OSA as a Remote Ischemic Preconditioning in Vascular Surgery

Study Overview
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Brief Summary
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Ischemia and reperfusion (I/R) injury during abdominal aortic aneurysm (AAA) repair is inevitable and may lead to postoperative multi-organ failure. Remote ischemic preconditioning (short periods of ischemia in anticipation of longer period of ischemia) may act protectively against ischemia. Studies of ischemic preconditioning in patients with AAA are conflicting. Obstructive sleep apnea (OSA) is a sleep disordered breathing syndrome which may have a protective effect against ischemia. The investigators hypothesize that I/R injury will be less pronounced in patients who have OSA and that the extent of I/R injury will inversely correlate with OSA severity. Accordingly, the aim of this study is to compare postoperative complications and markers of I/R in patients undergoing elective AAA repair who do and do not have OSA.

Detailed Description
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Patients. Consecutive patients scheduled for elective aortobifemoral bypass (AAA and Leriche syndrome patients) will be recruited for this prospective, observational study. Polygraphy (PG). PG measurements will be done two nights before surgery using the Embletta system (Embla - Embletta MPR PG Sleep Data Recording System). STOP-BANG, Epworth questionnaire. Both questionnaires will be done the same day as polygraphy Cardiovascular complications will be assessed from the first 30 post-operative days Pulmonary complications will be assessed from the first 30 post-operative days Specific markers of I/R. T0 - before anesthesia induction T1 - 3 hrs after aorta de-clamping T2 - 12 hrs after aorta de-clamping T3 - 24 hrs after aorta de-clamping T4 - on the fifth post-operative day

Official Title
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Obstructive Sleep Apnea as a Remote Ischemic Preconditioning in Patients Scheduled for Aorto-bifemoral Bypass Surgery

Conditions
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Vascular Aneurysm, Obstructive Sleep Apnea, Ischemia Reperfusion Injury

Intervention / Treatment
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* Procedure: aorto-bifemoral bypass surgery


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients scheduled for elective aorto-bifemoral bypass (AAA and Leriche syndrome patients) Exclusion Criteria: emergent surgery aorto-bifemoral bypass using deep vein graft re-operations known OSA with CPAP treatment

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 |
| --- | --- |
| Obstructive Sleep Apnea<br>Pacient with OSA (AHI≥5) undergoing aorto-bifemoral bypass | Procedure: aorto-bifemoral bypass surgery<br>* aorto-bifemoral bypass surgery (Leriche syndrom, elective AAA repair)<br>|
| Without Obstructive Sleep Apnea<br>Patinets without OSA undergoing aorto-bifemoral bypass | Procedure: aorto-bifemoral bypass surgery<br>* aorto-bifemoral bypass surgery (Leriche syndrom, elective AAA repair)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of I/R injury markers | Plasma Total Antioxidant Capacity and Reactive Oxygen Species Concentration | T0 - before anesthesia induction; T1 - 3 hrs after aorta de-clamping; T2 - 12 hrs after aorta de-clamping; T3 - 24 hrs after aorta de-clamping; T4 - on the fifth post-operative day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| post-operative complications | cardiovascular and pulmonary post-operative complications | up to 30 post-operative days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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remote preconditioning