Development of a Wearable Device for Arteriovenous Fistula Monitoring

Continuous monitoring of physiological parameters is a clinically significant approach for cardiovascular assessment. Chronic kidney disease (CKD) is a clinical status characterized by a progressive, irreversible impairment of renal function, which often requires hemodialysis through the surgical creation of a vascular access, called arteriovenous fistula (A VF). The latter requires frequent monitoring to avoid complications such as stenosis, thrombosis, and aneurysms. A VF monitoring is usually performed by doppler ultrasonography (DUS) magnetic resonance angiography (MRA) and digital subtraction angiography (DSA) which require specialized personnel and frequently is not available in a dialysis unit. In this paper will discuss the development of a wearable device based on a triboelectric sensor for monitoring of A VF in hemodialysis patients. The device is based on a layered sensor made of polyvinylidene fluoride (PVDF) and Kapton. The sensor, placed close the AVF, can evaluate the A VF status providing a triboelectric impedance cardiography (T -ICG) signal (i.e. blood acceleration). Temporal analysis of the T -ICG signals pattern evidenced significant changes in B-point morphology profile in patients with stenosis compared with patients with A VF but without stenosis. This device provides an alternative clinical method for the continuous monitoring of A VF in hemodialysis patients.