N7 — AVF/AVG Assessment and Cannulation

When: before every cannulation, and at needle removal.

Do this

1. Wash and look. The patient washes the access arm before cannulation. Look for redness, swelling, drainage, skin breakdown, thin or shiny skin over an aneurysm, a cool or discolored hand, and neck or chest collaterals [5].
2. Listen. Normal: low-pitched, continuous bruit. Abnormal: high-pitched, systolic-only, or absent.
3. Feel. Normal: soft, compressible vessel with a thrill. Abnormal: hard pulsatile segment, weak thrill, “mushy” graft, or no thrill.
4. Test. Raise the arm — a fistula should collapse. Occlude above the anastomosis — the pulse should augment.
5. Confirm flow direction before placing needles; use ultrasound for a new or difficult access if trained.
6. Rope ladder: rotate both sites along the full length of the access. No area puncture [5].
7. Needles: gauge matched to the prescribed blood flow per your unit protocol. Venous needle always antegrade; avoid a retrograde, bevel-down arterial needle [6].
8. First cannulations of a new fistula go to the most skilled cannulator.
9. After dialysis: firm pressure on the puncture site — enough to stop bleeding, not enough to lose the thrill.

Call the nephrologist when

• Same day: no thrill and no bruit; a rapidly expanding hematoma; a cold, pale, painful, or weak hand; bleeding you cannot control; thin, shiny, ulcerated, or scabbed skin over an aneurysm.
• Before the next session: pus, spreading redness, or fever — cultures before antibiotics.
• At rounds: new difficulty cannulating, clots aspirated, prescribed blood flow not reached, needle sites bleeding longer than usual for 3 sessions in a row, an unexplained Kt/V drop of more than 0.2, or arm, face, or breast swelling [5].

Don’t

• Don’t cannulate a fistula within 14 days of creation [3], or before the access team has cleared it.
• Don’t buttonhole a graft — ever. Don’t start a buttonhole without an order and an indication [2].
• Don’t needle the top of an aneurysm.
• Don’t allow BP cuffs, IVs, or blood draws on the access arm (per your unit protocol); flag any PICC request to the nephrologist.
• Don’t press on the vessel downstream of a bleeding point.