Bilateral Bispectral Index (BIS) Study

Study Overview
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Brief Summary
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The purpose of this study is to assess real time changes in raw and processed EEG in relation to the clinical and radiological evidence of cerebral vasospasm.

Detailed Description
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Subarachnoid hemorrhage (SAH) is a prevalent and morbid condition (45%-30 day mortality). One of the major causes of reduced cerebral blood flow (CBF) after initial SAH is cerebral vasospasm. Early treatment of cerebral vasospasm (< 2 hr) is necessary for improved neurologic outcome. Hence, there is significant interest in development of a monitor. The most common bedside diagnostic tool is Transcranial Doppler (TCD) which is controversial given its low sensitivity and specificity. TCD is not a continuous monitor and is user dependent. Many centers rely on Cerebral Angiography for diagnosis of vasospasm; however angiographic spasm does not correlate with outcome. EEG can detect changes in cerebral blood flow which precede clinical decline but is technically difficult to perform and not practical for continuous monitoring. Processed EEG monitors have become somewhat popular in the operating setting for assessment of depth of anesthesia. The recent introduction of bilateral 4 channel disposable probes presents to opportunity to use EEG as a non-invasive continuous monitor for vasospasm. We propose a prospective observational study to assess real time changes in raw and processed EEG which we will correlate with clinical and radiologic evidence of vasospasm. Our primary clinical endpoint will be the determination of delayed cerebral ischemia. This modality could prove to be a significant clinical advantage for patients suffering from SAH.

Official Title
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Real Time Monitoring for Cerebral Vasospasm Using Bilateral Processed Electroencephalogram (EEG)

Conditions
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Cerebral Vasospasm, Delayed Cerebral Ischemia, Subarachnoid Hemorrhage

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult men or women of any age and ethnicity within 48 hours of subarachnoid hemorrhage (SAH) Exclusion Criteria: Age < 18 years Greater than 48 hours past the initial hemorrhage Previous history of stroke of any etiology Inability to consent for themselves or have a proxy to consent for them (implied consent)

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 |
| --- | --- |
| EEG and Cerebral Vasospasm<br>Cerebral Vasospasm and role of BIS vista monitor in Subarachnoid Hemorrhage (SAH) patients | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Detection of delayed cerebral ischemia (DCI) utilizing Bispectral Index (BIS) |  | 10 days stay at the NSICU | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| BIS correlation with angiography and transcranial doppler flow for detection of cerebral vasospasm |  | 10 days stay at the NSICU | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Cerebral vasospasm, delayed cerebral ischemia (DCI), subarachnoid hemorrhage (SAH) patients