Automatic control of consciousness using the BIS is clinically feasible and outperforms manual control.

The controller allows the automated delivery of propofol and remifentanil and maintains BIS values in predetermined boundaries during general anesthesia better than manual administration.

Background: This randomized controlled trial describes automated coadministration of propofol and remifentanil, guided by M-Entropy analysis of the electroencephalogram. The authors tested the hypothesis that a novel dual-loop controller with an M-Entropy monitor increases time spent within predetermined target entropy ranges. Methods: Patients scheduled for elective surgery were randomly assigned in this single-blind study using a computergenerated list, to either dual-loop control using a proportional-integral-derivative controller or skilled manual control of propofol and remifentanil using target-controlled-infusion systems. In each group, propofol and remifentanil administration was titrated to a state entropy target of 50 and was subsequently targeted to values between 40 and 60. The pri-

No abstract

The system was able to allow induction clinically for all patients. Automated titration guided by Bispectral Index for propofol infusion was feasible without increase in haemodynamic adverse effects.