Absence of hypermetabolism after operation in the newborn infant.

This study was designed to assess the effect of operative stress on resting energy expenditure (REE) in the newborn infant. In 13 neonates who had an uncomplicated abdominal, thoracic, or spinal operation, REE was measured both preoperatively and on the third postoperative day. The mean preoperative REE of 43.19 +/- 7.95 kcal/kg per day was not significantly different from the mean postoperative REE of 41.70 +/- 7.94 kcal/kg per day. Sixteen neonates had REE measured on the first, second, and seventh postoperative days. The mean postoperative REE values of 43.12 +/- 6.92, 42.41 +/- 7.58, and 46.33 +/- 6.89 kcal/kg per day at 1, 2, and 7 days, respectively, were not significantly different from the preoperative REE. There was no significant difference in oxygen consumption, carbon dioxide production, and respiratory quotient between the preoperative and postoperative groups. In this study, an uncomplicated operation did not increase REE in the neonate.