Osamu Nagata1, Yuka Matsuki2, Yoshihiro Ogino3, Kenji Shigemi2. 1. Department of Anesthesiology, Center Hospital of the National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku, Tokyo, 162-8655, Japan. o-nagata@fa2.so-net.ne.jp. 2. Department of Anesthesiology and Reanimatology, University of Fukui Hospital, Fukui, Japan. 3. Ventilator and Anesthesia Device Business Operations, Nihon Kohden Corporation, Tokyo, Japan.
Abstract
PURPOSE: We have developed an automated anesthesia control system that uses biological information to provide closed-loop control of drug administration for total intravenous anesthesia with propofol, remifentanil, and rocuronium. In this study, we investigated whether the control of sedatives, analgesics, and muscle relaxants delivered by this system is non-inferior to that delivered by anesthesiologists. METHODS: During anesthesia management by our automated administration control system and by anesthesiologists, the concentration of each drug at the site of effect (calculated from drug administration history) and biometric information (bispectral index, blood pressure, pulse rate, and single contraction ratio %T1) were tabulated during the period from the start to end of surgery. The primary efficacy endpoint was the ratio of adequate anesthesia time, in which all three factors of sedation, analgesia, and muscle relaxation were maintained within the target range, to the period from the start to end of surgery under total intravenous anesthesia. RESULTS: Percentage of time under appropriate anesthesia was 73.24 ± 17.24 in the automatic group (n = 28) and 59.94 ± 29.06 in the manual group (n = 28). The lower limit of the 97.5% one-sided confidence interval for the difference between the two group means was 0.51%, indicating the non-inferiority of the automatic group to the manual group (p = 0.002). The incidence of adverse events did not differ significantly between the groups. CONCLUSION: The clinical use of our automated anesthesia control system should allow for the maintenance of adequate anesthesia by adjusting the doses of intravenous anesthetics in the same way as anesthesiologists do.
PURPOSE: We have developed an automated anesthesia control system that uses biological information to provide closed-loop control of drug administration for total intravenous anesthesia with propofol, remifentanil, and rocuronium. In this study, we investigated whether the control of sedatives, analgesics, and muscle relaxants delivered by this system is non-inferior to that delivered by anesthesiologists. METHODS: During anesthesia management by our automated administration control system and by anesthesiologists, the concentration of each drug at the site of effect (calculated from drug administration history) and biometric information (bispectral index, blood pressure, pulse rate, and single contraction ratio %T1) were tabulated during the period from the start to end of surgery. The primary efficacy endpoint was the ratio of adequate anesthesia time, in which all three factors of sedation, analgesia, and muscle relaxation were maintained within the target range, to the period from the start to end of surgery under total intravenous anesthesia. RESULTS: Percentage of time under appropriate anesthesia was 73.24 ± 17.24 in the automatic group (n = 28) and 59.94 ± 29.06 in the manual group (n = 28). The lower limit of the 97.5% one-sided confidence interval for the difference between the two group means was 0.51%, indicating the non-inferiority of the automatic group to the manual group (p = 0.002). The incidence of adverse events did not differ significantly between the groups. CONCLUSION: The clinical use of our automated anesthesia control system should allow for the maintenance of adequate anesthesia by adjusting the doses of intravenous anesthetics in the same way as anesthesiologists do.