Early glutamine-enriched enteral feeding facilitates colonic anastomosis healing: light microscopic and immunohistochemical evaluation.

Problems related to colonic anastomosis healing constitute the major morbidity in colorectal surgery. Patients without appropriate nutritional support are at higher risk of postsurgical complications, mainly due to reduced wound healing. Therefore, we investigated the effect of early and late postoperative total enteral nutrition (TEN) and glutamine addition on colon anastomosis healing using light microscopy and immunohistochemistry (IGF-I immunolabelling). In this study, 40 Wistar-albino rats underwent distal left colonic transection and anastomosis. The rats were then divided into four groups given different diets: delayed total enteral nutrition (dTEN; beginning 3 days postoperatively), delayed TEN with added glutamine (dTEN+Glutamine), early TEN (eTEN; beginning within 6h postoperatively), and early TEN with added glutamine (eTEN+Glutamine). Colon segments, including the anastomosis, were excised 7 days postoperatively and evaluated histopathologically for inflammation, mucosal healing, submucosal-muscular layer repair, the amounts of necrosis and vascularisation and immunohistochemically for IGF-I labelling. The inflammation and necrosis scores in the dTEN and dTEN+Glutamine groups were significantly greater than in the eTEN and eTEN+Glutamine groups. The IGF-I immunoreactivity increased in the eTEN, eTEN+Glutamine, and dTEN+Glutamine groups compared to dTEN (p<0.05). We concluded that early TEN and glutamine enrichment in the postoperative period improve anastomosis healing via IGF-I.