Skip Navigation



BJA Advance Access published online on September 30, 2005
British Journal of Anaesthesia, doi:10.1093/bja/aei252
This Article
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
95/6/789    most recent
aei252v1
Right arrow E-Letters: Submit a response to the article
Right arrow Alert me when this article is cited
Right arrow Alert me when E-letters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
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 Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Baars, J. H.
Right arrow Articles by Rehberg, B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Baars, J. H.
Right arrow Articles by Rehberg, B.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Board of Management and Trustees of the British Journal of Anaesthesia 2005. All rights reserved. For Permissions, please e-mail: journals.permissions@oxfordjournals.org
Accepted July 8, 2005

Clinical Investigation

Concentration-dependent suppression of F-waves by sevoflurane does not predict immobility to painful stimuli in humans{dagger}

J. H. Baars 1*, D. Kalisch 1, K. F. Herold 1, D. A. Hadzidiakos 1, and B. Rehberg 1

1 Department of Anaesthesiology, Charité Campus Mitte, Schumannstraße 20/21, D-10098 Berlin, Germany

* To whom correspondence should be addressed.
J. H. Baars, E-mail: jan.baars{at}charite.de


  Abstract

Background. Decreased spinal excitability contributes to the immobilizing effects of halogenated ethers during general anaesthesia. Recurrent spinal responses such as F-waves reflect spinal excitability and are suppressed by volatile anaesthetics. To evaluate whether F-waves are suitable for monitoring immobility, the concentration-dependent effects of sevoflurane on F-waves were compared with effects on the Bispectral IndexTM (BISTM). The predictive power of all parameters for movement responses to noxious stimuli was tested. In addition, the effect of the noxious stimulus itself on F-waves was investigated.

Methods. In 28 patients, F-waves were recorded during sevoflurane anaesthesia at a frequency of 0.2 Hz at the lower limb. To insert a laryngeal mask, the sevoflurane concentration was initially increased to ~4%, which caused a complete extinction of F-waves. The sevoflurane concentration was then reduced until the F-waves recovered. BIS and spectral edge frequency (SEF95) were recorded continuously. The t1/2ke0 and EC50 values of the F-wave persistence and amplitude were calculated using a standard pharmacokinetic-pharmacodynamic model. During decreasing sevoflurane concentration motor responses to tetanic electrical stimulation (50 Hz, 60 mA, 5 s, volar forearm) were tested in seven patients and MACtetanus was calculated using logistic regression.

Results. Sevoflurane reduces the F-wave amplitude with an EC50 of 0.79 vol% at a far lower concentration than the calculated MACtetanus (1.5 vol%), whereas the F-wave persistence yields an EC50 of 1.4 vol%. Spinal and EEG parameters predicted the motor responses to movement better than chance alone, but did not differ significantly from each other.

Conclusion. F-waves, especially the F-wave amplitude, cannot be used to predict movement to noxious stimuli during sevoflurane anaesthesia because they are almost completely suppressed at subclinical sevoflurane concentrations. Either the particular motoneurone pool (the largest motoneurones) assessed by F-waves is not involved in generating movement to painful stimuli or direct effects on motoneurone excitability are not involved in the suppression of movement to painful stimuli by sevoflurane.

Keywords: anaesthesia, depth, monitoring; anaesthetics, volatile; measurement techniques, electrophysiology; pain; pharmacokinetics, sevoflurane; spinal cord, reflexes.
{dagger}This work was presented in part at the Meeting of the German Society of Anaesthesiologists, Munich, 2003.
Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 Anesth. Analg.Home page
M. G. Sommers, N.-K. Nguyen, J. G. Veening, K. C. Vissers, M. Ritskes-Hoitinga, and J. van Egmond
Suppression of Noxious-Induced C-Fos Expression in the Rat Lumbar Spinal Cord by Isoflurane Alone or Combined with Fentanyl
Anesth. Analg., April 1, 2008; 106(4): 1303 - 1308.
[Abstract] [Full Text] [PDF]

Home page
 Br J AnaesthHome page
R. R. Kennedy, C. Minto, and A. Seethepalli
Effect-site half-time for burst suppression is longer than for hypnosis during anaesthesia with sevoflurane
Br. J. Anaesth., January 1, 2008; 100(1): 72 - 77.
[Abstract] [Full Text] [PDF]

Home page
 Br J AnaesthHome page
M. Rantanen, H. Ypparila-Wolters, M. van Gils, A. Yli-Hankala, M. Huiku, M. Kymalainen, and I. Korhonen
Tetanic stimulus of ulnar nerve as a predictor of heart rate response to skin incision in propofol remifentanil anaesthesia
Br. J. Anaesth., October 1, 2007; 99(4): 509 - 513.
[Abstract] [Full Text] [PDF]

Home page
 Br J AnaesthHome page
J. G. C. Lerou and J. Mourisse
Applying a physiological model to quantify the delay between changes in end-expired concentrations of sevoflurane and bispectral index
Br. J. Anaesth., August 1, 2007; 99(2): 226 - 236.
[Abstract] [Full Text] [PDF]

Home page
 Br J AnaesthHome page
J. Mourisse, J. Lerou, M. Struys, M. Zwarts, and L. Booij
Multi-level approach to anaesthetic effects produced by sevoflurane or propofol in humans: 1. BIS and blink reflex
Br. J. Anaesth., June 1, 2007; 98(6): 737 - 745.
[Abstract] [Full Text] [PDF]

Home page
 Br J AnaesthHome page
J. Mourisse, J. Lerou, M. Struys, M. Zwarts, and L. Booij
Multi-level approach to anaesthetic effects produced by sevoflurane or propofol in humans: 2. BIS and tetanic stimulus-induced withdrawal reflex
Br. J. Anaesth., June 1, 2007; 98(6): 746 - 755.
[Abstract] [Full Text] [PDF]

Home page
 Br J AnaesthHome page
J. H. Baars, S. Tas, K. F. Herold, D. A. Hadzidiakos, and B. Rehberg
The suppression of spinal F-waves by propofol does not predict immobility to painful stimuli in humans{dagger}
Br. J. Anaesth., January 1, 2006; 96(1): 118 - 126.
[Abstract] [Full Text] [PDF]


Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.