Does regional (RA) compared to local anaesthesia (LA) improve unassisted functional patency at 1-year and/or cost-effectiveness in patients undergoing primary radio- (RCF) or brachio-cephalic (BCF) fistula creation?
Arteriovenous fistulae (AVF) are the “gold standard” vascular access for haemodialysis, however universal usage is limited by a high early failure rate. Several small studies, including our own single-centre randomised controlled trial (RCT), previously demonstrated better early patency rates for AVF created under RA versus LA. The mechanistic hypothesis is that sympathetic blockade causes vasodilatation and increased blood flow through the new AVF. Despite this, considerable variation in practice exists in the UK. A high quality, adequately powered, multicentre RCT is required to definitively inform practice.
Aims and Objectives:
A multicentre, single-blinded RCT comparing RA (ultrasound-guided supraclavicular or axillary block with 1:1 mixture of 0.5% L-bupivacaine and 1% lidocaine, with epinephrine (final concentration 1 in 400,000)) and LA (local infiltration with 1:1 mixture of 0.5% L-bupivacaine and 1% lidocaine) in patients undergoing primary RCF or BCF creation.
566 patients will be recruited from up to 20 UK centres. An internal pilot with stop/go checkpoint after 4 months (95 patients) will ensure the ability to recruit.
Unassisted functional patency at 1-year, defined as the ability of the access to uninterruptedly deliver the prescribed dialysis without intervention at 12 months. In pre-dialysis patients, this will be defined both clinically (assessment by a blinded dialysis nurse) and ultrasonographically (4mm diameter and access flow >500ml/min).
Access-related complications e.g. infection, thrombosis; re-interventions to maintain/ re-establish patency; hospitalisation; alternative accesses; mortality; safety, efficacy and acceptability of anaesthetic technique and health-related quality of life measures (EQ-5D, KDQOL-SF and VAS-QoL (a novel vascular access specific tool). These will be assessed at 3 and 12 months.
Intention-to-treat and per protocol analyses will be performed as well as health economic evaluation. A rapid feedback evaluation study will run in parallel to the main trial collecting qualitative data on recruitment and retention. Findings will be shared with the trial team on a regular basis to inform trial delivery.
Timeline for delivery:
The trial commenced in May 2021. Recruitment will take two years. Follow- up will take one year. Results are anticipated in November 2024.
Anticipated impact and dissemination:
Results will have direct implications for patient care across a range of medical specialties (surgery, anaesthesia, nephrology, dialysis nursing). They will be presented at international scientific conferences and published in a high impact peer-reviewed medical journal. It is anticipated that results will provide NICE level evidence to influence NHS commissioning and that recommendations be incorporated into the Renal Association’s next ‘Vascular Access for Haemodialysis’ guideline.