Glutamine administration reduces Gram-negative bacteremia in severely burned patients: a prospective, randomized, double-blind trial versus isonitrogenous control

Abstract

Objective: To determine the effect of intravenous glutamine supplementation vs. an isonitrogenous control on infectious morbidity in severely burned patients. Previous clinical studies in seriously ill patients suggest a beneficial effect of glutamine on infectious morbidity, but no trials have examined possible clinical benefits in severely burned patients.

Design: Prospective, double-blind, randomized trial.

Setting: Burn intensive care unit of a university hospital.

Patients: Twenty-six severe burn patients with total burn surface area of 25% to 90% and presence of full-thickness burns. Patients were evaluated for occurrence of bacteremia and antibiotic use during the first 30 days of their burn unit admission. Nutritional status and overall inflammation were also measured.

Intervention: Either intravenous glutamine or an isonitrogenous control amino acid solution was administered as a continuous infusion during burn intensive care unit stay.

Measurements and main results: The incidence of Gram-negative bacteremia was significantly reduced in the glutamine-supplemented group (8%) vs. control (43%; p <.04). No difference was seen in the incidence of Gram-positive bacteremia or fungemia. Average number of positive blood cultures, antibiotic usage, and mortality rates also were reduced but did not reach statistical significance. Significant improvements in serum transferrin and prealbumin were observed in glutamine-supplemented patients at 14 days after burn injury (p <.01 and.04, respectively). C-reactive protein was also significantly reduced at 14 days after burn injury in the glutamine group (p <.01).

Conclusions: Significantly fewer bacteremic episodes with Gram-negative organisms occurred in the glutamine-supplemented patients. Glutamine supplementation improved measures of nutrition and decreased measures of overall inflammation. In addition, a trend toward lower mortality rate, decreased overall bacteremia incidence, and antibiotic usage in the glutamine group was observed. Glutamine's beneficial effects may be a result of improved gut integrity or immune function, but the precise mechanism of glutamine's protection is unknown.