Use of Brain Oxygen Tension Level and Cleaved-tau Protein to Detect Vasospasm After SAH

Study Overview
=================
Brief Summary
-----------------
The purpose of this study is to investigate if brain oxygen levels, levels of a specific protein in the cerebrospinal fluid and blood (Cleaved-tau protein), and brain blood flow can predict spasm of brain blood vessels after bleeding in the brain from a ruptured aneurysm.

Detailed Description
-----------------
Rupture of a cerebral aneurysm causes subarachnoid hemorrhage (SAH). Blood in the subarachnoid space of the brain can cause irritation of the cerebral blood vessels, leading to constriction of these vessels, a phenomenon known.as vasospasm. Cerebral vasospasm can cause stroke and possibly death. Of all the patients with SAH, approximately 20-40% will suffer from clinical vasospasm and more than 60% of those patients will never get back to their previous functional status. Tools to identify early vasospasm and thus early treatment could greatly decrease the morbidity and mortality following SAH. Cleaved tau protein is a neuronal marker that has been detected in blood and CSF of stroke patients early in its time course. Since vasospasm can lead to stroke, the purpose of this project is to determine whether increase in cleaved tau protein in blood and/or CSF can predict early stroke from vasospasm. Changes in brain oxygen tension measured by a brain tissue oxygen monitor and cerebral blood flow measured by CT perfusion will be correlated with cleaved tau protein levels and clinical status. Utilizing statistical analysis the levels of Cleaved tau protein, brain oxygen and blood flow during hospitalization will be correlated with patient outcome. Through this study we hope to identify increase in cleaved tau protein and decrease in cerebral blood flow and oxygenation as predictors of early vasospasm. Early detection and treatment of vasospasm could decrease the stroke rate in SAH patients and therefore be of great benefit to society.

Official Title
-----------------
Brain Oxygen Tension Level, Cerebral Perfusion and Cleaved-tau Protein for Detection of Cerebral Vasospasm and Independent Predictor of Poor Outcome After Aneurysmal Subarachnoid Hemorrhage

Conditions
-----------------
Subarachnoid Hemorrhage, Cerebral Vasospasm

Intervention / Treatment
-----------------
* Device: Licox Brain Oxygen Monitor
* Other: CSF
* Other: Whole blood


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Patients with subarachnoid hemorrhage Patients with external ventricular drains Exclusion Criteria: Patients in whom consent is not attainable

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Hemorrhage<br>Patients having experienced subarachnoid hemorrhage and have in place a ventriculostomy | Device: Licox Brain Oxygen Monitor<br>* use of data from brain oxygen monitor for analysis<br>Other: CSF<br>* analysis of CSF for cleaved tau protein<br>Other: Whole blood<br>* Analysis of whole blood for cleaved-tau protein<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in brain oxygen tension level, cerebral blood flow, and cleaved tau protein levels in correlation to cerebral vasospasm |  | The first 14 days after subarachnoid hemorrhage | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Clinical outcome score correlated to changes in brain oxygen tension level, cerebral blood flow, and cleaved tau protein levels |  | Three months after subarachnoid hemorrhage | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Subarachnoid hemorrhage, Cerebral Vasospasm, Cleaved-tau protein, Brain oxygen tension level