COMPARISON OF MEASURED AND PREDICTED ENERGY-EXPENDITURE IN MECHANICALLY VENTILATED CHILDREN

Objective: To determine che energy requirements in mechanically ventil ated pediatric patients using indirect calorimetry and to compare the results with the predicted metabolic rate, Design: In 50 mechanically ventilated children with a moderate severity of illness: energy expend iture was measured by indirect calorimetry. Daily caloric intake was r ecorded fur all patients, Total urinary nitrogen excretion was determi ned in 31 patients, Results: Although there was a close correlation be tween the measured total energy expenditure (mTEE) and the predicted b asal metabolic rate (pBMR) (r = 0.93, p < 0.001) Bland-Altman analysis showed lack of agreement between individual mTEE and pBMR values. The ratio of caloric intake/mTEE was significantly higher in the patients with a positive nitrogen balance (1.4 +/- 0.07) compared with those w ith a negative nitrogen balance (0.8 +/- 0.1, p < 0.001), Conclusions: Standard prediction equations are not appropriate to calculate the en ergy needs of critically ill, mechanically ventilated children. Indivi dual measurements of energy expenditure and respiratory quotient by me ans of indirect calorimetry in combination with nitrogen balance are n ecessary for matching adequate nutritional support.