Hypoxic Preconditioning on Patients

Study Overview
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Brief Summary
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The purpose of this study is to study the effects of intermittent whole-body hypoxic preconditioning on patients with carotid artery stenosis.

Official Title
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The Effects of Intermittent Whole-body Hypoxic Preconditioning on Patients With Carotid Artery Stenosis

Conditions
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Hypoxic Preconditioning, Carotid Artery Stenosis, Ischemic Cerebrovascular Disease

Intervention / Treatment
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* Procedure: Mild Hypoxia Preconditioning
* Procedure: Sham preconditioning


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Informed written consent from the patient. Han nationality, age >18 years. Carotid artery stenosis on at least one side, measuring more than 70% by ultrasonic detection and requiring carotid artery stenting or a carotid endarterectomy. Long-term residence at an altitude of <100 m (the altitude of Tianjin is 2-5 m). Not having been to an altitude ≥1500 m in two years. Exclusion Criteria: Planned vessel sacrifice as the primary modality for ischemic cerebrovascular treatment. Systemic blood disease before intervention. Regular physical activity exercise: frequency >1 time/week, duration >20 min. History of brain disease or history of stroke or transient ischemic attack within the previous six months. History of heart, liver, kidney or lung disease. History of hypertension and poor blood pressure control, with blood pressure >160/90 mmHg. Pregnancy.

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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Mild hypoxia preconditioning<br>Patients will be treated with mild hypoxia (Note: The oxygen concentration decreased from 20% to 18%, and keeping at 18%) before surgery. | Procedure: Mild Hypoxia Preconditioning<br>* Patients will be treated with mild hypoxia ( Note: The oxygen concentration decreased from 20% to 18%, and keeping at 18%)×7 days，twice a day in the morning and in the afternoon before surgery.<br>|
| Sham Comparator: Sham preconditioning<br>Patients will be treated with sham preconditioning (oxygen concentration: 21％) before surgery. | Procedure: Sham preconditioning<br>* Patients will be treated with sham preconditioning (oxygen concentration: 21％) ×7 days，twice a day in the morning and in the afternoon before surgery.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Respiratory rate |  | Before, during and 5 min after the intervention. | 
| Heart rate |  | Before, during and 5 min after the intervention. | 
| Systolic blood pressure |  | Before, during and 5 min after the intervention. | 
| Arterial blood oxygen saturation |  | Before, during and 5 min after the intervention. | 
| Hemoglobin content |  | On admission, and at the 1st day after surgery. | 
| Hypoxia inducible factor-1α |  | On admission, and at the 1st day after surgery. | 
| Erythropoietin |  | On admission, and at the 1st day after surgery. | 
| Vascular endothelial growth factor |  | On admission, and at the 1st day after surgery. | 
| Neuron-specific enolase |  | On admission, and at the 1st day after surgery. | 
| S100β protein |  | On admission, and at the 1st day after surgery. | 
| Brain-derived neurotrophic factor |  | On admission, and at the 1st day after surgery. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Serum aspartate transaminase |  | On admission, and at the 1st day after surgery. | 
| Serum alanine aminotransferase |  | On admission, and at the 1st day after surgery. | 
| Serum creatinine |  | On admission, and at the 1st day after surgery. | 
| Blood urea nitrogen |  | On admission, and at the 1st day after surgery. | 
| The incidence of adverse events |  | During the intervention. | 
| Average length of hospital stay |  | Through study completion, an average of 3 months. | 
| Postoperative complications |  | Through study completion, an average of 3 months. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hypoxic preconditioning, Carotid artery stenosis, Ischemic cerebrovascular disease