Two vs four puffs of albuterol: does dose change bronchodilator response?

Abstract

Background

Reversible obstruction on spirometry may be used to diagnose asthma. As per 2005 American Thoracic Society (ATS) guidelines, our pulmonary center began using 360 µg (four puffs) of albuterol rather than 180 µg (two puffs) to determine reversibility on spirometry starting in 2009.

Hypothesis

We hypothesized that fewer patients would respond to two puffs of albuterol than four puffs during spirometric testing.

Methods

We retrospectively reviewed records from new asthmatics seen in Pediatric Pulmonary Clinic from March 2002 to April 2014 who performed reproducible spirometry. Patients were divided into two groups based on whether they had received two or four puffs of albuterol for bronchodilator assessment. A positive bronchodilator response was defined as an increase of ≥12% in forced expiratory volume in one second (FEV₁) or ≥25% in forced expiratory flow (FEF_25–75%). Data were expressed as percentages and mean ± standard error of the mean values. Chi-squared test and Student’s t-test were utilized.

Results

Data were collected for 240 patients; 115 patients received two puffs of albuterol and 125 patients received four puffs. There were no significant differences in baseline characteristics between the two groups. There were no differences following two puffs or four puffs in changes in FEV₁ (10.0±1.1% vs 10.5±1.1% predicted) or FEF_25–75% (30.2±2.9% vs 33.5±2.9% predicted). Moreover, there was no difference in ATS-defined bronchodilator response between the two groups.

Conclusion

Based on the mean change in FEV₁ and overall bronchodilator responsiveness, two puffs of albuterol were not inferior to four puffs in the determination of bronchodilator responsiveness in our pediatric asthmatic patients.

Keywords:

• asthma
• reversible obstructive lung disease
• pulmonary function testing

Acknowledgments

Preliminary results of this study were presented as a poster at the 2013 American Thoracic Society Conference in Philadelphia, Pennsylvania, PA, USA, on May 20, 2013.

Disclosure

The authors report no conflicts of interest in this work.