Small intestinal submucosa for reinforcement of colonic anastomosis

Different materials have been evaluated for anastomotic reinforcement to prevent gastrointestinal anastomotic leakage. In this experimental study, small intestinal submucosa (SIS) was tested as a sealing for stapled colonic anastomosis in a porcine model. The aims of this study were to determine the macroscopic and microscopic outcomes and to evaluate the safety and feasibility of applying SIS for anastomotic sealing.

Circular stapled anastomoses were performed in 18 pigs. Standard anastomosis in the control group (n = 8) was compared to an SIS-sealed anastomosis in the study group (n = 10). After 30 days, anastomotic segments were examined for macroscopic and microscopic regeneration and their resistance to mechanical stress. Furthermore, animal survival and clinical course were evaluated.

None of the animals developed anastomotic leakage, intraabdominal abscess, or peritonitis. Shrinkage of SIS was evident in nine of ten animals. Encapsulation and displacement of the SIS patches were seen in two animals. Quantity of anastomotic granulation tissue and rate of complete mucosal coverage of anastomotic line were increased in SIS-sealed anastomoses without reaching significance. Moreover, no significant differences were found in the rate of survival of the animals, anastomotic stricture formation, intraabdominal adhesions, anastomotic bursting pressure, and microscopic healing parameters of the anastomosis between stapled colonic standard anastomosis and anastomosis protected by SIS.

The results of this study indicate a safe use of SIS for anastomotic reinforcement in a porcine model. Adverse effects like strictures, increased adhesions, and anastomotic abscesses were absent. Promoting effects on colonic wound healing by SIS were microscopically evident. The results argue for a careful clinical evaluation in humans.