Routine use of arteriovenous fistula construction to dilate the venous outflow prior to insertion of an expanded polytetrafluoroethylene (PTFE) loop graft for dialysis.

For long-term haemodialysis to be successful an adequate length of vessel with correspondingly high flow is necessary, and the use of a peripheral arteriovenous fistula (AVF) between brachial artery and median cephalic vein is well described for long-term vascular access. However, the length of vessel available is often insufficient for dialysis and the time-lag between formation and availability for use may be prolonged. Primary insertion of a PTFE interposition graft is an alternative but may be technically difficult due to the small diameter of vein available for run-off, resulting in a significant rate of thrombosis. We advocate early AVF formation in most patients, even where the fistula is unlikely to prove usable for dialysis, with the express purpose of dilating the veins prior to PTFE graft insertion. The time-lag between AVF formation and PTFE graft insertion may be as short as 1 week. Although conversion of a functioning AVF to PTFE interposition graft has been described by others, we believe the routine use of AVF formation prior to PTFE insertion has not been previously advocated and gives a considerable advantage in patients with difficult dialysis access.