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What are platelets?

Platelets are irregularly shaped, colorless bodies that are present in the blood. Platelets help form blood clots to stop bleeding. The average lifespan of a platelet is about five days.

Who needs platelets?

Cancer, cardiac, and transplant patients need platelet transfusions to live. Children undergoing treatment for cancer and those receiving bone marrow transplants use most of the platelets that are collected at Boston Children's Hospital. The chemotherapy that eliminates cancer cells also eliminates the healthy cells in the bone marrow, including those responsible for making platelets and red blood cells. As a result, children need frequent transfusions of red blood cells to carry oxygen AND platelets to prevent serious and life-threatening bleeding episodes during their cancer treatment. Children undergoing a bone marrow transplant may require more than one bag of platelets EVERY day as it takes about 30 days for the new donor bone marrow to grow and start working.

How are platelets collected?

Through a single sterile needle, some of your blood is removed and passed through a platelet pheresis machine. The platelet pheresis machine separates the platelet/plasma from your blood then returns your blood back to you through the same needle. Donating platelets takes 60 to 120 minutes depending on your size and platelet count, and you may be able to donate up to 24 times a year. During your donation you can read, listen to music, watch TV or a DVD, or just sit back and relax.

How do I prepare?

Prior to donating: Do not take aspirin or medications containing aspirin for 48 hours before your donation.

On the day of donation:

  • Make sure you are well hydrated.
  • Make sure you eat a meal prior to donating.
  • Bring a photo ID with you.

To make an appointment to donate, please visit https://www.childrenshospital.org/halfpints.

What are the ideal blood types?

Donors with all blood types can donate platelets; those in most demand are A+, B+, AB+ and AB-.