BIS and Entropy in Deep Brain Simulation

Study Overview
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Brief Summary
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The main objective of the study is to determine whether depth of anesthesia (DOA) monitoring such as Bispectral Index (BIS) and entropy are accurate in patients with neuro-psychological conditions such as Parkinson's disease by comparing these monitoring with standard clinical monitoring like heart rate, blood pressure and respiratory rate.

Detailed Description
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Deep brain simulation (DBS) is an increasingly popular treatment for movement and psychiatric disorders such as Parkinson's disease and dystonia. These patients are quite sensitive to anesthetics and use of depth of anesthesia monitors are often needed to titrate the anesthetics. The calibration of BIS and entropy monitors has been done only on subjects with no neurological diseases. The investigators plan to record BIS and entropy readings during general anesthesia (GA) for the internalization of DBS electrodes. This would be useful as there are very few studies in this subset of patients with regards to DOA monitoring. Ashraf argued that the EEG may be altered under these circumstances and hence produce invalid BIS readings. Pemberton et al. studied patients undergoing tumour surgery using a sleep- awake-sleep anaesthesia technique. They found a poor correlation between BIS values and the observer's assessment of anesthesia level, suggesting that BIS is not a reliable tool for patients with brain abnormalities. The purpose of this study was to investigate whether BIS and entropy are helpful in titrating DOA in patients undergoing neurosurgical procedures or suffering from neurological diseases as they were frequently excluded from validation studies of the BIS monitoring device.

Official Title
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Comparison of Bispectral Index and Entropy Monitoring in Patients Undergoing Internalization of Deep Brain Simulation

Conditions
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Movement Disorders, Depth of Anesthesia Monitors

Intervention / Treatment
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* Device: BIS monitor
* Device: Entropy monitor


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients older than 18 years of age scheduled for elective internalisation of DBS electrodes under general anesthesia. Exclusion Criteria: lack of informed consent language barrier those that are transferred to an intensive care unit postoperatively.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| BIS and Entropy monitoring<br>Depth of anesthesia monitoring (BIS and entropy) are compared with standard clinical monitoring in patients with deep brain stimulators inserted at internalization whilst they are having a general anesthesia. | Device: BIS monitor<br>* Both types of depth of anesthesia monitoring (BIS and entropy- electrodes) are applied on patients together with standard monitoring (heart rate, blood pressure, respiratory rate). The two different types of depth of anesthesia monitoring are then compared.<br>Device: Entropy monitor<br>* Both types of depth of anesthesia monitoring (BIS and entropy- electrodes) are applied on patients together with standard monitoring (heart rate, blood pressure, respiratory rate). The two different types of depth of anesthesia<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation Between Bispectral (BIS) and Response Entropy (RE) Indices | The trends of Bispectral (BIS) and Response entropy (RE) at different study time points. Bispectral (BIS) and Response entropy (RE) values range from 0 (absence of brain activity) to 100 (fully awake state). Values below 40 indicate deep anesthesia, values from 40 to 60 optimal and above 60 but below 90 inadequate anesthesia. | One day | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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depth of anesthesia monitors, deep brain stimulation