Dialysis FAQs

What is dialysis?

Dialysis is a process that substitutes for kidney function when the normal operation of the kidneys is interrupted. In a healthy body, the kidneys serve to regulate fluid levels in the body, filter waste products and control urination. Dialysis performs these functions when the kidneys fail due to disease or injury and the resultant buildup of waste products in the body threatens to cause illness.

What are the reasons for dialysis?

Since the kidneys are essential organs, when kidney failure occurs the patient requires dialysis. There are many reasons for kidney failure. These include diabetes, hypertension and polycystic kidney disease. The kidneys may also shut down after a heart attack or severe injury or as a result of surgery.

What are the different kinds of dialysis?

There are two major types of dialysis:


This is a procedure in which a dialysis machine is used to filter the blood. Hemodialysis is administered by health care professionals in a hospital or dialysis. It takes less time and is undergone less frequently than peritoneal dialysis. Because hemodialysis is administered to patients in a group setting, there may be the advantage of emotional support. With hemodialysis there is a risk of low blood pressure, blood clot or infection, but. because it is performed by medical professionals, there are medical safeguards in place.

Peritoneal Dialysis

In this process, the body's own tissues are used to flush waste from the abdominal cavity through the use of injected fluid. Peritoneal dialysis is self-administered by the patient through a catheter that remains in the abdomen. It may be performed in any clean location in the home or during travel. It may also be possible for peritoneal dialysis to be administered during sleep. This procedure has the advantage of requiring fewer dietary and fluid restrictions and it does not make use of needles. Peritoneal dialysis, however, be difficult for some patients to administer and carries a risk of peritonitis, a serious abdominal infection.

What happens during dialysis?

During dialysis, blood is removed from a vein the patient's arm or leg, circulated through a filtering machine, and returned to the body through an artery. Since veins tend to have weak blood flow, the doctor often connects one of the patient's arteries to the vein being used for dialysis. This increases blood flow and strengthens the vein. The artery-to vein connection, known as arteriovenous connection or AV, can be created either through the use of a graft, or artificial tube, or through the creation of a fistula, a direct surgical connection of one blood vessel to another.

What are the differences between grafts and fistulas?

Though fistulas take 2 to 6 weeks to mature, while grafts are ready for use in only two to six weeks, doctors prefer to use fistulas which are stronger than grafts and have a lower risk of infection. The use of a graft, however, is indicated when the patient has small, blocked or scarred veins.

What are the possible complications associated with dialysis?

While dialysis is a safe procedure, there are various complications and risks associated it. Some are uncomfortable but not serious, such as itching, sleep problems, joint pain and muscle cramps. Others are more dangerous, such as elevated or low blood pressure, infection at the site, pericarditis, anemia, and elevated potassium levels.

Should special care be taken by a patient undergoing dialysis?

Yes. It is extremely important for the patient and health care professionals involved to avoid possible infection by hand washing, the use of surgical masks and antiseptic wipes, and inspection of supplies to ensure cleanliness. It is also necessary for the patient to eat a special diet high in protein and low in potassium and phosphorous, and to monitor fluid intake carefully.

Is dialysis ever temporary?

Yes. There are several circumstances in which dialysis is only needed for a certain period of time until kidney function returns. If dialysis is being used for kidney failure, however, it will be employed permanently or until the patient receives a kidney transplant.

Other than dialysis, is there any other effective treatment for kidney failure?

The only effective treatment for kidney failure other than hemodialysis or peritoneal dialysis is for the patient to receive a kidney transplant.

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