Table. 8—

Selected studies of bronchodilator response

PopulationAgent/mode of deliveryFVCFEV1MEF25–75% or MEF50%Comments
Selected population studies
 1063 subjects 8–75 yrs of age; general population 108IP 2 puffs via MDI10.7% (0.40 L)7.7% (0.31 L)20%95th percentile for per cent change from baseline
 2609 subjects; random sample of 3 areas in Alberta, Canada 109TB 500 µg via spacerMales 9% (0.34 L); females 9% (0.22 L)95th percentile for per cent change from baseline in asymptomatic never-smokers with FEV1 >80% pred
 75 selected normal subjects 110Two puffs via MDI5.1% (0.23 L)10.1% (0.36 L)48.3%Upper 95% CL (two-tailed) for per cent change from baseline
Selected patient studies
 40 patients referred to PFT laboratory 112Placebo14.9% (0.34 L)12.3% (0.18 L)45.1%Upper 95% CI change after placebo
 985 COPD patients in the IPPB trial 111IP 250 µg via air nebuliser15%Per cent change from baseline
 150 patients with airway obstruction 113SB 200 µg or TB 500 µg via MDI15% (0.33 L)10% (0.16 L)95% CI for absolute change
 78 patients with COPD/asthma 101SB 200 µg via MDI14% (0.51 L)15% (0.25 L)95% CL per cent change of baseline
  • FVC: forced vital capacity; FEV1: forced expiratory volume in one second; MEF25–75%: mean flow between 25% and 75% of FVC; MEF50%: flow at 50% of FVC; IP: isoproterenol; MDI: metered dose inhaler; TB: terbutaline; % pred: % predicted; SB: salbutamol; CL: confidence limits; PFT:pulmonary function tests; CI: confidence interval; COPD: chronic obstructive pulmonary disease; IPPB: intermittent positive pressure breathing; Other variables as in table 6.