The Outcomes of Arteriovenous Fistula Cannulated From Different Direction.

Study Overview
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Brief Summary
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The investigators hypothesis that aneurysms and stenoses will be decreased if the direction of inserted arterial needle were same as the direction of blood flow, when compared to the opposite direction puncture.

Detailed Description
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Native arteriovenous fistula (AVF) is the preferred access for hemodialysis, and cannulation technique is very important factors affect the outcomes of AVF. Rope-ladder cannulation is one kind of the standard puncture techniques which is used commonly in maintenance hemodialysis (MHD) patients. There are many complications for rope-ladder cannulation, such as venous aneurysm and vascular stenosis, which may induce AVF dysfunction. For the venous outflow way, there always be aneurysm followed by stenoses at the sites of needle connected with the arterial line in rope-ladder cannulation patients. The investigators hypothesis that the directions of inserted arterial needles should affect the AVF outcomes. The present prospective study will compare the outcomes of AVF between the puncture direction at arterial needle sites same as blood flow and opposite to blood flow.

Official Title
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The Outcomes of Arteriovenous Fistula (AVF) Cannulated From Different Direction in Maintenance Hemodialysis Patients.

Conditions
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Arteriovenous Fistula

Intervention / Treatment
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* Other: Same direction cannulation
* Other: Opposite direction cannulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: MHD patients with autogenous AVF. Newly setup AVF in 3 months. Fore- or Upper arm AVF. Flow of >800ml/min detected by using the ultrasound dilution technique. Exclusion Criteria: AVF after neoplasty. Arteriovenous grafts. Anticipated live time less than one year. Patients whose concurrent illnesses, disability, or geographical residence would hamper attendance at required study visit.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Same direction cannulation<br>The inserted direction of arterial needle is same as the direction of blood flow. | Other: Same direction cannulation<br>* The puncture direction of the arterial needle is same as the blood flow in every hemodialysis session.<br>|
| Active Comparator: Opposite direction cannulation<br>The inserted direction of arterial needle is opposite to the direction of blood flow. | Other: Opposite direction cannulation<br>* The puncture direction of the arterial needle is opposite to the blood flow in every hemodialysis session.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Prevalence of AVF aneurysm and stenosis. | Compare the prevalence of AVF aneurysm and stenosis between two groups during 12 months. | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Proportions of AVF dysfunction in different groups. | Compare the proportions of AVF dysfunction between two groups during 12 months. | 12 months | 
| The size of venous aneurysm. | Measure the maximum size of venous aneurysm by using ultrasonography at month 12. | 12 months | 
| Diameter of venous stenosis. | Measure the minimum diameter of venous stenosis by ultrasonography at month 12. | 12 months | 
| Percentages of unsuccessful cannulations. | Unsuccessful cannulations include mis-cannulation, cannulation ease, hematoma, more than once cannulation at arterial site. | 12 months | 
| Events of AVF obstruction. | AVF obstruction and the following treatments as central venous catheters and interventions will be recorded and compared between two groups during 12 months. | 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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arteriovenous fistula, hemodialysis, aneurysm, vascular stenosis, cannulation