Neuromonitoring During Rapid Ventricular Pacing in Patients Undergoing Cerebral Aneurysm Surgery

Study Overview
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Brief Summary
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To evaluate the effect of rapid ventricular pacing on the oxygenation of the brain in patients scheduled for cerebral aneurysm clipping surgery or arteriovenous malformation surgery.

Detailed Description
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Patients scheduled for cerebral aneurysm clipping surgery or arteriovenous malformation surgery(ASA 1to 3 over 18years) receive standard care general anesthesia including central venous line for rapid ventricular pacing technique. A contralateral Foresight sensor is placed on the forehead of the patient at induction. After the craniotomy two micro electrodes(PBtO2 and cerebral blood flow) are placed in the brain and fixated. A subdural strip electrode is placed on the surface of the brain to record the electrical activity. Effect of mild hyperventilation and oxygenation with 100% O2 is evaluated.

Official Title
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Safety of Rapid Ventricular Pacing During Cerebral Aneurysm Surgery by Multimodal Neuromonitoring

Conditions
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Cerebral Arterial Aneurysm, Ventricular Rate Response Pacing

Intervention / Treatment
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* Other: rapid ventricular pacing
* Procedure: Surgery


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: scheduled for cerebral aneurysm surgery or arterial venous malformation American Society of Anesthesiologists classification 1, 2, or 3 Exclusion Criteria: non

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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Design Details

Primary Purpose: Other
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: rapid ventricular pacing<br>Safety of rapid ventricular pacing during neurosurgical procedures | Other: rapid ventricular pacing<br> <br> Procedure: Surgery<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cerebral oxygenation during surgery | Oxygenation of the brain is measured by near-infrared spectroscopy and by evaluation of the brain tissue oxygen pressure by two microelectrodes placed in the brain. | During surgery | 
| Cerebral blood flow during surgery | Thermal diffusion flowmetry measures the local absolute cerebral blood flow | During surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Electrophysiological changes in the brain during surgery | Electro-corticography measures electrophysiological changes in the brain. | During surgery | 
| Effect of ventilation with 100 % oxygen on cerebral parameters after rapid ventricular pacing | Effect of ventilation with 100% oxygen on cerebral blood flow and cerebral tissue oxygenation measured by thermal diffusion flowmetry and brain tissue oxygen pressure measured by microelectrodes placed in the brain in combination with near-infrared spectroscopy, respectively. | Intraoperative ( Start of ventilation at 100% oxygen until bloodgas analyses shows an increase in arterial oxygen pressure.) | 
| Effect of hyperventilation on cerebral parameters after rapid ventricular pacing | Effect of hyperventilation (defined as arterial carbon dioxide pressure between 24 and 32 millimeter mercury) on cerebral blood flow and cerebral tissue oxygenation measured by thermal diffusion flowmetry and brain tissue oxygen pressure measured by microelectrodes placed in the brain in combination with near-infrared spectroscopy, respectively. | Intraoperative (Start of hyperventilation until bloodgas analyses shows an arterial carbon dioxide pressure between 24 and 32 millimetre of mercury.) |