Nitrous oxide does not alter bispectral index: study with nitrous oxide as sole agent and as an adjunct to i.v. anaesthesia
Language: 
English
Short Title: 
Nitrous oxide does not alter bispectral index
Abstract: 

We have studied the effect of nitrous oxide on bispectral index (BIS), calculated from a bipolar encephalogram. Inhalation of 70% nitrous oxide resulted in loss of consciousness in all healthy volunteers (n = 10) but no change in BIS. Brief inhalation up to 1.2% sevoflurane also resulted in loss of consciousness in volunteers (n = 5), but with sevoflurane, BIS decreased. BIS and the haemodynamic effects of adding nitrous oxide were also measured during coronary artery bypass surgery in patients (n = 10) receiving midazolam and fentanyl infusions. Measurements were made after 0%, 33%, 66% and 0% nitrous oxide, just before skin incision and after sternotomy. Nitrous oxide caused no change in BIS. BIS may indicate a sufficient hypnotic depth to prevent awareness during surgery, but our study demonstrated that pharmacological unconsciousness-hypnosis can also be reached by mechanisms to which BIS is not sensitive. Thus BIS is a sufficient but not a necessary criterion for adequate depth of anaesthesia or prevention of awareness.

Author(s): 
Barr, G.
Jakobsson, J. G.
Owall, A.
Anderson, R. E.
Item Type: 
Journal Article
Publication Title: 
British Journal of Anaesthesia
Journal Abbreviation: 
Br J Anaesth
Publication Date: 
Jun-99
Publication Year: 
1999
Pages: 
827-830
Volume: 
82
Issue: 
6
ISSN: 
0007-0912
Library Catalog: 
PubMed
Extra: 
PMID: 10562773

Turabian/Chicago Citation

G. Barr, J. G. Jakobsson, A. Owall and R. E. Anderson. Jun-99. "Nitrous oxide does not alter bispectral index: study with nitrous oxide as sole agent and as an adjunct to i.v. anaesthesia." British Journal of Anaesthesia 82: 6: 827-830.

Wikipedia Citation

<ref> {{Cite journal | doi = | issn = 0007-0912 | volume = 82 | pages = 827-830 | last = Barr | first = G. | coauthors = Jakobsson, J. G., Owall, A., Anderson, R. E. | title = Nitrous oxide does not alter bispectral index: study with nitrous oxide as sole agent and as an adjunct to i.v. anaesthesia | journal = British Journal of Anaesthesia | date = Jun-99 | pmid = | pmc = }} </ref>