Non-occlusive acute intestinal vascular failure

Abstract

Summary The records of 87 patients with vascular intestinal insufficiency leading to gangrene were analysed in retrospect. In 77 patients the cause of the vascular insufficiency could be determined. In 25 per cent no organic obstruction to blood flow was found in the macroscopic intestinal vessels. The patients with non-occlusive intestinal gangrene showed a tendency to be younger and to have associated cardiac infarction more frequently than those with vessel obstructions. Moreover, non-occlusive intestinal gangrene was found more frequently following a period of systemic arterial hypotension. A history of atrial fibrillation and digitalis therapy was present with equal frequency in both groups of patients. Based on these cases and on current animal experimental data, it is suggested that the bowel gangrene seen in non-occlusive ischaemia is due to short-circuiting of oxygen at the base of the villi in the villous counter-current exchanger. This mechanism becomes much more effective in hypotension owing to reduced velocity of the villous blood flow. The possibility is emphasized that, with a coexisting atherosclerotic narrowing in the mesenteric vascular tree, cardiovascular disturbances which are themselves not enough to alter central arterial pressure, may none the less induce regional hypotension. Such regional hypotension could lead to villous destruction and initiate a vicious circle which ends in generalized gangrene of the bowel.