EMPHYSEMATOUS CHANGES ASSESSED BY SELECTIVE ALVEOLOBRONCHOGRAPHY AND BRONCHODILATOR RESPONSE IN CHRONIC AIR-FLOW OBSTRUCTION

To investigate the relationship between the emphysematous changes and bronchodilator responses in patients with chronic airflow obstruction (CAO), we studied the correlation between bronchodilator response to 1 0 mg inhaled metaproterenol and the extent of emphysema, using selecti ve alveolobronchogram (SAB). Fifty-one patients with CAO were classifi ed into 3 groups by the extent of emphysematous changes detected by SA B. In group 1, no or mild emphysematous change was observed on SAB (n = 9); in group 2, there were significant emphysematous changes but the involved area was less than 75% (n = 17); in group 3, emphysematous c hange was extensive and covered more than 75% (n = 25). The post-bronc hodilator forced expiratory volume in 1 sec (FEV(1)) of patients in gr oup 3 was significantly lower than in groups 1 and 2. The mean value o f changes of FEV(1) as a percentage of predicted FEV(1) of patients in group 3 was significantly lower than in groups 1 and 2. These results indicated that the extent of emphysematous change correlated positive ly with the severity of fixed airflow obstruction, and negatively with the bronchodilator response.