A comparison of fenoldopam and nitroprusside in the control of hypertension following coronary artery surgery

A prospective trial to compare the effects of the synthetic dopaminergic (DA 1) agonist, fenoldopam (FEN), with sodium nitroprusside (SNP) for control of blood pressure following coronary artery bypass graft surgery was carried out in 20 patients. Patients were randomly allocated to receive either FEN or SNP when the systolic arterial blood pressure (SAP) rose above 130 mmHg. The goal of therapy was to achieve a stable control of blood pressure below 130 mmHg at a level at least 25 mmHg below the pretreatment value. Treatment was then continued for 2 hours. Hemodynamic measurements were made before treatment, after stable control of blood pressure had been achieved, and thereafter at 30, 60, and 120 minutes. Urine output, sodium, potassium, and creatinine clearance were also measured during the study. Both SNP and FEN caused a rapid and significant fall in SAP ( P < 0.001) and a fall in systemic vascular resistance ( P < 0.001). FEN caused an increase in cardiac index ( P < 0.001) and in stroke volume ( P < 0.001) in contrast to SNP. Urine output and potassium clearance fell with SNP ( P < 0.05) in contrast to FEN. Thus, FEN would appear to control SAP as effectively as SNP, but may have more beneficial effects on cardiac output and some aspects of renal function.