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General Information Leaflet 5

Plasmapheresis is a procedure in which blood is separated into cells and plasma. The process is often called plasma exchange. The exchange technique separates and removes from the blood stream the plasma (which contains antibodies) and replaces it with normal plasma protein. In some illnesses the body produces antibodies which attack the body itself; these are known as auto-immune diseases. Research tells us that Myasthenia Gravis is an auto-immune disease. During plasma exchange the amount of antibodies in the blood is reduced.

Why am I having plasmapheresis?

Plasmapheresis may have been recommended for several reasons:

  1. To stabilise a rapid decrease in muscle power.

  2. To reduce moderate to severe muscle weakness before thymectomy.

  3. If the current forms of therapy are not providing the expected degree of control of the disease, plasmapheresis may be added to your present treatment.

What are the possible side effects?

Plasmapheresis is a relatively safe procedure and constant monitoring during treatment allows the measurable benefits to out-weigh the risks. However, you may experience and will be instructed to report any signs of numbness, tingling associated with the mouth, eyes, fingers or toes and leg cramps, dizziness and mental confusion which may indicate a low blood calcium or potassium level. You may feel very tired, especially in the second or third day of a course of treatment.

How is access to the blood gained?

A tube called a cannula is inserted into the large vein in the groin under a local anaesthetic. It is stitched into place and remains there until the course of the exchange is complete. The procedure is uncomfortable but not painful.

How long is the treatment?

The amount of plasma that is exchanged is calculated according to your body weight, so could take 2 - 5 hours. The length of a treatment session will vary according to the individual need and will be discussed by your physician. However, it usually takes place every day for 5 days - Monday to Friday. During the exchange you will lie in bed, but for the rest of the day, you will be able to walk around.

What special considerations or helpful hints should I be aware of?

  1. Most importantly, plasmapheresis does not cure Myasthenia Gravis. Its purpose is to temporarily reduce the level of circuiting antibodies that attack the neuromuscular junction. It does not prevent the production of more antibodies. Therefore, in addition to a series of treatments, the patient may be given an immunosuppressive drug to help reduce the production of the antibodies.

  2. You need to be aware that it will be necessary to be fairly still for about 2 - 3 hours. It is advisable to eat a meal before the treatment and also to empty your bladder immediately prior to the start of the procedure. Some patients tend to feel quite exhausted after the treatment.

  3. Whilst the cannula is in place, you cannot bath or shower. Neither can you bath for a minimum of 48 hours after the cannula is removed. During the exchange, it is recommended that you wear loose clothing, e.g. tracksuit, night-dress, pyjamas etc.

  4. Unfortunately, not all patients are improved by this treatment. If improvement does occur, it might be a week or more before the benefits become apparent to you. Some patients need more than one course of treatment, but this will usually be several weeks later.

  5. Often fearfulness about the procedure, especially during the first few treatments, can produce some unusual sensations that will go away once you become more comfortable with the treatment.

The Association does its best to ensure that the information contained in this leaflet is complete and up to date at the time of publication, but cannot accept any legal liability whether for any inaccuracy or otherwise.

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Updated 12-Oct-2009
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