Initial energy supplementation in critically ill patients receiving enteral nutrition: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND AND OBJECTIVES

Here we systematically reviewed and quantitatively analyzed randomized controlled trials (RCTs) to compare the important initial outcomes of critically ill adults receiving low- and highenergy enteral nutrition.

METHODS AND STUDY DESIGN

RCTs comparing low- and high-energy supplementation in critically ill adults receiving enteral nutrition admitted to the intensive care unit for an expected stay of >48 h were included. Abstracts submitted to major scientific meetings were included and the primary endpoint was mortality. The risk ratio (RR) and weighted mean difference (WMD) with 95% confidence intervals (CIs) were the effect measures.

RESULTS

Eleven RCTs (3,212 patients) were included. The groups did not differ significantly in mortality (RR, 0.94; 95% CI, 0.80-1.11; p=0.47), infections morbidity (RR 1.09; 95% CI 0.95-1.26; p=0.23), pneumonia morbidity (RR 1.04; 95% CI 0.88-1.23; p=0.68), hospital length of stay (WMD -0.27; 95% CI -3.21 to 3.76; p=0.88), intensive care unit length of stay (WMD -0.32; 95% CI, -1.81 to 1.16; p=0.46), mechanical ventilation days (WMD -0.30; 95% CI-1.42 to 0.82; p=0.60). The incidence of gastrointestinal intolerance was significantly lower in the low-energy group (RR 0.79; 95% CI 0.65-0.97; p<0.05).

CONCLUSIONS

The initial administration of low- versus high-energy supplements did not impact clinical outcomes except for gastrointestinal intolerance in non-malnourished critically ill patients receiving enteral nutrition. The initial administration of highrather than low-energy may benefit these patients by reducing infections, but this effect might actually be attributable to the concomitant high protein intake.