Effect of nutritional route on colonic anastomotic healing in the rat

Although early enteral feeding has been shown to benefit cutaneous healing when compared to parenteral feeding, the effect of the route of nutritional support in gastrointestinal anastomotic healing has not been defined. The aim of the present study was to determine whether the route of nutritional support influences colonic anastomotic healing. Twenty male Sprague-Dawley rats weighing 270 to 290 grams underwent identical surgical manipulation co nsisting of central venous catheterization, gastrostomy insertion, and dist al colonic anastomosis (single-layer, inverted). Identical nutrient infusat es composed of 4.25% amino acids, 25% dextrose, and vitamins were administe red, with half the animals receiving the infusions via the gastrostomy and the other half tia the venous catheter. Animals were killed 5 days after su rgery. There were no differences in nutritional parameters between the pare nterally and enterally fed groups. Colonic anastomotic bursting pressure wa s significantly higher in the enterally fed group (180 +/- 6 vs. 150 +/- 11 mm Hg; P < 0.01). The measured insoluble collagen and total protein conten t in anastomotic tissue were enhanced in the enterally supported group. The fraction of soluble (newly synthesized) collagen did not differ between th e two groups. The data demonstrate that the route of nutrient administratio n influences colonic anastomotic healing. The preservation of colonic struc tural collagen in the enteral group may improve the ability of the gut to h old sutures and thus enhance anastomotic healing.