Transcript Document
Haemodialysis Fistula Intervention Dr Ralph Jackson Freeman Hospital Newcastle-upon-Tyne What are Arterio-Venous fistulae? • Surgically created “end to side” shunts which allow dialysis. • Lower arm (radio-cephalic) better than upper arm (brachio-cephalic, brachiobasilic, brachio-brachial). • Native better than grafts (PTFE, bovine ureter) Anatomy Typical AV Fistula “Venous” needle Thrill “Arterial” needle Typical AV Fistula Venous pressure Arterial pressure Problems with fistulae • Poor development • Difficulty needling • Inadequate dialysis – Low flow rates – Recirculation • High pressures and prolonged bleeding • Thrombosis • Almost all due to stenoses which are recurrent Flat AV Fistula: peri-anastomotic stenosis “Venous” needle Weak thrill “Arterial” needle Pulsatile AV Fistula: stenosis away from anastomosis Flat Remote Thrill Pulsatile and high pressure Recirculation Thrill “Venous” needle “Arterial” needle Treatment options • Angioplasty – Standard balloon angioplasty – High pressure balloon – Cutting or scoring balloon • Surgery • Refashion anastomosis • Patch stenosis • Higher fistula • Whichever way, get on with it. Balloon angioplasty • Big enough – Tendency to use too small balloons • High or ultra high pressure – Standard RBP of 15Atm @8mm • Inflation handle (obviously). • Long inflation times as recoil common. • Rupture uncommon but be prepared Antegrade transvenous Retrograde transvenous Transarterial Standard pressure balloon High Pressure Cephalic arch stenosis Much commoner in dysfunctional brachiothan radio-cephalic fistulae (~50%). More prone to rupture and restenosis Primary patency rates at one year after angioplasty only around 30% Rupture management • Not that frequent to have major rupture (12%). • Tamponade with long low pressure inflation • Covered stent as bail out • Associated with subsequent loss of fistula Balloon Tamponade Covered stent/stent graft Covered stent/stent graft Covered stent/stent graft Covered stent/stent graft Covered stent/stent graft Conclusion • AV fistulas are simple to understand. – History and examination are diagnostic. • Most problems are due to stenosis. • Angioplasty is highly successful if done right. • Stenoses recur so you will get to know the patients well. • Maintaining dialysis access is one of the most important IR jobs.