Once you have donated blood, blood centers begin a rigorous process to ensure that your donation is made ready for a recipient in need.
If your blood has been collected by the American Red Cross, for example, it is sent to a Red Cross testing and processing facility. Each whole blood donation is typically separated into three components: red cells, platelets, and plasma.
Red cells, which carry oxygen, will help patients who are anemic due to blood loss. Usually these must be transfused within 42 days, unless frozen.
Platelets are cell fragments needed by cancer and other patients who may experience bleeding because they are unable to produce enough platelets on their own. These can only be stored for five days.
Plasma is the liquid portion of the blood. It carries nutrients, removes waste, transports antibodies, and provides coagulation factors to help the blood clot. Plasma may be frozen for transfusion, frozen for storage, or it can be used to extract cryoprecipitate, a substance rich in Factor VIII -- which is needed by patients with classic hemophilia.
Splitting your blood donation into these components means that your single donation has the potential to save as many as three lives!
As part of the donation process, four sample tubes of blood are collected, labeled, and sent to one of our nine state-of-the-art National Testing Laboratories. Our laboratory technicians determine your blood type (A, B, AB, or O) and Rh factor (positive or negative). They also perform up to 12 different tests on each sample of blood. Every unit of blood is screened for infectious diseases such as HIV, syphilis, and hepatitis B and C, as well as for unexpected antibodies that might cause a transfusion reaction in some people.
Each American Red Cross blood donation also undergoes nucleic acid testing (NAT), a highly sensitive testing method to detect both HIV-1 and hepatitis C before the body has begun to produce antibodies.
The test results are then sent via computer to the facility where your blood is being stored. Your unit of blood is tracked by the bar code placed on the bag and the Blood Donation Record when you came to donate blood. By electronically reading the barcode on the bag, the computer will print test results and a label with the blood type for that donation. This computerized process helps us diminish human error and enables us to track each unit of blood.
Each unit of blood is kept at the appropriate temperature until it needs to be shipped to a hospital. Many hospitals receive routine shipments of blood, but Red Cross distribution centers are staffed 24 hours a day in order to meet emergency needs. At the hospital, blood components are cross-matched with patients' blood. A patient may receive your blood donation only 48 hours after your donated it!
Every two seconds, someone in this country needs blood. Volunteer blood donations help patients being treated for accidents, routine surgeries, and serious diseases such as leukemia, lymphoma and other cancers, heart disease, sickle cell anemia, and hemophilia.
To schedule a blood donation appointment, call the Red Cross at 1-800-GIVE-LIFE or donate to an independent blood center by calling 1-888-BLOOD-88.
Together, we can save a life.
Dr. Jerry Squires, MD, PhD
American Red Cross
Vice President and Chief Scientific Officer
Photos: Woman donating blood and blood storage refrigerator, courtesy of the National Library of Medicine.