Transfusion Medicine - Krafts

Question 1

What determines a blood group?

Answer 1

Antigens on the red cell surface!

Question 2

Red Cell antigens

Answer 2

• Antigens are inherited from parents
• REALLY important for transfusion
• ABO and Rh systems

Question 3

ABO system

Answer 3

A, B, AB, or O

• A has A antigens
• Type O= neither A or B antigens

** what you don’t have, you make antibodies to.

Question 4

How do make an antigen?

Answer 4

1. Start with protein precursor
2. Add fucose to make H antigen
3. Add N-acetylgalactosamine to H Ag –> A Ag
4. Add galactose to H Ag –> B Ag

Question 5

H Gene

Answer 5

Everybody has this

Codes for an enzyme that makes H antigen

Question 6

A, B, and O genes:

Answer 6

• you have 2 genes
• 6 possible genotypes: AA, BB, AB, AO, BO, OO
• A and B code for enzymes that make A and B antigens
• O has no gene product

Question 7

Whats the big deal with blood types?

Answer 7

• We make antibodies to the antigens we DON’T have!!
• Anti-A antibodies lyse type A RBCs.
• Anti-B antibodies lyse type B RBCs

Question 8

Universal Recipient?

Answer 8

AB! Yay, no antibodies made – bring on any blood type for transfusion.

Question 9

Universal dOnor?

Answer 9

Type O

Type O can only get Type O blood.

Question 10

But WAIT, give type O to an A, the type O has anti A antibodies –Doesn’t that suck?

Answer 10

Nope, doesn’t matter :)

• -Not many antibodies in a packed unit of RBCs
• only concerned about the antibodies that the recipient has.

Question 11

Rh System:

What are the antigens?

Answer 11

D antigen! (=Rh factor)
Alleles: D and d

DD ==Rh+
Dd=Rh+
dd= Rh - (that’s me :] )

Question 12

Rh System: antibodies

Answer 12

These are acquired. You have to be exposed to the D antigen first.

Lack the D antigen +++ Get exposed to D + blood ==== make anti-D
-comes into play in pregnancy: give Rhogam if you have Rh- mom with Rh+ baby

Question 13

Other Systems:

Answer 13

• antibodies to antigens are acquired
• Only come into play if you have lots of transfusion or pregnancies.
• These aren’t included in routine tests

Question 14

Blood Transfusion: blood products

Answer 14

Whole blood, red cells, platelets, granulocytes, cryoprecipitates, fresh frozen plasma

Question 15

Apheresis donation

Answer 15

Take platelets or neutrophils and then return blood to the donor.

Question 16

Indications for WHOLE BLOOD transfusion

RBC, WBC, platelets, plasma

Answer 16

Massive Hemorrhage

Question 17

Indications for Red cell transfusion

RBC, and a little WBC, platelets, and plasma

Answer 17

Low hemoglobin

Question 18

Leukocyte-Reduced Red cell transfusion?

RBC, NO WBC, rare platelets, a little plasma

Answer 18

Decreased alloimmunization
Decreased allergic reaction
(patient is reacting to WBCs)

Question 19

Frozen Red Cell transfusion indications?

RBC, a few WBC

Answer 19

Storage of rare blood types

Question 20

Granulocyte transfusion indications?

neutrophils

Answer 20

Sepsis in neutropenic patients

-sometimes BMT patients or hard hitting chemo pts .

Question 21

Platelet transfusion indications?

Answer 21

Bleeding due to thrombocytopenia

Question 22

Fresh Frozen Plasma indications?

Plasma- including all coagulation factors

Answer 22

-Bleeding due to multiple factor deficiencies (DIC)

Question 23

Cryoprecipitates indications?

(fibrinogen, von Willebrand factor, VIII, XIII) –don’t need to know all that is in this

Answer 23

Low fibrinogen, vW disease, hemophilia A, XIII deficiency

Question 24

VIII indications?

Answer 24

Hemophilia A

Question 25

IX indications?

Answer 25

Hemophilia B

Question 26

Albumin indications?

Answer 26

Hypovolemia with hypoproteinemia

Question 27

IvIG indications? | intravenous

Answer 27

disease prophylaxis autoimmune disease Immune deficiency states

Question 28

Testing -- Forward Type:

Answer 28

Look to see what antigens are on red cells: 1. Take pt's red cells 2. + anti A antibodies 3 +anti human globulin (AHG) Clumping === A antibodies coating red cells and red cells HAVE A antigens No clumping == no A antigens *Do this with Anti B Antibodies too!

Question 29

Reverse Typing: *to double check your work

Answer 29

Looking for antibodies in serum 1. take pt's serum 2. + reagent red cells Type B 3. + AHG clumping == pt has anti B antibodies No clumping == pt does not have anti B antibodies --> they have Type B or AB blood.

Question 30

Crossmatch Test: do this when you know you are putting red cells into patient.

Answer 30

Patient serum + donor RBC + AHG ----> If you get clumping DON'T put donor blood in patient. *last double check

Question 31

Antibody Screen:

Answer 31

- look for antibodies against weird blood group systems. - do if pt has has had multiple pregnancies/transfusions and they are starting to have transfusion rxns. agglutination == + test (patient has antibodies against something in this sample)

Question 32

What goes wrong in transfusions?

Answer 32

Transfusion rxn: hemolytic (more serious) or non hemolytic Infections Circulatory overload Iron overload Graft-versus-host disease

Question 33

Acute Hemolytic Transfusion Reactions

Answer 33

-when pt has ABO antibodies against donor red cells Usually a clerical error :(

Question 34

Acute Hemolytic Transfusion Reactions: Symptoms: Labs:

Answer 34

Symptoms: fever, chest pain, hypotension -Hbg in serum & urine(pink) Labs: decreased haptoglobin increased bilirubin, DAT ++ Type and cross-match shows ABO mismatch

Question 35

Delayed Hemolytic Transfusion Reactions: -occurs days after transfusion

Answer 35

- caused by antibodies to non-ABO antigens - Hemolysis usually extravascular - presentation: falling Hgb after transfusion - usually NOT severe

Question 36

Febrile Transfusion Reactions: non hemolytic symptoms? Diagnosis? -rule out everything else Tx?

Answer 36

-Recipient antibodies against donor WBC Cytokines --> fever, headache, nausea, chest pain Tx? Tylenol. Leukocyte-reduced components

Question 37

Allergic Transfusion Reaction? - most common complication - non hemolytic

Answer 37

-Probs a host reaction to donor plasma proteins HIVES! Tx? hmmm -- Antihistamines

Question 38

Maybe my patient is having a transfusion reaction... what should I do?

Answer 38

STOP THE TRANSFUSION - check if right blood, right patient - monitor vitals - send blood, urine, and bag to blood bank - Lab will do DAT, ABO/Rh testing, look for hemoglobinuria

Question 39

Acute Hemolytic Transfusion rxn - What do we worry about?

Answer 39

Lysis of RBC and the release of the contents can cause kidney damage.

Question 40

Infection Danger of Transfusions? symptoms and tx?

Answer 40

- uncommon - Transfusion-related BACTERIAL infection (most common) - Sudden fever and shock - Test patient and blood unit! tx: aggressive resuscitation and antibiotic therapy

Question 41

What infections do we test blood for?

Answer 41

HIV (very uncommon) HTLV Hepatitis B and C (B is more common to get than C) Syphilis *Mankato double checks all these! Other possibilities: EBV, CMV, malaria, lyme's

Question 42

Circulatory Overload:

Answer 42

--too much blood is given too quickly symptoms: hypertension, congestive heart failure Tx: stop transfusion, give diuretics

Question 43

Iron Overload

Answer 43

Hey, too much iron can damage heart and liver, remember? Biggest risk: chronic anemia patients Tx: iron-chelating agents

Question 44

Graft vs. Host disease: Tell me about it... symptoms? Prevention?

Answer 44

Donor lymphocytes attack host (immunocomprimised pts or pts with blood relative donors (thanks mom)) Fever, rash, hepatitis, marrow failure usually FATAL -prevent by irradiating products