Permutation auto-mutual information of electroencephalogram in anesthesia.
OBJECTIVE
The dynamic change of brain activity in anesthesia is an interesting topic for clinical doctors and drug designers. To explore the dynamical features of brain activity in anesthesia, a permutation auto-mutual information (PAMI) method is proposed to measure the information coupling of electroencephalogram (EEG) time series obtained in anesthesia.


METHODS
The PAMI is developed and applied on EEG data collected from 19 patients under sevoflurane anesthesia. The results are compared with the traditional auto-mutual information (AMI), SynchFastSlow (SFS, derived from the BIS index), permutation entropy (PE), composite PE (CPE), response entropy (RE) and state entropy (SE). Performance of all indices is assessed by pharmacokinetic/pharmacodynamic (PK/PD) modeling and prediction probability.


RESULTS
The PK/PD modeling and prediction probability analysis show that the PAMI index correlates closely with the anesthetic effect. The coefficient of determination R(2) between PAMI values and the sevoflurane effect site concentrations, and the prediction probability Pk are higher in comparison with other indices. The information coupling in EEG series can be applied to indicate the effect of the anesthetic drug sevoflurane on the brain activity as well as other indices. The PAMI of the EEG signals is suggested as a new index to track drug concentration change.


CONCLUSIONS
The PAMI is a useful index for analyzing the EEG dynamics during general anesthesia.
Institute of Electrical Engineering, Yanshan University, Qinhuangdao 066004, People's Republic of China.
Zhenhu
Z
Liang
Yinghua
Y
Wang
Gaoxiang
G
Ouyang
Logan J
LJ
Voss
Jamie W
JW
Sleigh
Xiaoli
X
Li
D000293:Adolescent; D000328:Adult; D000465:Algorithms; D000758:Anesthesia; D000777:Anesthetics / Q000493:pharmacokinetics / Q000494:pharmacology; D001921:Brain / Q000187:drug effects / Q000502:physiology; D056805:Consciousness Monitors; D003627:Data Interpretation, Statistical; D004305:Dose-Response Relationship, Drug; D004566:Electrodes; D004569:Electroencephalography / Q000379:methods / Q000706:statistics & numerical data*; D001330:Electronic Data Processing / Q000379:methods* / Q000706:statistics & numerical data; D019277:Entropy; D005260:Female; D005544:Forecasting; D005712:Galvanic Skin Response / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D055815:Young Adult
D000777:Anesthetics