What do we know about optimal nutritional strategies in children with pediatric acute respiratory distress syndrome?

Nutrition in pediatric acute respiratory distress syndrome (PARDS) is an essential aspect of therapy, with potential to modify outcomes. The gut is slowly establishing its place as the motor of critical illness, and the 'gut-lung' axis has been shown to be in play in the systemic inflammatory response. Thus, utilizing the gut to modify outcomes in PARDS is an exciting prospect. PARDS is associated with high mortality in low- and middle-income countries (LMIC), where malnutrition is also prevalent and may worsen during hospital stay. Mortality may be higher in this subgroup of patients. At present, the gold standard to estimate resting energy expenditure (REE) in critically ill children is indirect calorimetry. However, it is a cumbersome and expensive procedure, as a result of which its routine practice is limited to very few units across the world. Therefore, predictive equations, which may under- or over-estimate REE, are relied upon to approximate calorie and protein needs of children with PARDS. Despite having target calorie and protein requirements, studies have found that a large proportion of critically ill children do not achieve these levels even at the end of a week in pediatric intensive care unit (PICU). The preferred mode of nutrition delivery is enteral, and if possible, early enteral nutrition (EEN). Immunonutrition has been a lucrative subject of research, and while there have been some strides, no therapy has yet conclusively demonstrated benefit in terms of mortality or reduced length of stay in PICU or the hospital. Probable immunonutrients in PARDS include omega-3 fatty acids, arginine, glutamine and vitamin D, though none are a part of any recommendations yet.