Skip Navigation


BJA Advance Access originally published online on June 19, 2009
British Journal of Anaesthesia 2009 103(3):387-393; doi:10.1093/bja/aep162
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
103/3/387    most recent
aep162v1
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 Lysakowski, C.
Right arrow Articles by Tramèr, M. R.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Lysakowski, C.
Right arrow Articles by Tramèr, M. R.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?


© The Author [2009]. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournal.org

Bispectral and spectral entropy indices at propofol-induced loss of consciousness in young and elderly patients

C. Lysakowski1,*, N. Elia3, C. Czarnetzki1, L. Dumont1, G. Haller1,2, C. Combescure2 and M. R. Tramèr1,3

1 Division of Anaesthesiology and
2 Clinical Trial Unit, University Hospitals of Geneva, rue Gabrielle Perret-Gentil 4, CH-1211 Geneva 14, Switzerland
3 Medical Faculty, University of Geneva, Geneva, Switzerland

* Corresponding author. E-mail: christopher.lysakowski{at}hcuge.ch

Background: Bispectral (BIS) and state/response entropy (SE/RE) indices have been widely used to estimate depth of anaesthesia and sedation. In adults, independent of age, adequate and safe depth of anaesthesia for surgery is usually assumed when these indices are between 40 and 60. Since the EEG is changing with increasing age, we investigated the impact of advanced age on BIS, SE, and RE indices during induction.

Methods: BIS and SE/RE indices were recorded continuously in elderly (≥65 yr) and young (≤40 yr) surgical patients who received propofol until loss of consciousness (LOC) using stepwise increasing effect-site concentrations. LOC was defined as an observer assessment of alertness/sedation score <2, corresponding to the absence of response to mild prodding or shaking.

Results: We analysed 35 elderly [average age, 78 yr (range, 67–96)] and 34 young [35 (19–40)] patients. At LOC, all indices were significantly higher in elderly compared with young patients: BISLOC, median 70 (range, 58–91) vs 58 (40–70); SELOC, 71 (31–88) vs 55.5 (23–79); and RELOC, 79 (35–96) vs 59 (25–80) (P<0.001 for all comparisons). With all three monitors, only a minority of elderly patients lost consciousness within a 40–60 index range: two (5.7%) with BIS and RE each, and seven (20%) with SE. In young patients, the respective numbers were 20 (58.8%) for BIS, 13 (38.2%) for SE, and nine (26.5%) for RE.

Conclusions: In adults undergoing propofol induction, BIS, SE, and RE indices at LOC are significantly affected by age.

Keywords: brain, electroencephalography; drug delivery, infusion; monitoring, depth of anaesthesia


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




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.