Blood donation is a voluntary procedure. You agree to have blood drawn so that it can be given to someone who needs a blood transfusion. Millions of people need blood transfusions each year. Some may need blood during surgery. Others depend on it after an accident or because they have a disease that requires blood components. Blood donation makes all of this possible.
There are several types of blood donation:
To be eligible to donate whole blood, platelets or plasma, you must be:
The eligibility requirements are slightly different for double red cell donation. Check with your local donor center for specifics.
Blood donation is safe. New, sterile disposable equipment is used for each donor, so there's no risk of contracting a bloodborne infection by donating blood.
If you're a healthy adult, you can usually donate a pint of blood without endangering your health. Within 24 hours of a blood donation, your body replaces the lost fluids. And after several weeks, your body replaces the lost red blood cells.
How you prepare
Maintain a healthy diet that includes iron-rich foods, such as spinach, red meat, fish, poultry, beans, iron-fortified cereals and raisins. Get plenty of sleep the night before you plan to donate.
Eat a healthy meal before your donation. Avoid fatty foods, such as hamburgers, fries or ice cream before donating. Tests for infections done on all donated blood can be affected by fats that appear in your blood for several hours after eating fatty foods. Drink an extra 16 ounces (473 milliliters) of water and other fluids before the donation.
If you are a platelet donor, remember that your system must be free of aspirin for two days prior to donation. Otherwise, you can take your normal medications as prescribed.
What you can expect
Before you can donate blood, you will be asked to fill out a confidential medical history that includes direct questions about behaviors known to carry a higher risk of bloodborne infections — infections that are transmitted through the blood. All of the information from this evaluation is kept strictly confidential.
Because of the risk of bloodborne infections, not everyone can donate blood. The following high-risk groups are not eligible to donate blood:
You will also have a brief physical examination, which includes checking your blood pressure, pulse and temperature. A small sample of blood is taken from a finger prick and is used to check your hemoglobin level, the oxygen-carrying component of your blood. If your hemoglobin concentration is normal and you've met all the other screening requirements, you can donate blood.
During the procedure
A new, sterile needle is inserted into a vein in your arm. This needle is attached to a thin, plastic tube and a blood bag. Once the needle is in place, you tighten your fist several times to help the blood flow from the vein. Blood initially is collected into tubes for testing. When these have been collected, blood is allowed to fill the bag, about a pint. The needle is usually in place about 10 minutes. When complete, the needle is removed, a small bandage is placed on the needle site and a dressing is wrapped around your arm.
Another method of donating blood is becoming increasingly common and is known as apheresis. During apheresis, blood is drawn from one arm and pumped through a machine that separates out a specific component, such as platelets. The rest of the blood is then returned through a vein in your other arm. This process allows more of a single component to be collected. However, it takes longer than standard blood donation — typically one to two hours.
After the procedure
Contact the blood donor center or your doctor if you:
Your blood will be tested to determine your blood type — classified as A, B, AB or O — and your Rh factor. The Rh factor refers to the presence or absence of a specific antigen, a substance capable of stimulating an immune response, in the blood. So you're either Rh positive or Rh negative, meaning you carry the antigen or you don't. This information is important because your blood type and Rh factor must be compatible with the blood type and Rh factor of the person receiving your blood.
Your blood will also be tested for bloodborne diseases, such as hepatitis, HIV and syphilis. If these tests are negative, the blood is distributed for use in hospitals and clinics. If any of these tests are positive, the blood bank notifies you, and your blood is discarded and not used.
Last Updated: 2011-05-26
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