Effect of extending the time after bronchodilator administration on identifying bronchodilator responsiveness in a pediatric pulmonary clinic

Objectives: American Thoracic Society/European Respiratory Society (ATS/ERS) spirometry interpretation guidelines recommend >= 15min between pre- and post-bronchodilator testing to evaluate for a bronchodilator response. We aimed to lengthen the time between albuterol administration and post-bronchodilator testing to adhere to ATS/ERS guidelines and evaluated if lengthening this wait time would increase the percentage of patients classified as bronchodilator responsive. Methods: We compared the proportion of patients with a positive bronchodilator response between two groups of children with asthma, one group in which post-bronchodilator administration wait times were not standardized (pre-intervention) to another in which the wait time was extended to 15min to adhere to ATS/ERS standards (post-intervention). We also determined the effect of this intervention on clinic appointment duration. Results: The analysis included 271 patients (145 pre-intervention and 126 post-intervention). The average wait time in the pre-intervention group was 6.52.1 (mean +/- SD) minutes compared to 16.2 +/- 3.2min (P < 0.001) post intervention, and clinic times increased from 83.0 +/- 29.6min to 91.7 +/- 22.5min (P < 0.007) from the pre- to post-intervention group, respectively. In adjusted regression analysis, there was no significant change in FEV1% predicted between the two groups. Conclusions: In a busy pediatric pulmonary clinic, while we successfully lengthened time between albuterol administration and post-bronchodilator testing in the vast majority of patients, no difference was seen in the percentage of patients classified as bronchodilator responsive. Results from this study appear to question the ATS/ERS recommended 15min post-bronchodilator administration wait time for children.