av Fistula Patency Loss as a Cause of Fistula Failure and Hyperphosphatemia

Study Overview
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Brief Summary
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Assessment of arteriovenous fistula patency loss which leads to av fistula failure and its relation to high serum phosphate level in chronic hemodialysis patients.

Detailed Description
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End-stage renal disease is a chronic disease requiring treatment with dialysis or renal transplantation. Patients require an adequate vascular access for hemodialysis (HD). Autologous arteriovenous fistula (AVF) is gold standard to maintain vascular access for HD . Vascular access-related complications can lead to patient morbidity and reduction of patient quality of life.The complication rate related to permanent HD vascular access remains relatively high and access related problems are responsible for 50% of the hospitalization of dialysis patients. Secondary failures are not rare and in need of adequate attention and care. Once the AVF has been placed. It is recommended that serial monitoring of the AVF should be done for long term effective function. Delays in preventing complications may lead to AVF dysfunction. However, little is known about the factors determining long term prognosis of an AVF. Primary patency (intervention-free access survival) was defined as the interval from time of access placement to any intervention designed to maintain or reestablish patency or to access thrombosis or the time of measurement of patency. Assisted primary patency (thrombosis-free access survival) was defined as the interval from time of access placement to access thrombosis or time of measurement of patency, including intervening manipulations (surgical or endovascular interventions) designed to maintain the functionality of a patent access. Secondary patency (access survival until abandonment) was defined as the interval from time of access placement to access abandonment or time of measurement of patency, including intervening manipulations (surgical or endovascular interventions) designed to reestablish the functionality of thrombosed access . In patients having chronic renal failure (CRF), several changes occur in bone metabolism due to the development of secondary hyperparathyroidism. There are increased calcium and phosphate release from bones to the blood, causing the deposition of calcium and phosphate in the intima-media layer of arterial wall and eventuating vascular calcification in these patients. The deposition of these electrolytes increases the risk of cerebrovascular and coronary complications as well. Thus, a decrease in the quality of fistula occurs in these tracts utilized frequently at the arteriovenous fistula (AVF) operations.

Official Title
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av Fistula Patency Loss as a Cause of Fistula Failure and Its Relation to Hyperphosphatemia in Chronic Hemodialysis Patients

Conditions
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AV Fistula

Intervention / Treatment
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* Device: doppler ultrasound


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: adult patients more than 18 years old with end stage renal disease on regular hemodialysis using arteriovenous fistula Exclusion Criteria: : patients less than 18 years, patients with peripheral artery diseases, access failure occurred within the first 2 months after fistula surgery, AVF failure was related to an infectious complication and patients with arteriovenous grafts.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| av fistula patency loss with hperphosphatemia<br>hemodialysis patients with av fistula patency loss by doppler ultrasound and hyperphosphatemia | Device: doppler ultrasound<br>* doppler ultrasound on arteriovenous fistula in hemodialysis patients<br>|
| av fistula patency loss with normal phosphate level<br>hemodialysis patients with av fistula patency loss by doppler ultrasound and normal phosphate level | Device: doppler ultrasound<br>* doppler ultrasound on arteriovenous fistula in hemodialysis patients<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| measurement of early av fistula patency loss | early measurement of av fistula patency loss using doppler ultrasound to decrease the fistula failure rate | baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| measurement if there is a relation between fistula patency loss and hyperphosphatemia | analysis if a high serum phosphate level leads to arteriovenous fistula patency loss | baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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hyperphosphatemia