Arteriovenous fistula monitoring using ultrasound scans

25 August 2022

Dialysis, one of the treatment options for chronic kidney disease, is a procedure to remove waste and excess fluid from the blood. To administer dialysis, there must be a pathway for blood to flow into an external machine where it is filtered, and the clean blood to be passed back into the patient. This pathway is referred to as a vascular access. To establish this vascular access, an arteriovenous (AV) fistula must be surgically created which is then used as a long-term pathway for dialysis.

Unfortunately, the average lifespan of an AV fistula is five years, with its function declining over time. When an AV fistula fails, it can cause disruption to planned dialysis and requires surgical creation of a new AV fistula. These can have a detrimental effect on the patient’s physical and mental wellbeing. Although it is certain that an AV fistula will ultimately fail, when this will happen is unknown and dialysis recipients often live with anxiety.

Dr Yongmann Chung

Fistula monitoring could allow early detection of failure

Dr Yongmann Chung from University of Warwick, and his interdisciplinary team (Dr Bjorn Stinner at Mathematics and Professor Charles Hutchinson at Warwick Medical School) propose a new fistula monitoring process using ultrasound scanning.

Working with dialysis patients at Royal Berkshire Hospital, Yongmann will use an ultrasound machine to scan dialysis patient's fistula during their regular hospital visits. The use of ultrasound scanning is safe, cost effective and has low risk in relation to the frequency to which scans will be done.

Yongmann and his team will also use a simulation process called computational fluid dynamics (CFD) to better understand the dynamics of blood flow in the AV fistula. Through ultrasound scanning, a 3D fistula imaging model for each patient will be created and used for CFD study. This is hoped to help inform on the potential success or failure of fistula function and through monitoring, show early signs of fistula failure.

Being able to view and understand the dynamics of blood flow in kidney patient's fistula can help detect signs of fistula failure before it happens. If this can be identified early enough, interventions can be made to keep fistula function longer. This can significantly ease the physical and emotional burden on dialysis patients and improve the outcome of fistula dialysis.

Yongmann said: “This award can enable us to start a high impact research which can make a real difference to kidney patients. The use of high-performance computing together with advanced medical imaging analysis will help us understand and detect the early signs of fistula failure. This award will strengthen the on-going research collaboration between University of Warwick and Royal Berkshire Hospital”