Transfusion Medicine Flashcards
(33 cards)
What determines blood type?
- The presence or absence of antigens on the RBC surface
Is the first transfusion ‘free’ for dogs?
No
- If a patient negative for DEA is given positive blood for the first transfusion, a delayed reaction will occur from the sensitization of the immune system gradually increasing the anti DEA 1 antibody titer
- Mismatches always result in delayed hemolytic reactions and prime recipients for severe acute reactions upon second exposure
Can Type A cats receive Type B blood?
- Technically yes but shouldn’t
- Their anti B antibodies are fairly weak in affinity and low in titer level so they cause a mild or delayed hemolytic reaction
- Transfused cells will only have a 1/2 life of 2 days
Can Type B cats receive Type A blood?
- No
- Type B cats have very strong anti A alloantibodies and will have an acute and severe hemolytic reaction
What blood can be given to a type AB cat?
- Both as they do not have any alloantibodies
- However, alloantibodies in plasma of type A & B blood may cause a reaction due to presence of anti A or anti BN antibodies
- Therefore type A is preferred as anti B antibodies occur at lower titer in type A blood - using pRBC minimizes amount of plasma containing anti B antibodies being transfused
What does the MAJOR crossmatch check?
- Mixes PATIENT PLASMA with DONOR RBCs
What does the MINOR crossmatch check?
- Mixes DONOR PLASMA with PATIENT RBCs
A patient should be cross matched if they received a transfusion _____ ago
> 4 days
What is a massive transfusion?
The replacement of blood approaching or exceeding one total BV within a 24 hour period
What does stored whole blood NOT contain?
- Viable platelets
- Labile clotting factors: F V, VIII, vWf
What does FFP contain?
- All labile (F V, VIII, vwf) and non labile clotting factors, plasma proteins, albumin, and globulins
What does FFP not contain?
Platelets
What does FP contain?
- non labile F II, VII, X, albumin, globulin
- Can be kept for 5 years
What is cryoprecipitate?
- The precipitate of thawed FFP
- Contains vWf, FVIII, fibrinogen, FXIII
- These factors are found in FFP, but administering cryo allows the same result but with less volume
- Hemophilia A
What is cryosupernatent?
-Supernatant that was produced during creation of cryo
- LACKS FVIII, FXIII, fibrinogen, vWf
- HAS albumin and remaining coag factors, including Vit K dependent factors
- Hemophilia B
How does albumin play a role in coagulation?
- Regulates coagulation by mediating thromboxane A2 levels
- HypoA leads to increased TXA2 levels, contributing to a hypercoagulable state
What are immunoglobulins used for?
- Used as an immunosuppresant in refractory immune mediated disease
What is platelet rich plasma? (PRP)
- Platelets harvested from a unit of FWB that is less than 8 hours old and has not been cooled
- Room temp platelets maintain viability better than refrigerated ones
- Shelf life of 5 days and requires constant agitation
Should plasma be type matched?
Yes, to prevent sensitization from RBCs they contain
Does plasma need to be given with a filter?
Yes
What are the four categories of reactions?
- Acute immunological
- Acute non immunological
- Delayed immunological
- Delayed non immunological
What is an immunological reaction?
- Caused by antigen-antibody interactions between donor & recipient
- Antibodies present in recipient plasma recognise RBC antigens as foreign
Is premedicating with antihistamines or steroids recommended?
- Only if there is a history of a reaction
- It will not prevent a reaction but may mask the early signs of one
What is a WBC/platelet incompatibility reaction?
Occurs when antibodies form against donor WBC or platelet antigens
