Buy Our Book | Home | Contact Us | Links




New Documents ABO Blood Group System Acute Hemolytic Transfusion Reaction Allergic Reactions Anaphylactic Reactions Antibody Adsorption Procedures Antibody Identification Apheresis Autologous Blood Donation Blood Infusion Blood Salvage CMV Negative Blood Components Compatibility Testing Cord Blood Direct Antiglobulin Testing Cryoprecipitate Delayed Hemolytic Transfusion Reaction Direct Antiglobulin Test Directed Blood Donations Drug Induced Thrombocytopenia Febrile Nonhemolytic Reactions Fetal Maternal Hemorrhage Hemophilia A Hemophilia B Heparin Induced Thrombocyopenia Previous Documents ABO Blood Group System ABO Mismatched Allogeneic Transplants Albumin Autoimmune Hemolytic Guidelines Blood Administration Blood Component Transfusion Guidelines Blood Donation CMV Negative Blood Components Compatibility Testing Cryoprecipitate Factor IX Complex Factor VIIa Factor VIII Concentrate Factor VIII Inhibitors Fresh Frozen Plasma Granulocyte Transfusion Hemolysis Following Allogeneic BMT Informed Consent Irradiated Blood Components Leukocyte Reduced Red Cells & Platelets Massive Transfusion Neonatal Alloimmune Thrombocytopenia Nitric Oxide Banked Blood Other Blood Group Systems Pediatric & Neonatal Transfusion Practices Platelet Transfusion Prenatal & Perinatal Immunohematologic Testing RBC Transfusion Trigger Red Blood Cell Transfusion Rh Blood Group System RhIG for HDN Prevention RhIG for Treatment of ITP Saline Washed Red Blood Cells Sickle Cell Disease Transfusion Therapeutic Apheresis Thrombotic Thrombocytopenic Purpura Transfusion Reactions Transfusion Related Acute Lung Injury Trypanosoma Cruzi Donor Screening Umbilical Cord Blood Stem Cells von Willebrands Disease Warm Autoimmune Hemolytic Anemia

Apheresis

Apheresis employs an automated cell separator that harvests a specific blood component by centrifugal force. It involves a multi-step process that includes:

Removal of whole blood from a donor or patient
Separation of whole blood into components such as red cells, plasma, platelets or white cells
Retention of the specific component needed
Return of the unneeded recombined components to the donor

Apheresis takes 1 to 2 hours to complete. During this time the donor or patient is connected by 1 or 2 IV lines to a sterile set of collecting and infusion bags. This closed system eliminates the risks of bacterial contamination and of returning the wrong blood to the donor.

Red cells may be collected by apheresis. Two allogeneic or autologous red cell units may be removed every 16 weeks. Volume depletion is minimized with saline infusion and the procedure is limited to individuals who are larger and have higher hematocrits (>40%) than current minimum standards for whole blood donors.

Plasmapheresis involves the separation of fresh plasma from 1.0 to 1.2 L of whole blood from a single donor, depending on the donor's weight. This component is usually processed into Fresh Frozen Plasma or Cryoprecipitate. Its larger volume (usually equivalent to 2 units FFP) can be used by one patient to reduce donor exposures or can be aliquoted to benefit several patients.

Plateletpheresis is the collection of platelets from a single donor and is often called single donor platelets. Donors should not take aspirin within 36 hours of donation. Blood pumped from one arm passes through a blood cell separator centrifugation system that collects platelets and returns plasma and red cells to the donor's other arm. Between 4000 and 5000 mL of blood are processed over 1.5 to 2 hours. A single donor platelet concentrate contains >3.0 X 1011 platelets suspended in approximately 200 mL of plasma, which is the equivalent of 6 to 8 random donor platelet concentrates. They can be stored up to 5 days at room temperature.

Because red cells and plasma are returned, a plateletpheresis donor can give more frequently than a whole blood donor; once or twice a week. This procedure is ideal for collecting platelets from special donors such as directed donor, platelet crossmatch compatible or HLA-matched.

Single donor apheresis platelets contain fewer than 5 x 106 white blood cells and are considered to be leukocyte reduced. Additional leukocyte reduction filtration is not necessary. Rh negative patients do not need Rh immune globulin after transfusion of Rh positive apheresis platelets because they contain so few red blood cells.