Effect of early postoperative feeding on the healing of colon anastomoses in the presence of intra-abdominal sepsis in rats

PURPOSE: Intra-abdominal infection is generally considered a major risk fac tor for dehiscence of primary colon anastomosis. To elucidate the indicatio ns for nutritional support during intra-abdominal sepsis, we investigated t he healing of anastomoses in an animal model. METHODS: Twenty male Sprague- Dawley rats (280-320 g) underwent cecal ligation and single puncture. After 24 hours the perforated cecum was removed, and the left colon was transect ed and anastomosed in a single-layer inverted fashion. Animals were randoml y assigned to receive both chow and water (early-fed group; n = 10) or wate r alone for the first 72 hours and chow thereafter (late-fed group; n = 10) . Colon-bursting pressure was measured five days after the anastomosis, at which time the anastomosis was excised. RESULTS: The survival rate after ce cal ligation and single puncture was 100 percent, and blood cultures were p ositive in 20 percent of animals five days after surgery. All data are expr essed as means +/- standard error of the mean. Body weight increased more i n the early-fed group than in the Late-fed group (15.6 +/- 3 vs. -6.3 +/- 2 .8 g; P < 0.001). Early feeding resulted in increased anastomotic bursting pressure (200 +/- 11 vs. 161 +/- 12 mmHg; P < 0.05) and total collagen conc entration at the site of anastomosis (2.36 +/- 0.09 vs. 2.01 +/- 0.07 mu g/ mg wet tissue; P < 0.01) compared with the late-fed group. CONCLUSION: Earl y feeding has a positive effect on anastomotic healing in the presence of i ntraabdominal sepsis. The mechanism by which early feeding enhances the col onic anastomotic healing is unclear, although preservation of colonic colla gen seems to play a significant role.