Tuberc Respir Dis.  1987 Jun;34(2):144-149. 10.4046/trd.1987.34.2.144.

Site of Airway Obstruction and Localization of Bronchodilator Response in Asthma

• KMID: 2528658
• DOI: http://doi.org/10.4046/trd.1987.34.2.144

Abstract

ln order to determine the relationship between the major sites of airflow limitation and bronchodi1ator action. we studied helium response before and after the administration of bronchodi1ator in 23 asthmatics. Our results were as follows; 1) ln the 23 asthmatics. there were 16 responders and 7 nonresponders. 2) After bronchodi1ator. 13 responders remained responders and 4 nonresponders became responders. 3) A highly significant correlation was noted between prebronchodilator values of FEF 50% (air) and FEF 50% (He-O₂). 4) A significant inverse correlation was present between prebronchodilator values of ΔFEF 50% and the incremental or decremental changes in ΔFEF 50% postbronchodilator [Δ(Δ FEF 50%)]. This study suggests that the patients with severe degree of obstruction in asthma tend to have airflow limitation in the peripheral airways and the predominant sites of bronchodi1atation in asthmatics are related to the prebronchodi1ator obstructive sites.