Assessment of a new device (aerochamber) for use with aerosol drugs in asthmatic children.

We compared the pulmonary response to fenoterol delivered by a conventional MDI with the response after MDI plus the aerochamber (AC). Twelve children with moderate to severe asthma (mean age 10.8 years) participated in this double-blind crossover study. On two consecutive days, in random order, subjects received one puff of fenoterol hydrobromide (200 mcg) either by MDI or MDI plus AC. Pulmonary function, cardiovascular response and tremor were assessed over a period of four hours. In a similar fashion, the children received one puff of fenoterol three times a day for six weeks by either method in a randomized open study. Daily symptoms and peak flows before and after drug were recorded in daily diaries. The patients returned to the pulmonary function laboratory at 6 and 12 weeks for four hour pulmonary function tests. In the short-term study, the magnitude and time course of pulmonary response was similar for both treatment regimens (p greater than 0.4). No significant effects on blood pressure or pulse or differences in tremor assessment were seen. Similarly, in the long term study the baseline pulmonary function and pulmonary response were markedly consistent between the two treatment regimens (p greater than 0.05). Peak flows were significantly higher in the evening than in the morning (p less than 0.001) and the magnitude of the response to drug was higher in the morning than the evening (p less than 0.001). There were no differences between MDI and MDI plus AC in daily symptom scores or use of concomitant medication. We conclude that acute or chronic administration of fenoterol aerosol to asthmatic children by MDI with or without the AC produces similar benefits in pulmonary function, symptomatology and concomitant medication. The AC device would be a useful adjunct for a child who has difficulty in coordinating the metered dose inhaler.