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.

[Early enteral and glutamine enriched enteral feeding ameliorates healing of colonic anastomosis: experimental study]. / Erken enteral ve glutaminli enteral beslenmenin kolon anastomoz iyilesmesine etkisi: Deneysel çalisma.

BACKGROUND: To investigate the effects of postoperative early enteral and glutamine enriched enteral feeding on the healing of experimental colonic anastomosis. METHODS: Forty Wistar-albino rats were equally divided into 4 groups. Colonic transsection and anastomosis situated at the distal left colon was performed on all animals. Animals in groups 1 and 2 received late total enteral nutrition (TEN) and in groups 3 and 4 early TEN. Glutamine was added to TEN protocol in groups 2 and 4. The colonic segment including the anastomosis was excised at the end of the 7th day postoperatively. Bursting pressure of the anastomosis and tissue hydroxyproline levels were determined. RESULTS: Bursting pressure levels were 111.6 and 95.8 centimeters of water (cmH(2)O) in early and late nutrition groups, respectively (p=0.022). Comparison of late TEN groups showed a significant difference in favor of group with glutamine (95.8 vs 138.5 cmH(2)O; p<0.0001). Highest bursting pressures (139 and 138.5 cmH(2)O) were measured in both early and late TEN groups with glutamine. Tissue hydroxyproline level in early TEN group (2440.3 microg) was significantly higher than late TEN group (1509.6 microg; p=0.024). Comparison of late TEN groups showed a considerable but not statistically significant difference (p=0.276) in favor of group with glutamine (1509.6 vs 1981.6 microg). CONCLUSION: Postoperative early TEN significantly ameliorates the resistance of the anastomosis and collagen synthesis. Glutamine enrichment in nutritional protocol decreases and reverses the disadvantages of late TEN regarding the resistance of anastomosis. A similarly positive, albeit weaker, effect of glutamine supplementation is also seen on collagen synthesis.