Kidney Dialysis

Your kidneys help filter waste, excess fluid, and toxins from your blood.  They are also important for blood cell production and bone health.  If kidneys don’t work properly, harmful substances build up in the body, blood pressure can rise, and too much fluid can collect in the body’s tissues, which leads to swelling, called edema.
If your kidneys fail, you will need dialysis or a kidney transplant to take over their job.

When is dialysis needed?
You need dialysis when you develop end stage kidney failure-usually by the time you lose about 85 to 90 percent of your kidney function and have a GFR.

What is Kidney Dialysis?
Kidney dialysis is a life-support treatment that uses a special machine to filter harmful wastes, salt, and excess fluid from your blood.  This restores the blood to a normal, healthy balance.  Dialysis replaces many the kidney’s important functions. 
There are different types of kidney dialysis, including:

  • Hemodialysis.  Blood is filtered using a dialyzer and dialysis machine.
  • Peritoneal dialysis.  Blood is filtered inside the body after the abdomen is filled with a special cleaning solution.

Where is dialysis done?
Dialysis can be done in a hospital, in a dialysis unit that is not part of a hospital, or at home.  You and your doctor will decide which place is best, based on your medical condition and your wishes.

What is hemodialysis?
In hemodialysis, an artificial kidney (hemodialyzer) is used to remove waste and extra chemicals and fluid from your blood.  To get your blood into the artificial kidney, the doctor needs to make an access (entrance) into your blood vessels.  This is done by minor surgery to your arm or leg.
Sometimes, an access is made by joining an artery to a vein under your skin to make a bigger blood vessel called a fistula.
However, if your blood vessels are not adequate for a fistula, the doctor may use a soft plastic tube to join tube to join an artery and a vein under your skin.  This is called a graft.
Occasionally, an access is made by means of a narrow plastic tube, called a catheter, which is inserted into a large vein in your neck.  This type of access maybe temporary, but is sometimes used for long-term treatment.

How long do hemodialysis treatments last?
The time needed for your dialysis depends on:

  • How well your kidneys work
  • How much fluid weight you gain between treatments
  • How much waste you have in your body
  • How big you are
  • The type of artificial kidney used

Usually, each hemodialysis treatment lasts about four hours and is done three times per week.
A type of hemodialysis called high-flux dialysis may take less time.  You can speak to your doctor to see if this is an appropriate.

What is peritoneal dialysis and how does it work?
In this type of dialysis, your blood is cleaned inside your body.  The doctor will do surgery to place a plastic tube called a catheter into your abdomen (belly) to make an access.  During the treatment, your abdominal area (called the peritoneal cavity) is slowly filled with dialysate through the catheter.  The blood says in the arteries and veins that line your peritoneal cavity.  Extra fluid and waste products are drawn out of your blood and into the dialysate.  There are two major kinds of peritoneal dialysis.

What are the different kinds of peritoneal dialysis and how do they work?
There are several kinds of peritoneal dialysis but two major ones are:

  • Continuous Ambulatory Peritoneal Dialysis (CAPD) and Automated Peritoneal Dialysis (APD).
  • Continuous Ambulatory Peritoneal Dialysis (CAPD) is the only type of peritoneal dialysis that is done without machines.  You do this yourself, usually four or five times a day at home and/or at work.  You put a bag of dialysate (about two quarts) into your peritoneal cavity through the catheter.  The dialysis stays there for about four or five hours before it is drained back into the bag and thrown away.  This is called an exchange.  You use a new bag of dialysate each time you do an exchange.  While the dialysate is in your peritoneal cavity, you can go about your usual activities at work, at school or at home.
  • Automated Peritoneal Dialysis (APD) usually is done at home using a special machine called a cycler.  This is similar to CAPD except that a number of cycles (exchanges) occur.  Each cycle usually lasts 1-1/2 hours and exchanges are done throughout the night while you sleep.