title: Lessons learned from closed loops in engineering: towards a multivariable approach regulating depth of anaesthesia.
abstract: In this paper is presented a brief state of art regarding the multivariable formulation for controlling the depth of anaesthesia by means of two intravenously administrated drugs, i.e. propofol and remifentanil. In a feasibility study of determining a suitable variable to quantify analgesia levels in patients undergoing cardiac surgery, the bispectral index and an electromyogram-based surrogate variable are proposed as the controlled variables. The study is carried on in the context of implementing a multivariable predictive control algorithm. The simulation results show that such a paradigm is feasible, although it does not guarantee perfect knowledge of the analgesia level-in other words, the variable is not validated against typical evaluations of the pain levels (e.g. clinical scores).
authors.affiliation: Department of Electrical Energy, Systems and Automation, Faculty of Engineering and Architecture, Ghent University, Technologiepark 913, 9052, Gent-Zwijnaarde, Belgium, ClaraMihaela.Ionescu@UGent.be.
authors.forename: Clara M
authors.initials: CM
authors.lastname: Ionescu
authors.forename: Ioana
authors.initials: I
authors.lastname: Nascu
authors.forename: Robin
authors.initials: R
authors.lastname: De Keyser
mesh_terms: D018686:Anesthetics, Intravenous / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*; D003198:Computer Simulation; D056805:Consciousness Monitors; D016903:Drug Monitoring / Q000379:methods*; D004360:Drug Therapy, Computer-Assisted / Q000379:methods*; D004569:Electroencephalography / Q000187:drug effects*; D004576:Electromyography / Q000187:drug effects*; D025461:Feedback, Physiological / Q000502:physiology; D006801:Humans; D008954:Models, Biological; D015999:Multivariate Analysis
chemical_list: D018686:Anesthetics, Intravenous