Ultrasoundguided cannulation of hemodialysis access

Because hemodialysis therapy cannot be performed without the cannulation of a vascular access, establishing a wellfunctioning vascular access is crucial. Recently, the number of patients with difficult arteriovenous (AV) fistula cannulation has increased due to changes in the epidemiology of the dialysis population. To address this issue, indications for realtime ultrasoundguided techniques have recently been reported. This review discusses methods of ultrasoundguided cannulation of dialysis access; it is difficult to cannulate a deep, small, or stiff vessel of an AV fistula on the first attempt with static ultrasound guidance in which the ultrasound probe remains stationary. Mastering a method in which the precise location of the needle tip can be continuously identified during the insertion by dynamic probe scanning is required. To achieve this, understanding the theory of ultrasound guidance, off/onthejob training, and a sense of professionalism are important. The use of ultrasound also enables the safe catheter placement into a collapsed central vein and repeated direct puncture of a femoral vein. The latter reduces the risk of catheterrelated blood stream infection by avoiding the use of an indwelling duallumen catheter. In conclusion, ultrasoundguided techniques enable precise vascular cannulation, which can result in significant patient and financial impact. The accumulation of further reports is required for the method to be acknowledged as the standard to cope with difficult vascular access for dialysis. As most of the latest ultrasound machines for procedural guidance are optimized for peripheral nerve block, a compact and affordable ultrasound device with image quality focused on vascular access is also needed.