We have developed a water-sealed infant calorimeter (IC) system which uses the techniques of closed-circuit spirometry to measure oxygen consumption (VO2) in premature and full-term infants. Carbon dioxide production (VCO2) is simultaneously calculated from the effluent mixed expired CO2 and the circulating flowrate. Respiratory Quotient (RQ) and Energy Expenditure (EE) are then calculated from the primary data. Measurement of VO2, VCO2, and calculation of RQ were +/- 5.0% of predicted values determined by burning ethyl alcohol or volume extraction and CO2 infusion in our bench model. Measurement in 11 premature infants produced mean values for VO2 and VCO2 of 8.5 +/- 2.5 ml/min/kg and 8.5 +/- 2.4 ml/min/kg, respectively. This system is noninvasive, does not interfere with infant tube feedings or iv infusions, and permits safe, long-term monitoring of the infant's metabolic activity. It allows a more exact matching or oral or intravenous feedings to the actual energy expenditure of the infants, and offers potential advantages for the nutritional management of sick infants.

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AIM: We evaluated the use of prenatal steroids (PNS) and the effect of that practice on hospital mortality of late preterm infants with complex congenital heart defects (CHD). METHODS: Retrospective review of records of late preterm infants with complex CHD infants that were cared for in a single tertiary perinatal center between 2002 and 2009. Multivariate logistic regression analysis was performed to determine which of the risk factors commonly associated with death prior to discharge from the hospital predict the outcome (hospital death). RESULTS: Of the 106 late preterm infants with complex CHD, 31(29%) died and 15 (14%) received PNS. Endotracheal intubation in the delivery room (42% vs 15%), necrotizing enterocolitis (10% vs 0%) and hypoplastic left heart syndrome (52% vs 25%) were statistically more frequent in non-surviving infants. Non-surviving infants were more frequently treated with PNS (23% vs 11%) but this difference was not statistically significant (p = 0.131). Using logistic regression analysis, delivery room intubation (OR 4.91;) and the hypoplastic left heart syndrome (OR 3.29; 95% CI 1.28 -8.48), but not prenatal steroids were independently associated with increased risk of hospital death. CONCLUSIONS: In a selected population of late preterm infants with complex CHD, prenatal steroid treatment did not independently influence survival.