Clinical and protein metabolic efficacy of glutamine granules-supplemented enteral nutrition in severely burned patients

As an abundant amino acid in the human body, glutamine has many important metabolic roles that may protect or promote tissue integrity and enhance the immune system. A relative deficiency of glutamine in such patients could compromise recovery and result in prolonged illness and an increase in late mortality. The purpose of this clinical study is to observe the effects of enteral supplement with glutamine granules on protein metabolism in severely burned patients. Forty-eight severe burn patients (total burn surface area 30-75%, full thickness burn area 20-58%) who met the requirements of the protocol joined this double-blind randomized controlled clinical trial. Patients were randomly divided into two groups: burn control group (B group, 23 patients) and glutamine treated group (Gln group, 25 patients). There was isonitrogenous and isocaloric intake in both groups, glutamine and B group patents were supplemented with glutamine granules or placebo (glycine) at 0.5 g/kg per day for 14 days with oral feeding or tube feeding, respectively. The level of plasma glutamine, plasma protein content, urine nitrogen and urine 3-methylhistidine (3-MTH) excretion were determined, wound healing rate of the burned area and hospital stay were recorded. The results showed that there were significant reductions in plasma glutamine level and abnormal protein metabolism. After supplement with glutamine granules for 14 days, the plasma glutamine concentration was significantly higher than that in B group (607.86 ± 147.25 μmol/L versus 447.63 ± 132.38 μmol/L, P < 0.01) and the plasma prealbumin and transferrin in Gln group were remarkably higher than those in B group (P < 0.01), but the concentration of total protein and albumin were not significantly changed compared with B group (P > 0.05). On the other hand, the amount of urine nitrogen and 3-MTH excreted in Gln group were significantly lower than that in B group. In addition, wound healing was faster and hospital stay days were shorter in Gln group than B group (46.59 ± 12.98 days versus 55.68 ± 17.36 days, P < 0.05). These indicated that supplement glutamine granules with oral feeding or tube feeding could abate the degree of glutamine depletion, promote protein synthesis, inhibit protein decompose, improve wound healing and reduce hospital stay.