Impact of withholding early parenteral nutrition in adult critically ill patients on ketogenesis in relation to outcome

Excerpt

Withholding parenteral nutrition until one week after intensive care unit (ICU) admission (late-PN) was previously shown to accelerate recovery and reduce infections in critically ill adults and children, as compared to early supplementing insufficient enteral feeding with parenteral nutrition (early-PN) [1, 2]. In a detailed secondary analysis of the pediatric PEPaNIC randomized controlled trial (RCT), we previously identified enhanced ketogenesis as potential mediator of part of this outcome benefit. Indeed, late-PN increased plasma concentrations of the ketone 3-hydroxybutyrate (3HB) up to sixfold, with a peak effect on day 2 [3]. Increased 3HB independently associated with an accelerated weaning from mechanical ventilation and a shorter time to live ICU discharge. These associations remained significant after adjusting for ketogenic regulators, suggesting a direct mediator role [3]. …