Apheresis

Apheresis (say "af-uh-REE-sus") is the process of withdrawing blood, filtering something out of the blood, and then putting the filtered blood back into the body. It has different names depending on what is being filtered from the blood. Some of these names include plasmapheresis (when plasma is removed from the blood) and therapeutic cytapheresis (when abnormal cells are removed from the blood).

It may be used to treat certain blood disorders, cancers, and other diseases. It also may be used to remove harmful things from the blood, such as toxins or extra iron.

Blood is taken by inserting an intravenous (I.V.) needle into a vein. The blood is processed in a machine. Then the blood goes back into the body through another I.V. If it's not possible to use an I.V., a central vascular access device may be used instead. It's a thin, flexible tube that goes into a large vein in the neck or chest.

Your doctor may have you go to the bathroom first. After you're attached to the machine, you can't leave it until the procedure is finished.

You may need only one treatment. Or you may need many treatments over weeks or months. It depends on what type of apheresis is used and what is being treated.