Use of peak expiratory flow for assessing bronchodilator responsiveness

Abstract

Lung function in 1686 adult patients was measured before, and 15 minutes after, salbutamol inhalation. Bronchodilator responsiveness (BDR) was defined as a 12% improvement over baseline in either FEV1 or FVC, along with an absolute volume increment of 200ml. Peak expiratory flow (PEF) change, both absolute and relative to baseline, was also calculated (ΔPEF and ΔPEF%, respectively). Change in PEF significantly correlated with change in FEV1. However, ΔPEF and ΔPEF% had poor discrimination in identifying BDR, with all specific cut-off values for ΔPEF and ΔPEF% having low or moderate sensitivity, specificity and predictive values. © 2009 General Practice Airways Group. All rights reserved.