Control of anaesthesia concentration using model based controller

Administration of Anaesthesia is important for both surgery and intensive care. The intravenous anaesthetics are widely used to provide rapid onset, stable maintenance, and rapid recovery compared with inhaled anaesthetics. The aim of the project is to investigate a reliable and safe methodology for delivering total intravenous anaesthesia using closed loop control technology and bispectral analysis of human electroencephalogram (EEG) waveform. In this work a Bispectral Index (BIS), derived from power spectral and bispectral analysis on EEG waveform, is used to measure the depth of anaesthesia.. In comparison with conventional method, drug effect is measured during drug infusion in closed loop anaesthesia. This may provide superior safety, better patient care, better quality of anaesthesia. Main advantage of this method is to make recurrent and minor alterations to anaesthetic drug. A model based controller is used to control the drug infusion rate. The performance of the model based controller is compared with the PID controller. The results show that the model based controller gives better performance than others controllers and it reduces rise time, settling time and peak time.