Enteral Nutrition Versus a Combination of Enteral and Parenteral Nutrition in Critically Ill Adult Patients in the Intensive Care Unit: An Overview of Systematic Reviews and Meta-Analysis

Background/Objectives: Uncertainty persists about the best methods and timing for providing medical nutrition therapy (MNT) in the acute phase of critical illness. We conducted an overview of systematic reviews to examine and appraise the findings of the current systematic reviews and performed an updated meta-analysis incorporating newly published randomized controlled trials (RCTs) to investigate whether enteral nutrition (EN) is superior to the combination of EN and parenteral nutrition (PN) in patients admitted to the intensive care unit (ICU). Methods: We systematically searched three databases to retrieve systematic reviews and RCTs. Two independent reviewers performed the screening, data extraction, and quality assessment processes. The random effects model was utilized to synthesize the data regarding primary and secondary outcomes. Results: There was no difference between the two interventions regarding the efficacy and safety endpoints, apart from the bloodstream infections, which were found to be increased in the group that received the combination of EN+PN (RR = 1.27, 95%CI = 1.03 to 1.56, PI = 0.91 to 1.77, I2 = 0%). Conclusions: According to the present overview of systematic reviews and meta-analyses, there was no observed benefit on mortality, length of ICU stay or hospitalization, and duration of mechanical ventilation in critically ill patients receiving a combination of EN and PN in comparison to those receiving sole enteral nutrition in the ICU. Furthermore, no difference was observed in the rates of respiratory infections as well as the appearance of adverse events, such as vomiting and diarrhea. On the other hand, there was an increase in bloodstream infection rates in patients who received EN+PN compared to EN alone. Due to the limited implications of the results in clinical practice, further research is needed.