Early versus Late Parenteral Nutrition in Critically Ill Children

Published - Written by Ravi Parikh, M.D., M.P.P.

16During our intensive care unit rotations as residents, patient nutrition is a daily talking point. While it is easy to get lost in the details of the critical illnesses that bring patients to the ICU, we are regularly asked by attendings, nurses, and others, “how are we going to feed this patient?” Indeed, nutrient deficiencies are associated with poor outcomes such as infection, prolonged intubation, and delayed recovery. Our natural inclination is to start feeding early – delaying nutrition can only be bad, right? In adults, this question was addressed in a 2011 randomized controlled trial published in NEJM. That study showed that patients receiving late parenteral (IV) nutrition had faster recovery while in the ICU and fewer complications when compared to those receiving early parenteral nutrition, without a difference in mortality. Based on that trial, early nutrition in critically ill adults may not be such a good thing. But does the same effect hold in children, who are growing and whose nutritional requirements per kilogram are greater than those of adults?

In this week’s issue of NEJM, Fivez et al., the same group that published the 2011 trial, report the results of a multi-center randomized controlled trial that attempts to answer this question. Investigators enrolled children admitted to a participating pediatric ICU (PICU) and deemed at risk for nutritional deficiency according to the STRONGKids nutritional screening tool and whose expected PICU stay was  >24 hours. Children who had been readmitted or who were premature newborns were excluded. From 2012-2015, 1440 of 7519 children screened were randomized to receive either early parenteral nutrition (the standard of care), initiated within 24 hours after PICU admission or late parenteral nutrition, starting on day 8 of PICU admission. In both groups, enteral nutrition – generally via nasogastric tube – was initiated early per local guidelines.

The investigators found that children (median age 1.2 years old) receiving early parenteral nutrition had nearly 8% more new infections (p<0.001) – usually bloodstream or airway infections – and a 2.7-day longer PICU length of stay (p=0.002) than children receiving late parenteral nutrition. These effects were more pronounced among children at higher risk of nutritional deficiency on admission. In an analysis of secondary outcomes, death, readmission within 48 hours, and serious adverse events rates were similar in the two groups. Interestingly, late parental nutrition reduced the length of mechanical ventilation and the odds of renal replacement therapy – two markers of poor prognostic outcomes in ICU patients. Importantly, the impact of late parenteral nutrition was consistent across diagnoses, illness severity, centers, and age of the child.

Thus, the findings reported by Fivez et al. provide evidence against the use of early parenteral nutrition in critically ill children admitted to the PICU. These results are likely to change practice regarding the timing of initiation of parenteral nutrition in children. However, the study doesn’t tell us whether early enteral nutrition is harmful, and additional studies should investigate this question. In the accompanying editorial, Nilesh Mehta, Director of Critical Care Nutrition at Boston Children’s Hospital, rightly notes that “the presupposition that a uniform approach would apply to all [children] is too simplistic.” While the results of the Fivez et al. study may lead to recalibration of when parenteral nutrition is initiated, prescription of nutrition in children must be individualized to their condition, expected nutritional deficiency, and other important variables.

Don’t miss the NEJM Quick Take video summary on this study: 

Browse more From Pages to Practice »