Aerosolized ribavirin in mechanically ventilated children with respiratory syncytial virus lower respiratory tract disease: a prospective, double-blind, randomized trial.

OBJECTIVE: To study the effect of ribavirin aerosol therapy on the immediate clinical course of mechanically ventilated children with respiratory syncytial virus lower respiratory tract disease. DESIGN: Prospective, randomized, double-blind, placebo-controlled study. SETTING: Pediatric intensive care unit (ICU) of a university teaching hospital. PATIENTS: Forty-one children requiring mechanical ventilation for respiratory syncytial virus lower respiratory tract disease. INTERVENTIONS: Patients were stratified by the presence or absence of and underlying disease and then randomized to receive aerosolized ribavirin (20 mg/mL) or saline for 18 hrs/day for 5 days or until endotracheal extubation, whichever came first. MEASUREMENTS AND MAIN RESULTS: Dependent variables included the time course of the illness and the change in FIO2, ventilatory rate, PaO2/FIO2 ratio, and ventilatory-efficiency index of patients while they received aerosol therapy. Ribavirin- and placebo-treated patient groups were not significantly different in the number of ventilator days (6.4 +/- 6.9 vs. 8.2 +/- 10.1; p = .5), oxygen days (10.8 +/- 7.7 vs. 12.2 +/- 11.8; p = .9), ICU days (7.9 +/- 7.0 vs. 10.3 +/- 11.0; p = .7), or hospital days (12.9 +/- 9.7 vs. 16.2 +/- 14.0; p = .6) after the initiation of aerosol therapy. The change in FIO2, ventilatory rate, PaO2/FIO2 ratio, or ventilatory-efficiency index did not differ between the two groups. No ventilator malfunction was observed. There were six deaths caused by intractable hypoxemia in patients with underlying cardiopulmonary disease. Four of these deaths were in the placebo group and two in the ribavirin group (p = .5). CONCLUSIONS: Ribavirin aerosol therapy can be safely administered to mechanically ventilated children with severe respiratory syncytial virus lower respiratory tract disease. However, this therapy does not appear to affect immediate clinical outcome in such patients.

Oxygen consumption, energy expenditure, and substrate utilization after cardiac surgery in children.

OBJECTIVE: To determine the oxygen consumption (VO2), resting energy expenditure, and substrate utilization after cardiac surgery in children. DESIGN: Prospective, observational, cross-sectional study with factorial design. SETTING: Pediatric ICU at a university hospital. PATIENTS: Twenty-six consecutive children during the first 3 days after open-heart surgery. INTERVENTIONS: Patients were mechanically ventilated and received routine therapeutic interventions. MEASUREMENTS AND MAIN RESULTS: VO2, resting energy expenditure, and substrate utilization were determined by indirect calorimetry. Cardiac index was calculated using the Fick equation from the measured VO2 and the arterial-mixed venous oxygen content difference, and this cardiac index value was compared with a simultaneous cardiac index value that was measured by thermodilution whenever possible. There were excellent correlation and agreement between cardiac index measurements by Fick equation and thermodilution, indicating accurate VO2 measurements. VO2 was consistent with predicted values in healthy resting children. Resting energy expenditure was consistent with the predicted basal metabolic rate. The mean caloric intake was 19% of the mean energy expenditure. The respiratory quotient was 0.74 +/- 0.05. The substrate utilization showed a shift toward fat oxidation and either gluconeogenesis or impaired carbohydrate utilization. CONCLUSIONS: Cardiovascular surgery in children does not significantly alter resting energy expenditure but influences the substrate utilization. Perioperative hormonal stress responses and therapeutically administered catecholamines may explain the shift toward fat oxidation.