
Blood type test is a test done to know one’s blood type. There are two types of blood type test, i.e. ABO system and Rhesus system (RH).
Blood type tests are not only for blood transfusions. There are various other functions of knowing the blood type that we have. Knowing the blood type is important because it relates to the interests of various medical actions, even those relating to life safety.
At least, there are about four to six liters of blood in the human body. The blood is made up of red blood cells, white blood cells, and platelets. In addition, certain protein molecules called antigen and antibodies are also present in the human blood.
The antigen is a protein molecule that exists on the surface of red blood cells, while antibodies are proteins found in the blood plasma. Antigen consists of two types, namely Antigen A and Antigen B. The presence or absence of the two antigens can affect a person’s blood type, namely A, B, AB, or O.
Not only that, whether or not the Rhesus (Rh) factor in the blood can also determine the human blood type. The rhesus factor (RH) is an inheritance protein found on the surface of red blood cells. If the blood has an Rh protein, then the blood type includes an Rh positive. However, if none, mean Rh negative.
Why is blood type test necessary?
Blood transfusion
Blood type tests are required before blood transfusions or donating blood. This examination is also needed to ensure the patient receives the right type of blood during or after surgery.
Preventing transfusion complications
When the blood type of the donor and the Resistance does not match, blood clots and the destruction of harmful blood cells can occur.
Not all blood types can match each other, so it is important to receive a donor or donate blood according to your blood type. Receiving blood that does not fit your blood type can trigger blood clots and complications that are fatal to the body.
Symptoms of blood type mismatch in blood transfusion processes such as fever, chills, nausea, skin and eyes appear yellow, chest, stomach, or back pain, there is blood in the urine, and shortness of breath. The subsequent stages of complications due to mismatched transfusions can cause renal failure, or even death.
Important for pregnant women
This examination is also required for pregnant women. A mother who has a negative rhesus blood type and a husband with rhesus positive blood type is likely to give birth to a child with a rhesus positive blood group.
There is a risk of immune reactions when the mother’s blood cell destroys her baby’s blood cell because it is regarded as a foreign object. This condition is known as rhesus incompatibility. Therefore, a drug called Rhogam needs to be administered to prevent this condition from occurring.
How to do a blood type test
ABO system
ABO system blood grouping is conducted based on the presence or absence of antigen type A and type B on the surface of the erythrocytes, as well as antibodies (agglutinin) type α (anti-A) and type β (anti-B) in the plasma of the blood.
Rhesus system
Blood classification of Rhesus system based on the presence or absence of Agglutinogen (antigen) RhD on the surface of red blood cells. The RhD Antigen plays a role in the immune reaction.
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How To Find Out Your Blood Type
Blood Type Test Procedure
How to check blood type is first done by taking blood samples to be tested. Blood samples were taken from the vein or from the fingertips. In newborns, blood is taken from the umbilical cord or from the heel.
The vein blood sampling procedure is as follows: The officer will attach the hand band on the arm so that the veins are more visible. Before taking the sample, the skin will be cleaned using an antiseptic to prevent infection.
The syringe will be used to take blood samples. Once the blood is done, a puncture scar will be covered with gauze and bandages.
After the blood samples are drawn, the officer will determine the blood type of mixing blood samples with antibodies A and B. If the blood cells are clot when mixed with anti-A, it means that one has a blood type A.
Whereas if the blood clot when mixed with anti-B, then it means that one has blood type B.
Blood type O will not clot in both antibodies A and B because it has no antigen A and B. While the blood group AB will clot in both antibodies, because it has antigen A and B.
As for Rhesus examination, blood is mixed with anti-Rh serum or also called anti-D. If blood clots, it means that one has a blood with an Rh positive. Whereas if the blood does not clot, then it means that the blood has an Rh negative.