CJA
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
This Article
Right arrow Full Text (PDF)
Right arrow Submit a scholarly reply
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Porkkala, T.
Right arrow Articles by Jantti, V.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Porkkala, T.
Right arrow Articles by Jantti, V.

Canadian Journal of Anesthesia, Vol 44, 963-968, Copyright © 1997 by Canadian Anesthesiologists' Society

ARTICLES

Median nerve somatosensory evoked potentials during isoflurane anaesthesia

T Porkkala, S Kaukinen, V Hakkinen and V Jantti
International Graduate School in Neurosciences, University of Tampere, Finland.

PURPOSE: The effect of isoflurane on the subcortical P14 component of the median nerve somatosensory evoked potential (SEP) is poorly known. We studied whether the P14 wave from the upper brainstem, recorded with a nasopharyngeal electrode, was attenuated at the isoflurane-induced EEG burst-suppression level. We also compared the effect of isoflurane on the P14, cervical N13 and cortical N20, N35 and N6, components. METHODS: Seventeen elective patients were anaesthetized with isoflurane. Somatosensory evoked potentials were recorded prior to anaesthesia, at 0.5 MAC and 1 MAC end-tidal isoflurane as well as at the level when EEG was in burst-suppression (mean 1.9 vol% end-tidal isoflurane). RESULTS: Isoflurane had varying effects on the subcortical components of median SEP. The amplitude of nasopharyngeal P14 was stable, but the mean latency increased from 14.4 +/- 1.2 msec at 0.5 MAC to 15.2 +/- 1.1 msec at burst-suppression level (P < 0.05). In contrast, the N13 neck response amplitude was attenuated from 3.3 +/- 0.6 microV to 2.6 +/- 0.5 microV (P < 0.005) without latency changes. The latency of the cortical N20 wave was increased from 19.7 +/- 1.1 msec at awake to 24.4 +/- 1.6 msec at burst-suppression level (P < 0.0001) and amplitude was reduced from 3.3 +/- 1.1 microV to 1.3 +/- 0.6 microV (P < 0.0001). The later cortical components were attenuated even during 0.5 MAC isoflurane and were not recordable during EEG burst-suppression. CONCLUSION: We conclude that P14 can reliably be recorded with nasopharyngeal electrodes during isoflurane anaesthesia, even during EEG burst-suppression, when the N20 wave is attenuated. In contrast, the middle-latency SEP components are sensitive to isoflurane anaesthesia.


This article has been cited by other articles:


Home page
 Br J AnaesthHome page
E. H. C. Liu, H. K. Wong, C. P. Chia, H. J. Lim, Z. Y. Chen, and T. L. Lee
Effects of isoflurane and propofol on cortical somatosensory evoked potentials during comparable depth of anaesthesia as guided by bispectral index
Br. J. Anaesth., February 1, 2005; 94(2): 193 - 197.
[Abstract] [Full Text] [PDF]

Home page
 Br J AnaesthHome page
D. J. A. Vaughan, C. Thornton, D. R. Wright, J. R. Fernandes, P. Robbins, C. Dore, and M. D. Brunner
Effects of different concentrations of sevoflurane and desflurane on subcortical somatosensory evoked responses in anaesthetized, non-stimulated patients
Br. J. Anaesth., January 1, 2001; 86(1): 59 - 62.
[Abstract] [Full Text] [PDF]

Home page
 NeurologyHome page
A. L. Sherman, D. L. Tirschwell, P. J. Micklesen, W. T. Longstreth Jr., and L. R. Robinson
Somatosensory potentials, CSF creatine kinase BB activity, and awakening after cardiac arrest
Neurology, February 22, 2000; 54(4): 889 - 894.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1997 by the Canadian Anesthesiologists' Society.