Maximizing Native Arteriovenous Fistulae Rates.

Study Overview
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Brief Summary
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The purpose of our study is to compare physical examination alone to color Doppler ultrasonography (CDUS) vascular mapping and physical examination in terms of outcomes of vascular access and long-term patency.

Detailed Description
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Fistula maturation is a complex vascular remodelling process that requires vessel dilation, increases in volume flow rates in the feeding artery and afferent vein and structural alterations of the vascular wall. The understanding of these procedures and the factors involved in promoting maturation is limited. In this context, one of the major areas requiring investigation is the identification of clinically useful pre-operative predictors of access outcome. Traditionally, the selection of vascular access and the eligibility for native arteriovenous fistula construction was mainly determined by findings of clinical examination. However, in addition to a complete history and physical examination, National Kidney Foundation/Dialysis Outcome Quality Initiative (NFK/DOQI) recommended that routine pre-operative color Doppler ultrasonographic vascular mapping should be performed in all hemodialysis patients who are candidates for access formation. This concerns the routine implementation of a non-invasive, safe and cost-effective method that permits the identification of vessels that are suitable for arteriovenous fistula (AVF) construction, acknowledging that supporting Level I evidence is still lacking. Indeed, available data supporting the significance of mapping on access maturation and patency rates are limited and conflicting. The aim of the present study is to compare the type of preoperative assessment, physical examination alone to combined CDUS vascular mapping and physical examination, to outcomes of performed vascular access procedures with respect to type selection and long-term patency at 12 months in hemodialysis patients.

Official Title
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Maximizing Native Arteriovenous Fistulae Rates. Is Routine Colour Doppler Vascular Mapping in Pre-operative Planning of Value? A Retrospective Study.

Conditions
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Kidney Failure, Arteriovenous Shunt, Hemodialysis

Intervention / Treatment
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* Procedure: preoperative color Doppler ultrasonographic vascular mapping
* Procedure: physical examination
* Procedure: medical history
* Procedure: native arteriovenous fistula construction
* Procedure: arteriovenous graft placement


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: end stage renal disease Exclusion Criteria: poor life expectancy congestive heart failure New York Heart Association stage 3 and over candidates for tunneled catheters
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 |
| --- | --- |
| Group A<br>Patients in whom selection of vascular access relied upon physical examination and medical history, during pre-operative surgical assessment | Procedure: physical examination<br>* Arterial pulse examination, differential blood pressure measurements and the Allen test in both extremities. Inspection of the superficial venous system with tourniquet enhancement in the arm was performed during venous assessment.<br>* Other names: clinical examination;Procedure: medical history<br>* medical history with respects to diabetes mellitus, coronary heart disease, peripheral vascular disease<br>Procedure: native arteriovenous fistula construction<br>* surgigal creation of native arterial and venous anastomoses<br>Procedure: arteriovenous graft placement<br>* surgical placement of arteriovenous graft<br>* Other names: Polytetrafluoroethylene (PTFE) synthetic graft;|
| Group B<br>Patients who underwent vascular mapping using color Doppler Ultrasonography in addition to physical examination and history during pre-operative evaluation. | Procedure: preoperative color Doppler ultrasonographic vascular mapping<br>* Preoperative color Doppler ultrasonographic vascular mapping was performed with linear probe. The patient extremity under scrutiny was placed under support, with tourniquet augmentation. Vessels were examined in both short (transverse) and long (longitudinal) axis. Anatomical variations, wall morphology and internal diameters at the antecubital fossa, the proximal (cranial), mid and distal (caudal) third of the arm and forearm were assessed in both extremities. Veins were evaluated for compressibility and adequate drainage to deep venous system. The presence of sclerotic, thrombosed and fibrosed segments were noted. Doppler waveforms were obtained in the long axis and volume flow (VF) calculated for arteries selected for potential access construction.<br>* Other names: pre-operative mapping;Procedure: physical examination<br>* Arterial pulse examination, differential blood pressure measurements and the Allen test in both extremities. Inspection of the superficial venous system with tourniquet enhancement in the arm was performed during venous assessment.<br>* Other names: clinical examination;Procedure: medical history<br>* medical history with respects to diabetes mellitus, coronary heart disease, peripheral vascular disease<br>Procedure: native arteriovenous fistula construction<br>* surgigal creation of native arterial and venous anastomoses<br>Procedure: arteriovenous graft placement<br>* surgical placement of arteriovenous graft<br>* Other names: Polytetrafluoroethylene (PTFE) synthetic graft;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| number of native AVF constructed |  | in 1 month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| primary patency rates |  | 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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arteriovenous fistula, colour Doppler, physical examination, renal dialysis, retrospective studies