Fairshter R D, Wilson A F
Am Rev Respir Dis. 1980 Jul;122(1):27-32. doi: 10.1164/arrd.1980.122.1.27.
In an effort to determine the relationship between the major sites of airflow limitation and bronchodilator action, physiologic studies were performed in 65 asthmatics before and after the administration of isoproterenol, metaproterenol, or terbutaline. Before the administration of a bronchodilator, the results of routine pulmonary function tests were abnormal; the mean increment in maximal expiratory flow at 50% of forced vital capacity (delta VEmax50) after breathing 80% helium-20% oxygen (He-O2) was reduced (p < 0.001). Prebronchodilator values of delta VEmax50 correlated linearly with VEmax50 breathing air (r = + 0.68, p < 0.001). These data suggested that airflow limitation becomes more peripheral as asthma becomes more severe. After the bronchodilator administration, the results of routine pulmonary function studies improved; delta VEmax50 either increased or decreased, depending upon the prebronchodilator values. Density-dependence tended to (1) increase in subjects with low prebronchodilator values of delta VEmax50, and (2) decrease in subjects with high prebronchodilator values of delta VEmax50. Hence, these results suggested that predominant sites of bronchodilatation in asthmatics are related to the prebronchodilator sites of airflow limitation.
为了确定气流受限的主要部位与支气管扩张剂作用之间的关系，对65例哮喘患者在给予异丙肾上腺素、间羟异丙肾上腺素或特布他林之前和之后进行了生理学研究。在给予支气管扩张剂之前，常规肺功能测试结果异常；吸入80%氦气-20%氧气（He-O2）后，用力肺活量50%时的最大呼气流量平均增加值（δVEmax50）降低（p<0.001）。支气管扩张剂使用前的δVEmax50值与吸入空气时的VEmax50呈线性相关（r=+0.68，p<0.001）。这些数据表明，随着哮喘病情加重，气流受限变得更加外周化。给予支气管扩张剂后，常规肺功能研究结果有所改善；δVEmax50要么增加，要么降低，这取决于支气管扩张剂使用前的值。密度依赖性倾向于：（1）在支气管扩张剂使用前δVEmax50值较低的受试者中增加，（2）在支气管扩张剂使用前δVEmax50值较高的受试者中降低。因此，这些结果表明，哮喘患者支气管扩张的主要部位与气流受限的支气管扩张剂使用前部位有关。
