[Effects of desflurane on auditory evoked potential index and quantitative electroencephalogram].
OBJECTIVE
To observe the effects of desflurane on A-line ARX Index (AAI), QEEG, MAP and HR, and to investigate the feasibility of AAI, QEEG, MAP and HR in monitoring the depth of anesthesia with desflurane.


METHODS
Thirty patients classified as ASA physical status I approximately II were scheduled for elective lower abdominal surgery. Anesthesia was induced with propofol and vecuronum. After the tracheal intubation, the lungs were ventilated with desflurane in oxygen. End-tidal desflurane concentrations were maintained at 0.8, 1.0 and 1.3 MAC for 20 minutes, respectively. The parameters of record included AAI, BIS (bispectral index), SEF (95% spectral edge freqency), MF (midian freqency), MAP and HR.


RESULTS
AAI, BIS, SEF and MF significantly decreased in a linear manner (r = 0.830, 0.930, 0.803, and 0.885, respectively, P < 0.01) with increasing end-tidal concentration of desflurane range of 0.8 approximately 1.3 MAC. MAP and HR did not change much. HR increased significantly at concentration 1.3 MAC than that of 1.0 MAC.


CONCLUSIONS
Within end-tidal desflurane concentration range 0.8 approximately 1.3 MAC, both AAI and parameters derived from EEG (such as BIS, SEF, MF) can serve as parameters in monitoring the depth of anesthsia with desflurane, while MAP and HR can not.
Xu
Yu-Guang
YG
Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha 410008, China.
Guo
Qu-Lian
QL
Wang
Yan-Qing
YQ
D000005:Abdomen / Q000601:surgery; D000328:Adult; D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D000077335:Desflurane; D004569:Electroencephalography / Q000187:drug effects* / Q000379:methods; D005072:Evoked Potentials, Auditory / Q000187:drug effects*; D005260:Female; D006801:Humans; D007530:Isoflurane / Q000031:analogs & derivatives* / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods
D018685:Anesthetics, Inhalation; D000077335:Desflurane; D007530:Isoflurane