The Changes Of The Colonic Physiologic Functions After Colonic Anastomosis With A Deeradable Stent In A Norcine Model

Objective The procedure of colonic anastomosis with a degradable stent has been proved simple, feasible, and safe in our porcine model. This study evaluates its impact on the colonic physiologic functions.Methods 20 pigs were assigned randomly to either a stent anastomosis group (SA, n=10) or a conventional anastomosis group (CA, n=10). A colonic anastomosis with a degradable stent was performed in the SA group, and conventional hand-sewn anastomosis was performed in the CA group. The body weight and the fecal weight, the pH of colonic juice, the abdominal adhesion, the total colonic transit time, the immunohistochemistry analysis of interstitial cells of Cajal, the plasma lipopolysaccharide/diamine oxidases/D-lactate levels, the morphological change of tight junction and the Western Blot analysis of occludin were evaluated before and after anastomosis.Results There were no death or severe complications occurred during the experiment. No observable colonic paralysis or retention occurred and no obvious diarrhea or constipation was observed in any pigs. No significant difference of the body weight between both groups was detected at any time. Yet for the fecal weight, that was less in the CA group on the 7th postoperative day. For the abdominal adhesion and the total colonic transit time, there was no significant difference between both groups at any time. The immunohistochemical stain of the interstitial cells of Cajal was more profound and outnumbered on the 30th postoperative day than that on the 14th postoperative day. The integrated optical density of interstitial cells of Cajal showed no significant difference between groups on either the 14th or the 30th postoperative day. The plasma lipopolysaccharide/diamine oxidases/D-lactate levels were remarkably elevated after operation. But, there was either no significant difference between both groups at any time. The electron density of tight junction under transmission electron microscope was lower on the 14th postoperative day, with a more profound gap. For both groups, the expression of occludin after surgery was not significantly different from their pre-surgery levels.Conclusions This procedure of colonic anastomosis with a degradable stent was supposed to be as same as the conventional hand-sewn procedure in their impact on the main components of colonic physiologic functions.