Objective To compare the differences of flow and volume responses in patients with mild to very severe chronic obstructive pulmonary disease（COPD） in bronchodilatation test. Methods The different changes of FEV1 and FVC in 217 patients with mild to very severe COPD（GOLD stage Ⅱ-Ⅳ） after inhaling salbutamol were analyzed retrospectively. Results FEV1 and FVC of the patients with COPD at stage Ⅱ-Ⅳ increased remarkably after inhaling β2 agonist，while there were significant differences between the changes of FEV1 and FVC. Increment of FEV1 and FVC (ΔFEV1 and ΔFVC)，representing flow and volume responses respectively，showed a normal distribution. The majority of patients fell in the range of ΔFEV1 from 0.00 to 0.04，0.05 to 0.09 and 0.10 to 0.14 liter，and ΔFVC from 0.00 to 0.09，0.10 to 0.19 and 0.20 to 0.29 liter. There was significant difference of ΔFEV1 among stage Ⅱ-Ⅳ patients with COPD （P lt;0.01），namely more severe the disease less ΔFEV1 got.In the other hand ΔFVC increased along with the progression of COPD，although no significant difference of ΔFVC among stage Ⅱ-Ⅳ patients with COPD was found. Though different changes of ΔFEV1 and ΔFVC were revealed，there was a positive correlation between ΔFEV1 and ΔFVC in patients at each GOLD stage and the correlation became more insignificant with the progression of COPD. Conclusions There are significant differences between post-bronchodilator flow and volume responses in patients with COPD.Flow response decreases remarkably along with the progression of COPD，whereas volume response increases along with the progression of COPD.
Citation： JIANG Han,ZHANG Qiao,LIN Kexiong,ZHAO Zhiqiang,WANG Jinping,WANG Changzheng. Differences of Flow and Volume Responses after Inhalation of Bronchodilator in Patients with Mild to Very Severe COPD. Chinese Journal of Respiratory and Critical Care Medicine, 2009, 09(2): 110-113. doi: Copy