To determine the efficacy of a helium-oxygen mixture in children admitted to the pediatric intensive care unit with acute respiratory syncytial virus (RSV) bronchiolitis.
Randomized, double-blind, controlled, crossover study and nonrandomized, prospective study.
A pediatric intensive care unit in a university hospital.
Nonintubated children with signs of acute lower respiratory tract infection and a positive rapid immunoassay for RSV admitted to the pediatric intensive care unit.
Treatment with either helium-oxygen or air-oxygen was administered in random order for 20 mins. Nonrandomized patients received helium-oxygen as initial therapy.
Measurements and Main Results
Clinical Asthma Score, respiratory rate, heart rate, and pulse oximetry oxygen saturation values were recorded at baseline (before randomization) and at the end of each 20-min treatment period (helium-oxygen or air-oxygen). Nonrandomized patients were studied 20 mins into helium-oxygen delivery. Eighteen patients were studied, 13 of whom were randomized. Five children with severe bronchiolitis (Clinical Asthma Score of >or=to6) were initially given helium-oxygen and scored at 20 mins. Mean Clinical Asthma Score was 3.04 (range 1 to 7.5) in the 13 randomized patients and 4.25 (range 1 to 9) in the 18 patients overall. Clinical Asthma Score decreased in the 13 randomized patients (mean 0.46, p < .05) and in the 18 patients overall (mean 1.23, p < .01) during helium-oxygen delivery. In randomized patients with Clinical Asthma Scores of <6 (n = 12), a positive correlation (rs = .72) was observed between the Clinical Asthma Score at baseline and the change in Clinical Asthma Score during helium-oxygen administration (p = .009). Respiratory rate and heart rate decreased during helium-oxygen treatment but were not statistically significant. No complications occurred during helium-oxygen delivery.
Inhaled helium-oxygen improves the overall respiratory status of children with acute RSV lower respiratory tract infection. In patients with mild-to-moderate bronchiolitis (Clinical Asthma Scores of <6), the beneficial effects of hellum-oxygen were most pronounced in children with the greatest degree of respiratory compromise. (Crit Care Med 1998; 26:1731-1736)