Con: Vascular access surveillance in mature fistulas: is it worthwhile?

The risks and benefits of hemodialysis arteriovenous (AV) access surveillance have been debated since the introduction of AV access surveillance techniques. The debate is fuelled by the lack of robust, high-quality evidence with consistent and comparable patient-important outcomes. Additionally, there is a lack of clarity regarding the diagnostic cut points for AV access stenosis using the various surveillance techniques, questions about the appropriateness of the 'knee-jerk' response to intervention on a stenosis >50% regardless of the presence of clinical indicators and whether the intervention results in desired patient-important outcomes. The physiology of the AV access is complex considering the different hemodynamics within an AV fistula, which vary by time of dialysis, location, size of vessels and location of the stenosis. The current evidence suggests that the use of AV access surveillance in an AV fistula does detect more stenosis compared with clinical monitoring alone and leads to an increased number of procedures. It remains uncertain if that leads to improved patient-important outcomes such as prolonged AV fistula patency. Vascular access is an essential component of hemodialysis and further study is needed to clarify this long-standing debate. There needs to be better distinction between the strategies of vascular access surveillance, clinical monitoring with clinical indictors and preemptive intervention and their respective impacts on patient-important outcomes. Randomized controlled studies must be conducted with defined indications for intervention, reproducible methods of intervention and clinically important AV fistula and patient outcomes. The current guidelines need to be challenged and revised to permit these necessary studies to be done.