Energy expenditure in extremely low birth weight infants near time of hospital discharge.

OBJECTIVE: To test the hypothesis that total energy expenditure is significantly higher in extremely low birth weight (ELBW) infants compared with healthy term infants near the time of discharge. STUDY DESIGN: This study was designed to determine total energy expenditure and body composition in a group of ELBW infants nearing discharge receiving full-volume enteral feedings of fortified breast milk or postdischarge formula (Neosure) (n = 10; mean birth weight, 0.8 +/- 0.1 kg; mean gestational age, 26 +/- 0.8 weeks; mean age at study, 68 +/- 9 days; mean postconceptional age, 36 +/- 1 weeks) and compare them with healthy term newborns all receiving breast milk (n = 14; mean birth weight, 3.5 +/- 0.5 kg; mean gestational age, 39.0 +/- 1.4 weeks; mean age at study, 2.3 +/- 1 days). Body composition and total energy expenditure were measured using the doubly labeled water method over a 7-day period. RESULTS: Mean total energy expenditure was significantly higher in the ELBW infants compared with the term infants (89 +/- 22 kcal/kg/day vs 58 +/- 19 kcal/kg/day; P