THE EFFECT OF IV ENALAPRILAT IN CHRONICALLY TREATED HYPERTENSIVE PATIENTS DURING CARDIAC-SURGERY

Background: Angiotensin-converting enzyme (ACE) inhibitors are well es tablished as long-term antihypertensives and have also been proved use ful in hypertensive emergencies. Therefore, we investigated whether in traoperative i.v. enalaprilat may reduce the incidence of perioperativ e hypertensive reactions in coronary artery bypass grafting (CABG). Me thods: Thirty-eight male patients chronically treated for arterial hyp ertension and scheduled for CABG randomly and double-blindly received either enalaprilat 30 mu g.kg(-1) or NaCl 0.9% at the time of skin inc ision. Intraoperatively, increases of mean arterial pressure (MAP) >85 mmHg or >80 mmHg during cardiopulmonary bypass (CPB) were treated by an urapidil bolus. The total intraoperative amount of urapidil was doc umented for both groups. Systemic and pulmonary hemodynamics as well a s the plasma levels of epinephrine, norepinephrine, arginine vasopress in and renin were measured intraoperatively and up to 2 h after admiss ion to the intensive care unit. Results: Mean arterial pressure, cardi ac index and systemic vaslcular resistance did not differ between the enalaprilat and the control group. Renin plasma levels significantly i ncreased after infusion of enalaprilat and did not change in the place bo group. Catecholamine and arginine vasopressin plasma levels increas ed significantly during CPB and remained high in the postoperative per iod without any intergroup difference. The same amount of urapidil had to be given in the two groups to maintain MAP below the defined limit . Conclusion: We conclude that infusing 30 mu g.kg(-1) enalaprilat in patients chronically treated for arterial hypertension does not preven t hypertensive reactions during CABG.