Wireless, non-invasive, high-resolution thrill sensor for continuous vascular access monitoring of hemodialysis patients

Hemodialysis is the primary life-sustaining therapy for patients with end-stage renal disease (ESRD). Diagnosing and monitoring the health condition of vascular access (VA) for hemodialysis involves the use of ultrasonic imaging and angiography. These infrequent tests cannot, however, identify signs of mild stenosis and sudden onset to facilitate early intervention. Hence, approximately 70% of hemodialysis patients experience VA failure each year, rendering dialysis difficult and posing life-threatening risks. Here, we report wireless, non-invasive thrill sensors incorporating high-resolution accelerometers designed to be conformally placed on VA skin for the continuous monitoring of VA thrill signals, which we tested in multi-platform validation including an in vitro benchtop system, canine models and patients (n = 9). Local measurements of VA thrill intensity via continuous wear demonstrated that a decrease in thrill intensity along the entire VA region is indicative of diminished VA function, while an abnormally heightened thrill intensity at a certain location along the VA indicates localized structural lesions. These thrill sensors may aid the early treatment of VA stenosis upon the transition from subjective thrill palpation to quantitative hemodynamic phenotyping. Early detection of vascular access dysfunction is critical for hemodialysis patients, but current monitoring lacks continuous solutions. Here, the authors develop a wireless, noninvasive sensor that enables VA monitoring by detecting thrill intensity changes.