Cardiac Output and Duplex Sonography in Carotid Endarterectomy

Study Overview
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Brief Summary
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The aim of this study is to investigate the differences between the cardiac output and the cerebral blood-flow between a regional anesthesia (RA) and a general anesthesia (GA) in a randomized, controlled, single center study at the Medical University Innsbruck, Department of Anesthesia and Intensive Care Medicine.

Detailed Description
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The investigators will investigate the differences between the cardiac output and the cerebral blood-flow between a regional anesthesia (RA) and a general anesthesia (GA) in a randomized, controlled, single center study at the Medical University Innsbruck, Department of Anesthesia and Intensive Care Medicine. For this purpose patients with the need of a carotid endarterectomy (CEA) will be included and randomized either to the regional anesthesia (RA) or the general anesthesia (GA) group until a patient number of 45 in each group is achieved. The cardiac output and cerebral blood-flow via trans-cranial Doppler (TCD) will be measured at 6 time points: T0 Baseline (after insertion of an arterial line) T1 After induction of anesthesia, but before surgical start T2 Two minutes after clamping the carotid artery T3 Two minutes after shunt insertation of the carotid artery T4 After reperfusion T5 After completion of the skin suture

Official Title
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Cardiac Output and Cerebral Blood-flow During Carotid Endarterectomy in Regional vs. General Anesthesia. A Prospective Randomized Controlled Single Center Study

Conditions
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Carotid Stenosis

Intervention / Treatment
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* Procedure: Regional anesthesia
* Procedure: General anesthesia
* Device: Transcranial Doppler ultrasonography
* Procedure: blood gas analysis
* Procedure: invasive arterial blood pressure measurement
* Procedure: arterial blood gas measurement
* Behavioral: Neurological Control
* Behavioral: NIRS monitoring
* Device: oxygen supply (not invasive 'Vigileo')


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age >= 18 years Elective carotid endarterectomy Signed informed consent Exclusion Criteria: Age under 18 years Missing signed informed 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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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Regional anesthesia (RA)<br>Regional anesthesia (RA) for a carotid endarterectomy Interventions: Regional anesthesia (RA), blood gas analysis, 'Transcranieller Doppler' (Transcranial Doppler ultrasonography), invasive arterial blood pressure measurement, arterial blood gas measurement, neurological control, Near-infrared spectroscopy (NIRS) monitoring, oxygen supply (not invasive 'Vigileo') | Procedure: Regional anesthesia<br>* Regional anesthesia<br>Device: Transcranial Doppler ultrasonography<br>* 6x for 4 hours<br>Procedure: blood gas analysis<br>* 6 x 3 ml blood withdrawal (18 ml) within 4 hours<br>Procedure: invasive arterial blood pressure measurement<br>* before operation, 8 hours, as done in clinical routine<br>Procedure: arterial blood gas measurement<br>* perioperative, 4-6 times within 8 hours, as done in clinical routine<br>Behavioral: Neurological Control<br>* perioperative, 2-3 days, as done in clinical routine<br>Behavioral: NIRS monitoring<br>* perioperative, for 5 hours, as done in clinical routine<br>Device: oxygen supply (not invasive 'Vigileo')<br>* perioperative for 5 hours, as done in clinical routine<br>|
| Other: General anesthesia (GA)<br>General anesthesia (GA) for a carotid endarterectomy Interventions: General anesthesia, blood gas analysis, 'Transcranieller Doppler' (Transcranial Doppler ultrasonography), invasive arterial blood pressure measurement, arterial blood gas measurement, neurological control, NIRS monitoring, oxygen supply (not invasive 'Vigileo') | Procedure: General anesthesia<br>* General anesthesia<br>Device: Transcranial Doppler ultrasonography<br>* 6x for 4 hours<br>Procedure: blood gas analysis<br>* 6 x 3 ml blood withdrawal (18 ml) within 4 hours<br>Procedure: invasive arterial blood pressure measurement<br>* before operation, 8 hours, as done in clinical routine<br>Procedure: arterial blood gas measurement<br>* perioperative, 4-6 times within 8 hours, as done in clinical routine<br>Behavioral: Neurological Control<br>* perioperative, 2-3 days, as done in clinical routine<br>Behavioral: NIRS monitoring<br>* perioperative, for 5 hours, as done in clinical routine<br>Device: oxygen supply (not invasive 'Vigileo')<br>* perioperative for 5 hours, as done in clinical routine<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Influence of anesthetic technique on cardiac output during carotid endarterectomy. | Number of participants: 90 patients Unit of measure: Cardiac index (l/m2) Cardiac output will be measured and compared at the following time points: T0 Baseline (after insertion of an arterial line) T1 After induction of anesthesia, but before surgical start T2 Two minutes after clamping the carotid artery T3 Two minutes after shunt insertation of the carotid artery T4 After reperfusion T5 After completion of the skin suture | Baseline to induction of anesthesia and up to 1 hour after admission to the intermediate care unit | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Influence of anesthetic technique on trans-cranial doppler flow during carotid endarterectomy. | Cerebral blood flow will be measured via trans-cranial Doppler (TCD) and compared at the following time points: T0 Baseline (after insertion of an arterial line) T1 After induction of anesthesia, but before surgical start T2 Two minutes after clamping the carotid artery T3 Two minutes after shunt insertation of the carotid artery T4 After reperfusion T5 After completion of the skin suture | Change of cardiac output from Baseline to induction of anesthesia and up to 1 hour after admission to the intermediate care unit | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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carotid endarterectomy, cardiac output, trans-cranial Doppler, CEA, regional anesthesia, general anesthesia