HELIUM-OXYGEN IMPROVES CLINICAL ASTHMA SCORES IN CHILDREN WITH ACUTE BRONCHIOLITIS

Objective: To determine the efficacy of a helium oxygen mixture in chi ldren admitted to the pediatric intensive care unit with acute respira tory syncytial virus (RSV) bronchiolitis. Design: Randomized, double-b lind, controlled, crossover study and nonrandomized, prospective study . Setting: A pediatric intensive care unit in a university hospital. P atients: Nonintubated children with signs of acute lower respiratory t ract infection and a positive rapid immunoassay for RSV admitted to th e pediatric intensive care unit. Interventions: Treatment with either helium oxygen or air-oxygen was administered in random order for 20 mi ns. 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 recorde d at baseline (before randomization) and at the end of each 20 min tre atment period (helium oxygen or air-oxy gen). Nonrandomized patients w ere studied 20 mins into helium-oxygen delivery. Eighteen patients wer e studied, 13 of whom were randomized. Five children with severe bronc hiolitis (Clinical Asthma Score of greater than or equal to 6) were in itially given helium oxygen and scored at 20 mins. Mean Clinical Asthm a 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 de creased 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 pos itive correlation (r(s) = .72) was observed between the Clinical Asthm a Score at baseline and the change in Clinical Asthma Score during hel ium oxygen administration (p = .009). Respiratory rate and heart rate decreased during helium oxygen treatment but were not statistically si gnificant. No complications occurred during helium-oxygen delivery. Co nclusions: Inhaled helium oxygen improves the overall respiratory stat us of children with acute RSV lower respiratory tract infection. In pa tients with mild to moderate bronchiolitis (Clinical Asthma Scores of <6), the beneficial effects of helium-oxygen were most pronounced in c hildren with the greatest degree of respiratory compromise.