Total Energy Expenditure, Protein Kinetics, and Body Composition in Recovering Burn Children.

Two pre-dose urine specimens will be collected prior to an oral dose containing 0.22 g/kg total body water of 100% 18O water (or 1.2 g/kg per body weight of 10% 18O water) and 0.11 g/kg per body weight of 99.9% deuterium oxide. Then the patient will receive a single dose (4mg/kg, less than 2% of normal daily intake of 1.1g per person) of 15N glycine tracer. For this, patients will drink a dose of 15N glycine (4mg.kg 1dissolved in 20 ml of saline) mixed in 50 cc of apple juice or other liquid beverage, followed by a 50 cc wash of water. 24 hour urine collection will commence immediately. Twenty-four hour urines will be used for determining the 15N NH3 and 15N urea enrichment. Each urine container will contain 5 ml of 15N HCl for trapping the urinary ammonium. Urine will be collected each day for 3 days, for determination of the total urinary nitrogen, urea creatinine, and ammonia excretion.