A Study of Routine Versus Selective Use of Ultrasound Scanning Prior to Haemodialysis Fistula Surgery

Study Overview
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Brief Summary
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Dialysis patients have their blood filtered by a machine as their kidneys no longer work. To get blood in and out of these patients it is possible to perform a surgical procedure to increase to size and durability of a vein in the arm to allow repeated needle insertion. This enlarged vein is called a fistula. There is some evidence that ultrasound scanning the blood vessels in the arm before surgery can improve the chances of a successful procedure. The investigators aim to test whether scanning all patients is better than scanning only those who are difficult to assess by physical examination alone.

Detailed Description
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We will recruit all patients undergoing primary vascular access procedures in our unit who meet inclusion criteria. They will be randomised to either surgery based on clinical findings with duplex ultrasound only if requested by surgeon, or routine duplex ultrasound prior to surgery.

Official Title
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A Prospective Randomized Controlled Trial of the Clinical Effectiveness of Obligatory Versus Elective Duplex Ultrasound Scanning Prior to Arteriovenous Fistula Formation for Haemodialysis Vascular Access in a University Teaching Hospital.

Conditions
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End Stage Renal Failure, Surgery

Intervention / Treatment
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* Procedure: Arterial and venous duplex ultrasound examination


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Specific inclusion criteria necessary for invitation to study participation; Patients referred to vascular consultants for primary AV fistula formation (or primary fistula in that limb) for haemodialysis access. General inclusion criteria; Ability to give informed written consent Exclusion Criteria: Specific exclusion criteria; Previous arterial or venous surgery/intervention performed on target limb. Known thrombophilic or thrombotic pathology. Aged under 18 at time of referral General exclusion criteria; Inability to give informed written consent Inability to attend follow up appointments

Ages Eligible for Study
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Minimum Age: 18 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: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control group - selective duplex<br>Patients will receive a duplex ultrasound only if specifically requested following physical examination. | |
| Experimental: Obligatory Duplex scan<br>Patients will receive a duplex ultrasound regardless of clinical findings. Arterial and venous duplex ultrasound examination | Procedure: Arterial and venous duplex ultrasound examination<br>* Ultrasound mapping of all blood vessels in the upper limb of interest<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Primary failure of access (immediate/early thrombosis or failure to mature). |  | 30 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Assisted primary patency - being the interval from placement until the time of measurement of patency, including intervening manipulations |  | open ended | 
| Secondary patency - The interval from placement until time of patency measurement including intervening manipulations |  | open ended | 
| Site of fistula created |  | within 1 month of recruitment | 
| Functional primary patency - being the interval from the time of access placement until any intervention designed to maintain or re-establish patency or the time of measurement of patency during which the AVF provides dialysis access. |  | open ended | 
| Surgeon grade |  | open ended | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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fistula, ultrasound, angioaccess, preoperative vein mapping, Haemodialysis, Angioaccess surgery