RT Journal Article
SR Electronic
T1 Evaluation of bronchodilator responses in patients with “irreversible” emphysema
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 914
OP 920
DO 10.1183/09031936.01.00216501
VO 18
IS 6
A1 D.E. O'Donnell
A1 L. Forkert
A1 K.A. Webb
YR 2001
UL http://erj.ersjournals.com/content/18/6/914.abstract
AB Given the emerging physiological and clinical rationale for pharmacological lung-volume reduction, assessment of volume responses to bronchodilators is likely to be highly relevant in chronic obstructive pulmonary disease (COPD). The authors examined the magnitude of lung-volume reduction after acute bronchodilator treatment in patients with advanced emphysema. Eighty-four stable patients with emphysema (mean±sem forced expiratory volume in one second (FEV1): 32±1% predicted) performed spirometry and body plethysmography before and 15–30 min after 200 µg salbutamol. Only irreversible patients with a postbronchodilator change in FEV1 <10% pred were considered in this study. Postsalbutamol, the majority of subjects (83%) had significant improvements in one or more lung volumes: on average, residual volume (RV), functional residual capacity (FRC), inspiratory capacity (IC), forced vital capacity and slow vital capacity changed by −18±2, −10±1, 8±1, 9±1 and 7±1% pred (p<0.0005 each). Total lung capacity (TLC) decreased 0.12±0.04 L (p<0.01). Change in IC reflected change in FRC (r=−0.60, p<0.0005), but more strongly in the 57% of patients with no significant change in TLC (r=−0.93, p<0.0005). The magnitude and frequency of volume responses were greatest in patients with the most severe COPD; for example, RV decreased by 0.51±0.09 L (23±4% pred) and 0.27±0.04 L (14±2% pred) in severe and moderate subgroups, respectively. Significant reductions in lung hyperinflation occurred in the absence of a change in forced expiratory volume in one second after low-dose salbutamol in a majority of patients with advanced emphysema; the greatest changes occurred in those with the most severe disease. This work was supported by the Ontario Ministry of Health.