[The effect of urapidil and sodium nitroprusside on intrapulmonary right-left shunt and arterial oxygenation in the treatment of hypertension following coronary surgery].

20 patients who developed arterial hypertension following coronary artery bypass grafting were randomly treated with either sodium nitroprusside (SNP) or urapidil. Both drugs led to a significant decrease in blood pressure. A significant tachycardia was noted only in the SNP-group. A decrease in peripheral and pulmonary vascular resistance was seen in both groups. Following application of SNP, alveolarterial oxygen difference and venous admixture increased significantly, whereas PaO2 showed a significant decrease. Three patients had to be taken out of the SNP group because of an increase of venous admixture. Alveoloarterial oxygen difference and venous admixture showed no significant changes following application of urapidil.