Platelets are one of the components required to make blood clot. They are approximately one quarter the size of red blood cells and are not, whole cells, but fragile cell fragments.

Platelets originate from giant cells called megakaryocytes, found in bone marrow. As the megakaryocyte matures, small fragments break off and are released into the blood stream. These fragments are called platelets and have a shelf life of only five days meaning that they must be used within 5 days.

Patients with prolonged bleeding associated with some diseases (e.g. cancer) need large quantities of platelets as part of their treatment. In a healthy person, a large number of platelets are manufactured and stored in the body. If an injury or blood loss should occur, the platelets are released and the clotting process is initiated by the platelets.

For instance, when a blood vessel is damaged, platelets first adhere to the rough edges of the injured vessel. They cluster together to plug the hole in the blood vessel wall. If the injury to the blood vessel is large, the platelet plug alone will not stop the bleeding. When the platelets collect at the injury site, they also release several factors that start the complex mechanism of blood clotting. The interaction of the released platelet factors and other plasma protein clotting factors will result in the formation of a blood clot, a stronger patch on the injured site.

Watch the video on platelet donation

Are you a potential platelet donor?

YES! Any healthy individual who meets Canadian Blood Services eligibility criteria can donate platelets.

You must provide proper identification, be at least 17 years old and weigh a minimum of 50kg/110lbs. Those with type O Negative blood are universal red blood cell donors and are encouraged to make blood donations instead as are females with a history of pregnancy.