A pilot study for a prospective, randomized, double-blind trial of the influence of anesthetic depth on long-term outcome

Abstract

BACKGROUND: Deep general anesthesia has been associated with increased mortality in 5 observational studies. The association may be causal or an epiphenomenon due to increased anesthetic sensitivity in high-risk patients. We conducted a pilot study to assess the feasibility of performing a definitive randomized controlled trial. The aims of the study were to determine whether anesthetic depth targeting in a high-risk group was feasible and to document anesthetic doses and arterial blood pressures associated with "deep" and "light" general anesthesia. METHODS: ASA physical status III and IV patients, aged ≥60 years, having surgery lasting ≥2 hours, with expected hospital stay ≥2 days, and rec..