Model-Based Approach on the Effect of Isoflurane and Control of Critical Hemodynamic Variables

Abstract

Monitoring and control of physiological variables during surgeries is a difficult task since the manual infusion of drugs leads to complications in patients. Anaesthesia is mainly used to maintain most the critical physiological parameters. Automatic control of these para meters will help the anaesthetist to focus on other issues that has to be taken care of. This paper presents about the closed loop control of anaesthesia drug that is used to maintain the safety limits of physiological variables such as hypnosis in terms of Bi-Spectral Index (BIS), analgesia in terms of Mean Arterial Pressure (MAP) and Heart Rate (HR). Here isoflurane is anaesthesia that is used as the medicine to administer the parameters. Pharma cokinetic (PK) and Pharmacodynamic (PD) modeling is carried out for isoflurane drug and control action is implemented based on the open loop response of the PK-PD model. The performance of the model is compared for Proportional-Integral (PI) controller and Neural Network Internal Model Control (NN-IMC) and the simulation results are obtained using MATLAB.