Diathermy-induced inflammation does not affect suture holding capacity of intestinal anastomoses

We compared the suture holding capacity of rat intestinal anastomoses after division of the bowel with scissors or diathermy. Two sets of experiments differing in suture technique were done. In one set the amount and solubility of anastomotic collagen were measured, and neutrophil accumulation quantified with a myeloperoxidase (MPO) assay. MPO activity 24 h after surgery was 60% higher (p less than 0.05) after division with diathermy than after division with scissors. Suture holding capacity (breaking strength) decreased by approximately 70% (p less than 0.001) in both groups when sutures were inserted near the bowel edges, while no decrease was noted when sutures were inserted at a farther distance, regardless of the mode of bowel division. After 7 days MPO levels approached baseline values in both groups and the bowel always ruptured outside the anastomosis. Collagen content was not adversely affected by diathermy. Although the reduction in early anastomotic strength may be mediated by local neutrophil activity, suture holding capacity was not influenced by the increased neutrophil accumulation elicited by diathermy.