Twenty patients, American Society of Anesthesiologists class I or II, who developed intraoperative
hypertension (mean arterial pressure greater than 110 mm Hg) during abdominal surgery under balanced
general anesthesia were randomly assigned to two groups. The
nicardipine group (n = 10) received 5 mg of
nicardipine hydrochloride, and the placebo group (n = 10) received 5 mL of
nicardipine solvent injected intravenously over a 5-minute period in a blind manner. Arterial pressure was recorded for 15 minutes after the injection was started. If the mean arterial pressure did not decrease at least 10% at 15 minutes, the trial was opened and patients received 5 mg of
nicardipine. None of the patients in the
nicardipine group received
nicardipine in an open manner, in contrast with 7 of the 10 patients in the placebo group (P less than 0.03, Fisher exact test). During both the blind period and the open trial,
nicardipine induced a 34% decrease in systolic, diastolic, and mean arterial pressure. Minimal values of pressure were noted at 6 minutes; however, arterial pressure remained below the pre-
nicardipine injection values and near preoperative values for 45 minutes. No severe
hypotension was observed, but the
nicardipine injection was stopped at 3 mg in two cases during the blind period because of the rate of pressure reduction. Heart rate remained unchanged during the decrease in arterial pressure in both groups. This study indicates that
nicardipine is an effective, long lasting, and safe therapy for intraoperative
hypertension during abdominal surgery.