To the Editor.—
During a study of the effects of nitroprusside-induced hypotension on surgical bleeding, we incidentally noticed the frequent occurrence of postoperative adynamic ileus in patients whose mean arterial systolic blood pressure (BP) was maintained at the 50- to 65-mm Hg range intraoperatively.
Fifty consecutive patients scheduled for elective total hip replacement were divided into three groups according to their medical condition. Group 1 consisted of 26 healthy patients (American Standards Association physical status, 1 or 2) with no clinical evidence of cerebrovascular disease and with a resting diastolic BP of less than 100 mm Hg. Group 2 included 12 patients with known hypertension and a resting diastolic pressure of greater than 100 mm Hg but with no clinical evidence of cerebrovascular and/or renal disease (ASA physical status 2 or 3). Group 3 included 12 patients, all of whom were ASA physical status 3 or higher, who had