Hemodialysis Access

What is hemodialysis access?

Surgically created connection between an artery and vein for hemodialysis

What is hemodialysis?

Removal of creatine, urea, and water from blood of patients with end-stage renal disease

What is an AV fistula?

Surgical connection of an artery and vein for dialysis port access

What is the sonographic appearance required for the creation of an AV fistula?

1. Artery > 2 mm

2. Vein > 2.5 mm

3. Vein located < 1 cm in skin

4. Distal radial artery PSV > 50 cm/sec

5. RI < 0.7

What is a Brescia-Cimino fistula?

Connection of radial artery to cephalic vein at wrist

What is a “Snuffbox” fistula?

Connection of radial artery to cephalic vein at distal wrist

What is a brachiocephalic fistula?

Connection of brachial artery and antecubital vein at elbow

What is a brachiobasilic fistula?

Connection of brachial artery and basilic vein at elbow

What is a radiobasilic fistula?

Connection of radial artery and basilic vein in forearm

What is the protocol when evaluating an AV fistula?

1. Proximal evaluation of inflow artery and outflow vein

2. Evaluation of fistula

3. Distal evaluation of inflow artery and outflow vein

What is an AV graft?

Synthetic tube that indirectly connects an artery and vein for dialysis port access

What is the sonographic appearance required for the creation of an AV graft?

1. Artery > 2 mm

2. Vein > 4 mm

3. Vein located < 1 cm in skin

4. Distal radial artery PSV > 50 cm/sec

5. RI < 0.7

What is a straight synthetic graft?

Connection between brachial artery to basilic vein in upper arm

What is a looped synthetic graft?

Connection of brachial artery to antecubital or cephalic vein at elbow

What is the protocol when evaluating an AV graft?

1. Inflow artery proximal and distal to graft

2. Arterial or proximal anastomosis

3. Graft

4. Venous or distal anastomosis

5. Outflow vein proximal and distal to graft

What is the normal sonographic appearance of an AV fistula and graft?

1. Proximal arterial flow is low resistance

2. Proximal venous flow is turbulent, pulsatile, spontaneous, and phasic

3. PSV within graft: 100 - 400 cm/sec

4. EDV within graft: 60 - 200 cm/sec

5. Flow volume > 500 ml/min

6. Velocity ratio between graft and inflow artery < 3

7. Velocity ratio between two graft segments < 2

What is the most common site of stenosis in a hemodialysis graft?

Venous anastamosis

What is the most common cause of hemodialysis graft failure?

Thrombosis

What is steal syndrome?

Complication of hemodialysis access where blood flow is diverted away from hand and fingers due to radial and ulnar arteries sending blood in opposite directions

Where is steal syndrome most commonly found?

Radiocephalic fistula

Identify this image.

Steal syndrome