Each meets a different and very important medical need. When you make a pheresis donation, you give only one part of the blood, most often platelets, but sometimes granulocytes, infection-fighting white cells.
Platelets are cell fragments in the bloodstream that enable blood to clot.
Cancer and chemotherapy treatments can affect the body's ability to produce platelets. Patients with leukemia, aplastic anemia, those receiving chemotherapy or undergoing bone marrow transplants must rely on platelets donated by healthy volunteers to prevent bleeding episodes that can be life-threatening. Once donated, this living gift must be transfused within five days. On occasion, donors are also needed to give plasma or infection-fighting white cells called granulocytes. It takes approximately 5 whole blood donations to yield as many platelets as one Pheresis donation.