Hemodynamic effects of vasodilators on pulmonary hypertension in decompensated chronic obstructive pulmonary disease.

Vasodilators have been reported to improve the hemodynamic status of some patients with pulmonary hypertension secondary to chronic obstructive pulmonary disease (COPD). We investigated the effects of sodium nitroprusside (50 micrograms/min) and hydralazine (25 mg) on pulmonary hemodynamics in 12 patients during acute exacerbation of COPD. Apart from its known systemic effects, nitroprusside decreased significantly mean pulmonary artery pressure (MPAP) from 36 +/- 10 to 31 +/- 12 mm Hg (p less than .04), decreased slightly pulmonary vascular resistance, and did not change cardiac index. Except for a slight but significant increase in MPAP from 35 +/- 5 to 38 +/- 5 mm Hg (p less than .002), hydralazine produced no significant hemodynamic changes. These results suggest that vasodilator therapy with sodium nitroprusside and hydralazine for pulmonary hypertension secondary to acute COPD is probably not helpful.