Randomised trial of glutamine, selenium, or both, to supplement parenteral nutrition for critically ill patients

Objective To determine whether inclusion of glutamine, selenium, or both in a standard isonitrogenous, isocaloric preparation of parenteral nutrition influenced new infections and mortality among critically ill patients. Design Randomised, double blinded, factorial, controlled trial. Setting Level 2 and 3 (or combined) critical care units in Scotland. All 22 units were invited, and 10 participated. Participants 502 adults in intensive care units and high dependency units for >= 48 hours, with gastrointestinal failure and requiring parenteral nutrition. Interventions Parenteral glutamine (20.2 g/day) or selenium (500 mu g/day), or both, for up to seven days. Main outcome measures Primary outcomes were participants with new infections in the first 14 days and mortality. An intention to treat analysis and a prespecified analysis of patients who received >= 5 days of the trial intervention are presented. Secondary outcomes included critical care unit and acute hospital lengths of stay, days of antibiotic use, and modified SOFA (Sepsis-related Organ Failure Assessment) score. Results Selenium supplementation did not significantly affect patients developing a new infection (126/251 v 139/251, odds ratio 0.81 (95% CI 0.57 to 1.15)), except for those who had received >= 5 days of supplementation (odds ratio 0.53 (0.30 to 0.93)). There was no overall effect of glutamine on new infections (134/250 v 131/252, odds ratio 1.07 (0.75 to 1.53)), even if patients received >= 5 days of supplementation (odds ratio 0.99 (0.56 to 1.75)). Six month mortality was not significantly different for selenium (107/251 v 114/251, odds ratio 0.89 (0.62 to 1.29)) or glutamine (115/250 v 106/252, 1.18 (0.82 to 1.70)). Length of stay, days of antibiotic use, and modified SOFA score were not significantly affected by selenium or glutamine supplementation. Conclusions The primary (intention to treat) analysis showed no effect on new infections or on mortality when parenteral nutrition was supplemented with glutamine or selenium. Patients who received parenteral nutrition supplemented with selenium for >= 5 days did show a reduction in new infections. This finding requires confirmation.