Colon ischemia accompanying ruptured abdominal aortic aneurysm

Abstract

Myocardial, cerebral, and renal ischemia are recognized as serious sequelae in patients surviving repair of ruptured abdominal aortic aneurysms. Colonic ischemia, though a documented consequence of aortic reconstruction, has received less emphasis in these patients. In a 5-year review of a single hospital's experience, 50 patients underwent an emergency operation for ruptured abdominal aortic aneurysm. Ninety-six percent of the patients were in shock preoperatively. Of the 37 patients who survived the initial surgical procedure, 12 (32%) were subsequently found to have colon ischemia diagnosed by proctoscopy, repeat laparotomy, or autopsy. Among 20 of the initial survivors who later died at intervals up to 6 weeks after aneurysm repair 8 (40%) had colon ischemia as the sole or major contributing cause of death. Because of the high incidence of this serious but remediable problem in patients undergoing emergency operation for ruptured abdominal aortic aneurysm, we now routinely perform: (a) intraoperative Doppler examination of the colonic arterial tree, with consideration of mesenteric revascularization if necessary, (b) daily postoperative sigmoidoscopy and examination of the stool for blood, and (c) aggressive “second-look” laparotomy in patients exhibiting any signs or symptoms suggesting colonic infarction. Our experience suggests that large bowel infarction is a common, lethal, and underemphasized complication following successful repair of ruptured abdominal aortic aneurysms.