dc.contributor.author |
Olofsen, E |
en |
dc.contributor.author |
Sleigh, James |
en |
dc.contributor.author |
Dahan, A |
en |
dc.coverage.spatial |
England |
en |
dc.date.accessioned |
2012-02-26T22:36:15Z |
en |
dc.date.issued |
2008-12 |
en |
dc.identifier.citation |
British Journal of Anaesthesia 101(6):810-821 Dec 2008 |
en |
dc.identifier.uri |
http://hdl.handle.net/2292/12016 |
en |
dc.description.abstract |
Background. It would be useful to have an open-source electroencephalographic (EEG) index of g-amino-butyric acid (GABA)-ergic anaesthetic drug effect that is resistant to eye-blink artifact, responds rapidly to changes in EEG pattern, and can be linked to underlying neurophysiological and neuropharmacological mechanisms that control the conscious state. Methods. The EEG waveform can be described as a sequence of ordinal patterns. The permutation entropy (PE) describes the relative occurrence of each of these patterns. It is high ( 1.0) when the signal has predominantly high frequencies and low ( 0.4) when the signal consists of only low frequencies. The response of the PE to various computer-generated EEGlike waveforms was assessed. A composite PE index (CPEI) was developed, which was the sum of two simple PEs and included a small measurement-noise threshold (0.5 mV). We also applied the CPEI to two small pilot EEG data sets from patients receiving sevoflurane (n=21) or propofol (n=9) anaesthesia. Results. With minimal pre-processing or artifact rejection, the CPEI reliably tracked the anaesthetic- related EEG changes, namely loss of high frequencies, spindle-like waves, and delta waves. Using NONMEM, it was possible to construct adequate pharmacokinetic–pharmacodynamic models from the data. The CPEI was comparable with models derived using the bispectral index [BIS R2=0.88 (0.08) vs CPEI R2=0.91 (0.06) for the propofol data] and M-entropy indices [M-entropy R2=0.91 (0.06) vs CPEI R2=0.87 (0.09) for the sevoflurane data]. Conclusions. PE of the EEG shows promise as a simple measure of GABAergic anaesthetic drug effect. |
en |
dc.language |
eng |
en |
dc.publisher |
Oxford University Press |
en |
dc.relation.ispartofseries |
British Journal of Anaesthesia |
en |
dc.rights |
Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated. Previously published items are made available in accordance with the copyright policy of the publisher. Details obtained from: http://www.sherpa.ac.uk/romeo/issn/0007-0912/ |
en |
dc.rights.uri |
https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm |
en |
dc.subject |
Algorithms |
en |
dc.subject |
Anesthetics, General |
en |
dc.subject |
Anesthetics, Inhalation |
en |
dc.subject |
Anesthetics, Intravenous |
en |
dc.subject |
Artifacts |
en |
dc.subject |
Blinking |
en |
dc.subject |
Consciousness |
en |
dc.subject |
Electroencephalography |
en |
dc.subject |
Entropy |
en |
dc.subject |
Humans |
en |
dc.subject |
Methyl Ethers |
en |
dc.subject |
Monitoring, Intraoperative |
en |
dc.subject |
Propofol |
en |
dc.subject |
Signal Processing, Computer-Assisted |
en |
dc.title |
Permutation entropy of the electroencephalogram: a measure of anaesthetic drug effect. |
en |
dc.type |
Journal Article |
en |
dc.identifier.doi |
10.1093/bja/aen290 |
en |
pubs.issue |
6 |
en |
pubs.begin-page |
810 |
en |
pubs.volume |
101 |
en |
dc.rights.holder |
Copyright: Oxford University Press |
en |
dc.identifier.pmid |
18852113 |
en |
pubs.end-page |
821 |
en |
dc.rights.accessrights |
http://purl.org/eprint/accessRights/RestrictedAccess |
en |
pubs.subtype |
Article |
en |
pubs.elements-id |
225634 |
en |
pubs.org-id |
Medical and Health Sciences |
en |
pubs.org-id |
School of Medicine |
en |
pubs.org-id |
Anaesthesiology |
en |
dc.identifier.eissn |
1471-6771 |
en |
dc.identifier.pii |
aen290 |
en |
pubs.record-created-at-source-date |
2012-02-22 |
en |
pubs.dimensions-id |
18852113 |
en |