, when none of the blood reached the bowels of the pelvis or inferior extremities, by the medium of the trunk of the aorta ; and also, that the blood may be diverted from its usual channel, without a derange¬ ment of the functions of that part of the body which is usually supplied by the aorta. The blood probably reached the pelvis and inferior extre¬ mities of the body by different channels ; a part of it, by the anasto¬ mosis between the internal mammary and epigastric arteries, ano¬ ther part of it by the medium of the anastomoses between the phrenic, lumbar, ileo-lumbar, and circumflex arteries, and by the anastomoses between the ascending branches of the gluteal and lumbar arteries ; and I conceive that but a small part of the blood found its way downwards by the anastomoses between the inter¬ nal mammary and epigastric arteries; as there must be a consider¬ able impediment to the free flow of blood bv that channel, for the usual current of the blood is then reversed,—for, instead of the blood rising upwards towards the internal mammary artery, as in the natural circulation, it must have descended through the epigas¬ tric artery towards the inferior extremities, by which the natural course of the blood is reversed. If aneurism in the abdominal aorta be seated between the origin of the superior and inferior mesenteric arteries, I am led to suppose, from a preparation in my Museum, in which a li¬ gature had been thrown around the descending aorta of a living dog, and, from the consequent enlargement of the anastomosing branch between the superior and inferior mesenteric arteries, and also by the result of the following experiment, made upon a dead body, that a considerable portion of the blood flows downwards by that channel. I divided the abdominal aorta ; one pipe was fixed into the upper portion, and another into the lower portion of that vessel, b 2
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