Comparative effects of acute O2 breathing and terbutaline in patients with chronic obstructive pulmonary disease. A combined hemodynamic and radionuclide study.

The acute effects of terbutaline (T) and breathing 100% O2 (O2) on gas exchange, pulmonary hemodynamics and radionuclide angiography were evaluated in 15 patients with severe chronic obstructive pulmonary disease (COPD). O2 breathing resulted in a decrease in mean pulmonary artery pressure (PAP) and cardiac index (CI) without changing pulmonary vascular resistance index (PVRI) or right and left ventricular ejection fractions (RVEF, LVEF). On the other hand, T administration was followed by a decrease in PVRI, an increase in CI, RVEF and LVEF. These effects of T were maintained during exercise. Although RVEF was inversely correlated with basal levels of PAP or PVRI, acute changes in pulmonary hemodynamics were not correlated with significant changes in RVEF. These results suggest that T may be useful in the treatment of patients with COPD prone to develop cor pulmonale. However, the long-term benefit of this treatment remains to be established.