Dialysis is a treatment for people in the later stage of chronic renal insufficiency (kidney failure). This treatment cleans the blood and removes wastes and excess water from the body. Normally, this work is done by healthy kidneys. The only other treatment for kidney failure is a kidney transplant.
There are two types of dialysis: hemodialysis and peritoneal dialysis. In hemodialysis, your blood is passed through an artificial kidney machine to clean it. Peritoneal dialysis uses a filtration process similar to hemodialysis, but the blood is cleaned inside your body rather than in a machine. The treatment normally takes three to five hours, and usually three treatments a week are needed. Only a small amount of your blood is out of the body at one time. Therefore your blood must circulate through the machine many times before it is cleaned.
You can be attached to the dialysis machine in different ways. The most common method of providing permanent access to the bloodstream for hemodialysis is an internal fistula in your arm. This involves having an artery and a vein connected surgically. When they are joined, the stronger blood flow from the artery causes the vein to become larger. Needles can be inserted in the enlarged vein to connect you to the dialysis machine.
Another way to provide access to the bloodstream is to insert an internal graft . In this procedure an artery is surgically connected to a vein with a short piece of special tubing placed under the skin. Needles can be inserted in this graft.
Sometimes, when it is necessary to gain access to the bloodstream quickly, or when the veins in the arms are too small to provide enough blood for hemodialysis, a central venous catheter is used. A soft tube is surgically inserted into a large vein in the neck or near the collarbone. This method is usually temporary until a permanent access site is ready.
Hemodialysis may be done in a hospital dialysis unit, in a self-care centre (with some assistance from the staff), or at home with the help of a partner or nurse. Special training is needed for self-care or home hemodialysis.