Simple test tube method:
- Remove a segment or several segments from the donor unit. Squeeze the blood from the segment and centrifuge at the lowest speed for 10 minutes.
- Aspirate 0.2mls of the packed red blood cells and add it to 4.8 mls of 0.9% normal saline.
- Put 0.1 mls of this mixture into 3 small glass tubes.
- Next put 0.1mls of the patient’s serum or plasma into each of the 3 tubes. Now each tube contains 0.1ml of the donor red cells and 0.1 mls of the patient’s serum or plasma.
- Incubate 1 tube at room temperature, 1 tube at refrigerator temperature and 1 tube at 37°C.
- Centrifuge for 1 minute.
- Examine the supernatant for any hemolysis.
- Examine the cell button. Flick the test tubes. The fluid in the tubes should redden as the cells disperse.
- If the red cell button is agglutinated examine a drop under low microscopic power.
- For minor cross match use the patient’s red cells and the donor’s serum or plasma.
For the controls use the patient’s red cells and the patient’s plasma.