What is the most reliable sign that an AV fistula is functioning adequately for dialysis?

What is the most reliable sign that an AV fistula is functioning adequately for dialysis?

• A. Audible bruit and palpable thrill
• B. Painful site
• C. Redness
• D. No buzzing

Answer: (B)

The most reliable sign that an AV fistula is functioning adequately for dialysis is the presence of both a palpable thrill and an audible bruit at the fistula site. The thrill is a vibrating sensation felt with the fingers as arterial blood enters the vein, and the bruit is the vascular murmur heard with a stethoscope from the turbulent high flow. Together, they indicate patency and sufficient flow for dialysis. Pain at the site, redness, or absence of a buzzing are not indicators of proper function and can signal possible problems such as infection, infiltration, or occlusion; thus they warrant further evaluation rather than confirmation of adequate function. Regularly checking for thrill and bruit before each dialysis session helps ensure the fistula remains usable.

The most reliable sign that an AV fistula is functioning adequately for dialysis is the presence of both a palpable thrill and an audible bruit at the fistula site. The thrill is a vibrating sensation felt with the fingers as arterial blood enters the vein, and the bruit is the vascular murmur heard with a stethoscope from the turbulent high flow. Together, they indicate patency and sufficient flow for dialysis. Pain at the site, redness, or absence of a buzzing are not indicators of proper function and can signal possible problems such as infection, infiltration, or occlusion; thus they warrant further evaluation rather than confirmation of adequate function. Regularly checking for thrill and bruit before each dialysis session helps ensure the fistula remains usable.