To assess the patency of an arteriovenous vascular access, which of the following should the technician initially feel for?

To assess the patency of an arteriovenous (AV) vascular access, feeling for a thrill is a crucial initial step. A thrill refers to the palpable vibration felt over the vascular access site, caused by the turbulence of blood flow. When an AV access is patent (open and functioning properly), it will produce this characteristic vibration due to the high-speed blood flow from the artery into the vein.

In the context of vascular access for dialysis, the presence of a thrill indicates that the access is functioning properly and that there is good blood flow. If a thrill is not felt, it may indicate issues such as stenosis (narrowing) or thrombosis (blockage), which could compromise the effectiveness of dialysis.

While other assessments, such as checking for a bruit (a sound heard with a stethoscope) or feeling for a pulse, are also important in evaluating vascular access, they are secondary to feeling for a thrill. Edema indicates fluid retention and does not directly assess the functionality of the vascular access. Overall, palpating for a thrill provides immediate feedback about the access's usability for hemodialysis.