Design And Research Of Propofol Closed-loop Control System

With the rapid development of medical science,anesthesia technology is also progressing.But from a clinical perspective speaking,traditional anesthetic administration method is still a lack of a unified quantitative index about depth of anesthesia,which can easily put patients at risk.In view of this situation,this paper intends to combine automatic control technology with clinical anesthesia to design an anesthesia closed-loop control system,which is capable of precise and automatic anesthetic administration.Taking into account the differences in anesthetic drug models among children,adults and the elderly,anesthesia closed-loop control for patients of different ages should be designed,represpectively.Due to the fact that the individual differences of the elderly are obvious and they are extremely vulnerable to other basic diseases,the anesthesia closed-loop control for children and adults were designed in the paper.The specific research work is as follows:Firstly,before designing the anesthesia closed-loop control about adults,we need to find a pharmacokinetics-pharmacodynamics model that can be used to describe the entire process of anesthetic drug metabolism in patients' body.At present,bispectral index is widely used in pharmacokinetics-pharmacodynamics model about adults,but there are shortcomings of segment abnormalities and output delay.However,previous studies have shown that the Tsallis permutation entropy and permutation entropy have the good characteristics of distinguishing the patients' different anesthesia status,so we consider to model pharmacokinetics-pharmacodynamics models about adults based on Tsallis permutation entropy and permutation entropy,respectively.Secondly,this paper combines the neural network algorithm,adaptive control algorithm with sliding mode control algorithm to control the pharmacokineticspharmacodynamics model of adults obtained from modeling,in the meantime,performance of PID control was explored in the anesthesia control system.Because it is difficult to achieve optimal results by using the traditional manual adjustment method for PID parameters,this paper uses ant colony optimization algorithm to optimize the PID parameters,then the pharmacokinetics-pharmacodynamics model of adults obtained by modeling is controlled and simulated.Finally,an artificial disturbance was added in anesthesia closed-loop control based on the different control algorithms to test the antijamming performance of the system,then the control results were compared and analyzed,and the best anesthesia closed-loop control strategy for adults was found.Next,in order to find better pediatric anesthesia closed-loop control state observation indexes,the performance about SynchFastSlow ratio,Tsallis permutation entropy,permutation entropy,PowerFastSlow ratio,? ratio,spectral edge frequency and bispectral index were studied in monitoring pediatric sedation status.The results showed that Tsallis permutation entropy can better monitor the pediatric anesthesia status.Finally,before designing pediatric anesthesia closed-loop control,according to the pharmacokinetics-pharmacodynamics model of adults,this paper considers to model the pediatric pharmacokinetics-pharmacodynamics model based on bispectral index and Tsallis permutation entropy,represpectively.Then pediatric pharmacokinetics-pharmacodynamics model was controlled by ant colony optimization PID algorithm.Finally the control results was evaluated through statistical analysis.