Nutrition in critical illness: a current conundrum

Critically ill people are unable to eat. What’s the best way to feed them? Nutrition authorities have long recommended providing generous amounts of protein and calories to critically ill patients, either intravenously or through feeding tubes, in order to counteract the catabolic state associated with this condition. In practice, however, patients in modern intensive care units are substantially underfed. Several large randomized clinical trials were recently carried out to determine the clinical implications of this situation. Contradicting decades of physiological, clinical, and observational data, the results of these trials have been claimed to justify the current practice of systematic underfeeding in the intensive care unit. This article explains and suggests how to resolve this conundrum.

Causes and consequences of interrupted enteral nutrition: a prospective observational study in critically ill surgical patients

BACKGROUND

Malnutrition and underfeeding are major challenges in caring for critically ill patients. Our goal was to characterize interruptions in enteral nutrition (EN) delivery and their impact on caloric debt in the surgical intensive care unit (ICU).

MATERIALS AND METHODS

We performed a prospective, observational study of adults admitted to surgical ICUs at a Boston teaching hospital (March-December 2012). We categorized EN interruptions as "unavoidable" vs "avoidable" and compared caloric deficit between patients with ≥1 EN interruption (group 1) vs those without interruptions (group 2). Multivariable logistic regression was used to investigate the association of EN interruption with the risk of underfeeding. Poisson regression was used to investigate the association of EN interruption with length of stay (LOS) and mortality.

RESULTS

Ninety-four patients comprised the analytic cohort. Twenty-six percent of interruptions were deemed "avoidable." Group 1 (n = 64) had a significantly higher mean daily and cumulative caloric deficit vs group 2 (n = 30). Patients in group 1 were at a 3-fold increased risk of being underfed (adjusted odds ratio, 2.89; 95% confidence interval [CI], 1.03-8.11), had a 30% higher risk of prolonged ICU LOS (adjusted incident risk ratio [IRR], 1.27; 95% CI, 1.14-1.42), and had a 50% higher risk of prolonged hospital LOS (adjusted IRR, 1.53; 95% CI, 1.41-1.67) vs group 2.

CONCLUSIONS

In our cohort of critically ill surgical patients, EN interruption was frequent, largely "unavoidable," and associated with undesirable outcomes. Future efforts to optimize nutrition in the surgical ICU may benefit from considering strategies that maximize nutrient delivery before and after clinically appropriate EN interruptions.