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:
Whole blood. This is the most common type of blood donation, during which approximately a pint of whole blood is donated. The blood is then separated into its components — red cells, plasma, platelets.
Platelets. This type of donation uses a process called apheresis. During apheresis, the donor is hooked up to a machine that collects the platelets and some of the plasma, and then returns the rest of the blood to the donor.
Plasma. Plasma may be collected simultaneously with a platelet donation, or it may be collected without collecting platelets during an apheresis donation.
Double red cells. Double red cell donation is also done using apheresis. In this case, only the red cells are collected.

RISKS
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

To be eligible to donate whole blood, platelets or plasma, you must be:

In good health.

At least 17 years old — the minimum age varies by state, with some states allowing 16-year-olds to donate with parent permission; there’s no upper age limit.

At least 110 pounds.

Able to pass the physical and health history assessments.

The eligibility requirements are slightly different for double red cell donation. Check with your local donor center for specifics.

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 you must not take aspirin for two days prior to donating. Otherwise, you can take your normal medications as prescribed.

Results
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.

G Mohan.