Bispectral index changes following etomidate induction of general anaesthesia and orotracheal intubation
Language: 
English
Abstract: 

BACKGROUND: Etomidate-associated hypnosis has only been studied using standard clinical criteria and raw EEG variables. We conducted a BIS-based investigation of etomidate induction of general anaesthesia. METHODS: Thirty hydroxyzine-premedicated ASA I patients were randomly allocated to receive etomidate 0.2, 0.3, or 0.4 mg kg(-1) intravenously over 30 s. The BIS was continuously recorded. A tourniquet was placed on a lower limb to record purposeful movements and myoclonia. Tracheal intubation was facilitated using rocuronium 0.6 mg kg(-1) when the BIS value was 50. The times to disappearance of the eyelash reflex, to a decrease in the BIS to 50, and to tracheal intubation were compared. The BIS values 30 s following tracheal intubation, and mean arterial pressure (MAP) and heart rate (HR) at all time points were also recorded. RESULTS: The BIS value decreased to 50 for tracheal intubation with no purposeful movement in all but one patient in the 0.2 mg kg(-1) group. There was no difference between the etomidate groups (0.2, 0.3, and 0.4 mg kg(-1)) in regards to time to loss of the eyelash reflex (103 (67), 65 (34), 116 (86) s, P=0.2), or to a decrease in BIS to 50 (135 (81), 82 (36), 150 (84) s, P=0.1). Also, the BIS value 30 s after intubation (41 (10), 37 (4), 37 (4), P=0.4), and plasma etomidate concentrations (161 [29-998], 308 [111-730], 310 [90-869] ng ml(-1), P=0.2) did not differ between groups. The time to loss of the eyelash reflex was 12-140 s shorter than the time to a decrease in BIS to 50 in three patients in each group who received etomidate 0.2 and 0.4 mg kg(-1), and in four patients who received 0.3 mg kg(-1). No awareness was recorded. MAP and HR increases following tracheal intubation were comparable between groups. CONCLUSIONS: Etomidate induction doses do not predict the time for BIS to decrease to 50 as this variable varies markedly following three etomidate dose regimen.

Author(s): 
Lallemand, M.-A.
Lentschener, C.
Mazoit, J.-X.
Bonnichon, P.
Manceau, I.
Ozier, Y.
Item Type: 
Journal Article
Publication Title: 
British Journal of Anaesthesia
Journal Abbreviation: 
Br J Anaesth
Publication Date: 
9/3/2015
Publication Year: 
2003
Pages: 
341-346
Volume: 
91
Issue: 
3
ISSN: 
0007-0912
Library Catalog: 
PubMed
Extra: 
PMID: 12925471

Turabian/Chicago Citation

M.-A. Lallemand, C. Lentschener, J.-X. Mazoit, P. Bonnichon, I. Manceau and Y. Ozier. 9/3/2015. "Bispectral index changes following etomidate induction of general anaesthesia and orotracheal intubation." British Journal of Anaesthesia 91: 3: 341-346.

Wikipedia Citation

<ref> {{Cite journal | doi = | issn = 0007-0912 | volume = 91 | pages = 341-346 | last = Lallemand | first = M.-A. | coauthors = Lentschener, C., Mazoit, J.-X., Bonnichon, P., Manceau, I., Ozier, Y. | title = Bispectral index changes following etomidate induction of general anaesthesia and orotracheal intubation | journal = British Journal of Anaesthesia | date = 9/3/2015 | pmid = | pmc = }} </ref>