Title
Optimized PID control of depth of hypnosis in anesthesia.
Abstract
This paper deals with the use of proportional-integral-derivative controllers for the closed-loop control of the depth of hypnosis in anesthesia by using propofol administration and the bispectral index as a controlled variable.The controller parameters are optimized by using genetic algorithms and it is shown that a gain scheduling strategy should be employed to address the induction and maintenance phases separately.The selection of the filter on the controller output is also considered and the trade-off between the performance and the noise effect in the control variable is analyzed. Background and Objective: This paper addresses the use of proportional-integral-derivative controllers for regulating the depth of hypnosis in anesthesia by using propofol administration and the bispectral index as a controlled variable. In fact, introducing an automatic control system might provide significant benefits for the patient in reducing the risk for under- and over-dosing.Methods: In this study, the controller parameters are obtained through genetic algorithms by solving a min-max optimization problem. A set of 12 patient models representative of a large population variance is used to test controller robustness. The worst-case performance in the considered population is minimized considering two different scenarios: the induction case and the maintenance case.Results: Our results indicate that including a gain scheduling strategy enables optimal performance for induction and maintenance phases, separately. Using a single tuning to address both tasks may results in a loss of performance up to 102% in the induction phase and up to 31% in the maintenance phase. Further on, it is shown that a suitably designed low-pass filter on the controller output can handle the trade-off between the performance and the noise effect in the control variable.Conclusions: Optimally tuned PID controllers provide a fast induction time with an acceptable overshoot and a satisfactory disturbance rejection performance during maintenance. These features make them a very good tool for comparison when other control algorithms are developed.
Year
DOI
Venue
2017
10.1016/j.cmpb.2017.03.013
Computer Methods and Programs in Biomedicine
Keywords
Field
DocType
Depth of hypnosis control,Gain scheduling,Genetic algorithms,PID control
Population,Control theory,PID controller,Control theory,Gain scheduling,Computer science,Overshoot (signal),Population variance,Anesthesia,Automatic control,Control variable
Journal
Volume
Issue
ISSN
144
C
0169-2607
Citations 
PageRank 
References 
6
0.52
12
Authors
6
Name
Order
Citations
PageRank
Fabrizio Padula13111.59
Clara M. Ionescu235162.42
N. Latronico3122.71
Massimiliano Paltenghi4122.38
Antonio Visioli522440.89
Giulio Vivacqua660.52