FACTS ABOUT BLOOD AND BLOOD BANKING

(With inputs from American Association of Blood Banks)

Each donated unit of blood, referred to as whole blood, can be separated into multiple components, such as red blood cells, plasma and platelets. Each component can be generally transfused to a different individual, each with different needs.

The need for blood is great. Accident victims, people undergoing surgery, and patients receiving treatment for leukemia, cancer or other diseases, such as sickle cell disease and thalassemia, all utilize blood.

Who donates blood?

It is typically the humane, service oriented individuals who volunteer to donate blood. There are many social service organisations and institutions who encourage, mobilize and conduct blood donation camps. Relatives and friends of a patient requiring a blood transfusion may wish to help their loved one. Donating blood to replenish the units that were needed is one of the best gifts one can give.

Sometimes, patients scheduled for surgery may be eligible to donate blood for themselves, known as autologous blood donation. In the weeks before non-emergency surgery, an autologous donor may be able to donate blood which will be stored until the surgical procedure.

Where is blood donated?

There are many places where blood donations can be made. There are blood banks who accept blood donation. There are blood donation camps conducted at regular intervals in different parts of the country and collect blood. People can also donate at hospital-based blood banks. Consult the yellow pages to locate a nearby blood bank or hospital to donate.

What are the criteria for blood donation?

To be eligible to donate blood, a person must generally be at least 17 years of age ; be in good health; and weigh at least 50 Kilograms. Most blood banks have no upper age limit. All donors must pass the physical and health history examinations given prior to donation.

Nearly all blood used for transfusion  is drawn from volunteer donors. The donor's body replenishes the fluid lost from donation in 24 hours. It may take up to two months to replace the lost red blood cells. Whole blood can be donated once every eight weeks.

What is Apheresis?

An increasingly common procedure is apheresis, or the process of removing a specific component of the blood, such as platelets, and returning the remaining components, such as red blood cells and plasma, to the donor. This process allows more of one particular part of the blood to be collected than could be separated from a unit of whole blood. Apheresis is also performed to collect plasma (liquid part of the blood) and granulocytes (white blood cells).

The apheresis donation procedure takes longer than whole blood donation. A whole blood donation takes about 20 minutes to collect the blood, while an apheresis donation may take about an hour.

What is the most common blood type?

The approximate distribution of blood types in the  population is as follows. Distribution may be different for specific racial and ethnic groups:

	O   Rh-positive................................ 38 percent

	O   Rh-negative................................  7 percent

	A   Rh-positive................................ 34 percent

	A   Rh-negative................................  6 percent

	B   Rh-positive................................  9 percent

	B   Rh-negative................................  2 percent

	AB  Rh-positive................................  3 percent

	AB  Rh-negative................................  1 percent

In an emergency, anyone can receive type O red blood cells, and type AB individuals can receive red blood cells of any ABO type. Therefore, people with type O blood are known as “universal donors” and those with type AB blood are known as “universal recipients.” In addition, AB plasma donors can give to all blood types.

What tests are performed on donated blood?

After blood is drawn, it is tested for ABO group (blood type) and Rh type (positive or negative), as well as for any unexpected red blood cell antibodies that may cause problems in the recipient. Screening tests are also performed for evidence of donor infection with hepatitis viruses B and C, human immunodeficiency viruses (HIV) 1 and 2, human T-lymphotropic viruses (HTLV) I and II and syphilis. The specific tests performed are listed below:

• Hepatitis B surface antigen (HBsAg)
• Hepatitis B core antibody (anti-HBc)
• Hepatitis C virus antibody (anti-HCV)
• HIV-1 and HIV-2 antibody (anti-HIV-1 and anti-HIV-2)
• HIV p24 antigen
• HTLV-I and HTLV-II antibody (anti-HTLV-I and anti-HTLV-II)
• Serologic test for syphilis

How is blood stored and used?

Each unit of blood is normally separated into several components. Red blood cells may be stored under refrigeration for a maximum of 42 days, or they may be frozen for up to 10 years. Red cells carry oxygen and are commonly used to treat anaemia. Platelets are important in the control of bleeding and are generally used in patients with leukemia and other forms of cancer. Platelets are stored at room temperature and may be kept for a maximum of five days. Granulocytes are sometimes used to fight infections, although their efficacy is not well-established. They must be transfused within 24 hours of donation. Fresh frozen plasma, used to control bleeding due to low levels of some clotting factors, is usually kept in the frozen state for up to one year. Cryoprecipitated AHF, which contains only a few specific clotting factors, is made from fresh frozen plasma and may be stored frozen for up to one year.

Other products manufactured from blood include albumin, immune globulin, specific immune globulins and clotting factor concentrates. These blood products are commonly made by commercial manufacturers.

What fees are associated with blood?

While donated blood is free, there are significant costs associated with collecting, testing, preparing components, storing and shipping blood, recruiting and educating donors and quality assurance. As a result, processing fees are charged to recover costs. Processing fees for the individual blood components vary considerably. Processing fees for one specific component may also vary in different geographic regions. Hospitals charge for any additional testing that may be required, such as the crossmatch, as well as for the administration of the blood.

When are blood donors needed most?

Blood donors are needed throughout the year. The need may be more critical during holidays and festivals as there may be less people available to donate.