Apheresis is a medical procedure that involves the separation of a person’s blood into its individual components. This process uses an external machine to collect specific parts of the blood, while returning the remaining components to the body. It is often performed for various medical purposes, including collecting healthy blood components for donation or removing unhealthy substances from a patient’s bloodstream.
Understanding Apheresis
The fundamental principle of apheresis involves drawing whole blood from an individual and processing it through a specialized apheresis machine. This machine then separates the blood into its various components, such as plasma, platelets, red blood cells, and white blood cells, based on their different densities. The separation typically occurs through centrifugation, where the blood is spun at high speeds. Once separated, the desired blood component is collected by the machine, while the unneeded components are returned to the bloodstream. The remaining blood components are returned to the body, maintaining the individual’s overall blood volume.
Different Applications of Apheresis
Apheresis is utilized for a range of medical purposes, targeting specific blood components for either collection or therapeutic removal. These applications include:
Plasmapheresis involves collecting blood plasma, often used to obtain fresh frozen plasma for transfusions or to remove harmful antibodies in patients with autoimmune disorders or certain neurological conditions.
Plateletpheresis, also known as thrombapheresis, focuses on collecting platelets, which are then used for transfusions to support patients with low platelet counts due to chemotherapy or bleeding disorders.
Leukapheresis is the process of collecting white blood cells, which can be done to obtain hematopoietic stem cells for bone marrow transplants or to reduce dangerously high white blood cell counts in leukemia patients.
Erythrapheresis, or red blood cell apheresis, involves the separation and removal of red blood cells, commonly employed to treat conditions like sickle cell disease by replacing abnormal red blood cells with healthy ones.
Photopheresis is another application where blood is treated with a light-absorbing substance and ultraviolet light before being returned to the body, often used in treating graft-versus-host disease, cutaneous T-cell lymphoma, and organ transplant rejection.
What to Expect During Apheresis
Before apheresis, individuals are typically advised to hydrate well, as this can help with vein access and overall comfort during the procedure. Two intravenous (IV) lines are usually established, one for drawing blood and another for returning the processed blood components. The procedure itself usually takes between two to four hours, depending on the specific type of apheresis and the volume of blood being processed. During this time, the individual will be comfortably reclined while the apheresis machine continuously circulates their blood. After the procedure, individuals are generally encouraged to rest and continue hydrating. Minor side effects such as lightheadedness or fatigue may occur immediately afterward, but these typically resolve quickly.
Safety and Important Considerations
Apheresis procedures are generally considered safe, with medical professionals closely monitoring individuals throughout the process. Minor and temporary side effects can occur, such as bruising or soreness at the needle insertion site. Some individuals may experience a temporary tingling sensation, particularly around the lips or fingertips, which is often due to the anticoagulant used to prevent blood clotting in the machine. These minor effects are typically managed by adjusting the flow rate or administering calcium supplements if needed. For donors, specific eligibility criteria are in place to ensure their well-being and the safety of the collected components. This includes considerations for weight, hemoglobin levels, and recent medical history.