Inadequate energy and protein supply in children undergoing cardiopulmonary bypass surgery: current problems and future direction

Abstract

Objective It has been increasingly realized that perioperative nutritional support plays an important role in improving clinical outcomes in children with congenital heart disease(CHD) undergoing cardiopulmonary bypass surgery. The purpose of this review was to examine the nutritional conditions in perioperative CHD children and the main problems in nutritional management in the cardiac intensive care unit(CICU), based on which further directions were proposed. We found that preoperative malnutrition is common. This limited research of energy and protein is further compounded by the complex metabolic alterations with hyper-metabolism, hyper-catabolism and hypo-anabolism in the early postoperative course. Knowledge about energy and protein metabolism and requirements in post-CPB children remains much limited. The current nutritional 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 CHD infants. Nitrogen balance is recommended to assess 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. A paradigm should be shifted toward individualized nutrition prescription in the context of a specific CICU feeding algorithm.