Final answer:
The primary way that a nurse will evaluate the patency of an AVF is by auscultating for the presence of a bruit at the site.
Step-by-step explanation:
The primary way that a nurse will evaluate the patency of an AVF (arteriovenous fistula) is by auscultating for the presence of a bruit at the site. A bruit is a blowing or swishing sound that can be heard when there is turbulent blood flow through the AVF. This indicates that the AVF is open and functioning properly.
To auscultate, the nurse places a stethoscope on the patient's AVF site and listens for the presence of the bruit while the patient's arm is relaxed and not being compressed.