EFFECTS OF AN IMMUNE-ENHANCING DIET IN CRITICALLY INJURED PATIENTS

Objective: To determine the effects of an immune-enhancing experimenta l diet (XD = supplemental arginine, trace elements, and increased omeg a-3 fatty acids) versus standard diet (SD), on immune cell function an d clinical outcome of critically injured patients Design: Prospective randomized clinical trial of patients admitted to the surgical intensi ve care unit after trauma (Injury Severity Score > 13), Materials and Methods: Patients received early enteral nutrition with either XD or S D for a minimum of 5 days, Measurements: Mortality, intensive care uni t, ventilator, and hospital days, as well as incidence of adult respir atory distress syndrome (ARDS) and infectious complications were recor ded, Nutritional parameters were also studied, Peripheral blood leukoc ytes were isolated from normal volunteers and from patients on days 1, 6, and 10 of feeding, Main Results: Demographics and injury severity were similar in both groups, Both SD (n = 21) and XD (n = 22) groups r evealed depressed monocyte function (tumor necrosis factor, prostaglan din E-2, and procoagulant activity) on day 1 compared with a reference group (p < 0.05), However, monocytes from XD patients began to ''norm alize'' their response (tumor necrosis factor, prostaglandin E-2, and procoagulant activity) by day 6, Although ARDS occurred more frequentl y in the XD group (45 vs, 19%), the majority of ARDS in both groups oc curred very early, with only three patients in the XD (13.6%) and one patient in the SD (4.7%) groups developing ARDS after study entry, XD patients remained on the ventilator longer (16.4 vs, 9.7 days) and in the hospital longer (32.9 vs, 22 days) compared with the SD group, but overall mortality was nearly identical (4,5 vs, 5%), Conclusion: The exact role and timing for diets with immune-enhancing effects has yet to be defined.