Which finding is an indication for duplex assessment of a hemodialysis access graft?

Which finding is an indication for duplex assessment of a hemodialysis access graft?

• A. Pre-op assessment
• B. Peri-graft mass
• C. Distal limb ischemia
• D. Loss of thrill

Answer: (D)

Loss of thrill signals potential graft dysfunction and is a key trigger for duplex evaluation of a hemodialysis access graft. When the graft is functioning well, a palpable thrill reflects adequate flow through the conduit. If that thrill disappears, it suggests the graft may be becoming occluded or severely narrowed, risking graft failure. Duplex ultrasound is the tool of choice to quickly characterize the problem: it can confirm whether the graft is patent or thrombosed, locate a stenotic segment, measure flow velocities, and assess downstream patency in the outflow vein. It provides the detailed flow information needed to plan an intervention, such as thrombectomy or angioplasty. Pre-op assessment is a planned imaging step before creating the access, not an acute indication. A peri-graft mass could point to a pseudoaneurysm or infection but is not the immediate sign of graft dysfunction. Distal limb ischemia raises concern for steal syndrome and warrants vascular assessment of the entire limb, but the direct sign indicating a need for evaluating the graft itself is the loss of thrill.

Loss of thrill signals potential graft dysfunction and is a key trigger for duplex evaluation of a hemodialysis access graft. When the graft is functioning well, a palpable thrill reflects adequate flow through the conduit. If that thrill disappears, it suggests the graft may be becoming occluded or severely narrowed, risking graft failure. Duplex ultrasound is the tool of choice to quickly characterize the problem: it can confirm whether the graft is patent or thrombosed, locate a stenotic segment, measure flow velocities, and assess downstream patency in the outflow vein. It provides the detailed flow information needed to plan an intervention, such as thrombectomy or angioplasty.

Pre-op assessment is a planned imaging step before creating the access, not an acute indication. A peri-graft mass could point to a pseudoaneurysm or infection but is not the immediate sign of graft dysfunction. Distal limb ischemia raises concern for steal syndrome and warrants vascular assessment of the entire limb, but the direct sign indicating a need for evaluating the graft itself is the loss of thrill.