1. Compatibility Testing

2. Blood transfusions – who can receive blood from whom?
Blood Group
Antigens
Antibodies
Can give blood to
Can receive blood from AB
A and B
None
AB, A, B, O A B
A and AB
A and O
B and AB
B and O O

3. Blood can be received from:
Rh Blood Groups
Blood Type
Rh Antigen
Blood can be received from:
Rh +ve
Rh antigen present
Rh + ve AND Rh - ve
Rh –ve
Rh antigen absent
Rh -ve 3

4. O A B AB People with blood group O are called "universal donors"
People with blood group AB are called
"universal receivers." A B O AB
Universal Donor
Universal Recipient

5. Antibody clinical significance
If an individual is transfused with an incompatible blood group destruction of the RBC will occur.
This may result in the death of the recipient.

6. Transfusion Reactions
Transfusion reactions occur when mismatched blood is infused
Donor’s cells are attacked by the recipient’s plasma agglutinins.

7. What is compatibility testing?
Also called pre-transfusion testing
Purpose:
To select blood components that will not cause harm to the recipient and will have acceptable survival when transfused

8. Compatibility testing
Can be divided into 3 categories:
Pre-analytical procedures
Serological testing
Pos-tanalytical procedures

9. Pre-analytical phases
Patient identification
Specimen collection
Review of patient history

10. Patient Identification
Must confirm recipient’s ID from bracelet ON the patient
Full patient name and hospital number
Name of physician

11. Sample Identification
The sample should also have the full patient name, hospital number, and physician
Date and time of collection, phlebotomist’s name
All of this should be on the request form and the sample

12. Specimen Collection Collected in tube with EDTA.
If the venipuncture causes hemolysis, the sample is rejected.
Samples are labeled at the bedside .
Testing should be performed on samples less than 72 hours

13. Getting the history
Look at recipient’s records for any prior unexpected antibodies
Previous transfusion reactions

14. Serological Testing Three tests: ABO/Rh
Antibody detection/identification
Crossmatch

15. Test for transfusion
Antibody Screen is a test that is always performed on patients who may require red blood cell transfusion, and this test will detect most clinically significant red cell antibodies.

16. Crossmatching Purpose: Prevent transfusion reactions
Increase in vivo survival of red cells
Double checks for ABO errors
Another method of detecting antibodies

17. Crossmatch No agglutination (compatible) Agglutination (incompatible)
Donor RBCs (washed)
Patient serum

18. Routine Crossmatching
This consists of testing the patient’s serum or plasma against donor red cells by:
1-Direct agglutination test, called immediate Spin technique, in which we just mixture of recipient serum and donor cells for 5 minutes at room temperature, followed by centrifugation at 200 g for 30 seconds and then checking for agglutination.

19. Routine Crossmatching
2- Indirect agglutination test (IAT), the IAT tubes are left for minutes incubating at 37 oC , they are then taken out washed four times in normal saline and then two drops of Antihuman globulin (AHG) is added and mixed, followed by centrifugation for 30 seconds art 200 g, and then checking for agglutination.

20. The procedure
Donor cells are taken from segments that are attached to the unit itself
Segments are a sampling of the blood and eliminate having to open the actual unit

21. Post-analytical phase
Labeling form includes patient’s full name, ID number, ABO/Rh of patient and unit, donor #, compatibility results.
The unit is visually inspected for abnormalities, such as bacterial contamination, clots, etc

22. Wha can be given in an emergency?
Group O Rh-negative red cells or AB plasma
Emergency release
Women below or of childbearing age
Or if in doubt