Table of Contents
ISRN Pain
Volume 2013, Article ID 583920, 8 pages
http://dx.doi.org/10.1155/2013/583920
Clinical Study

Changes in the Bispectral Index in Response to Experimental Noxious Stimuli in Adults under General Anesthesia

1School of Nursing, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, QC, Canada J1K 2R1
2Sherbrooke University Hospital (CHUS), Sherbrooke, QC, Canada J1H 1P8
3School of Rehabilitation, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, QC, Canada J1K 2R1
4Centre de Recherche Clinique Étienne-Le Bel du Centre Hospitalier Universitaire de Sherbrooke (CHUS), Sherbrooke, QC, Canada J1H 5N4
5School of Nursing, McGill University, Montreal, QC, Canada H3A 0G4
6Center for Nursing Research and Lady Davis Institute, Jewish General Hospital, Montreal, QC, Canada H3T 1E2
7Department of Anesthesiology, School of Medicine, University of Montreal, Montreal, QC, Canada H3C 3J7
8Department of Anesthesiology, School of Medicine, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, QC, Canada J1K 2R1

Received 16 May 2013; Accepted 25 June 2013

Academic Editors: T. A. Ignatowski, M. Tsuruoka, and T. Warbrick

Copyright © 2013 Robin Marie Coleman et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Objective. Pain assessment is a major challenge in nonverbal patients in the intensive care unit (ICU). Recent studies suggest a relationship between the Bispectral Index (BIS) and nociceptive stimuli. This study was designed to examine changes in BIS in response to experimental noxious stimuli. Methods. Thirty participants under general anesthesia were in this quasiexperimental, within subject, pre- and poststudy. In the operating room (OR), BIS was monitored during moderate and severe noxious stimuli, induced by a thermal probe on the participants’ forearm, after induction of general anesthesia, prior to surgery. Results. Significant increases in BIS occurred during moderate (increase from 35.00 to 40.00, ) and severe noxious stimuli (increase from 37.67 to 40.00, ). ROC showed a sensitivity (Se) of 40.0% and a specificity (Sp) of 73.3% at a BIS value > 45, in distinguishing a moderate from a severe noxious stimuli. Conclusion. BIS increased in response to moderate and severe noxious stimuli. The Se and Sp of the BIS did not support the use of the BIS for distinction of different pain intensities in the context of deep sedation in the OR. However, the results justify further studies in more lightly sedated patients such as those in the ICU.