[Effects of inhaled beta-adrenergic and anticholinergic drugs on respiratory function and arterial blood gases in patients with pulmonary emphysema].

We studied the effects of inhaled anticholinergic (oxitropium bromide, 0.2 mg) and beta-adrenergic (fenoterol 0.4 mg) drugs on respiratory function and arterial blood gases in fourteen male patients with pulmonary emphysema (age 63 +/- 8 years; FEV1/FVC 1.41 +/- 0.73 L) using a three day, randomized, double-blind placebo-controlled design. Each day, spirometry and arterial blood gas analyses were performed before and 45 min after inhalation. Both fenoterol and oxitropium bromide significantly improved FEV1 by 21% and 16%, respectively, although there was no significant difference between the two drugs. However, the mean value of PaO2 significantly decreased from 74.5 +/- 2.6 to 69.3 +/- 2.7 Torr with fenoterol, but not with oxitropium and placebo. Change of PaO2 with fenoterol was significantly correlated with %FRC, but not with FEV1 nor change of FEV1. We therefore conclude that an anticholinergic inhalant bronchodilator is more favorable for patients with COPD than a beta-adrenergic agent.