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Automatic control of anesthesia using two feedback variables.

G F Schils·F J Sasse·V C Rideout
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Abstract

A new controller of an ON/OFF type was implemented for halothane anesthesia. A proportional-plus-integral controller with time-delay compensation proved not to be robust enough for the known clinical situation, as shown both in computer simulations and in animal trials. The ON/OFF controller proved to be less sensitive to parameter mismatches, and repeated animal trials showed a short response time and acceptable steady-state tracking. A method for switching the controlled effect of the drug was also developed, since anesthetic agents have multiple effects. Mean arterial blood pressure and a measure of EEG frequency were chosen as controlled variables, both being depressed by halothane. A coordinator forces the system state as near the desired values of these variables as possible, given that only one drug is used.

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AlgorithmsAnesthesia, InhalationAnimalsBiomedical EngineeringBlood PressureDogsElectroencephalographyFeedbackHalothaneHumansSoftwareJournal ArticleResearch Support, Non-U.S. Gov't

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G F Schils, F J Sasse, V C Rideout. 1987. Automatic control of anesthesia using two feedback variables.. https://doi.org/10.1007/bf02364165

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