Transient episodes of sigmoid ischemia and their relation to infection from intestinal organisms after abdominal aortic operations.

We examined the possibility that disruption of the mucosal barrier confining bacteria to the lumen of the colon, which occurs during the transient episodes of sigmoid ischemia after abdominal aortic operations, might be causally related to the appearance of infections from intestinal organisms. Six (18%) of 33 patients after elective operations developed transient sigmoid ischemia identified by the development of acidosis in the sigmoid colon wall on the day of operation and the appearance of guaiac-positive liquid stool a few days after the surgery. Three patients developed infections from intestinal organisms, all of whom had an antecedent episode of sigmoid ischemia (p less than .004, Fisher's exact test). The degree of acidosis in the wall of the sigmoid colon on the day of surgery was greater (p less than .004) and the duration longer (p less than .004) in these patients than in the others. The duration of sigmoid ischemia was the best predictor of infection (p less than .0001). These data are consistent with the hypothesis in question.