Does the addition of glutamine to total parenteral nutrition have beneficial effect on the healing of colon anastomosis and bacterial translocation after preoperative radiotherapy?

Abstract

Glutamine administration stimulates mucosal growth and preserves the morphology of the intestine. Theoretically, it could improve colonic anastomotic healing after radiotherapy (RT)-induced epithelial damage and mucosal atrophy induced by total parenteral nutrition (TPN). To investigate this issue, the rectosigmoid colon in male Wistar rats was irradiated to a total dose of 25 Gy. Five days after the end of RT, side-to-side anastomosis was constructed between the irradiated rectosigmoid and the nonirradiated caecum. Postoperatively, animals were divided in three groups: group I, normal diet orally; group II, TPN; group III, TPN enriched with 2% glutamine (Gln-TPN). All animals decreased in weight during RT and after surgery. Weight regain postoperatively was better in the orally fed animals in comparison with the parenterally fed animals (I vs. II and III; p < 0.01). Colonic anastomotic bursting pressure (BP) and bursting wall tension (BWT) were significantly less in group II in comparison with groups I and III (II vs. I and III; p < 0.01). BP and BWT were comparable in groups I and III. No significant differences were found between all the groups in gut bacterial translocation to the blood or to the mesenterical lymph nodes. Conclusively, Gln-TPN can play a role in counteracting the negative effect of food deprivation on the healing of irradiated colonic anastomoses. Postoperative Gln-TPN does not influence gut bacterial translocation in this rat model.