Plasma exchange (plasmapheresis) is a procedure done to remove part of a person's blood that may be the cause of a disease. In plasma exchange, whole blood is withdrawn and the liquid portion (plasma) is separated from the red and white blood cells and replaced with a saline and albumin (protein) solution.

Plasma exchange requires access to a large vein. The procedure may be more dangerous if it is performed on older adults or people with heart disease.