Feasibility of Closed-loop Titration of Propofol and Remifentanil Guided by the Bispectral Monitor in Pediatric and Adolescent Patients

AbstractAbstract Bispectral index–guided automated control of propofol hypnosis and remifentanil analgesia is feasible and maintains bispectral index in the range of 40 to 60 in 6- to 16-yr-old old patients better than skilled manual control. Propofol consumption during maintenance of anesthesia was similar in the two groups, but remifentanil consumption was higher in the automated control group. Background: This study was designed to assess the feasibility of dual closed-loop titration of propofol and remifentanil guided solely by the Bispectral Index (BIS) monitor in pediatric and adolescent patients during anesthesia. Methods: Children undergoing elective surgery in this single-blind randomized study were allocated into the closed-loop (auto) or manual (manual) group. Primary outcome was the percentage of time with the BIS in the range 40 to 60 (BIS 40–60 ). Secondary outcomes were the percentage of deep (BIS <40 ) anesthesia and drug consumption. Data are presented as median (interquartile range) or number (%). Results: Twenty-three patients (12 [10 to 14] yr) were assigned to the auto group and 19 (14 [7 to 14] yr) to the manual group. The closed-loop controller was able to provide induction and maintenance for all patients. The percentage of time with BIS 40–60 was greater in the auto group (87% [75 to 96] vs. 72% [48 to 79]; P = 0.002), with a decrease in the percentage of BIS <40 (7% [2 to 17] vs . 21% [11 to 38]; P = 0.002). Propofol (2.4 [1.9 to 3.3] vs . 1.7 [1.2 to 2.8] mg/kg) and remifentanil (2.3 [2.0 to 3.0] vs . 2.5 [1.2 to 4.3] μg/kg) consumptions were similar in auto versus manual groups during induction, respectively. During maintenance, propofol consumption (8.2 [6.0 to 10.2] vs . 7.9 [7.2 to 9.1] mg kg −1 h −1 ; P = 0.89) was similar between the two groups, but remifentanil consumption was greater in the auto group (0.39 [0.22 to 0.60] vs . 0.22 [0.17 to 0.32] μg kg −1 min −1 ; P = 0.003). Perioperative adverse events and length of stay in the postanesthesia care unit were similar. Conclusion: Intraoperative automated control of hypnosis and analgesia guided by the BIS is clinically feasible in pediatric and adolescent patients and outperformed skilled manual control.