Study of Energy Requirements in Critically Ill Newborns

PROTOCOL OUTLINE: Patients are assigned to one of three groups according to gestational age (24-28 weeks estimated gestational age (EGA) vs 29-34 weeks EGA vs 35 weeks EGA and over) and severity of respiratory illness (need for high frequency ventilation vs stable conventional ventilator settings or extubated within past 24 hours vs no need for mechanical ventilation).

Patients receive water labeled with deuterium and oxygen O 18 by mouth or by gastrostomy tube on days 1 and 7. Urine samples are collected prior to the first dose, 4-6 hours after the first dose, and then every 24 hours until the second dose. All urine is collected for 4-6 hours after the second dose. Samples are analyzed by dual inlet isotope ratio mass spectrometry.