Compatibility testing Flashcards
major crossmatch
patient serum + donor cells
minor crossmatc
donor serum + patient cells
not done after 1970s
crossmatch today
serves as a double check of ABO errors & clinically significant Ab
compatibility testing vs crossmatch
compatibility includes crossmatch! also includes: accurate recipient ID sample collection & handling required pre-transfusion testing process begins w/ the transfusion requires & ends w/ the transfusion of blood product to patient
crossmatch testing
mix donor cells & recipient plasma IS & read add potentiator 37 incubate & read wash 3x add AHG & read
crossmatch testing interpretation
compatible or incompatible (doctor needs to override in order to use incompatible blood)
Regulatory organizations
AABB: american association of blood banks
FDA
3 types of crossmatch
immediate spin crossmatch- IS
computer crossmatch
Antiglobulin XM
usage of IS crossmatch
when there is no evidence of Ab in current sample or past history
usage of AHG XM
when patient has current or past clinically significant antibody
will be positive if unit had positive DAT
usage of computer XM
only when recipient dose not have clinically significant Ab in current or past samples
XM limitations
viral transmission, allergic or febrile reactions
cannot detect all antigens, especially low frequency ones
Kidd antibody could be extremely low titer
1 unit of packed RBCs should increase Hct/Hgb by :
3% Hct or 1g/dL Hgb
Pretransfusion testing: specimen collection
samples for pretransfusion testing can be used for 3 days (day of collection is day 0)
no serum separators
must be retained by blood bank ~7-10 days
special specimen collection procedure for 30 day specimen
pertains only to ppl undergoin a surgery within 30 days & have not had a transfusion/pregnant in the last 3 months
