Enteral nutrition in circulatory shock: friend or foe?

Purpose of review Circulatory shock is associated with reduced splanchnic blood flow and impaired gut epithelial barrier function (EBF). Early enteral nutrition (EN) has been shown in animal models to preserve EBF. There are limited human data informing early EN in circulatory shock and critical care nutrition guidelines provide disparate recommendations regarding the optimal timing and dose. The purpose of this review is to describe the harms and benefits of early EN in circulatory shock by identifying and appraising recent human data. Recent findings The cumulative risk of nonocclusive bowel ischemia and necrosis in patients with circulatory shock is no higher than 0.3% across observational and randomized controlled trial-level data, and whether the risk is increased by EN delivery remains uncertain. Observational data suggest that early EN in circulatory shock is associated with improved clinical outcomes but data from robust randomized controlled trials remain equivocal, so the optimal timing and dose remain unknown. Based on the best available data, initiating restrictive dose EN into the stomach after initial resuscitation in patients with circulatory shock does not appear to be harmful. In fact, early EN may preserve EBF and improve clinical outcomes.