[Evaluation of the sedation level with propofol with electroencephalographic Entropy in comparison with bispectral index monitor].
BACKGROUND
Entropy, a newly available electroencephalographic monitor, demonstrates two parameters, response entropy (RE) and state entropy (SE). The aim of this study is to compare RE and SE with bispectral index (BIS) during anesthetic induction with propofol.


METHODS
Fifteen patients received target controlled infusion of propofol starting at 3 microg x ml(-1). We measured RE, SE and BIS and recorded effect-site concentrations of propofol at three sedation levels: VR1; conscious state before infusion of propofol, VR2; no response to verbal command, and VR3; no response to verbal command and shaking. Spearman rank correlations and prediction probability for sedation level were analyzed.


RESULTS
Effect-site concentrations of propofol at VR1, VR2, and VR3 were 0, 1.8 +/- 0.7, and 2.4 +/- 0.7, respectively. All three parameters showed significant correlations with sedation levels. Prediction probability values of SE, RE, and BIS were 0.905, 0.894, and 0.890, respectively.


CONCLUSIONS
Response entropy and SE can provide similar information as BIS about the sedation level with propofol.
Fukuda
Hideki
H
Department of Anesthesiology and Critical Care, Division of Clinical Medical Science, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima 734-8551.
Kurita
Shigeaki
S
Kawamoto
Masashi
M
Yuge
Osafumi
O
D000328:Adult; D000368:Aged; D016292:Procedural Sedation; D004569:Electroencephalography / Q000379:methods*; D019277:Entropy; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D015742:Propofol / Q000008:administration & dosage
D006993:Hypnotics and Sedatives; D015742:Propofol