Effetto della via di somministrazione e della formulazione dei supporti nutrizionali postoperatori sulla risposta metabolico-immunitaria e sull'outcome postoperatorio

Objective: To study the effect of the route of delivery and the formulation of the postoperative nutritional support on host defense, protein metabolism, infectious complications, and outcome. Methods: This was a prospective, randomised, clinical trial involving two hundred and sixty subjects who were candidate for pancreatoduodenectomy or gastrectomy for cancer. The patients were randomly allocated to three groups during surgery. Starting 6 hours after operation, the first group received a standard enteral formula (standard group; n = 87); the second the same enteral formula enriched with arginine, omega-3 fatty acids, and RNA (immunonutrition group; n = 87), and the third total parenteral nutrition (parenteral group; n = 86). The three regimens were isocaloric and isonitrogenous. The nutritional goal was 25 kcal/kg/day. Immune response was studied by the phagocytosis ability of polymorphonuclear cells (PMNs), interleukin 2 receptors (IL-2R), delayed hypersensitivity response (DHR) as well as protein synthesis by interleukin 6 (IL-6) and prealbumin (PA). Tolerance of enteral feeding, incidence of postoperative complications, and length of hospital stay (LOS) were also reduced. Results: Subjects receiving immunonutrition had a significantly better recovery of the immune parameters, a reduced synthesis of IL-6 and and increased production of PA on postoperative day 8 compared to the other two groups. Only 6.3% of the enterally fed patients did not reach the nutritional goal. The postoperative infection rate was 14.9% in the immunonutrition group, 22.9% in the standard group, and 27.9% in the parenteral group (p = 0.06). LOS was 16.1 ± 6.2 days, 19.2 ± 7.9, and 21.6 ± 8.9 in the immunonutrition, standard and parenteral group, respectively (p <0.005). Conclusion: Early postoperative enteral feeding is a valid alternative to parenteral nutrition in surgical patients. Immunonutrition ameliorates the immune response, induces a switch from acute phase proteins to constitutive proteins, and improves outcome.