Nicolas Mahr1, Yannis Bouhake1, Gilles Chopard2, Ngai Liu3,4, Nathalie Boichut1, Thierry Chazot3,4, Melanie Claveau1, Lucie Vettoretti1, Gregory Tio5, Sebastien Pili-Floury1,6,7, Emmanuel Samain1,6,7, Guillaume Besch1,6. 1. From the Department of Anesthesiology and Intensive Care Medicine, University Hospital of Besancon, Besancon, France. 2. Department of Neurology, University Hospital of Besancon, and EA 481 Neuroscience, IFR 133, University of Bourgogne Franche-Comte, Besancon, France. 3. Department of Anesthesiology, Foch Hospital, Suresnes, France. 4. Outcomes Research Consortium, Cleveland Clinic, Cleveland, Ohio. 5. Department of Clinical Psychiatry, and Clinical Investigation Center, INSERM CIT 808, University Hospital of Besancon, Besancon, France. 6. EA 3920 INSERM, University of Franche-Comte, Besancon, France. 7. SFRFED 4234 INSERM, University of Franche-Comte, Besancon, France.
Abstract
BACKGROUND: The aim of the study was to investigate whether closed-loop compared to manual bispectral index (BIS)-guided target-controlled infusion of propofol and remifentanil could decrease the incidence of postoperative neurocognitive disordersafter elective major noncardiac surgery. METHODS:Patients aged >50 admitted for elective major noncardiac surgery were included in a single-blind randomized (ratio 2:1) trial. The anesthetic protocol was allocated by randomization into either closed-loop or manual BIS-guided propofol and remifentanil titration. The BIS target range was 40-60. All patients had cognitive assessment the day before surgery and within 72 hours after surgery using a battery of neuropsychological tests. The primary outcome was the rate of postoperative neurocognitive disorders. Postoperative neurocognitive disorders were defined as a decrease >20% from baseline on at least 3 scores. Intergroup comparison of the primary outcome was performed using the χ test. RESULTS:A total of 143 and 61 patients were included in the closed-loop and manual groups, respectively (age: 66 [8] vs 66 [9] years). The primary outcome was observed in 18 (13%) and 10 (16%) patients of the closed-loop and manual groups, respectively (relative risk [95% confidence interval {CI}], 0.77 [0.38-1.57], P = .47). Intraoperative propofol consumption was lower (4.7 [1.4] vs 5.7 [1.4] mg·kg·h, mean difference [MD] [95% CI], -0.73 [-0.98 to -0.48], P < .0001) and the proportion of time within the BIS target range higher (84 [77-89] vs 74 [54-81]%, MD [95% CI], 0.94 [0.67-1.21], P < .0001) in the closed-loop group. CONCLUSIONS: Closed-loop compared to manual BIS-guided total intravenous anesthesia provided a significant reduction in episodes of an excessive depth of anesthesia while decreasing intraoperative propofol requirement but no evidence for a reduction of the incidence of postoperative neurocognitive disordersafter elective major noncardiac surgery was observed.
RCT Entities:
BACKGROUND: The aim of the study was to investigate whether closed-loop compared to manual bispectral index (BIS)-guided target-controlled infusion of propofol and remifentanil could decrease the incidence of postoperative neurocognitive disorders after elective major noncardiac surgery. METHODS:Patients aged >50 admitted for elective major noncardiac surgery were included in a single-blind randomized (ratio 2:1) trial. The anesthetic protocol was allocated by randomization into either closed-loop or manual BIS-guided propofol and remifentanil titration. The BIS target range was 40-60. All patients had cognitive assessment the day before surgery and within 72 hours after surgery using a battery of neuropsychological tests. The primary outcome was the rate of postoperative neurocognitive disorders. Postoperative neurocognitive disorders were defined as a decrease >20% from baseline on at least 3 scores. Intergroup comparison of the primary outcome was performed using the χ test. RESULTS: A total of 143 and 61 patients were included in the closed-loop and manual groups, respectively (age: 66 [8] vs 66 [9] years). The primary outcome was observed in 18 (13%) and 10 (16%) patients of the closed-loop and manual groups, respectively (relative risk [95% confidence interval {CI}], 0.77 [0.38-1.57], P = .47). Intraoperative propofol consumption was lower (4.7 [1.4] vs 5.7 [1.4] mg·kg·h, mean difference [MD] [95% CI], -0.73 [-0.98 to -0.48], P < .0001) and the proportion of time within the BIS target range higher (84 [77-89] vs 74 [54-81]%, MD [95% CI], 0.94 [0.67-1.21], P < .0001) in the closed-loop group. CONCLUSIONS: Closed-loop compared to manual BIS-guided total intravenous anesthesia provided a significant reduction in episodes of an excessive depth of anesthesia while decreasing intraoperative propofol requirement but no evidence for a reduction of the incidence of postoperative neurocognitive disorders after elective major noncardiac surgery was observed.