To Help Manage Kidney Failure—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%-90% of their ability to function and will continue dialysis for the rest of their lives (unless a kidney transplant is available and successful). Dialysis is not a cure for ESRD, but helps you feel better and live longer.
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
There are two main types of
: hemodialysis and peritoneal dialysis.
For 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 into your natural vein. If hemodialysis is going to be done regularly, then a vascular access site called a fistula or shunt may be surgically created, usually in your arm or leg.
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 2-4 hours.
Complications from hemodialysis include the following:
- Infections, usually bacterial
- Low blood pressure
- Abnormal heart rhythms
- Bleeding (brain, eyes, abdomen, intestine)
- Air embolus
- Anaphylaxis or severe allergic reaction
Instead of using a machine, peritoneal 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 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.
Complications from peritoneal dialysis include the following:
- Hernias in the abdomen or groin
- High blood sugar levels
- Low level of blood albumin
- Infection, usually bacterial
- Bleeding in the abdomen
- Leakage of fluid from the abdomen
- Weight gain
There are three main 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 you are sleeping.
- Intermittent peritoneal dialysis (IPD)
—This method 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.
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