Energy and Protein Requirements in Children Undergoing Cardiopulmonary Bypass Surgery: Current Problems and Future Direction.

Congenital heart disease (CHD) is 1 of the most common congenital malformations, and considerable numbers of infants and young children with CHD undergo cardiopulmonary bypass surgery. It has been increasingly realized that perioperative nutrition support plays an important role in improving clinical outcomes. The purpose of this review, by searching PubMed, was to examine the nutrition conditions in perioperative children with CHD and the main problems in nutrition management in the cardiac intensive care unit (CICU), based on which future directions were proposed. We found that preoperative poor nutrition status is common. This limited reserve of energy and protein is further compounded by the complex metabolic alterations with hypermetabolism, hypercatabolism, and hypoanabolism in the early postoperative course. Knowledge about energy and protein metabolism and requirements in children after cardiopulmonary bypass remains very limited. The current nutrition recommendations in the CICU are based on little evidence. Insufficient energy and protein supply to meet demands remains a norm in the immediate postoperative period. The commonly used predictive equations do not provide accurate estimate of energy requirement in individual patients during the highly dynamic postoperative course. Indirect calorimetry can provide the best estimate of energy requirements for children with CHD in the CICU. Measurement of nitrogen balance is the recommended method to determine the minimal protein requirement. During the early postoperative period, daily measurements of resting energy expenditure using indirect calorimetry and nitrogen balance in each individual child are essential to optimize energy and protein supply to meet requirements.