TREATMENT OF POSTOPERATIVE HYPERTENSION AFTER CORONARY-ARTERY BYPASS-SURGERY - DOUBLE-BLIND COMPARISON OF INTRAVENOUS ISRADIPINE AND SODIUM-NITROPRUSSIDE

Background Hypertension commonly occurs after cardiac surgery and requ ires therapy to prevent the potentially deleterious effects. Methods a nd Results After coronary artery bypass graft surgery (CABG), 177 pati ents with elevated blood pressure greater than or equal to 90 mm Hg du ring the initial 6-hour postsurgical period were selected for this ran dom blinded, parallel study to receive intravenous infusions of either isradipine (n=90) or sodium nitroprusside (n=87). Isradipine produced a statistically significant decrease in mean arterial pressure (MAP, Delta-23 mm Hg) during a 90-minute treatment period. Target MAP (less than or equal to 85 mm Hg or a decrease of 10 mm Hg, if baseline MAP w as between 90 and 95 mm Hg) was achieved in 94% of patients 30 minutes after initiation of isradipine infusion (total mean dose, 411 mu g); target MAP was achieved in 75% of nitroprusside-treated patients (tota l mean dose, 1708 mu g). The mean time to control MAP was 18 minutes f or isradipine compared with 24 minutes for nitroprusside. Global smoot hness in MAP control was graded on a scale of 0 (not controlled) to 5 (excellent). Approximately 76% of isradipine-treated patients received a rating of greater than or equal to 3 (mean score, 3.5); 40% of the sodium nitroprusside-treated patients achieved a score of greater than or equal to 3 (mean score, 2.0). Both isradipine and nitroprusside pr oduced statistically significant reductions in systolic and diastolic blood pressures, a decrease in systemic vascular resistance, and incre ases in heart rate, cardiac index, and stroke volume index. Isradipine produced no significant decreases in pulmonary artery occlusion wedge pressure compared with nitroprusside. Conclusions Intravenous isradip ine was effective and well tolerated in patients with hypertension aft er CABG and offers an additional therapeutic option to treat patients after cardiac surgery.