Understanding Therapeutic Plasma Exchange (TPE)
Therapeutic plasma exchange (TPE) is a treatment that removes plasma from your blood. The removed plasma is then replaced with a substitute. Plasma is the liquid part of blood. It helps carry blood cells and other substances all over your body. With certain diseases, plasma can contain an abnormal substance that may trigger symptoms. TPE helps remove this abnormal substance and ease symptoms. TPE can also help you better fight your disease. TPE is also known as plasmapheresis.
Why TPE is done
TPE is most often used to treat certain blood, nervous system, or autoimmune diseases. Examples are:
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Thrombotic thrombocytopenic purpura (TTP)
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Guillain-Barré syndrome
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Certain types of multiple sclerosis
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Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP)
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Lambert-Eaton syndrome
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Myasthenia gravis
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Some diseases of the kidney such as Goodpasture syndrome
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Waldenström macroglobulinemia. This is a rare type of non-Hodgkin lymphoma.
Used alone, TPE can't cure these diseases. But it may help slow their progress and ease symptoms. When used with other treatments, TPE may increase your chances of fighting the disease.
How TPE is done
TPE uses a special machine to separate blood into its different parts. It then removes and replaces most of the plasma. You often need more than one treatment. You and your healthcare provider will discuss the schedule for your treatment in advance. Each plasma exchange takes about 2 to 4 hours.
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An IV (intravenous) needle is put into a vein in each arm as an access point. In some cases, the healthcare provider may use a large vein in your shoulder or groin instead. Tubing connects the access point or points to the exchange machine.
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Your blood flows through tubing to the machine. Before the blood reaches the machine, medicines are added that prevent the blood from forming clots. These medicines are called anticoagulants.
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The machine separates blood into its different parts. It then removes the plasma.
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The machine adds a plasma substitute to the remaining blood. This may be a replacement fluid that contains saline and albumin. Or it may be plasma from a human donor.
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The blood containing the new plasma returns to you through the tubing.
Risks of TPE
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Low blood pressure
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Shortness of breath
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Metabolic alkalosis. This can cause a headache or seizures.
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Bleeding
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Higher risk for infection because your normal immune system proteins (antibodies) have been removed
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Too little calcium in the blood (hypocalcemia)
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Too little potassium in the blood (hypokalemia), when nonplasma replacement fluid is used
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Allergic reaction or disease transmission when donor plasma is used. Examples are hives or anaphylactic reaction.