Nutrition in the Neurocritically Ill Patient

Patients suffering neurocritical illness present with unique and challenging clinical issues which require a multidisciplinary approach to improve outcomes. Optimal nutrition is of the utmost importance and must not be overlooked. During critical illness, a complex cascade of inflammatory and immune reactions precipitate a hypercatabolic state. The liver is signaled to transition protein synthesis from albumin to acute phase reactants. As the body does not maintain a surplus of readily available amino acids, muscle is catabolized to provide substrates for this process. Sufficient macronutrients, namely protein, must be provided to sustain a favorable nitrogen balance. All patients admitted to the NeuroICU should be evaluated for nutrition risk utilizing the NUTRIC or NRS-2002 score. Resting energy expenditure (REE) should be obtained using indirect calorimetry (IC). However, if IC is not available, predictive equations may be substituted. Accurate prediction of REE is essential to providing appropriate amounts of macronutrients as over- and underfeeding can lead to significant clinical problems. Early enteral nutrition is recommended in nearly all critically ill patient populations. When starting nutrition, it is important to be able to identify refeeding syndrome as this is a potential lethal condition. While enteral nutrition may be associated with diarrhea, we do not recommend holding nutrition if this ensues—unless there are additional concerning clinical signs—as holding feeds can often lead to malnutrition. Instead, a comprehensive evaluation should be performed prior to stopping nutrition. Supplementation with immunomodulating nutrients has been shown to be effective in selected patient populations and is the focus of ongoing research.