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Trial details imported from ClinicalTrials.gov

For full trial details, please see the original record at https://clinicaltrials.gov/study/NCT00829153




Registration number
NCT00829153
Ethics application status
Date submitted
22/01/2009
Date registered
26/01/2009
Date last updated
16/03/2010

Titles & IDs
Public title
U Clip Study - Study to Compare U Clip Anastomosis With Conventional Continuous Prolene Anastomosis
Scientific title
A Pilot, Randomised, Blinded Study to Compare U Clip Anastomosis With Conventional Continuous Prolene Anastomosis for Creating of Autologous Arteriovenous Fistulae
Secondary ID [1] 0 0
H8974
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Haemodialysis 0 0
Condition category
Condition code

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Treatment: Devices - U Clip
Treatment: Surgery - Conventional prolene anastomosis

Experimental: U clip - Anastomosis with U clips

Active comparator: 2 - Prolene anastomosis


Treatment: Devices: U Clip
Interuppted nitional clips

Treatment: Surgery: Conventional prolene anastomosis
Continuous prolene anastomosis
Intervention code [1] 0 0
Treatment: Devices
Intervention code [2] 0 0
Treatment: Surgery
Comparator / control treatment
Control group

Outcomes
Primary outcome [1] 0 0
A functioning fistula which is used for haemodialysis on three or more occasions.
Timepoint [1] 0 0
Until commencement of dialysis with the fistula
Secondary outcome [1] 0 0
Fistula patency as assessed clinically.
Timepoint [1] 0 0
For the life of the fistula
Secondary outcome [2] 0 0
Need for fistula intervention in order to maintain patency.
Timepoint [2] 0 0
For the life of the fistula

Eligibility
Key inclusion criteria
1. Requirement for AV fistula creation for haemodialysis
2. Pre operative upper limb venous and arterial duplex scan showing intended arterial lumen diameter of 2mm or more and vein diameter of 3mm or more.
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
1. Use of prosthetic graft for fistula creation.
2. Donor arterial lumen diameter less then 2mm
3. Recipient venous diameter less than 3mm.
4. Proximal venous thrombosis.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s
The people administering the treatment/s

Intervention assignment
Parallel
Other design features
Phase
Phase 1
Type of endpoint/s
Statistical methods / analysis

Recruitment
Recruitment status
UNKNOWN
Data analysis
Reason for early stopping/withdrawal
Other reasons
Date of first participant enrolment
Anticipated
Actual
1/01/2007
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
40
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
Recruitment hospital [1] 0 0
Launceston general Hospital - Launceston
Recruitment postcode(s) [1] 0 0
- Launceston

Funding & Sponsors
Primary sponsor type
Government body
Name
Royal Hobart Hospital
Address
Country

Ethics approval
Ethics application status

Summary
Brief summary
The requirements for haemodialysis are increasing. There is now acceptance that the most durable AV fistulae are those created from the patients own veins. Use of the radiocephalic arteriovenous fistula as an autologous vascular access dates back to the 1960's. (Brescia MJ, Cimino JE. Appel K, Hurwich BJ. Chronic hemodialysis using venipuncture and a surgically created arteriovenous fistula. N Engl J Med 1966; 275: 1089 - 1092.) Once established, it has good long term survival and a low complication rate. However, the success rate at creation of a useable AV fistula are not good. In a meta-analysis published in 2005, the primary failure rate of a radiocephalic fistula was 15.3% and the primary and secondary patency rates were 62.5% and 66.0% at one year. (Rooijens PPGM, Tordoir JHM, Stijnen T, Burgmans JPJ, Smet AAEA and Yo TI. Radiocephalic wrist arteriovenous fistula for hemodialysis: meta-analysis indicates a high primary failure rate. Eur J Vasc Endovasc Surg 2004; 28, 583-589). Reasons for this are multiple but it appears as though the main determinants are the quality of the patients veins and the technical skill of the surgeon. Low patency rates are also seen in females and those with small veins and arteries. Creating an anastomosis between a small vein and artery is technically challenging. This is traditionally preformed with a continuous prolene suture. Recently, Medtronic have been marketing the U Clip Anastomotic Device. This is a self closing devise which could be called a vascular clip. Reported advantages of this clip include better patency rates and faster operations. However, to our knowledge there is no randomised evidence to support this with regards to AV fistulas.

The vascular anastomosis originally developed by Alexis Carrel used interrupted sutures. Over time this was replaced by a continuous suture technique which was felt to be quicker and had similar patency rates. However, microvascular, paediatric and neurovascular surgeons have shown that there are advantages to an interrupted technique. (Hattori H, Killen DA, Green JW. Influence of suture material and technic on patency of anastomosed arteries of less than 1.5mm. Am Surg. 1970; 36: 352 - 354. Cobbett JR. Microvascular surgery. Surg Clin N Am. 1962; 47: 521.). The reasons for the improved patency with interrupted anastomoses are firstly increased anastomotic compliance and flow rate and secondly elimination of the pursestring effect and puckering seen with continuous sutures.

In a prospective but non randomised study to compare interrupted U clips with historical published results, the patency rate of coronary anastomoses was 100% at 6 months using the U clips compare to a patency rate of 90 -100% in the published series. (Wolf RK, Alderman EL, Caskey MP et al. Clinical and six month angiographic evaluation of coronary arterial graft interrupted anastomoses by use of a self closing clip device: a multicentre prospective clinical trial. J Thorac cardiovasc Surg 2003; 126(1): 168 - 178.)

Reports from single centres have concluded that the U Clips offer the opportunity to create superior interrupted anastomoses for AV fistula, even in patients who would otherwise be considered poor candidates for fistula creation. (Ross JR. Creation of native arteriovenous fistulas with interrupted anastomoses using a self closing clip device - one clinics experience. Journal of vascular Access 2002; 3: 140 - 146). In this report with small numbers, the radiocephalic fistulas had an 8 week maturation rate of 93%. Of the 28 patients having a radiocephalic fistula, 10 had veins of between 1.0 - 1,5mm diameter.

The aim of this pilot study will be to assess if there is a clinical difference in the maturation rates of autologous AV fistulae when a clipped anastomosis is compared to a conventional prolene anastomosis.
Trial website
https://clinicaltrials.gov/study/NCT00829153
Trial related presentations / publications
Walker SR. U Clips for arteriovenous anastomosis: a pilot, randomized study. ANZ J Surg. 2012 Sep;82(9):630-2. doi: 10.1111/j.1445-2197.2012.06153.x. Epub 2012 Aug 20.
Public notes

Contacts
Principal investigator
Name 0 0
Address 0 0
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Stuart R walker, MBBS
Address 0 0
Country 0 0
Phone 0 0
03 6227064
Fax 0 0
Email 0 0
[email protected]
Contact person for scientific queries



Summary Results

For IPD and results data, please see https://clinicaltrials.gov/study/NCT00829153