Impact of the structure and dose of protein intake on clinical and metabolic outcomes in critically ill children: A systematic review.

OBJECTIVE: The aim of this study was to describe the effects of structure/type and total amount of protein intake on protein balance and clinical outcomes in critically ill children.

METHODS: We conducted a systematic review of relevant literature on Embase, PubMed/Medline, Web of Science, Scopus, and Latin American and Caribbean Health Sciences. A partial gray literature search was undertaken and the reference lists of the selected articles were searched manually. Observational and clinical trials that evaluated the total protein intake, structure of the protein source, or both, in critically ill children were included. Nitrogen balance and clinical outcomes (mortality, length of stay, and duration of mechanical ventilation) were the main outcomes of interest.

RESULTS: We found 18 eligible studies, of which 17 assessed the quantity and one described protein structure in relation to the outcomes. In all, 2118 pediatric critically ill patients <18 y of age were included. The total daily protein intake ranged from 0.67 to 4.7 g/kg. Average daily total protein intake >1.1 g/kg, especially >1.5 g/kg, was associated with positive protein balance and lower mortality.

CONCLUSION: In critically ill children, total daily protein intake >1.1 g/kg was associated with positive effects on clinical outcomes and protein balance. The existing data are not sufficient for determining the optimal structure of protein delivered by enteral route in critically ill children.