Oxygen Concentration and Recovery After Carotid Endarterectomy

Study Overview
=================
Brief Summary
-----------------
This study evaluates effects of high inspiratory oxygen on cerebral tissue oxygenation and patient recovery after carotid endarterectomy. Two group of patient undergoing to carotid with total intravenous anaesthesia will receive either 35% inspired oxygen or 100% oxygen.

Detailed Description
-----------------
High inspired oxygen concentration may reduce brain hypoxia in the patients undergoing carotid endarterectomy with total intravenous anaesthesia. However, there are some studies suggesting that high inspired oxygen concentration may induce cerebral vasoconstriction. This study was performed to measure the influence of fraction of inspired oxygen (FiO2) on the regional tissue oxygenation in the patients undergoing carotid endarterectomy with total intravenous anaesthesia. The INVOS 5100B monitor was used for regional cerebral oxygen saturation (rSO2) measurement from operative and nonoperative side, and INVOS Analytics Tool (Covidien) for area under curve (AUC) calculations. A bispectral index and invasive blood pressure monitoring were used in all patients.

Official Title
-----------------
Effects of High Inspiratory Oxygen on Cerebral Tissue Oxygenation and Patient Recovery After Carotid Endarterectomy

Conditions
-----------------
Hypoxia-Ischemia, Brain, Ischemia, Vertebral Artery, Artery Stenosis, Carotid

Intervention / Treatment
-----------------
* Procedure: Oxygen concentration


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: patient undergoing surgery (carotid endarterectomy) Exclusion Criteria: decompensated and uncontrolled respiratory and cardiac disease, myocardial infarction suffered in the last 6 months, cerebrovascular infarction, coagulopathy, anaphylaxis to drugs

Ages Eligible for Study
-----------------
Minimum Age: 40 Years

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

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

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

Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: 35% O2<br>Patient receiving 35% O2 during carotid endarterectomy, Intervention - oxygen concentration | Procedure: Oxygen concentration<br>* Shunting, raising concentration of O2 because of improving regional cerebral oxygen saturation (rSO2), keeping blood pressure above 120-130 mmHg, positive end expiratory pressure (PEEP)<br>|
| Active Comparator: 100% O2<br>Patient receiving 100% O2 during carotid endarterectomy, Intervention - oxygen concentration | Procedure: Oxygen concentration<br>* Shunting, raising concentration of O2 because of improving regional cerebral oxygen saturation (rSO2), keeping blood pressure above 120-130 mmHg, positive end expiratory pressure (PEEP)<br>|

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

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Area under curve of regional cerebral oxygen saturation (rSO2) curve | Intraoperative high oxygen concentrations may reduce intensity of tissue hypoxic episodes during carotid endarterectomy in total intravenous anesthesia (TIVA). The INVOS 5100B monitor was used for regional cerebral oxygen saturation (rSO2) measurement from operative and nonoperative side, and INVOS Analytics Tool (Covidien) for Area under curve (AUC) calculations. Data were analyzed using two sided T-test and Fisher exact test. A P<0.05 was considered as statistically significant Postoperative follow up in large patient's group is necessary to confirm its impact on patients' outcome. | During surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Early neurologic recovery, TIA or brain ischemia | Postoperative patient follow up by clinical signs or CT scan confirmation | Till 7 days after surgery | 
| Intensive Care Unit admission, Death |  | Till 7 days after surgery | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Normobaric hyperoxia, Cerebral oxygenation, Near-infrared spectroscopy, Carotid endarterectomy, TIVA