Intraoperative M-Entropy Measurements - Full Text View

Purpose

The purpose of this study is to learn more about an Entropy monitor that your anesthesiologist will be using.

Condition	Intervention
General Anesthesia	Device: Entropy monitor (Datex-Ohmeda S/5 EntropyTM Module)

Study Type:	Interventional
Study Design:	Endpoint Classification: Safety/Efficacy Study Intervention Model: Single Group Assignment Masking: Open Label Primary Purpose: Supportive Care
Official Title:	Same-Patient Reproducibility of Intraoperative M-Entropy Measurements

Further study details as provided by University of Oklahoma:

Primary Outcome Measures:

We hypothesize that simultaneous M-Entropy measurements from the left and right side of the forehead of a person do not differ during general anesthesia. [ Time Frame: 1 year ] [ Designated as safety issue: Yes ]

Enrollment:	22
Study Start Date:	September 2007
Study Completion Date:	April 2009
Primary Completion Date:	June 2008 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
Experimental: 1 Application of a second M-Entropy probe on the forehead of the patient; at the end the patient will have 2 probes on the forehead, one in the right and one in the left.	Device: Entropy monitor (Datex-Ohmeda S/5 EntropyTM Module) Application of a second M-Entropy probe on the forehead of the patient, which will happen in the OR along with the application of other monitors immediately before induction of general anesthesia. Other Name: M-entropy module (Datex-Ohmeda S/5 EntropyTM Module)

Detailed Description:

Depth of anesthesia monitors are increasingly used in clinical anesthesia practice. Bispectral Index (BIS) and M-Entropy are examples to these devices, both of which are available at our institution. Both BIS and M-Entropy use a unilateral, single channel of EEG to derive a number indicating the anesthetic depth. These devices have similar disposable skin probes that can be applied on either side of the forehead. Since the depth of anesthesia for an individual is the same over the whole brain cortex at a given point in time, BIS numbers obtained over the left and right side of the forehead should agree. The same should be true for M-Entropy as well.

A recent study, however, showed that two separate BIS probes, applied over the left and right forehead of the same patient at the same time, can give significantly different numbers. This has not been studied for M-Entropy. BIS and M-Entropy use different mathematical algorithms that process the raw EEG signal to compute a numeric value. Therefore, it is possible that M-Entropy may show different results in a similar study setup.

Our aim is to investigate the same-patient reproducibility of M-Entropy by monitoring and recording Entropy variables over both the left and the right side of the forehead of patients under general anesthesia.

Eligibility

Ages Eligible for Study:	18 Years to 90 Years
Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	No

Criteria

Inclusion Criteria:

Patients scheduled to have surgery under general anesthesia, with a minimum of 60 minutes expected duration.

Exclusion Criteria:

Non English speaker
Patients younger than 18 years of age

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00599066

Locations

United States, Oklahoma
OU MEDICAL CENTER, Presbyterian Tower, OR
Oklahoma City, Oklahoma, United States, 73104

Sponsors and Collaborators

University of Oklahoma

Investigators

Principal Investigator:

Mehemet Ozcan, MD

The University of Oklahoma Health Sciences Center, Department of Anesthesiology

More Information

Publications:

Niedhart DJ, Kaiser HA, Jacobsohn E, Hantler CB, Evers AS, Avidan MS. Intrapatient reproducibility of the BISxp monitor. Anesthesiology. 2006 Feb;104(2):242-8.

Ozcan MS, Gravenstein D. The presence of working memory without explicit recall in a critically ill patient. Anesth Analg. 2004 Feb;98(2):469-70, table of contents.

Responsible Party:	Mehemet Ozcan, MD, The University of Oklahoma Health Sciences Center, Department of Anesthesiology
ClinicalTrials.gov Identifier:	NCT00599066 History of Changes
Other Study ID Numbers:	IRB No: 13577
Study First Received:	December 20, 2007
Last Updated:	July 9, 2009
Health Authority:	United States: Institutional Review Board

Keywords provided by University of Oklahoma:

M-Entropy

ClinicalTrials.gov processed this record on May 16, 2013