The Incidence of Colonic Ischemia with Retroperitoneal Aortic Reconstruction: A Prospective Study Emphasizing Early Selective Endoscopic Intervention

Abstract

Colonic ischemia is a significant complication following aortic reconstruction. The incidence of colon ischemia following transabdominal aortic repair is reported to be between 0.5% and 10% for overt ischemia with operative mortality ranging between 48% and 100%. It has been suggested that aortic repair utilizing the retroperitoneal approach may be associated with an increased incidence of colonic ischemia. A prospective study on all patients undergoing retroperitoneal aortic replacement was performed between July 1, 1995, and June 30, 1996. Patients meeting predetermined criteria were evaluated with flexible sigmoidoscopy. In this period, 202 patients (mean age 73 years) underwent retroperitoneal aortic replacement. One hundred and twenty-four (61%) patients were operated on for aneurysmal disease, 17 (8.4%) had symptomatic or ruptured aneurysms, and 61 (30%) had aortic occlusive disease. Colonic viability was assessed intraoperatively with visual inspection and Doppler ultrasound. Flexible sigmoidoscopy was performed in 20 (9.9%) patients between 24 hours and 15 days after aortic reconstruction. Indications for flexible sigmoidoscopy included guaiac-positive stool, unexplained fever, acidosis or leukocytosis, hypotension, and abdominal pain or distention. Eight (4.0%) patients had endoscopically proven colonic ischemia. Of these patients, aortic repair was performed on four patients with aortic occlusive disease and on two patients each with asymptomatic and ruptured aneurysms. Transmural necrosis requiring operation and bowel resection was identified in four patients, two patients with occlusive disease, and two patients with asymptomatic aneurysms. The other four patients had mucosal ischemia managed nonoperatively. Operative mortality rate following bowel resection was zero. Colonic ischemia remains a significant cause of mortality following aortic replacement. However, retroperitoneal aortic replacement does not contribute to an increased incidence of colonic ischemia. Selective, early endoscopy may improve survival with prompt recognition and treatment.