Background and objective: We set out to compare the efficacy of clevidipine and sodium nitroprusside infusions in the control of blood pressure and the haemodynamic changes they produce in hypertensive patients after operation for elective coronary bypass grafting.
Methods: Thirty patients were randomly allocated to receive either clevidipine or sodium nitroprusside after their mean arterial pressure (MAP) had reached > 90 mmHg for at least 10 min in the postoperative period. The MAP was continuously measured and related to time. Thus, the efficacy of the drugs in controlling arterial pressure could be inversely related to the total area under the MAP-time curve outside a target MAP range of 70-80 mmHg normalized per hour (AUC(MAP) mmHg min h(-1)). Haemodynamic variables and the number of dose-rate adjustments required to maintain MAP were also studied.
Results: There was no statistically significant difference in the efficacy (AUC(MAP) mmHg min h(-1)) of clevidipine (106 +/- 25 mmHg min h(-1)) compared with sodium nitroprusside (101 +/- 28 mmHg min h(-1)). Nor was any significant difference found in the total number of dose adjustments required to control MAP within the target range. The heart rate in patients receiving clevidipine increased less than in those given sodium nitroprusside. Stroke volume, central venous pressure and pulmonary artery pressure were significantly reduced upon administration of sodium nitroprusside but not of clevidipine.
Conclusions: There was no significant difference between clevidipine and sodium nitroprusside in their efficacy in controlling MAP. The haemodynamic changes, including tachycardia, were less pronounced with clevidipine than with sodium nitroprusside.