End stage renal failure (ESRF)describes an irreversible loss in renal function. The majority of these patients will opt for haemodialysis (HD)as their chosen method of renal replacement therapy (RRT). Arteriovenous fistulae (AVF) are the optimal method of achieving vascular access to permit HD. AVF are created with a small surgical procdure to join the artery and vein together. Over the next 6- 8weeks after surgery the AVF should grow ("mature") into a vessel suitable for needles to be inserted for dialysis. Unfortunately however, around 24% - 35% of AVF fail at an early stage. Some anaesthetic techniques can influence intraoperative blood flow and venous diameter, factors which are associated with fistula success. There remains no conclusive evidence that any particular anaesthetic technique can significantly influence long term surgical outcome. This study aims to investigate whether a regional, compared to local, anaesthetic technique can affect fistula patency.