Colonic anastomosis: Evaluation of an end-to-end crushing and inverting technique

Abstract

SUMMARY Two anastomotic techniques of the colon were evaluated in the dog. An end-to-end simple interrupted crushing suture pattern and an end-to-end interrupted inverting (Connell) suture pattern were used with 3-0 polyglycolic acid as the suture material. Results of clinical evaluations, lasting 28 days, identified no differences between the 2 techniques. Postoperative complications were not encountered during the 28 days. Daily monitoring of hematologic values and temperature demonstrated normal stress responses to the surgical insult, but differences were not noted between the surgical groups. Evaluations of adhesion formation at necropsy (28th day) showed no statistical difference between the 2 groups, nor were the hematologic values associated with peritonitis and resulting adhesion formation. Adhesions were minimal and did not grossly interfere with mechanical function of the intestines. Stenosis was marked with the inverting suture pattern, accounting for an average 63% loss of the lumen diameter at the anastomotic site. The crushing pattern averaged 30% loss of diameter. Even though the lumen size at the anastomoses was greatly reduced with the inverting pattern, clinical significance between the 2 groups was not noted. Bursting pressure studies at postsurgical day 28 showed that the inverting suture pattern achieved equal normal intestinal strength, whereas the crushing technique was significantly weaker. All but 3 specimens burst on the anastomotic line, and all burst on the antimesenteric border. Histopathologic evaluations at postsurgical day 28 indicated that the end-to-end crushing pattern had less inflammatory response at the anastomosis. Mucosa bridged the anastomotic site and the remaining layers were aligning themselves with minimal fibrous tissue proliferation. The inverting pattern maintained a bud of granulation tissue at the anastomotic site. The mucosa did not bridge this area. Inflammatory cells and fibrous tissue proliferation at the anastomotic site were marked in comparison to the crushing pattern. Despite these findings, neither technique was proved to be clinically superior in conditioned research dogs.