During the Blood Donation Procedure
You lie or sit in a reclining chair with your arm extended on an armrest. If you have a preference for which arm or vein is used, tell the person who is collecting your blood. A blood pressure cuff or tourniquet is placed around your upper arm to fill your veins with more blood. This makes the veins easier to see and easier to insert the needle into. It also helps fill the blood bag more quickly. Then the skin on the inside of your elbow is cleaned.
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. First, blood is collected into tubes for testing. Then blood is allowed to fill the bag, about a pint (about half a liter). The needle is usually in place about 10 minutes. When your donation is finished, 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 becoming increasingly common is apheresis. During apheresis, you are hooked up to a machine that can collect and separate different parts of your blood, such as red cells, plasma and platelets. This process allows more of a single component to be collected. It takes longer than standard blood donation — typically up to two hours.