MODELING AND CONTROL OF ANAESTHETICS DURING POST SURGICAL TREATMENT

Abstract

The major constraint in automatic control of anaesthesia is patient’s variability based on drug tolerance. A controller has to be designed in such way that it is robust to the actual patient’s response even if the controller is designed based on a nominal patient model. Anaesthetic agent used in this study is isoflurane gas and the controlled delivery of anaesthetic agent has to be given with utmost care of great accuracy because the agents used here have narrow therapeutic uses. The importance of the robustness of the controller to be designed is that it must provide a sufficient and controlled administration of drugs to avoid the situations of under and over dosing of patients. The hemodynamic parameters that are to be measured during drug administration is Mean Arterial Pressure (MAP) and heart rate (HR), whereas another parameter to be measured during anaesthesia delivery is measure of unconsciousness of the patient called asBi-spectral Index (BIS). In this study, the anaesthesia control system is modeled and controller design is made for patient undergoing Intensive Care Treatment (ICU) after valve replacement surgery. The background analysis is made by observing the realtimeparameters such as BIS, MAP, and HR of patient undergone valve replacement surgery.