Transfusion Medicine Flashcards
Understand the how a patients blood group is determined in the transfusion laboratory
- Forward Group: Which antigen is on the red cells? A,B, or both?! Put your Red cells with Anti A and anti B. Clumping means you have that A or B!
- Reverse Group: Which antibody is in the plasma? Anti-A, anti-B, or both? Your red cells with A, and B antigen!! So if it clumps you have antibodies against A or B!
- Rh… Is there Rh(D) antigen on the red cells? Yes = Rh positive. Your blood cells with Anti D.
Discuss the significance of the antibody screen
- To test for unexpected non-ABO red cell antibodies in the plasma? Rh, Kell, Kidd, Duffy… etc!! These antibodies develop from transfusion and pregnancy! check your blood with others to see which antigens our patient has!!!
- If clumping in any reaction wells… means antibody screen is POSITIVE. There is at least one non-ABO anibody present!
Understand what is involved in performing a cross match on a blood sample
- After the Type and Screen is complete… if antibody screen negative.. electronic match… computer verifies the retrieved units are compatible for the patient. If screen positive, additional delay in getting blood.. there is an unknown non-ABO antigen in blood which we don’t know… Group O blood has no antigen… so it is compatible with EVERYBODIES plasma!!
What blood do we use for most emergency’s in critical or life threatening circumstances?
O+!!!! Not O negative because it is so rare!
What to do down the line if patient has positive antibody screen?
- If you get a positive antibody screen… then the patient comes back 10 years later for blood transfusion…. Might have sleeping MEMORY cells.. Which would make current screen negative… so if you ever have a POSITIVE antibody screen… we will follow that FOREVER! So that we don’t trigger a delayed reaction!!!
xplain the importance of proper patient identification on a patient blood sample
- Because if you don’t…could mix up blood.. cause HUGE PROBLEMS AND EVEN DEATH.
- Mislabeled specimen… is always rejected… leads to wrong blood in wrong patient = bad. haha.
What to do If transfusion Reaction is suspected:
- Stop the transfusion!
- Keep intravenous line running with normal saline!
- Always obtain full set of vital signs = temp, heart rate, blood pressure, respiratory rate, and O2 saturation.
- Clerical check… verify info on product tag against patients ID band.
Discuss the differential diagnosis of a fever temporally associated with transfusion
- 50/50 for if it is related to the transfusion!If it IS related to transfusion could be…
- Febrile Non hemolytic transfusion reaction
- Bacterial contamination or sepsis
- Acute hemolytic transfusion reaction
- Transfusion related acute lung injury
- Document all signs and symptoms!! We are eyes and ears… Can also do other tests.. such as blood cultures,
- Never restart the originial transfusion
List the components of a transfusion reaction investigation
- Clerical Check
- Visible Hemolysis? red plasma after centrifugation? (yellow is normal)
- Direct antiglobulin test (DAT)… treat patients red cells invivo with antibody.. then help process along by treating with IgG… it then helps them hold hands and can form clumping
- Document all symptoms
- May also: Re-screen for antibodies.
Provide a differential diagnosis for jaundice following a transfusion
- Is it nothing to do with transfusion or something to do with the transfusion? Acute or delayed hemolytic transfusion reaction?
What is RhIG?
It is ANTI D! RhIG(Rh Immunoglobin) discovered in Canada… it is a Canadian product. It is ANTI D. So if giving units which are D positive and if you give RhIG it will connect to Rh and then be collected by spleen and be filtered out. Mainly used in pregnancy… women Rh negative, chord is tested as Rh positive… given Anti D right away! In delivery… usually only get 5mL of blood cross… whereas transfusion is 250mL… usually give immediately.. Although still good after 28 days… RhIG given to stop formation of Anti-D.
When would you do a transfusion?
If they have anemia!!! Never transfuse if Hb level is over 70!!!! Symptoms of anemia are HIGH HEART RATE, sweatiness, fatigue, palor, shortness of breath. We transfuse to increase oxygen carrying capacity.
Why do we care so much about Rh antibodies and not the numerous others?!
Rh antibodies are not endogenously occuring! Theres lots of antibodies on bloodcells… so why do we worry so much about Rh?!!!!!! Reason is because 85% chance of forming antibody if you transfuse them!!! Ex… for Kell antibody… only 5% of people will form antibodies… Kell is the next highest rate… that’s why we focus so much on Rh!!!!
