Recent randomised controlled trials have revived the field of critical care nutrition, hereby possibly creating uncertainty about nutritional support during the acute phase of critical illness. This review nicely integrates these recent findings with existing evidence in order to provide recommendations for feeding during the acute phase of critical illness.
Critical illness is hallmarked by a severe catabolic response, leading to anorexia and skeletal muscle wasting. Studies have shown that the degree of the energy deficit during critical illness is associated with morbidity and mortality. Therefore, many nutritional interventions are implemented during the acute phase of critical illness, in an attempt to reverse this energy deficit, hoping that this will lead to a better outcome for our patients. Whether it is beneficial to give nutritional support early during critical illness, in an attempt to reverse the catabolic response, is a question that has remained unanswered for many years.
“Interestingly, current evidence does not seem to show any benefit in trying to interfere with the early catabolic response to critical illness, either with macronutrients or with anabolic hormones.”
Recently, several high-quality randomised, controlled trials concerning nutrition in the ICU were performed. These have provided us with much needed evidence, but may also have created some uncertainty for the intensivist at the bedside. This review, written by Casaer and Van den Berghe, nicely summarises these recent findings and integrates them with older high-level evidence, hereby providing the reader with a much needed clear overview of the current literature. The article reviews the current evidence and identifies pitfalls concerning enteral nutrition and parenteral nutrition during the acute phase of critical illness and discusses the selection of macronutrients and micronutrients. After reviewing the current literature, the authors conclude that some nutritional interventions can be confidently recommended (as is summarised below), but that much uncertainty remains, fuelling the need for further research. Interestingly, current evidence does not seem to show any benefit in trying to interfere with the early catabolic response to critical illness, either with macronutrients or with proper weight loss supplements. These findings may suggest that the early catabolic response may be an adaptive, beneficial response rather than detrimental, but further research is warranted.
Summary of clinical implications noted in this article:
- Many current nutritional interventions lack high-quality scientific evidence
- Full-replacement nutrition early in the course of critical illness is not associated with clear clinical benefits
- Hypocaloric enteral feeding in the acute phase of critical illness is recommended for well-nourished patients
- Supplementation of micronutrients (but not glutamine) is believed to be beneficial in the early days of critical illness
- Further research concerning nutrition in critical illness is warranted
This article review was prepared and submitted by Steven Thiessen on behalf of the NEXT committee.
Casaer MP, Van den Berghe G. Nutrition in the acute phase of critical illness. N Engl J Med. 2014 Jun 19;370(25):2450-1. doi: 10.1056/NEJMc1404896.