It is very important to have a fair knowledge about the blood groups and transfusions so as to avoid fatality. This article will help you to know about your blood group and their compatibility with other blood groups which will further help you in blood transfusions.
At the time of injury or blood disorders, the person is supplied with blood which is given by the blood donor. Unfortunately, everyone can not donate blood to everyone. There are some criteria which should be fulfilled. Hence, it becomes very important for a person to know about blood groups and transfusions as this information will help him at the time of emergency.
Human Blood Constituents
Human blood has four main constituents red blood cells, white blood cells, platelets and plasma. Let’s find out the difference between them.
- Red Blood Cells : Red blood cells are responsible for the transport of oxygen to different parts of the body and removing carbon dioxide from the body. This is done by the hemoglobin content in the red blood cells. Hemoglobin attaches to the oxygen and carries on the process. Red blood cells hold 40-45% of total volume of the blood. Their life cycle is of 120 days after which they break down and new blood cells are formed by that time.
- White Blood Cells : White blood cells are the backbone of the immune system. They help our body to fight with various diseases, infections, etc., and save us from getting affected. It holds less than 1% of the total volume of the blood and its life may vary from person to person.
- Platelets : Platelets help in the blood flow from the injury as they are responsible for the clotting of blood. They are formed in the bone marrow. Platelets hold about 5% of the blood volume and have a life span of 5 to 9 days.
- Plasma : Plasma is a yellow colored transparent fluid which hold 50-55% of the total blood volume. It constitutes protein, water, hormones, vitamins, cholesterol, etc.
Human Blood Groups
You will be surprised to know that human beings have 8 different types of blood groups. This is the reason why the blood cannot be transfused to anyone without matching it. But what is the basis of blood groups differentiation? Well, blood groups are differentiated on the basis of protein which are present on the surface of the blood cells. These proteins are present in the form of antigens and antibodies. There are four blood types A, B, AB and O. For example, if the person has A blood group, then he will have A antigens and B antibodies in his blood. The antigens are attached to the blood cell and the antibodies are found in the blood plasma. So, if a person with A blood group is given B blood group then the antibodies of A blood group will kill the cells of B blood group which will lead to blood agglutination.
Apart from this, there is one more factor which differentiate blood groups, it is Rh factor. Rh is also an antigen which is found on the surface of the blood cell. Maximum people have this antigen and hence they are called Rh+ and the people who lack this antigen are called Rh–. So if a person has A and Rh antigen both, then the person is called A Rh+. Rare blood types or groups does not consists of Rh factors, they are A Rh–, B Rh– and O Rh–. Following list will help you to understand various blood groups in details.
| Blood Group | Antigens | Antibodies |
| A Rh+ | A and Rh | B |
| A Rh– | A | B |
| B Rh+ | B and Rh | A |
| B Rh– | B | A |
| AB Rh+ | A, B and Rh | None |
| AB Rh– | A and B | None but can develop Rh antibodies |
| O Rh+ | Rh | A and B |
| O Rh– | None | A and B. It can develop Rh antibodies too |
Blood Transfusions
Transfusions of blood is a process of blood transfer from donor to the receptor. The blood can be given to the receptor only when they have same blood group. But as we say there are always some exceptions, O Rh– blood group holders can give blood to any of the blood group people, hence they are known as universal donor. Whereas AB Rh+ blood group can receive blood from any donor, hence they are called universal acceptor. Apart from these two, if there is a transfer of unmatched blood to any person, then his antibodies will attack the antigens and will result in agglutination. This can stop the blood flow and the person may die. Hence it is very important to test the blood before the blood transfusion so as to avoid serious consequences. Following is the table which will give you details about which blood group can receive blood from which blood group.
| Blood Group | Can Donate Blood to | Can Receive Blood from |
| A Rh+ | A Rh+ and AB Rh+ | A Rh+, A Rh–, O Rh+ and O Rh– |
| A Rh– | A Rh+, A Rh–, AB Rh+ and AB Rh– | A Rh– and O Rh– |
| B Rh+ | B Rh+ and AB Rh+ | B Rh+, B Rh–, O Rh+ and O Rh– |
| B Rh– | B Rh+, B Rh–, AB Rh+ and AB Rh– | B Rh– and O Rh– |
| AB Rh+ | AB Rh+ | A Rh+, A Rh–, B Rh+, B Rh–, AB Rh+, AB Rh–, O Rh+ and O Rh– |
| AB Rh– | AB Rh+ and AB Rh– | A Rh–, B Rh–, AB Rh– and O Rh– |
| O Rh+ | A Rh+, B Rh+, AB Rh+, O Rh+ | O Rh+ and O Rh– |
| O Rh– | A Rh+, A Rh–, B Rh+, B Rh–, AB Rh+, AB Rh–, O Rh+ and O Rh– | O Rh– |
If you still don’t know which blood group you belong to, then go for a blood test today itself. Be prepared for any emergency and do remember to test the donor’s and receptor’s blood group before donating blood. Never step back from donating blood to the needy.
