Dialysis is a procedure that performs the functions of natural kidneys when the kidneys fail. Most patients begin dialysis when their kidneys have lost 85% to 90% of their ability to function, and will continue dialysis for the rest of their lives; this is called end-stage renal disease (ESRD). ESRD may be caused by a variety of conditions that can impair kidney function, including diabetes, kidney cancer, drug use, high blood pressure, or other kidney problems. Dialysis is not a cure for ESRD, but helps you feel better and live longer.
There are two types of dialysis: hemodialysis and peritoneal dialysis.
PARTS OF THE BODY INVOLVED
Hemodialysis: Veins in the arm, leg, or neck
Peritoneal dialysis: Abdomen
REASONS FOR PROCEDURE
The purpose of dialysis is to help keep the body's chemicals in balance, which the kidneys do when they are healthy. The main functions of dialysis are:
- Removing waste and excess fluid from the blood to prevent build-up
- Controlling blood pressure
- Keeping a safe level of chemicals in the body, such as potassium, sodium, and chloride
Dialysis may also be done to quickly remove toxins from the bloodstream, in cases of poisoning or drug overdose.
RISK FACTORS FOR COMPLICATIONS DURING THE PROCEDURE
Hemodialysis: Heart problems
- Adhesions or significant abdominal scar tissue
- Infection of the peritoneum (lining of the abdominal cavity)
- Abdominal hernia
- Abdominal defects
WHAT TO EXPECT
Prior to Procedure
- Weight, blood pressure, and temperature are taken
- Topical anesthetic (a pain numbing medicine) is applied to the arm for needle insertion
- Heparin (a medication that prevents blood clotting) is given
Peritoneal dialysis: Before the first treatment, the physician places a small, soft tube (approximately 24 inches long) in the abdomen, which remains there permanently. A portion of the tube remains outside the body for use in the peritoneal dialysis process. It is important to keep this access clean and dry to prevent infection.
Anesthesia - For hemodialysis, topical anesthetic
DESCRIPTION OF THE PROCEDURE
Hemodialysis: An artificial kidney machine, called a dialyzer, filters the blood, and returns the cleaned blood to your body. You are connected to the dialyzer via tubes that are inserted into a vein in your arm, leg, or occasionally, neck. If hemodialysis is being done as a temporary measure, then the catheter is likely to be inserted through the neck vein. If hemodialysis is going to be done regularly, then an access site called a fistula or shunt may be surgically created in one of your veins.
Hemodialysis is usually done at a dialysis center or hospital, by trained technicians or nurses, or may be done at home with assistance. Hemodialysis is usually done three times a week and each treatment lasts from two to four hours.
Peritoneal dialysis: Instead of using a machine, this type of dialysis uses the abdominal lining, called the peritoneal membrane, to filter blood. A cleansing solution, called a dialysate, is infused through a tube inserted into your abdomen. Long-term peritoneal dialysis may require the surgical creation of a port in the abdomen through which this dialysate can be infused. Fluid, wastes, and chemicals pass from the tiny blood vessels in the peritoneal membrane into the dialysate, which is then drained after several hours. New dialysate can then be added to repeat the process.
THERE ARE THREE TYPES OF PERITONEAL DIALYSIS:
- Continuous ambulatory peritoneal dialysis (CAPD): This is the most common type of peritoneal dialysis. A bag of dialysate is infused into the abdomen through a catheter, remains there for 3-6 hours, and is then drained. You then refill your abdomen with fresh solution through the catheter. This way your blood is always being cleaned. No machine is required, and the empty plastic bag may be hidden under clothing.
- Continuous cyclical peritoneal dialysis (CCPD): Fluid exchanges in this procedure are done by machine, usually at night while sleeping.
- Intermittent peritoneal dialysis (IPD): Uses the same type of machine as CCPD, but requires assistance and is usually done at a hospital or center. It often takes longer than CCPD.
After Procedure - Once blood pressure is stable, you may resume everyday activities.
How Long Will It Take? The time needed for dialysis depends on a few factors:
- How much kidney function you have
- How much fluid weight gain has occurred since the last treatment
- Amount of waste in the body
- Body size
- Level of minerals in your body such as sodium, potassium, and chloride
- Dialysis method used
The approximate time and frequency of each method: