A third type of vascular access is a venous catheter. A venous catheter is a plastic tube which is inserted into a large vein, usually in the neck. An external portion of the catheter is exposed on the chest wall that allows the tubing for the dialysis machine to be connected. Because the catheter is not entirely under the skin, it is prone to infection. Venous catheters also have a high rate of becoming clogged and do not provide for as efficient dialysis as fistulas and grafts.
Venous catheters are generally considered temporary vascular accesses, and are usually only placed when urgent dialysis is needed. In rare cases, a tunnelled venous catheter may be used as long-term vascular access if no other options are available.