What is dialysis?

Dialysis is for people who have kidney failure. When you have kidney failure, your kidneys are not able to cleanse your blood of wastes, including urea, and extra fluid. This process takes about three hours and is done three times a week.

What is hemodialysis?

Hemodialysis is a procedure that withdraws blood from the body into a machine that uses a special membrane (dialyzer) to filter wastes and remove extra fluid from the blood. Hemodialysis also restores the electrolyte balance in the blood.

Why do I need hemodialysis?

Hemodialysis is often started when symptoms or signs of kidney failure appear. These may include:

• Nausea, vomiting, anorexia, and fatigue due to “uremia,” a buildup of urea and other waste products in the blood that occurs when the kidneys are unable to eliminate wastes from your body. These wastes are poisonous to you when they reach high levels.
• High levels of potassium in the blood (“hyperkalemia”)
• Fluid overload
• High levels of acid in the blood
• Hemodialysis is sometimes used for people who have acute (sudden) kidney failure.

Are there any risks associated with hemodialysis?

Dialysis is always used with extra caution in people who have acute kidney failure. Dialysis can cause low blood pressure, an irregular heart rhythm (cardiac arrhythmia), and other problems that can sometimes make acute kidney failure worse.

What is a hemodialysis access?

Because of the need to remove blood from the body and replace it during hemodialysis, a means for accessing the patient’s blood circulation — called “vascular access” — is necessary. There are three different techniques for this, some of which are used interchangeably: dialysis fistula, graft, and catheter. All of these techniques are able to withdraw and replace large amounts of blood at the same time – about one quart per minute.

What is a fistula?

The most desirable form of hemodialysis vascular access is called a fistula. To make a fistula, a surgeon connects an artery to a vein in the forearm or upper arm. With time, usually one to three months, the vein enlarges and becomes ready to receive the needles used to withdraw and replace blood during dialysis. A fistula can last for many years if the vein enlarges and the fistula “develops.” About three-quarters of fistulas develop or mature. During the time that a fistula is developing, if hemodialysis is necessary, another form of vascular access will be necessary, usually a catheter.

What if my fistula does not develop?

A non-developing or non-maturing fistula occurs in up to one-fourth of patients. There are two causes for a non-maturing fistula: narrowing of a vein or too many competing veins. Interventional radiologists can either open up the narrowed vein with a balloon (balloon angioplasty) or close off the competing veins using several techniques. About three quarters of people with non-maturing fistula will benefit from one or both of these treatments and have their fistula develop so it can be used. These procedures are done as an outpatient and take about an hour.

Protect your veins!

In order to make a fistula, you must have good arteries and good veins. While you generally cannot do much about your arteries, you are in control of your veins. As soon as a diagnosis of kidney failure is made, you should be very careful not to let anyone puncture the veins of your forearm or upper arm for blood draws, intravenous medications, or for any other reason. The hand veins should serve this purpose. By doing so, you protect your veins.