Objective: To evaluate the effect of early enteral nutrition on the outcome of critically ill and injured patients.
Data sources: MEDLINE, citation review of relevant primary and review articles, personal files, and contact with expert informants.
Study selection: Randomized, controlled studies that compared early with delayed enteral nutrition in hospitalized adult postoperative, trauma, head-injured, burn, or medical intensive care unit (ICU) patients. From 161 articles screened, 27 were identified as randomized, controlled trials comparing early with delayed enteral nutrition and were included for data extraction. Of these, 12 were excluded. None of the studies included medical ICU patients.
Data extraction: Fifteen studies containing 753 subjects were analyzed. Descriptive and outcome data were extracted independently from the articles by the two reviewers. Main outcome measures were infections, noninfectious complications, length of hospital stay, and mortality. The meta-analysis was performed using the random effects model.
Data synthesis: Early enteral nutrition was associated with a significantly lower incidence of infections (relative risk reduction, 0.45; 95% confidence interval, 0.30-0.66; p =.00006; test for heterogeneity, p =.049) and a reduced length of hospital stay (mean reduction of 2.2 days; 95% confidence interval, 0.81-3.63 days; p =.004; test for heterogeneity, p =.0012). There were no significant differences in mortality or noninfectious complications between the two groups of patients.
Conclusions: The results of this meta-analysis support the experimental data demonstrating the benefit of the early initiation of enteral nutrition. The results of this meta-analysis must, however, be interpreted with some caution because of the significant heterogeneity between studies.