Efficacy and Safety of Short-term Postoperative Anticoagulant Therapy to Prevente Thrombosis in Arterovenous Fistula

Study Overview
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Brief Summary
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Many guidelines at home and abroad advocate that arteriovenous fistula should be the first choice of permanent vascular access, but it is easy to form thrombus in a short time after arteriovenous fistula molding, resulting in internal fistula stenosis or occlusion. In this study, the investigators plan to screen the patients with arteriovenous fistula in the blood purification center of our hospital. Through the study design of random grouping and open label, the investigators will discuss the use of low molecular weight heparin or warfarin to prevent thrombosis in a short period of time after arteriovenous fistula operation. According to the research results, the investigators will understand efficacy and safety of short-term postoperative anticoagulant therapy to prevente thrombosis in arterovenous fistula.

Official Title
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Efficacy and Safety of Short-term Postoperative Anticoagulant Therapy to Prevente Thrombosis in Arterovenous Fistula

Conditions
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Thrombosis

Intervention / Treatment
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* Drug: Low molecular weight heparin
* Other: non anticoagulant therapy group


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: the participants were treated with autogenous arteriovenous fistula, reconstruction and balloon dilatation; stable health, compliant with treatment, and active following treatment. Exclusion Criteria. age > 85 years old; history of blood system diseases; history of familial and hereditary bleeding diseases; important complications affecting the coagulation system, such as liver diseases; abnormal coagulation function and active bleeding; history of intracranial and digestive tract bleeding, obvious skin stasis; complications, such as surgery and tumor, which significantly increase the risk of bleeding; no subjective will.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

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
Interventional Model Description: we plan to recruite the patients with arteriovenous fistula in the blood purification center of our hospital. After recruitment, the patients were randomly assigned to anticoagulant therapy group or non anticoagulant therapy group. anticoagulant therapy group: during hospitalization, patients began to use low molecular weight heparin subcutaneously after arteriovenous fistula operation, once or twice a day, 4000iu-8000iu a day. After discharge, the patients took warfarin sodium tablets orally, 1.25mg on dialysis day, 2.5mg on non dialysis day, for a total course of 4 weeks. non anticoagulant therapy group: no anticoagulant was used after operation, but both groups could take antiplatelet drugs.Efficacy and safety of short-term postoperative anticoagulant therapy to prevente thrombosis were evaluated.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: anticoagulant therapy group<br>during hospitalization, patients began to use low molecular weight heparin subcutaneously after arteriovenous fistula operation, once or twice a day, 4000iu-8000iu a day. After discharge, the patients took warfarin sodium tablets orally, 1.25mg on dialysis day, 2.5mg on non dialysis day, for a total course of 4 weeks. | Drug: Low molecular weight heparin<br>* patients began to use low molecular weight heparin or warfarin sodium tablets.<br>* Other names: warfarin sodium tablets;|
| Other: non anticoagulant therapy group<br>no anticoagulant was used after operation, but both groups could take antiplatelet drugs. | Other: non anticoagulant therapy group<br>* no anticoagulant was used after operation.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Blood flow of arteriovenous fistula | Blood flow of arteriovenous fistula during hemodialysis from 6 months after operation | up to 6 months | 
| arteriovenous fistula dysfunction or occlusion | The proportion of arteriovenous fistula dysfunction or occlusion | up to 6 months | 
| Active bleeding events | such as,bleeding of surgical wound, intracranial, digestive tract and urinary tract, ecchymosis and ecchymosis of skin. | up to 6 months | 
| arteriovenous fistula dysfunction or occlusion | The time of arteriovenous fistula dysfunction or occlusion | up to 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| coagulation index | Change of coagulation index | up to 6 months | 
| Platelet | Changes of platelet indexes | up to 6 months | 
| Number of hospitalization | Number of hospitalization due to arteriovenous fistula thrombosis. | up to 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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manitenance hemodialysis patients, arteriovenous fistula operation, Thrombosis, anticoagulant therapy, Efficacy, safety