The effect of enteral versus parenteral nutrition for critically ill patients: A systematic review and meta-analysis

Study objective: To analyze the effect of enteral nutrition compared with parenteral nutrition in critically ill patients. Design: Systematic review and meta-analysis of randomized controlled trials. Setting: Intensive care unit. Patients: 23 trials containing 6478 patients met our inclusion criteria. Intervention: A systematical literature search was conducted to identify eligible trials in electronic databases including PubMed, Embase, Scopus, EBSCO and Cochrane Library. The primary outcome was mortality, the secondary outcomes were gastrointestinal complications, bloodstream infections, organ failures, length of stay in ICU and hospital. We performed a predefined subgroup analyses to explore the treatment effect by mean age, publication date and disease types. Main results: The result showed no significant effect on overall mortality rate (OR 0.98, 95%CI 0.81 to 1.18, P = 0.83, I-2 = 19%) and organ failure rate (OR 0.87, 95%CI 0.75 to 1.01, P = 0.06, I-2 = 16%). The use of EN had more beneficial effects with fewer bloodstream infections when compared to PN (OR 0.59, 95%CI 0.43 to 0.82, P = 0.001, I-2 = 27%) and this was more noteworthy in the subgroup analysis for critical surgical patients (OR 0.36, 95%CI 0.22 to 0.59, P < 0.0001, I-2 = 0%). EN was associated with reduction in hospital LOS (MD -0.90, 95%CI -1.63 to -0.17, P = 0.21, I-2 = 0%) but had an increase incidence of gastrointestinal complications (OR 2.00, 95%CI 1.76 to 2.27, P < 0.00001, I-2 = 0%). Conclusion: For critically ill patients, the two routes of nutrition support had no different effect on mortality rate. The use of EN could decrease the incidence of bloodstream infections and reduce hospital LOS but was associated with increased risk of gastrointestinal complications.