Bispectral Index: A Comparison of Bifrontal Montage Agreement

Surgery Clinical Trial

Official title: Bispectral Index: A Comparison of Bifrontal Montage Agreement

Status Completed

Clinical Trial Summary

The researchers are trying to compare the results of two sensors when recorded simultaneously on opposite sides of the forehead.

Clinical Trial Description

Bispectral Index (BIS) monitors are FDA approved to gauge depth of sedation by analyzing segments of electroencephalogram (EEG) waves. The BIS monitor utilizes a proprietary algorithm to process the EEG information second by second, and outputs a number (0-100) that corresponds with a patient's level of consciousness. A level of 0 indicates no EEG activity; a level of 100 indicates awake EEG activity. Several studies demonstrated that BIS monitors may not be useful in paralyzed patients, as patients who were paralyzed and not sedated unexpectedly showed a large decrease in their BIS values following administration paralytic medications. Vivien et al found BIS values dropped an average of 24 points in already sedated patients when the patients were given paralytics. In the same year, Messner and colleagues paralyzed non-sedated volunteers and found a dramatic drop in BIS values until paralysis wore off or was reversed. Schuller et al repeated the Messner experiment and found similar results with 18 of 20 non-sedated volunteer's BIS values dropping to levels expected of patients who were sedated. These results suggest that BIS monitors are integrating electromyography (EMG) data into its algorithm to derive a BIS value. Our hypothesis is that a BIS monitor commenced after paralysis, thereby lacking exposure to any "awake" EMG activity, will result in a cleaner data set and more accurate representation of a patient's level of sedation. Studying in this manner will require the subject to wear two BIS sensors in a frontal montage. The manufacturer of the sensors gives no guidance as to which side of the forehead an individual sensor is placed, and no studies demonstrate BIS validity with the use of concurrent sensors. The purpose of the present investigation is to assess the measurement difference and variability associated with use of concurrent bifrontal BIS sensors. The data obtained will be used as a framework for a future study related to the use of paralytics and BIS monitoring. ;

Related Conditions & MeSH terms

• Bispectral Index
• Surgery

• NCT number: NCT04062240
• Study type: Observational
• Source: Mayo Clinic
• Status: Completed
• Start date: November 27, 2019
• Completion date: October 1, 2021