A randomized trial of intravenous glutamine supplementation in trauma ICU patients.

Purpose: To evaluate the effect of the intravenous (i.v.) L-alanyl-L-glutamine dipeptide supplementation during 5 days on clinical outcome in trauma patients admitted to the intensive care unit (ICU).

Methods: This was a prospective, randomized, double-blind, multicenter trial. Glutamine was not given as a component of nutrition but as an extra infusion. The primary outcome variable was the number of new infections within the first 14 days.

Results: We included 142 patients. There were no differences between groups in baseline characteristics. Up to 62 % of the patients in the placebo group and 63 % in the treatment group presented confirmed infections (p = 0.86). ICU length of stay was 14 days in both groups (p = 0.54). Hospital length of stay was 27 days in the placebo group and 29 in the treatment group (p = 0.88). ICU mortality was 4.2 % in both groups (p = 1). Sixty percent of the patients presented low glutamine levels before randomization. At the end of the treatment (6th day), 48 % of the patients maintained low glutamine levels (39 % of treated patients vs. 57 % in the placebo group). Patients with low glutamine levels at day 6 had more number of infections (58.8 vs. 80.9 %; p = 0.032) and longer ICU (9 vs. 20 days; p < 0.01) and hospital length of stay (24 vs. 41 days; p = 0.01).

Conclusions: There was no benefit with i.v. L-alanyl-L-glutamine dipeptide supplementation (0.5 g/kg body weight/day of the dipeptide) during 5 days in trauma patients admitted to the ICU. The i.v. glutamine supplementation was not enough to normalize the plasma glutamine levels in all patients. Low plasma glutamine levels at day 6 were associated with a worse outcome.