Arteriovenous Graft (AVG)
When there is no usable vein for an AVF, an artificial or replacement vein can be used instead; this is called an arteriovenous graft (AVG). In this operation, instead of sewing the artery and vein directly to each other, a tunnel is made underneath the skin through two small incisions in the arm or thigh, and an artificial tube (made of polytetrafluoroethylene, a waterproof material) or a donated artery or vein is pulled under the skin through the tunnel. The graft is then sewn to the artery on one end and to the vein on the other, and the skin is closed, covering the graft. At dialysis, needles are put through the skin into the graft the same way as how an AVF is used.
An AVG operation is also done as a come-and-go (outpatient) procedure and takes about an hour. Some grafts can be used almost immediately, and others within two to three weeks (rather than months like an AVF). Because the graft is not from the body’s own tissue, it has a higher risk of clotting and infection than an AVF. It also requires more care to keep it going and, on average does not last as long as an AVF.