Randomized trial of hypotensive epidural anesthesia in older adults.

Background: Data are sparse on the incidence of postoperative cognitive, cardiac, and renal complications after deliberate hypotensive anesthesia in elderly patients.

Methods: This randomized, controlled clinical trial included 235 older adults with comorbid medical illnesses undergoing elective primary total hip replacement with epidural anesthesia. The patients were randomly assigned to one of two levels of intraoperative mean arterial blood pressure management: either to a markedly hypotensive mean arterial blood pressure range of 45-55 mmHg or to a less hypotensive range of 55-70 mmHg. Cognitive outcome was assessed by within-patient change on 10 neuropsychologic tests assessing memory, psychomotor, and language skills from before surgery to 1 week and 4 months after surgery. Prospective standardized surveillance was performed for cardiovascular and renal outcomes, delirium, thromboembolism, and blood loss and replacement.

Results: The two groups were similar at baseline in terms of age (mean, 72 yr), sex (50% women), comorbid conditions, and cognitive function. After operation, no significant differences in the incidence of early or long-term cognitive dysfunction were observed between the two blood pressure management groups. There were no significant differences in the rates of other adverse consequences, including cardiac, renal, and thromboembolic complications. In addition, no differences occurred in the duration of surgery, intraoperative estimated blood loss, or transfusion rates.

Conclusions: Elderly patients can safely receive controlled hypotensive epidural anesthesia with this protocol. There was no evidence of greater risks, or early benefits, with the use of the more markedly hypotensive range.