Glutamine on critical-ill patients: a systematic review and meta-analysis

Background To conduct a meta-analysis of the effect of glutamine supplements on prognosis in adult critical-ill patients. Methods We searched the Web of Science, Cochrane library, PubMed, the Wanfang Database, and the China National Knowledge Infrastructure (CNKI)/CBMdisc database. The primary outcome was hospital mortality, or if not reported, 28-day/6-month/intensive care unit (ICU) mortality. The secondary outcomes were duration of mechanical ventilation (MV), length of stay (LOS) in the ICU, LOS in the hospital, and nosocomial infections. Results In 599 related articles, 47 randomized controlled trials, including 6,198 patients, met all the inclusion criteria. Hospital mortality was not significantly different between the glutamine group and the control group. Length of MV was significantly higher in the control group than that of the glutamine group. In a subgroup analysis of severely burned patients, hospital mortality had the same trend. In other subgroups, there was no significant difference between the two groups. Conclusions We suggest that supplemental glutamine need not be routinely added to the diet of criticalill patients to reduce hospital mortality, with the exception of the diet of severely burned patients.