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Platelets are blood cells that start the clotting process.  Platelet transfusions are used to support patients having chemotherapy for leukemia or cancer, and for aplastic anemia and bone marrow transplant patients. Platelets also are used during and after surgery to help stop bleeding and by trauma patients.

Platelets can only be stored for five days, so there is a continuous need for platelet donations, particularly before holiday weekends.

Platelets can be made from whole blood donations, but it takes 4 to 8 pints of whole blood to yield one platelet transfusion. Instead, at NorthShore University HealthSystem we try to use only ‘Single-Donor-Platelets’, which are made by a process called 'apheresis' (A-fur-E-sis). It only takes one apheresis donation to make an entire platelet transfusion, so the patient has a lower risk of many complications of transfusion.

In apheresis, blood is drawn into a machine called a blood cell separator. In the sterile tubing and bags of the machine the donor’s blood is separated into platelets, red blood cells, and plasma.  The machine then returns the plasma and red blood cells to the donor, only retaining the platelets for transfusion.  Because most of the donor’s iron is in the red cells, as many as 24 platelet donations can be made in a year.

Donor criteria are essentially the same as for whole blood donation.

Depending on your weight and height, the apheresis donation process will take approximately 90 minutes. You may watch television or videotapes or simply sit back and relax while helping to save a life.