Apheresis (also called hemapheresis, pheresis) is a medical procedure during which whole blood is removed from a donor or patient, separated into individual components so that one particular component can be removed and re-introduced back into the bloodstream of the patient or donor with the remaining blood components.
It is used for the collection of donor blood components and for the treatment of certain medical conditions in which a part of the blood that contains disease-provoking elements is removed, such as plasma, leukocytes, lymphocytes, red blood cells, and platelets.
During the apheresis procedure, total plasma exchange (removal of plasma and replacement with fresh frozen plasma) can also be performed.
Apheresis can be used in a therapeutic manner and individualized regarding the frequency of treatments, the volume of blood or components to be removed, and the type of solution used for volume replacement.
Also, it can be effective in certain cases of severe rheumatoid arthritis, severe vasculitis, systemic lupus with life-threatening complications, polymyositis or dermatomyositis, rapidly progressive glomerulonephritis, chronic autoimmune polyneuropathy, and in cases of solid organ transplantation with a high risk of antibody-mediated rejection of the transplant.
During the procedure, the blood in the patient/donor's veins is connected through tubing to a machine that separates the blood components. After the separation, the desired component of the blood is removed, while the remainder of the blood components is reinfused back into the patient.
The procedure takes about two hours or slightly longer than a conventional blood donation and it is painless.
The procedure cannot be performed if a patient has an active infection, unstable heart or lung conditions, severely low white blood cell or platelet counts, a bleeding tendency, or a significantly low blood pressure.
Minor complications of donor apheresis can include bleeding at the donation site and feelings of lightheadedness that usually resolve quickly. Serious complications of donor apheresis are rare.
More serious complications can occur when apheresis is used for a treatment: bleeding and a tendency to bleed when clotting factors are removed, low blood pressure when fluids are removed, muscle cramping when blood calcium is low and other electrolytes are imbalanced and infection and a tendency toward infection when antibodies are removed.