• Yoshihito Sawaguchi, Eiko Furutani, Gotaro Shirakami, Mithuiko Araki, and Kazhuiko Fukuda.
• Department of Control Engineering, Kisarazu National College of Technology, 2-11-1 Kiyomidai-higashi, Kisarazu-shi, Chiba 292-0041, Japan. sawaguti@d.kisarazu.ac.jp
• IEEE Trans Biomed Eng. 2008 Mar 1;55(3):874-87.

AbstractIn ambulatory surgery, anesthetic drugs must be administered at a suitable rate to prevent adverse reactions after discharge from the hospital. To realize more appropriate anesthesia, we have developed a hypnosis control system, which administers propofol as an anesthetic drug to regulate the bispectral index (BIS), an electroencephalography (EEG)-derived index reflecting the hypnosis of a patient. This system consists of three functions: 1) a feedback controller using a model-predictive control method, which can adequately accommodate the effects of time delays; 2) a parameter estimation function of individual differences; and 3) a risk control function for preventing undesirable states such as drug overinfusion or intraoperative arousal. With the approval of the ethics committee of our institute, 79 clinical trials took place since July 2002. The results show that our system can reduce the total amount of propofol infusion and maintain the BIS more accurately than anesthesiologist's manual adjustment.

33 keywords...

hide…