Antiaggregation in Primary Prevention of Vascular Access for Hemodialysis

Study Overview
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Brief Summary
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This is a prospective study consisting in testing whether systematic use of aspirin is beneficial for primary prevention of vascular access for hemodialysis attested by doppler ultrasound exam. The investigators will study aspirin resistance in the population of patients undergoing hemodialysis. The investigators will test sensibility of resistant patients to aspirin dose escalation. PFA-100 is the biologic test used in this study to define aspirin resistance.

Detailed Description
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Three groups of dialysed patients will be included in this study. The first is the placebo group, the second is the aspirin group fixed dose and the last group includes patients receiving a dose of aspirin titrated by the result of PFA-100. At the end of this study the investigators will be able to identify whether systematic antiaggregation is suitable for a vascular access for hemodialysis. The investigators will also conclude which is better for patients fixed dose or aspirin dose escalation determined by the result of PFA-100. The study will analyse the prevalence of aspirin resistant patients in this particular population of dialysed patients.

Official Title
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a Comparative Study of Aspirin Either at Fixed Dose or at a Dose Titrated by Platlet Function Analyzer(PFA-100) vs Placebo in Primary Prevention of Vascular Access for Hemodialysis

Conditions
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Thrombosis

Intervention / Treatment
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* Drug: aspirin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: dialysed patients vascular access aged less than one year no serious complication of the vascular access previously such as hemorrhagic complication and tight stenosis Exclusion Criteria: pregnant and breastfeeding women patients receiving at baseline other antiaggregant or anticoagulant patient not allowed to be treated by aspirin systolic blood pressure> 200 mmhg diastolic blood pressure>115 mmhg liver failure
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: Factorial Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: aspirn fixed dose<br>patients of this arm will receive 100 mg of aspirin daily.over the period of follow up we will detect all thromboembolic events. | Drug: aspirin<br> <br> |
| Placebo Comparator: aspirin dose titrated with PFA-100<br>patients of this arm will receive 100 mg of aspirin daily.this dose will be multiplied whenever the PFA-100 is not suitable.once the time of occlusion is correct ,we will keep the same dose of aspirin and continue monitoring the PFA-100 durin the follow up period. | Drug: aspirin<br> <br> |
| No Intervention: placebo arm<br>in this group of patients we will just supervise thromboembolic events of the vascular access. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| number of fistula thrombosis in patients receiving a dose of aspirin titrated by the result of PFA-100 compared to placebo and fixed dose aspirin | patients undergoing hemodialysis via native fistula will receive either placebo or aspirin titrated dose by the PFA-100 or aspirin fixed dose to prevent thrombosis of the access .the follow up period will be fixed at 1 year and all thromboembolic complications of the access will be noted | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| number of aspirin resistant patients even to aspirin escalation dose titrated by PFA-100 in the population of dialysed patients. |  | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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vascular access, hemodialysis, aspirin resistance, PFA-100