Effect of intraoperative angiotensin-converting enzyme inhibition by quinaprilat on hypertension after coronary artery surgery

Activation of the renin-angiotensin system during cardiopulmonary bypass (C PB) may be involved in early postoperative hypertension after coronary arte ry bypass grafting (CABG). As hypertensive episodes may be deleterious in t he immediate postoperative period, we have assessed the effects of prophyla ctic treatment with the angiotensin-converting enzyme inhibitor quinaprilat in an open study. During steady state CPB, patients received quinaprilat 0 .02 mg kg(-1) (group A, n=10), quinaprilat 0.04 mg kg(-1) (group B, n=10) o r saline solution (group C, n=10) as an i.v. bolus dose. Sodium nitroprussi de (SNP) was given after operation when systolic arterial pressure was >150 mm Hg. Requirements for SNP 1 h after arrival in the ICU were significantl y less in groups A (two of 10) and B (two of 10) than in group C (eight of 10). Also, patients in group C had a greater systolic arterial pressure com pared with groups A and B. There were no significant differences between gr oups in diastolic arterial pressure, heart rate, cardiac index or cardiac f illing pressures. We conclude that quinaprilat can be used during CABG to r educe the incidence of postoperative hypertension. Further studies of the e fficacy and safety of this technique are necessary.