Surgical management of failing arteriovenous fistulae

Introduction

Maintenance adaequate haemodialysis therapy depends on a reliable access to circulation, preferably a native arteriovenous fistula (AV fistula). As an AV fistula is a very dynamic high flow construction and, in addition, cannulated repeatedly it is prone to dysfunction and finally to failure, mostly thrombosis. Aim of any type of management of fistula dysfunction is to restore an intact and patent venous tube for long-term use. Recently, a tendency is observed to treat the dysfunctional, failing fistula electively. Main topics of this overwiew are stenosis, aneurysm, peripheral ischaemia/steal syndrome and missing maturation. These remarks concentrate on surgical aspects.

Diagnosis of the failing arteriovenous fistula

Early diagnosis of the failing AV fistula is an essential goal for the nephrologist and his staff. Bedside clinical examination - inspection, palpation and auscultation - can reveal substantial findings, supported by routinely obtained dialysis related parameters like arterial/venous pressure and bleeding time after removal of cannulae. Case dependent, ultrasound examination can support and confirm clinical findings. In our institution, the synopsis of this simple procedure provides an exact and reliable diagnosis in more than 80% of patients. Recirculation studies are more predictive in AV grafts with outflow obstruction than in AV fistulae. Repeated measurements of blood flow volume has proven a valuable tool in various situations. In our experience, indications for angiography have decreased during the past years except for diagnosis of central vascular lesions.