What is involved in donating blood?

Each year, about 12 million to 14 million units (pints) of blood are donated in the United States. Typically, a blood donor must be at least 17 years old, healthy and more than 110 pounds.

Before donating blood, the donor is given an information pamphlet . A health history is taken to make sure the donor has not been exposed to diseases that can be transmitted through blood, and to determine if donating blood is safe for his or her own health. A donor's temperature, pulse, blood pressure and weight are measured. A few drops of blood are taken to make sure the donor is not anemic. Once the needle has been placed, it usually takes less than 10 minutes to remove a unit of blood. Sterile, single-use equipment is used. Therefore, donors have no danger of infection. Donors should drink plenty of fluids and avoid exercise that day. Donors can give blood every eight weeks.

The individual units of blood can be separated into several components. Each component can be given to someone with a specific need. Therefore, a single unit can help many people. The various components include packed red or white blood cells and many others.

Plasma, for example, can be thawed and transfused to treat bleeding disorders if clotting factors are missing.

Platelets can be transfused into people with low platelet count (thrombocytopenia) or people with abnormally functioning platelets.

Albumin, which makes up 60 percent of the protein in plasma, is used when blood volume needs to be increased especially when fluids have not worked. This is used for severe bleeding, liver failure and severe burns.

Immunoglobulins are given to people who have been exposed to a certain disease including rabies, tetanus or hepatitis to help prevent those diseases.

Factor VIII concentrate and cryoprecipitate are used for hemophilia A (classic hemophilia). This disease is caused by a deficiency of factor VIII.

Factor IX concentrate is used for hemophilia B ("Christmas disease"). This disease is caused by a deficiency of clotting factor IX.

Donating a unit of blood takes about 45 to 60 minutes. Medical equipment is sterile, used only once, and then discarded. The actual donation process works like this:
1) You will complete donor registration, which includes your name, address, phone number, donor identification number (if you have one), and other related information.
2) You will be asked to show your donor card or other identification.
3) You will be asked some questions about your health, travel history, and lifestyle or risk behaviors. All information is confidential.
4) You will receive a mini “health exam”, including checks for blood pressure, temperature, and pulse. In addition, a drop of blood will be obtained from your finger to make sure that you have enough red blood cells to safely donate.
5) You will proceed to a donor bed where your arm will be cleaned with antiseptic. If you are allergic to iodine, be sure to tell the phlebotomist so an alternate antiseptic may be used.
6) You will have a blood unit and blood specimens drawn.
7) You will receive snacks and beverages while you wait for about 15 minutes after donation. Waiting periods are different in different states.
Donating blood is a simple process. Your gift of blood may help three people or more. Donated red blood cells have a shelf-life of up to 42 days. A healthy donor may donate every 56 days.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.