1. Take five small (e.g. 63 9.5 mm) tubes* and label them 1 to 5.
When reusing tubes for blood transfusion work, use glass tubes because it is difficult to completely clean plastic tubes of traces of protein or detergent.
2. Pipette into each tube as follows:
Tube 1 : 1 volume anti-A serum
1 volume 3–5% patient’s
red cells
Tube 2 : 1 volume anti-B serum
1 volume 3–5% patient’s
red cells
Tube 3:. 1 volume patient’s serum
1 volume 3–5% A cells
Tube 4: 1 volume patient’s serum
1 volume 3–5% B cells
Tube 5: 1 volume patient’s serum
(Auto- 1 volume patient’s 3–5%
control) red cells
3. Mix the contents of the tubes by gently tapping the base of each tube with the finger.
4. Leave the tubes at room temperature for 5 minutes. Centrifuge at lowest setting (e.g. 150 g) for 1 minute or at 500–1 000 g for 10–15 seconds.
5. Replace the tubes in the rack in the same
position as before centrifuging. Read the results by tapping gently the base of each tube, looking for agglutination or haemolysis. Record the results in the Blood Grouping Book and on the patient’s form. Interpret the results as follows:
Tube1 Tube2 Tube3 Tube4 Tube5 B/G
Anti-A Anti-B A cells B cells Ctrl.
+ – – + – A – + + – – B + + – – – AB – – + + – O
Haemolysis is recorded as a positive (+) reaction. When a reaction is weak, record this (WK).
Group O donor blood found to contain anti-A and anti-B haemolysins should be labelled. Use as whole blood for group O patients only or use as concentrated red cells
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