Platelets When your marrow can't produce enough platelets on its own, a platelet transfusion might be necessary to prevent bleeding. Moderate drops in the platelet count do not need treatment. But very low counts—less than 10,000 or 20,000 without bleeding, a little higher with—will require platelet transfusions, often every two to three days.
At least 70 percent of patients who get repeated platelet transfusions will make antibodies to foreign platelet antigens , making the transfusions less and less effective. Blood banks can solve this problem by providing platelets that have the correct HLA type and by doing many cross-matches with donor platelets.
The Apheresis Technique Modern cancer treatment has led to such a voracious need for platelets that the need cannot be met just by making a platelet component from each whole blood donation. So blood banks have turned to a procedure known as apheresis. In this process, a donor's blood is taken from a vein, passed through an apheresis (or separating) device and returned to the donor through another vein. The device skims off and saves the blood platelets while the red blood cells and plasma are returned. When patients no longer respond to the platelets of random donors, family members are often asked to donate platelets by apheresis, since they are much more likely than a random donor to have the same platelet antigens as the patient.
