Clinical question: Are beta-2 agonists as effective when administered through a holding chamber (spacer) as they are when administered by a nebulizer?
Background: During an acute asthma attack, beta-2 agonists must be delivered to the peripheral airways. There has been considerable controversy regarding the use of a spacer compared with a nebulizer. Aside from admission rates and length of stay, factors taken into account include cost, maintenance of nebulizer machines, and infection control (potential of cross-infection via nebulizers).
Study design: Meta-analysis review of randomized controlled trials (RCTs).
Setting: Multi-centered, worldwide studies from community setting and EDs.
Synopsis: In 39 studies of patients with an acute asthma attack (selected from Cochrane Airways Group Specialized Register), the hospital admission rates did not differ on the basis of delivery method in 729 adults (risk ratio=0.94, confidence interval 0.61-1.43) or in 1,897 children (risk ratio=0.71, confidence interval 0.47-1.08). Secondary outcomes included the duration of time in the ED and the duration of hospital admission. Time spent in the ED varied for adults but was shorter for children with spacers (based on three studies). Duration of hospital admission also did not differ when modes of delivery were compared.
Bottom line: Providing beta-2 agonists using nebulizers during an acute asthma attack is not more effective than administration using a spacer.
Citation: Cates CJ, Welsh EJ, Rowe BH. Holding chambers (spacers) versus nebulisers for beta-agonist treatment of acute asthma. Cochrane Database Syst Rev. 2013;9:CD000052.