title: A systematic literature review and meta-analysis of randomized clinical trials of parenteral glutamine supplementation.
abstract: OBJECTIVE
  Glutamine supplementation has been associated with reduced mortality, infections and hospital length of stay in critically ill patients and patients undergoing major surgery. We carried out a meta-analysis to examine randomized clinical trial (RCT)-based evidence of these effects.
  
  
  METHODS
  Based on a systematic database search, RCTs published since 1990 were included if they evaluated the effect of parenteral glutamine supplementation against a background of parenteral nutrition. Enteral (tube) feeding in a proportion of patients was allowable. Information on RCT methodology, quality and outcomes was extracted. Random effects meta-analysis followed the DerSimonian-Laird approach.
  
  
  RESULTS
  Forty RCTs were eligible for meta-analysis. Parenteral glutamine supplementation was associated with a non-significant 11% reduction in short-term mortality (RR = 0.89; 95% CI, 0.77-1.04). Infections were significantly reduced (RR = 0.83; 95% CI, 0.72-0.95) and length of stay was 2.35 days shorter (95% CI, -3.68 to -1.02) in the glutamine arms. Meta-analysis results were strongly influenced by one recent trial. An element of publication bias could not be excluded.
  
  
  CONCLUSIONS
  Parenteral glutamine supplementation in severely ill patients may reduce infections, length of stay and mortality, but substantial uncertainty remains. Unlike previous meta-analyses, we could not demonstrate a significant reduction in mortality.
authors.affiliation: Institute of Social and Preventive Medicine, Medical Economics Unit, University of Zurich, Hirschengraben 84, 8001 Zurich, Switzerland. lea.bollhalder@ifspm.uzh.ch
authors.forename: Lea
authors.initials: L
authors.lastname: Bollhalder
authors.forename: Alena M
authors.initials: AM
authors.lastname: Pfeil
authors.forename: Yuki
authors.initials: Y
authors.lastname: Tomonaga
authors.forename: Matthias
authors.initials: M
authors.lastname: Schwenkglenks
mesh_terms: D016638:Critical Illness; D019587:Dietary Supplements; D005973:Glutamine / Q000008:administration & dosage*; D006801:Humans; D007902:Length of Stay; D010288:Parenteral Nutrition; D016032:Randomized Controlled Trials as Topic
chemical_list: D005973:Glutamine