To evaluate the effect of bronchodilator inhalation on the diffusion capacity in patients with COPD.
58 COPD patients were tested with bronchodilator inhalation (Albuterol 200ug) and divided into 2 groups according to the response of FEV1 : Positive if FEV1 increase ≥15% and >200ml, Negative if FEV1 increase <15% and <200ml. The transfer factor of the lung for carbon monoxide (TLco), pulmonary membrane diffusion capacity (Dm) and pulmonary capillary blood volume (Vc) were measured in baseline and after Albuterol inhalation and compared subsequently in each group.
40 COPD patients were found positive and 18 were negative in the Albuterol inhalation test. No significant differences were found in Dm, TLco and Vc between baseline and after Albuterol inhalation in either group.
Bronchodilator inhalation did not affect diffusion capacity in COPD patients.
Bronchodilator inhalation improves symptoms of COPD patients mainly by way of the improvement of ventilation rather than the improvement of diffusion capacity.
BronchodilatorinhalationNDmml/min/mm HgTLco%PredVcmlPositive group Baseline409.87±4.7167.49±19.4750.08±20.82 After11.10±5.3467.87±20.0250.71±24.32Negative group Baseline188.05±4.3461.99±21.1047.46±18.18 After187.47±3.7758.62±18.2553.10±25.41
Yaling Zhu, None.