Colonic ischemia complicating open vs endovascular abdominal aortic aneurysm repair

Objective: Colonic ischemia (CI) is a known complication of both open abdominal aortic aneurysm (AAA) repair and endovascular aneurysm repair (EVAR). Despite a relatively low incidence of 1% to 6%, the associated morbidity and mortality are high. We sought to analyze factors that affect the development of CI on the basis of type of repair as well as associated outcomes from a large nationwide database. Methods: All admissions undergoing AAA repair were selected from the 2003 and 2004 Nationwide Inpatient Sample. Univariate and logistic regression analyses were used to compare outcome measures and identify independent predictors of development of colonic ischemic complications. Results: We identified 89,967 admissions for AAA repair (mean age, 69.9 years). Open elective repair was performed in 49% of cases, elective EVAR in 41%, and ruptured aneurysm repair in 9%. The overall incidence of CI was 2.2% (1941 cases); however, the incidence for specific procedures was significantly higher after repair of ruptured aneurysm (8.9%) and open elective repair (1.9%) than after EVAR (0.5%; both P < .001). Patients who developed CI were at increased risk for mortality (37.8% vs 6.7%), had longer hospital stays (21.5 vs 8.1 days), incurred higher hospital charges ($182,000 vs $77,000), and were less likely to be discharged home from hospital (36% vs 71%; all P < .001). Independent predictors of development of CI included ruptured aneurysm (odds ratio [OR] = 6.4), female gender (OR = 1.6) and, in the setting of elective repair, open operation (OR = 3.1). CI was found to be a strong independent predictor of mortality in evaluations of both the entire cohort (OR = 4.5) and the elective open repair and EVAR (OR = 2.4) subgroups. Conclusions: CI is significantly more common after open AAA repair and is associated with increased morbidity and a two- to fourfold increase in mortality.