Blog Post

Blood Grouping Techniques

29 April 2015

Blood Grouping Techniques

Blood grouping accuracy is vital in the treatment of many bleeding disorders, in surgery or because of major blood loss, but there are actually a few techniques used to provide blood grouping in different circumstances. Here we take a look at some of the most common blood grouping techniques.

Simple blood grouping

In simple testing, a blood grouping reagent (containing specific antibodies) is mixed with a sample of the patient’s red blood cells. The reaction that occurs then illustrates what blood type the patient is. Whichever antibodies makes the red blood cells agglutinate (clump together) is the blood group of the patient. For instance, if the red cells (or erythrocytes as they are known) agglutinate when mixed with a reagent containing Anti-A antibodies, then the patient’s red blood cells contain A antigens (and the patient is said to be group A positive). Each blood grouping reagent is able to detect a specific blood group. In Europe, a blood donor’s blood is typed for at least 8 different blood groups, requiring 8 different blood grouping reagents, before the blood donation is released for transfusion into a patient.

The importance of cross matching in blood transfusions

If a patient needs a blood transfusion then it is imperative that the blood given via transfusion is compatible with the patient’s own blood. This is because if incompatible blood is transfused into the patient, the patient’s immune system will attack the incompatible blood which may be fatal for the patient. 

In order to avoid this, a technique known as cross matching is performed. This involves mixing a sample of the donor’s red blood cells with a sample of the patient’s blood plasma. This mixture is incubated at 37oC and after the required time, the mixture is examined carefully for clumping of the red blood cells. If no clumping is observed, the donor’s blood can safely be transfused into the patient.

Equipment needed

It is of course vital that those undertaking blood grouping work use high quality sera to ensure an accurate result.

Here at Lorne Labs we offer high quality grouping reagents for Rhesus, ABO, MN&S and Kell, including a range of rare grouping sera. Lorne’s blood grouping reagents are compliant will all UK and European guidelines.

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