Effects of Inhalaed Beta-Adrenergic and Anticholinergic Drugs on Respiratory Function and Arterial Blood Gases in Patients with Pulmonary Emphysema

Abstract

We studied the effects of inhaled anticholinergic (oxitropium bromide, 0.2mg) and beta-adrenergic (fenoterol 0.4mg) drugs on respiratory function and arterial blood gases in fourteen male patients with pulmonary emphysema (age 63±8 years; FEV₁/FVC1.41±0.73L) using a three day, randomized, double-blind placebocontrolled design. Each day, spirometry and arterial blood gas analyses were performed before and 45min 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±2.7Torr 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.