Types of arteriovenous fistula

An arteriovenous fistula connects an artery to a vein so that the vein receives a high flow, widens and thickens, and can be needled safely at every dialysis session.

Native fistulas (using your own veins)

• Radiocephalic: at the wrist. It is usually the first choice if the veins and arteries are suitable, because it leaves the rest of the arm free for future accesses.
• Brachiocephalic: at the elbow, using a vein on the outer side of the arm.
• Brachiobasilic: at the elbow, using a vein on the inner side of the arm. As it lies deep, it has to be brought closer to the surface (superficialisation), sometimes in two stages.

Graft fistulas

They connect an artery and a vein through a tube of synthetic material designed for dialysis. They are used when the veins are not suitable. Some types can be needled within a few days.

• Brachial-axillary: from the elbow to the armpit.
• Forearm loop: a U-shaped course.
• Thigh loop: when there are no options left in the arms.

Maturation and first needling

A native fistula usually needs several weeks to be ready. During that time it is monitored by examination and duplex ultrasound; if it does not mature well, it can often be corrected with angioplasty or minor surgery. The first needling is done by experienced dialysis staff.

Possible complications

• Stenosis or thrombosis of the fistula.
• Dilatations (aneurysms) at the needling sites.
• Steal syndrome: the hand receives less blood, causing coldness or pain.
• Infection, more common with grafts.

References

Patient information reviewed by Dr Óscar Merino, vascular surgeon. It does not replace an individual medical assessment.