The effect of indirect calorimetry guided isocaloric nutrition on mortality in critically ill patients-a systematic review and meta-analysis.

Indirect calorimetry (IC)-guided nutrition might positively affect the clinical outcome of critically ill patients. In this systematic review and meta-analysis, our objective was to assess the benefit of isocaloric nutrition guided by IC, compared to hypocaloric nutrition, for critically ill patients admitted to the intensive care unit (ICU). We performed a systematic review of all randomized controlled trials published through January 2021, assessing the benefit of isocaloric nutrition guided by IC. The primary outcome was 28-day all-cause mortality. Secondary outcomes were ICU and 90-day all-cause mortality, rate of nosocomial infections, and adverse events. Four trials evaluating 1052 patients were included. Patients treated with isocaloric nutrition had a lower 28-day mortality rate (risk ratio (RR) 0.79, 95% confidence interval (CI) 0.63-0.99, P = 0.04). No between-group difference was found in ICU and 90-day mortality (RR 0.92, 95% CI 0.68-1.23, P = 0.56 and RR 0.88, 95% CI 0.72-1.07; P = 0.2, respectively) and in the rate of nosocomial infections (RR 1.15, 95% CI 0.77-1.72, P = 0.51). A pooled analysis of studies that evaluated the benefit of isocaloric nutrition guided by IC, for critically ill patients in the ICU, has shown reduced 28-day mortality. However, there was no difference in 90-day mortality and nosocomial infection rate.