The authors are developing a closed-loop system for intravenous anesthesia in humans. Using published pharmacokinetic data for the intravenous anesthetic agent, propofol, they have generated a population of “virtual patients” and simulated their response to induction and maintenance of intravenous anesthesia using a feedback system based on an electroencephalogram derivative. Their simulations suggested that the proposed system would accommodate patients with widely varying pharmacokinetic characteristics. The system was subsequently tested in humans, and successfully induced and maintained anesthesia in 7 volunteers.
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