Replanting the inferior mesentery artery during infrarenal aortic aneurysm repair:: Influence on postoperative colon ischemia

Background: Replanting the inferior mesentery artery (IMA) to prevent ischemic colitis (IC) has been discussed for many years; yet, to our knowledge, no prospective studies have been conducted to compare the incidence of histologically proven IC in patients with and without IMA revascularization. The aim of this prospective study, with histologic evaluation of the sigmoid colon mucosa, was to assess the influence of replanting the IMA on IC and mortality. Methods: Front January 1999 to December 2003, 160 consecutive patients who were operated on for a symptomatic (n = 21) or asymptomatic (n = 139) infrarenal aortic aneurysm were prospectively assessed and randomly assigned either to replanting or ligating the IMA. Sigmoidoscopy with biopsy was performed on day 4 or 5 after surgery; an autopsy was performed on patients not surviving to day 5 after surgery. All patients gave written informed consent. Results: Of the 160 randomized patients, 128 had a confirmed patent IMA and formed the basis of this study. Their age was 70 8 years (men, 70 8 years; women, 73 7 years). The IMA was replanted in 67 patients (52%) and ligated in 61 (48%) intraoperatively. IC developed in six patients with a replanted IMA and in 10 with a ligated IMA (relative risk [RR], 0.55; 95% confidence interval [CI], 0.21 to 1.41; chi(2) = 1.62; P =.203). Blood loss in the two cohorts did not differ significantly (P =.788); however, patients with IC had a significantly higher blood loss compared with the cohort without IC (P =.012) and were older (P =.017). Age, sex distribution, clamping time, the use of tube or bifurcated grafts, and intraoperative hypotension did not differ between patients with ligated or replanted IMA. Conclusion: Although replanting the IMA did not confer a statistically significant reduction of perioperative morbidity or mortality in this study, it appears that older patients and patients with increased intraoperative blood loss might benefit from IMA replantation, because this maneuver does not increase perioperative morbidity or substantially increase operation time.