Low intraoperative Bispectral Index (BIS) values may be associated with increased mortality. In a previously reported trial to prevent delirium, we randomized patients undergoing hip fracture repair under spinal anesthesia to light (BIS >80) or deep (BIS approximately 50) sedation. We analyzed survival of patients in the original trial. Among all patients, mortality was equivalent across sedation groups. However, among patients with serious comorbidities (Charlson score >4), 1-year mortality was reduced in the light (22.2%) vs deep (43.6%) sedation group (hazard ratio [HR], 0.43; 95% confidence interval, 0.19–0.97; P = 0.04) during spinal anesthesia. Similarly, among patients with Charlson score >6, 1-year mortality was reduced in the light (28.6%) vs deep (52.6%) sedation group (HR 0.33; 95% confidence interval, 0.12–0.94; P = 0.04) during spinal anesthesia. Further research on reduced mortality after light sedation during spinal anesthesia is needed.
From the *Department of Anesthesiology and Critical Care Medicine, Johns Hopkins Medical Institutions; and †Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.
Accepted for publication November 27, 2013.
Funding: 1 R01 AG033615-01A1 NIH KL-2 Clinical Research Scholars Program RO3 AG042331 Jahnigen Career Development Award.
The authors declare no conflicts of interest.
This report was previously presented, in part, at the Translational Science Meeting.
Reprints will not be available from the authors.
Address correspondence to Charles H. Brown IV, MD MHS, Department of Anesthesiology and Critical Care Medicine, Johns Hopkins Medical Institutions, Zayed 6208, 1800 Orleans St., Baltimore, MD 21287. Address e-mail to firstname.lastname@example.org.