Achieving Positive Protein Balance in the Immediate Postoperative Period in Neonates Undergoing Abdominal Surgery

Objectives: To determine whether neonates undergoing major abdominal surgical procedures in the first day of life could achieve a positive protein balance without protein toxicity in the immediate perioperative period by using parenteral amino acids and fentanyl analgesia. Study design: Newborns undergoing major surgery for gastroschisis in the first 24 hours of life (n = 13) were alternately allocated to immediate postoperative parenteral administration of 1.5 g/kg^-1/day^-1 versus 2.5 g/kg^-1/day^-1 amino acids. Protein balance was determined at 1.6 to 2.6 days postoperatively with both nitrogen balance and leucine stable isotope methodology. Statistical analyses were conducted with the unpaired t test and linear regression. Results: Protein balance was significantly different in the 2 groups with both nitrogen balance and leucine stable isotope methodology. There was no evidence of protein toxicity as determined with blood urea nitrogen, creatinine, and ammonia concentrations. Conclusions: Neonates undergoing the metabolic stress of abdominal surgery shortly after birth are able to achieve a net positive protein balance with parenteral amino acid administration without evidence of protein intolerance.