Closed-loop feedback control of methohexital anesthesia by quantitative EEG analysis in humans.

摘要: A combined pharmacokinetic and pharmacodynamic model of methohexital was used to establish evaluate feedback control anesthesia in 13 volunteers. The median frequency the EEG power spectrum served as variable constituting feedback. Median values from 2-3 Hz were chosen desired level (set-point). In 11 volunteers, system succeeded maintaining a satisfactory depth (i.e., unresponsiveness verbal commands tactile stimuli). During control, 75% all measured preset range Hz. This distribution obtained by applying random stimulation (six different acoustic stimuli) volunteers approximately every 1.5 min. decrease baseline anesthetic primarily induced increasing fractional band 0.5-2 12.6 +/- 4.5% (mean SD) 46.0 2.5%. time recovery (as defined opening eyes on command) after cessation period 20.6 min (10.7-44.5 min) when 5.2 (4.7-8.4 Hz). average requirement during 2 h 1.02 0.16 g. It is concluded that pharmacokinetic-pharmacodynamic models intravenous anesthetics established previously may be form suitable background for model-based quantitative analysis. approach gives possible solution problem adapting data individuals using population mean starting drug therapy.