Comparison of two chamber devices in patients using a metered-dose inhaler with satisfactory technique.

A randomized clinical crossover trial was carried out to compare the use in the home, during 1-week periods, of two commercially available chamber devices (the Aerochamber and the Spacer) and a standard metered-dose inhaler (MDI) in 24 patients with reversible bronchospasm and satisfactory inhaler technique. Measurements of peak flow, forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), ratio of FEV1 to FVC and forced midexpiratory flow rate were made immediately before and 15 minutes after inhalation of terbutaline sulfate. No difference was noted in results of spirometry, peak flow readings or side effects between the devices. The results of spirometry were better during the trial than immediately before it (p less than 0.01). The mean score for inhaler technique was significantly lower at follow-up than during the trial (p less than 0.001). The results suggest that in this population there is no advantage to using either a chamber device rather than an MDI or one chamber device rather than the other.