A fistula is made by linking an artery to a nearby vein. The high pressure and blood flow in the artery are transferred into the vein. They help the vein grow in size and thickness. The enlarged vein (fistula) eventually has high blood flow. It becomes thick enough for needles to be placed safely several times each week during hemodialysis. It may need weeks or months to develop before it's ready to be used. A fistula works better than a graft. It also has fewer long-term problems. It is generally the preferred form of access.

A graft (piece of synthetic tube) may be sewn between an artery and a vein. It's often used if a fistula is not possible because of the small size of your veins. Blood flows quickly through the graft from the artery to the vein. A graft is often ready to use in a few weeks. Needles can be placed into the plastic tube to get blood during dialysis.