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.