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Bispectral Index: A Comparison of Bifrontal Montage Agreement

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT04062240
Recruitment Status : Enrolling by invitation
First Posted : August 20, 2019
Last Update Posted : December 10, 2020
Information provided by (Responsible Party):
Matthew J. Ritter, Mayo Clinic

Tracking Information
First Submitted Date August 16, 2019
First Posted Date August 20, 2019
Last Update Posted Date December 10, 2020
Actual Study Start Date November 27, 2019
Estimated Primary Completion Date June 2021   (Final data collection date for primary outcome measure)
Current Primary Outcome Measures
 (submitted: August 16, 2019)
BIS Montage [ Time Frame: 10 minutes where both sensors are recording concurrently ]
Degree of variability between sensors in a bifrontal montage when monitored simultaneously
Original Primary Outcome Measures Same as current
Change History
Current Secondary Outcome Measures
 (submitted: August 16, 2019)
Ketamine [ Time Frame: 10 minutes where both sensors are recording concurrently ]
Degree to which Ketamine may influence BIS values
Original Secondary Outcome Measures Same as current
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
Descriptive Information
Brief Title Bispectral Index: A Comparison of Bifrontal Montage Agreement
Official Title Bispectral Index: A Comparison of Bifrontal Montage Agreement
Brief Summary The researchers are trying to compare the results of two sensors when recorded simultaneously on opposite sides of the forehead.
Detailed 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.
Study Type Observational
Study Design Observational Model: Case-Control
Time Perspective: Prospective
Target Follow-Up Duration Not Provided
Biospecimen Not Provided
Sampling Method Non-Probability Sample
Study Population The study population consists of adult patients undergoing elective cardiac surgery, for whom BIS monitoring will be used.
  • Surgery
  • Bispectral Index
Intervention Device: BIS sensor
BIS sensors will be labeled L and R. The degree of variability between the concurrent use of the sensors will be assessed .
Study Groups/Cohorts Additional BIS sensor
Many providers caring for cardiovascular surgical patients utilizes BIS monitoring to gauge depth of anesthesia. The current practice involves placement of the BIS sensor on the patient's forehead per the manufacturer's recommendation on arrival to the operating room. The intervention in this study will add an additional BIS sensor to the patient's forehead. After syncing the two monitors for time, and ensuring appropriate skin contact and signal quality of both sensors, BIS monitoring will commence. BIS readings will be available every 12 seconds during the duration of the study, yielding up to 240 points of comparison per enrolled patient.
Intervention: Device: BIS sensor
Publications *

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
Recruitment Information
Recruitment Status Enrolling by invitation
Estimated Enrollment
 (submitted: August 16, 2019)
Original Estimated Enrollment Same as current
Estimated Study Completion Date June 2021
Estimated Primary Completion Date June 2021   (Final data collection date for primary outcome measure)
Eligibility Criteria

Inclusion Criteria:

1. Adult patient having elective cardiac surgery

Exclusion Criteria:

  1. Patient refusal.
  2. Pediatric patients.
  3. Emergency procedure.
  4. Patients with known or suspected carotid or cerebrovascular disease.
  5. Patients with prior stroke.
  6. Skin condition or anatomy preventing proper sensor placement.
Sexes Eligible for Study: All
Ages 18 Years and older   (Adult, Older Adult)
Accepts Healthy Volunteers No
Contacts Contact information is only displayed when the study is recruiting subjects
Listed Location Countries United States
Removed Location Countries  
Administrative Information
NCT Number NCT04062240
Other Study ID Numbers 19-000568
Has Data Monitoring Committee Not Provided
U.S. FDA-regulated Product
Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: Yes
Product Manufactured in and Exported from the U.S.: Yes
IPD Sharing Statement
Plan to Share IPD: No
Responsible Party Matthew J. Ritter, Mayo Clinic
Study Sponsor Mayo Clinic
Collaborators Not Provided
Principal Investigator: Matthew Ritter, MD Mayo Clinic
PRS Account Mayo Clinic
Verification Date December 2020