Blood products and transfusion

Question 1

What are the two main components of blood?

Answer 1

Cellular elements (RBCs, WBCs, platelets) and plasma.

Question 2

What happens when blood is centrifuged?

Answer 2

Plasma rises to the top, solutes settle to the bottom, platelets in the middle.

Question 3

What is the effect of high cholesterol on centrifuged blood?

Answer 3

Fat gel layer may form on top.

Question 4

What are the blood types and Rh factor percentages?

Answer 4

Types: A, B, AB, O; Rh+ ~85%, Rh- ~15%.

Question 5

Why is Rh status important in transfusion?

Answer 5

Rh incompatibility can lead to fetal issues in pregnancy and immune responses.

Question 6

What is the universal donor and recipient?

Answer 6

Universal donor: O negative; Universal recipient: AB positive.

Question 7

Why are females of childbearing age typically given O negative blood?

Answer 7

To prevent Rh sensitization and future fetal hemolytic disease.

Question 8

What is the purpose of a type and screen?

Answer 8

Identifies ABO/Rh and screens for antibodies/antigens.

Question 9

Why can type and screen take time?

Answer 9

Screening for hundreds of possible antibodies can delay processing.

Question 10

Why is type and screen important for high-risk surgeries?

Answer 10

Prepares for potential transfusion and avoids emergency uncrossmatched transfusions.

Question 11

What transfusion fluid was used in WWI/Vietnam?

Answer 11

Whole blood.

Question 12

What replaced whole blood in the 1970s-1990s?

Answer 12

Component therapy (RBCs, FFP, etc.).

Question 13

Why was normal saline originally used?

Answer 13

Rehydration for cholera, not designed for resuscitation.

Question 14

What are the problems with crystalloid resuscitation?

Answer 14

Dilutes blood, causes inflammatory response, and disrupts microclots.

Question 15

What are the four main blood components?

Answer 15

PRBCs, FFP, Cryoprecipitate, Platelets.

Question 16

What is LTOWB?

Answer 16

Low Titer O Whole Blood – screened for minimal antibodies.

Question 17

What does CPDA-1 do in blood storage?

Answer 17

Citrate chelates calcium, phosphate buffers, dextrose is fuel, adenine extends ATP production.

Question 18

What happens to 2,3-DPG in stored blood?

Answer 18

Decreases over time, shifting O2 curve left and impairing oxygen delivery.

Question 19

How are PRBCs prepared?

Answer 19

By removing 200-250mL plasma from whole blood.

Question 20

What is the volume of PRBCs?

Answer 20

Typically 200-350mL.

Question 21

What is the effect of PRBC transfusion?

Answer 21

Increases Hb by ~1g/dL and Hct by 3%.

Question 22

Do PRBCs contain platelets or granulocytes?

Answer 22

No.

Question 23

How is FFP prepared?

Answer 23

Plasma removed from WB within 8 hours, frozen at -18°C.

Question 24

What is in FFP?

Answer 24

Water, carbs, fats, minerals, clotting proteins (stable and labile).

Question 25

How much FFP is needed to raise clotting levels?

Answer 25

10–15 mL/kg raises factors by ~2-3%.

Question 26

What is cryoprecipitate?

Answer 26

Protein-rich fraction from thawed FFP containing Factor VIII, vWF, fibrinogen, Factor XIII.

Question 27

When is cryo used?

Answer 27

Massive transfusion, congenital bleeding disorders, fibrinogen replacement.

Question 28

How are platelets prepared?

Answer 28

From PRP or apheresis, then re-centrifuged.

Question 29

What is the volume of apheresis platelets?

Answer 29

250-300mL.

Question 30

How much does one unit of platelets increase PLT count?

Answer 30

5,000-10,000.

Question 31

How do pooled platelet units affect PLT count?

Answer 31

6-pack or 10-pack increases PLT by 60,000–100,000.

Question 32

Why should platelets not be warmed?

Answer 32

Causes aggregation; academic importance.

Question 33

What fluids are safe with blood transfusion?

Answer 33

Normal saline, Normosol, or PlasmaLyte.

Question 34

Why avoid Lactated Ringers with blood?

Answer 34

Contains calcium which can cause clotting.

Question 35

Why must blood be warmed?

Answer 35

To prevent hypothermia and coagulation impairment.

Question 36

What devices are used to warm blood?

Answer 36

Belmont, Level 1, Ranger, others.

Question 37

Why is whole blood advantageous?

Answer 37

Fewer additives, superior coagulation, easier logistics.

Question 38

How does whole blood compare to component therapy?

Answer 38

Less diluted, better platelet & factor levels, single product.

Question 39

What causes hypocalcemia during transfusion?

Answer 39

Citrate binds ionized calcium (iCa).

Question 40

What are signs of transfusion-induced hypocalcemia?

Answer 40

QT prolongation, seizures, ↓ cardiac output.

Question 41

When should calcium be replaced?

Answer 41

Every 4 units of blood; monitor iCa.

Question 42

Which calcium replacements are used?

Answer 42

Calcium chloride or gluconate.

Question 43

What are signs of hemolytic transfusion reactions?

Answer 43

Fever, chills, hypotension, dyspnea, hemoglobinuria.

Question 44

What mediates acute hemolytic reactions?

Answer 44

IgM antibodies and complement.

Question 45

What are symptoms of allergic transfusion reactions?

Answer 45

Itching, urticaria, erythema, anaphylaxis.

Question 46

What is TRALI?

Answer 46

Acute lung injury within 6 hours of transfusion, non-cardiogenic.

Question 47

What are TRALI signs?

Answer 47

Hypoxemia, bilateral infiltrates, no JVD, minimal diuretic response.

Question 48

What is TACO?

Answer 48

Volume overload causing pulmonary edema.

Question 49

How do TACO and TRALI differ?

Answer 49

TACO has HTN, JVD, responds to diuretics; TRALI does not.

Question 50

What causes delayed hemolytic reactions?

Answer 50

IgG antibodies.

Question 51

What is transfusion-associated GVHD?

Answer 51

Viable donor lymphocytes attack host; causes pancytopenia.

Question 52

How is GVHD prevented?

Answer 52

Irradiated cellular products.

Question 53

What is post-transfusion purpura?

Answer 53

Antibodies against platelets cause thrombocytopenia.

Question 54

What are signs of bacterial contamination in blood?

Answer 54

Fever, shock, hemoglobinuria.

Question 55

What causes it?

Answer 55

Gram-negative endotoxins; improper handling.

Question 56

What is transfusion-induced hemosiderosis?

Answer 56

Iron overload from repeated transfusions.

Question 57

How is hemosiderosis managed?

Answer 57

Chelation therapy or reduced transfusion frequency.

Question 58

What qualifies as an adult massive transfusion?

Answer 58

Replace total blood volume in 24h, 50% in 3h, or 4 units in 4h.

Question 59

What is the standard MTP ratio?

Answer 59

1:1:1 PRBCs : FFP : Platelets.

Question 60

Why is whole blood better in MTPs?

Answer 60

Higher hemostatic potential, fewer additives.

Question 61

What are key TEG parameters?

Answer 61

R-time, K-time, MA, Ly30.

Question 62

What does a prolonged R-time indicate?

Answer 62

Coagulation factor deficiency; give FFP.

Question 63

What does low MA mean?

Answer 63

Platelet dysfunction; give platelets.

Question 64

What does rapid clot lysis (Ly30) suggest?

Answer 64

Hyperfibrinolysis; give cryoprecipitate.

Question 65

What are initial steps after suspected transfusion reaction?

Answer 65

Stop transfusion, keep IV open, notify blood bank, send blood/urine samples.

Question 66

Why should you be cautious declaring a transfusion reaction?

Answer 66

It may delay further transfusions crucial for patient survival.