About Your Dialysis Treatment

This information explains dialysis at Memorial Sloan Kettering (MSK).

Your Kidneys and Their Function

Your kidneys are 2 bean-shaped organs that are located in the back of your abdomen (see Figure 1). Some of their functions include:

  • Filtering your blood and removing extra fluids and waste products from your body (see Figure 2).
  • Keeping the fluids in your body balanced.
  • Making a hormone called erythropoietin that helps your body’s bone marrow make red blood cells.
  • Making hormones to maintain blood pressure and helping control calcium levels.
Figure 1. Your kidneys
Figure 2. How kidneys work
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Kidney Failure

Kidney failure happens when your kidneys cannot do their functions and stop working normally.  Kidney failure can occur suddenly (acute) or over a period of years (chronic). With acute kidney failure, the kidneys may start working normally again with up to 3 months of dialysis treatment. Chronic kidney failure is permanent and the kidneys will not start working normally again.

Signs and symptoms of kidney failure

Common signs and symptoms of kidney failure are:

  • Decreased urination
  • Shortness of breath
  • Swelling in the legs, arms, and face

Some people also have nausea, vomiting, loss of appetite, difficulty concentrating, weakness, and fatigue.

Your doctor may also do some blood tests to check your blood urea nitrogen (BUN), creatinine, and potassium levels. These will be higher than normal if you have kidney failure.

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Dialysis is the only treatment for kidney failure. It replaces the work that your kidneys do. Dialysis treats kidney failure by filtering the waste products and extra fluids out of your blood.

Dialysis is done by using a dialysis machine. Your blood travels outside your body through tubes and passes through a filter called a dialyzer on the dialysis machine. The dialyzer functions like your kidneys and cleans your blood. Your cleaned blood is then returned to your body (see Figure 3).

Figure 3. A patient receiving dialysis

Before you start dialysis

Before you start dialysis, you will need to have a central venous catheter (CVC) placed for your treatments. A CVC is a thin, flexible tube that is placed into a large vein in your neck, chest, or groin area (see Figure 4). This allows your blood to travel from your body to the dialyzer to be cleaned and then returned to your body.

Figure 4. A CVC in the chest

Your doctor or nurse will give you more information about having a CVC placed. This catheter may be placed at the bedside or by Interventional Radiology.

What to expect during dialysis

At MSK, only admitted patients (inpatients) can get dialysis. When you are being admitted, tell your doctor or nurse that you are on dialysis.

On the first day of your dialysis treatment, you will be taken to the dialysis treatment room on your hospital bed. Your nephrologist (kidney doctor) will examine you, answer any questions that you may have, and get your consent for the procedure. Your dialysis nurse will check your vital signs (blood pressure, temperature, and pulse) and answer any questions before starting the treatment.

Your nurse will connect your CVC to the dialysis lines. Your blood will flow from your body and into the dialyzer, where waste products and fluids will be removed. Your clean blood will then be returned to your body, and you will be disconnected from the machine. You will be taken back to your room.

During dialysis, most people do not experience any pain or discomfort. You can sleep, watch television, or read during treatment.

Hours and location

At MSK, dialysis is done in 2 treatment rooms within the Intensive Care Unit (ICU). The ICU is located on the 11th floor of the hospital, at 1275 York Avenue. Dialysis is done Monday through Friday from 7:00 am to 5:00 pm, and occasionally on weekends.  Our unit has 24 hour coverage by nurses and a nephrologist.

Please note that food is not allowed in the dialysis area. Visitors are not allowed in the rooms while you are having dialysis.

Timing of dialysis treatments

Your first treatment may last 2 to 3 hours and may be done every day for up to 3 days. This is done so that your body can get used to the process. The following treatments may last 3 to 4 hours, depending on your daily lab results and weight.

Regular treatments are usually done 3 times a week but depending on your individual needs, treatment can be done more often. Your nephrologist will evaluate you daily to see what your dialysis needs are. Your dialysis may take priority at times over your other treatments, because your body needs it in order to function normally.

After your dialysis

A CVC is usually used only for short-term dialysis. Once your doctor feels that your kidneys are functioning normally again, your CVC will be removed. If you need to continue having dialysis after you leave the hospital, your doctor will talk to you about what you will need.

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Contact Information

If you have any questions or concerns, please call the dialysis unit at 212-639-6836. You can reach a staff member Monday through Friday from 7:00 am to 5:00 pm. After 5:00 pm, during the weekend, and on holidays, please call 212-639-2000 and ask for the fellow on call for the renal service.

You can also call the renal office at 212-639-8212.

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