Modelling of Target-Controlled Infusion of Propofol for Depth-of-Anaesthesia Simulation in Matlab-Simulink

Total intravenous anaesthesia (TIVA) is an anaesthesiologic technique, where substances are injected intravenously. The anaesthesiologist adjusts the injection of intravenous anaesthetic agents regarding the depth of anaesthesia. In the paper, we present a model of an anaesthetic agent, namely propofol, influencing the depth of anaesthesia. The influence of propofol is linked to the concentration of the drug in the appropriate compartment. First, the modelling of pharmacokinetics of propofol is introduced. The 3-compartmental model and the effect-site model are presented, the relevant model parameters are given. Next, the model is verified by comparing the simulation results to the data file that was recorded by the Orchestra Base Primea infusion workstation during a medical procedure, which lasted about 40 minutes. The simulation results are presented and the predictive quality of the model is evaluated. The presented model for Matlab-Simulink provides a basic tool for further researching the dynamics of anaesthetic depth. Despite the fact that more data must be obtained in order to properly validate the model, the presented model provides a basis for running simulations and testing various scenarios of propofol administration and is usable for developing and testing closed-loop control approaches for automatic control of depth of anaesthesia.