beta-agonists through metered-dose inhaler with valved holding chamber versus nebulizer for acute exacerbation of wheezing or asthma in children under 5 years of age: a systematic review with meta-analysis.

OBJECTIVE: To compare the efficacy of beta-agonists given by metered-dose inhaler with a valved holding chamber (MDI+VHC) or nebulizer in children under 5 years of age with acute exacerbations of wheezing or asthma in the emergency department setting. STUDY
DESIGN: Published (1966 to 2003) randomized, prospective, controlled trials were retrieved through several different databases. The primary outcome measure was hospital admission.
RESULTS: Six trials (n=491) met criteria for inclusion. Patients who received beta-agonists by MDI+VHC showed a significant decrease in the admission rate compared with those by nebulizer (OR, 0.42; 95% CI, 0.24-0.72; P=.002); this decrease was even more significant among children with moderate to severe exacerbations (OR, 0.27; 95% CI, 0.13-0.54; P=.0003). Finally, measure of severity (eg, clinical score) significantly improved in the group who received beta-agonists by MDI+VHC in comparison to those who received nebulizer treatment (standardized mean difference, -0.44; 95% CI, -0.68 to -0.20; P=.0003).
CONCLUSIONS: The use of an MDI+VHC was more effective in terms of decreasing hospitalization and improving clinical score than the use of a nebulizer in the delivery of beta-agonists to children under 5 years of age with moderate to severe acute exacerbations of wheezing or asthma.