Controlling the depth of anesthesia by a novel positive control strategy

Abstract

In this paper a positive control law is designed for multi-input positive systems that ensures asymptotic tracking of a desired output reference value.This control law can be viewed as a generalization of another one proposed in the literature for the control of the total mass in SISO compartmental systems, but is suitable for a wider class of positive systems. The controller proposed here is applied to the control of the depth of anesthesia (DoA), by means of the administration of propofol and remifentanil, when using a parameter parsimonious Wiener model recently introduced in the literature.Its performance is illustrated by realistic simulations.

Positive state observer for the automatic control of the depth of anesthesia—Clinical results

“…In Nogueira et al [17] a control law was proposed for the BIS tracking of patients, during general anesthesia, by means of the automatic administration of both the hypnotic (propofol) and the analgesic (remifentanil). Moreover, this controller has the advantage of allowing di erent combinations of the two drugs in order to obtain the same value for the BIS level, and allows the changing of the desired reference value for the BIS during the surgical procedure.…”

Robustness of a new nonlinear positive controller for BIS tracking

“…In this paper, the robustness of the nonlinear control law proposed in [1], in order to control the BIS level of patients by means of simultaneous administration of propofol and remifentanil, was studied. It was theoretically proven that even in the presence of model uncertainties, the BIS of the patient converges to an interval that contains the desired reference value for the BIS.…”

“…In order to track a desired reference value for the BIS level, by means of simultaneous administration of propofol and of remifentanil, a nonlinear controller was presented in [1] (see also [13]). This controller results from a combination of a linear control law with a positivity constraint for the drug doses.…”

“…It was proven in [1] that if in steady state M (x) =M , then the steady state BIS of the patient,z, is equal toz = Q c c c a…”

“…A nonlinear automatic positive control law to track a desired BIS level, by means of the administration of the analgesic remifentanil and the hipnotic propofol, was designed in [1]. This controller, already successfully implemented in clinical environment, is based on the parameter parsimonious model (PPM) (see [7]).…”