RISKS OF GENERAL-ANESTHESIA AND ELECTIVE OPERATION IN THE HYPERTENSIVE PATIENT

To determine the risks of general anesthesia and elective surgical procedures in patients who have histories of hypertension, the authors prospectively studied 676 consecutive operations in a series of patients more than 40 years old. All patients were examined preoperatively, monitored intraoperatively, and closely followed postoperatively. Although patients with higher preoperative blood pressure values had larger absolute intraoperative blood pressure decreases, the mean intraoperative systolic pressure nadirs in patients with tightly-controlled hypertension (100 ± 2 torr) did not differ from those in patients with persistent treated (97 ± 3 torr) or untreated (98 ± 2 torr) mild to moderate hypertension. Similarly, among these three groups of patients, the needs for intraoperative adrenergic agents or fluid challenges (20, 33, and 27%, respectively) and the incidences of perioperative hypertensive events (27, 25, and 20%, respectively) were not significantly different. Multivariate analysis of data for the patients with histories of hypertension showed that neither the preoperative in-hospital diastolic nor preoperative in-hospital systolic blood pressure values independently correlated with any of these three indices of perioperative blood pressure lability, with the development of cardiac arrhythmias, ischemia, or failure, or with postoperative renal failure. Effective intraoperative management may be more important than preoperative hypertensive control in terms of decreasing clinically significant blood pressure lability and cardiovascular complications in patients who have mild to moderate hypertension.