hematology

Question 1

OR blood loss includes:

Answer 1

• EBL
• blood in wound
• blood on drapes
• weighing sponges
• blood suctioned

Question 2

normal Hgb

Answer 2

males: 13-17 g/dL
females: 11.5-15.5 g/dL

Question 3

normal Hct

Answer 3

males: 40-55%
females: 36-48%

Question 4

normal platelet count

Answer 4

150,000 - 400,000 platelets/mL

Question 5

normal PT

Answer 5

11-13.5 seconds

Question 6

normal aPTT

Answer 6

30-40 seconds (activator speeds clotting time, narrows normal value range)

Question 7

normal PTT

Answer 7

60-70 sec

Question 8

normal INR

Answer 8

0.8-1.1
2-3 w/ warfarin

Question 9

whole blood: contents

Answer 9

Contains RBCs, plasma, platelets

Question 10

1 unit of whole blood is ___ mL

Answer 10

450 mL ± 50 mL

Question 11

packed RBCs: contents

Answer 11

only RBCs (2/3 plasma is removed)

Question 12

packed RBCs: unit, typical dose

Answer 12

• 1 unit: 250-300 mL ± 50 mL
• typical dose: 1-2 units

Question 13

packed RBCs: uses

Answer 13

• acute bleeding w/ hemodynamic instability
• symptomatic anemia (RBCs function for oxygen carrying capacity)

Question 14

packed RBCs: advantages and disadvantages

Answer 14

advantages: less volume expansion
disadvantages: lacks clotting factor

Question 15

leukocyte-reduced RBCs: contents

Answer 15

filtration removes 99.9% WBCs, platelets –> filtrate is wached w/ saline

Question 16

leukocyte-reduced RBCs: advantages

Answer 16

prevents febrile non-hemolytic transfusion rxns, less CMV transmission, less alloimmunization to class I antigens

Question 17

acute blood loss: Hgb levels

Answer 17

• Hgb >10 g/dL: transfusion rarely indicated
• Hgb 7-10 g/dL: transfusion indicated if pt is symptomatic (angina, tachy, dyspnea, etc)
• Hgb <7 g/dL: transfusion usually indicated

Question 18

allowable blood loss calculation

Answer 18

TBV x 0.3

Question 19

total blood volume calculation

Answer 19

weight in kg x 0.08 (normal is 1.2-1.5 gallons)

Question 20

FFP unit, dose measurements

Answer 20

• 1 unit: 250 mL
• dose: weight based, generally 10-15 mL/kg

Question 21

FFP uses

Answer 21

• massive transfusion
• coagulopathy pts
• emergency warfarin reversal

Question 22

plasma + solvent detergent: advantages

Answer 22

• inactivates lipid-coated virus, reduces prions and TRALI risk
• contains consistent coag factors

Question 23

anemia of chronic disease: requirements

Answer 23

• pts w/ chronic or autoimmune conditions that last longer than 3 months and cause inflammation
• impacts ability to utilize iron eeded to produce RBCs

Question 24

acute transfusion rxn: mild allergic

Answer 24

• HS rxn to foreign protein in donor product
• treat w/ antihistamines, stop transfusion

Question 25

acute transfusion rxn: anaphylaxis

Answer 25

- severe rxn; can be an IgA deficiency that makes alloantibodies against IgA

Question 26

acute transfusion rxn: febrile non-hemolytic

Answer 26

cytokines released from blood donor WBCs

Question 27

TACO

Answer 27

- non-hemolytic acute transfusion reaction - main cause of death - causes fluid overload, hypervolemia - will see alveolar infiltrates on CXR, systolic HTN, possible fever

Question 28

TRALI

Answer 28

- acute non-hemolytic transfusion rxn (transfusion related acute lung injury) - donor antibodies recognize recipient antigens - resolves in 48-96 hours - will see pulmonary edema, chills, fever, chest pain

Question 29

acute hemolytic rxn

Answer 29

- immune mediated: donor antigens are recognized as foreign by recipient antibodies - non-immune: RBCs are damaged prior to transfusion

Question 30

delayed hemolytic transfusion rxn

Answer 30

response to foreign antigen: recipient has been previously exposed (ie a prior transfusion, Rh in pregnancy) - recipient may be alloimmunized

Question 31

graft vs host disease

Answer 31

- delayed transfusion reaction - donor lymphocytes in immunocompromised pt's bone marrow recognize pt as foreign - occurs 5-10 days after transfusion (cytopenia, fever, rash, liver dysfunction)

Question 32

post-transfusion purpura

Answer 32

rare; thrombocytopenia-related bleeding disorders 5-10 days after transfusion