Efficacy of bronchodilator therapy in bronchiolitis. A meta-analysis.

OBJECTIVE To determine if bronchodilators are efficacious in treating bronchiolitis. DATA SOURCES A search of bibliographic databases (MEDLINE, Excerpta Medica, and Reference Update) for bronchiolitis and albuterol or ipratropium bromide, or adrenergic agents or bronchodilator agents. Reference lists were also used. STUDY SELECTION Randomized, placebo-controlled trials of bronchodilator treatment in bronchiolitis were selected by 2 investigators. Fifteen of 89 identified publications met the selection criteria. DATA EXTRACTION Investigators independently abstracted data for 3 outcomes: clinical score, oxygen saturation, and hospitalization. Clinical score was measured as a dichotomous variable (score +/- improved) or continuous variable (average score). DATA SYNTHESIS For primary analysis, data were pooled from 8 trials of children with first-time wheezing. The effect size for average score was -0.32 (95% confidence interval [CI], -0.54 to -0.11; P < .01), favoring treatment; the relative risk for score +/- improved was 0.76 (95% CI, 0.60 to 0.95; P = .02), favoring treatment. Bronchodilators had no effect on hospitalization (relative risk, 0.85; 95% CI, 0.47 to 1.53; P = .58), but co-interventions may have been administered prior to this outcome. The results for oxygen saturation were too varied to allow pooling of the results. Secondary analyses were performed on 4 outpatient trials of children with first-time wheezing, 7 trials in which only nebulized beta-agonists were used, and on all 15 trials identified. The results were similar, but the data varied more. CONCLUSION Bronchodilators produce modest short-term improvement in clinical features of mild or moderately severe bronchiolitis.