Control strategies in general anesthesia administration

Every year, 230 million anesthetic procedures take place worldwide. Advances in technology and medicine have not yet been able to eradicate risks of mortality and major complications associated to anesthesia. Medication errors, overdose, and adverse effects often lead to such undesired events. Today, the procedure of anesthesia administration relies greatly on the anesthetists' experience and subjective interpretation of the patient response to drugs and surgical stimuli. Interpatient variability and narrow therapeutic ranges of drugs represent further difficulties to the selection of the optimal drug dose.The introduction of control systems in several fields of human life has resulted in improved performances and safety levels, and lower costs. We believe that these effects can be extended to general anesthesia administration.This chapter compares the state of the art in anesthesia delivery with closed-loop control of intravenous anesthesia and discusses different strategies employed by researchers. Among these, special focus is devoted to the advantages of model-predictive control. Afterwards, model-predictive control application to anesthesia coadministered with propofol and remifentanil is proposed and analyzed. Physiologically based pharmacokinetic modeling allows achieving an increased level of individualization for the response prediction, which is a primary issue because of interindividual variability of patients. Finally, we provide a short discussion on the ethical problem that comes with the application of control systems in this field.