Intraoperative M-Entropy Measurements
|Study Design:||Observational Model: Case-Only
Time Perspective: Prospective
|Official Title:||Same-patient Reproducibility of Intraoperative M-Entropy Measurements|
- The investigators 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 ]
|Study Start Date:||September 2007|
|Study Completion Date:||April 2009|
|Primary Completion Date:||June 2008 (Final data collection date for primary outcome measure)|
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: study cases
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)
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.
The 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.
Please refer to this study by its ClinicalTrials.gov identifier: NCT00599066
|United States, Oklahoma|
|OU MEDICAL CENTER, Presbyterian Tower, OR|
|Oklahoma City, Oklahoma, United States, 73104|
|Principal Investigator:||Mehemet Ozcan, MD||The University of Oklahoma Health Sciences Center, Department of Anesthesiology|