Effect of the wrapping of experimentally induced ischemic colonic anastomoses with the amniotic membrane on anastomosis safety in rats.

Objective: Colonic anastomotic leakage represents a complication with high mortality and morbidity. In the present study, it was aimed to examine the effect of the amniotic membrane on the healing of ischemic colonic anastomosis.

Methods: 25 pregnant Wistar albino rats aged 19-21 days were randomly divided into 5 groups. With midline laparotomy, pregnancies were terminated, and fresh amniotic membranes were obtained. In Group 1 Sham (S), no procedure except for laparotomy was performed. In Group 2 of colonic anastomosis (A), the descending colon was completely transected and anastomosed. In Group 3 of amniotic anastomosis (AA), the anastomosis line was fixed by being wrapped with the fresh amniotic membrane. In Group 4 of colonic ischemic anastomosis (IA), the marginal arteries were ligated after descending colon transection. Ischemia was induced, and anastomosis was performed. In Group 5 of colonic ischemic anastomosis wrapped with the amniotic membrane (AIA), after ischemic colonic anastomosis was performed, the anastomosis line was fixed by being wrapped with the amniotic membrane. On the postoperative 7th day, rats were sacrificed, and their anastomotic bursting pressures were measured. For histological examination, the colon segment containing the anastomosis line was removed. Hematoxylin-eosin and Van Gieson trichrome stained specimens were histologically evaluated and scored according to the Ehrlich-Hunt model.

Results: Anastomotic bursting pressures were measured in group S as the highest, in AA, AIA, A in a decreasing order and in group IA as the lowest. The difference between groups S and AA was statistically insignificant in the paired comparison of groups according to their bursting pressure values (p=0.222). When the other pairs were compared, the difference between the groups was calculated as significant (p< 0.05). According to the Ehrlich-Hunt model, the total score was the highest in AIA group, decreased in AA, IA, A groups in a decreasing order, and was the lowest in group S. A paired comparison for total scores between the groups was statistically insignificant between groups S and A (p=0.222). Other paired comparisons were statistically significant (p< 0.05).

Conclusion: Wrapping the colon anastomosis line with the amniotic membrane gave positive results both in the ischemic colon as well as in the non-ischemic colon in terms of bursting pressure and histological anastomosis safety.