Objective
To test the hypothesis that total energy expenditure would be significantly higher in ELBW infants near discharge compared with healthy term infants.
Study design
This study was designed to determine total energy expenditure and body composition in a group of ELBW infants nearing discharge on full volume enteral feedings of fortified breast milk or post-discharge formula (Neosure™) (n=10, birth weight 0.8±0.1kg, gestation 26±0.8 wk, age at study 68±9 d, postconceptional age 36±1wk) and compare them with healthy term newborns all receiving breast milk (n=14, birth weight 3.5±0.5 kg, gestation 39.0±1.4 wk, age at study 2.3±1 d). Body composition and total energy expenditure were measured using the doubly labeled water method over a 7 day period.
Results
The total energy expenditure for ELBW infants was significantly higher than in term infants (89±22 kcal/kcal/kg/day vs. 58±19 kcal/kg/d (p≤0.001)). Total energy expenditure normalized to fat free mass was also significantly greater in ELBW infants (98±3 kcal/kg/d compared with 73±20 kcal/kg/d (p ≤0.01)).
Conclusions
Rates of total energy expenditure in ELBW infants nearing discharge are greater than normal healthy term infants. Higher energy intakes in the ELBW infants compensated for the higher rates of total energy expenditure in the ELBW infants.