Objective: To study the effect of the route of delivery and formulation of postoperative nutritional support on host defense, protein metabolism, infectious complications, and outcome.
Design: Prospective, randomized, clinical trial.
Setting: Department of Surgery at a university hospital.
Patients: Two hundred sixty candidates for pancreaticoduodenectomy or gastrectomy for cancer.
Interventions: Patients were randomly allocated into 3 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 3 regimens were isocaloric and isonitrogenous. The nutritional goal was 105 kJ/kg per day.
Main outcome measures: Immune response by phagocytosis ability of polymorphonuclear cells, interleukin (IL)-2 receptor levels, and delayed hypersensitivity response; protein synthesis by IL-6 and prealbumin; tolerance of enteral feeding; incidence of postoperative complications; and length of hospital stay.
Results: The immunonutrition group had a significantly better recovery of the immune parameters on postoperative day 8 compared with the other groups. Linear regression analysis showed an inverse correlation between IL-6 and preambulin levels (r = 0.766) only in the immunonutrition group. Only 11 patients (6.3%) in both enteral groups did not reach the nutritional goal. Postoperative infection rate was 14.9% (13/87) in the immunonutrition group, 22.9% (20/87) in the standard group, and 27.9% (24/86) in the parenteral group (P = .06). Mean +/- SD length of hospital stay was 16.1 +/- 6.2, 19.2 +/- 7.9, and 21.6 +/- 8.9 days in the immunonutrition, standard, and parenteral groups, respectively (P = .01 vs standard group; P = .004 vs parenteral group).
Conclusions: Early postoperative enteral feeding is a valid alternative to parenteral feeding in patients undergoing major surgery. Immunonutrition enhances the host response, induces a switch from acute-phase to constitutive proteins, and improves outcome.