CCP 107 - Transfusion Medicine

Question 1

What is plasma and what percentage of blood volume is it?

Answer 1

55% of blood volume.
Water and proteins. Proteins are: albumin, globulins (alpha, beta, immunoglobulins)

Question 2

What percentage of blood is cells and what are the different types of cells?

Answer 2

45%.
Erythrocytes.
Leukocytes .
Thrombocytes

Question 3

Name the types of leukocytes

Answer 3

Granulocytes (Neutrophils, Eosinophils and Basophils) and Agranulocytes (Lymphocytes (B lymphocytes, T lymphocytes and Natural killer cells) and Monocytes)

Question 4

What is the universal plasma donor?

Answer 4

Type AB because it has no antibodies in the plasma.

Question 5

What is the universal red blood cell donor?

Answer 5

Type O because it has no antigens on the cells.

Question 6

What type of blood is used as a universal plasma donor as well as Type AB?

Answer 6

Type A

Question 7

What is the reaction that occurs in blood when antigens and antibodies interact?

Answer 7

Agglutination

Question 8

How does blood type compatibility relate to transfusion of platelets?

Answer 8

Platelets can be donated from any type to any type because they don’t have antigens or antibodies.

Question 9

Explain Rh hemolytic disease

Answer 9

Rh positive father and a Rh negative mother make a baby who is Rh positive. Rh positive baby’s blood cells enter mother’s bloodstream during childbirth. Mother produces Rh antibodies which remain in bloodstream and attack future Rh+ baby’s blood causing hemolysis.

Question 10

How much does 1 unit PRBCs increase serum Hgb by?

Answer 10

10 g/L

Question 11

What is the lower threshold Hgb level for transfusing PRBC’s in a symptomatic patient?

Answer 11

70 g/L

Question 12

Why do we base transfusion requirements on clinical exam, not Hgb levels in actively bleeding patients?

Answer 12

The Hgb level will lag behind as the remaining Hgb has to redistribute through the body to give an accurate reading.

Question 13

What is the shelf life of PRBCs?

Answer 13

21-42 days

Question 14

What is the volume/unit of PRBCs?

Answer 14

250-350 mL

Question 15

Define hematocrit

Answer 15

the concentration of RBC’s in a unit. High hematocrit = viscous blood with lots of cells. If you bolused saline and diluted the blood = low hematocrit.

Question 16

What is the initial dose of PRBCs?

Answer 16

2 units. (increases the Hgb by 20 g/L)

Question 17

What are the two ways to collect platelets?

Answer 17

Apheresis - 1 donor, blood removed, platelets removed, remaining blood components replaced
Pooled - platelets collected from 4-5 donors pooled together to create a unit. Pooled is a higher risk of infection and increased risk of presence of antibodies.

Question 18

How much will 1 platelet unit increase the platelet level by?

Answer 18

15-25 x10^9/L (this is just the unit, 50 is the answer)

Question 19

What is a normal platelet count?

Answer 19

300-450 x10^9/L

Question 20

Define thrombocytopenia

Answer 20

Low platelet count
<50 x10^9/L

Question 21

What is the shelf life of platelets?

Answer 21

5 days. After that, risk of bacterial infection.

Question 22

What is the dose of platelets?

Answer 22

5 mL/kg

Question 23

When should platelets be transfused?

Answer 23

To facilitate primary hemostasis in patients with platelet deficiency or dysfunction
To prevent or control bleeding
or to raise the platelet count.

Question 24

Who should receive irradiated platelets and why?

Answer 24

Immunocompromised or immunoincompetent patients. Irradiation prevents transfusion-associated graft vs host disease.

Question 25

What is the adult dose of plasma for transfusion?

Answer 25

15 ml/kg (3-5 units)

Question 26

What are the indications to transfuse plasma? (5)

Answer 26

1. Moderate to severe bleeding 2. To prevent periprocedural bleeding if patient with acquired factor deficiency 3. Warfarin reversal ONLY if PCC unavailable. 4. Factor replacement if factor concentrate unavailable. 5. Plasmapheresis for thrombotic thrombocytopenic purpura.

Question 27

List 4 situations where plasma is not indicated

Answer 27

1.j

Question 28

What is an erythrocyte (origin, role)

Answer 28

Bone marrow, carries o2/co2

Question 29

Role of a neutrophil

Answer 29

Phagocytosis of bacteria and fungus

Question 30

Role of eosinophil

Answer 30

Fights parasites, allergic reaction

Question 31

Role of basophil

Answer 31

Releases histamine and other inflammatory mediators

Question 32

Role of lymphocytes

Answer 32

(b, t, nk) produce antibodies, cell mediated immunity

Question 33

Role of monocytes

Answer 33

Macrophage or dendritic

Question 34

What is human leukocyte antigen (HLA) and relevance in setting of blood product admin

Answer 34

Present on the surfaces of cell membranes of circulating platelets, WBCs (buffy coat <1%) and most tissues. Pts receiving from pool of donors may experience febrile transfusion reaction and the ensuing antigen-antibody reaction destroys the platelets. *hla-matched platelet transfusions are best

Question 35

Describe PRBCs

Answer 35

Retain all the characteristics of whole blood minus 250mL of platelet rich plasma. Indicated for actively bleeding pts and estimated blood loss (~30%/1500mL loss will produce symptoms). For hospitalized pts, Hgb <70g/L or <80g/L undergoing sx or preexisting cardiovascular disease.

Question 36

Describe platelets

Answer 36

Manufactured in bone marrow, necessary for normal clotting response. Indicated for thrombocytopenia (<150x 10^9 and/dysfunctional) AND clinical exam

Question 37

Describe FFP

Answer 37

Clotting factors- alpha and beta globulin and fibrinogen/factor I; albumin, immunoglobulin (antibodies). Indicated in blood loss, coagulation deficiencies, warfarin reversal (if PCC isn’t available) and TTP (thrombotic thrombocytopenia). Must be used in 5 days once thawed. Type AB is universal plasma donor but type A is carried by BCEHS (should be ABO compatible, Rh not required)

Question 38

Describe Cryoprecipitate

Answer 38

Aka antihemophilic. Frozen blood product made from plasma. Contains vWF, fibrinogen, factor Viii and Xiii. May be used in bleeding pts with fibrinogen <1g/L due to severe hepatic failure, uremia, or DIC. Not ABO compatibility required, but preferred. Rh not required

Question 39

Describe prothrombin complex concentrate (pcc)

Answer 39

Aka octaplex. Contains factors ii, VII, IX, x and antithrombotic proteins c and s. Indicated for urgent reversal of bleeding from Vit K antagonist (warfarin/Coumadin). VitK (long onset ~6hrs) still given to prevent rebound effect and lots of factors in liver ready to go but need VitK as last conversion step.

Question 40

Describe Albumin

Answer 40

Prepared by the fractionation of pooled plasma. Used for volume replacement in burns, trauma, surgery, or infections. ABO and Rh comparability not required. 25% solution will produce 5x volume from extravascular

Question 41

Describe plasma protein fractions

Answer 41

83% albumin, 17% globulins. Indicated for volume expansion in hypovolemia (shock or burns) or hypoproteinemia

Question 42

Describe anaphylaxis as it pertains to blood transfusion

Answer 42

Usual s/s— chills, facial and laryngeal edema, pruritus c’est urticaria, bronchospasm, fever, nause, vomit. If isolated urticaria or hives, continue transfusion and treat with antihistamine. If the pt has known history of this type of allergic reaction, premeditate before transfusion

Question 43

Describe hemolytic transfusion reactions

Answer 43

Caused by ABO or Rh incompatibility, infrasonic incompatability, improper cross matching, or improper blood storage. May occur during transfusion (1-2hrs) or within 3-7days. Immediate: severe from RBCs quickly destroyed and rbc remnants into bloodstream- hemoglobinuria, abnormal bleeding from open sites, hypotension, CP, facial flush, sob, fever/chills, flank pain. Delayed: most often in occur in pts who are sensitized by previous transfusions/preg/transplant. Usually mild s/s (fever/chills, jaundice)

Question 44

Describe TRALI

Answer 44

transfusion related acute lung injury. Acute onset (0-6hrs) hypoxemia, clear evidence of bilateral pulmonary edema on imaging. S/s dyspnea, hypoxemia, fever, and hypotension. Usually resolves in 24-72hrs

Question 45

Describe TACO

Answer 45

transfusion-associated circulatory overload. Circulatory overload from impaired cardiac function and/or excessively rapid rate of transfusion. Evidence of acute pulmonary edema on physical exam and/or imaging. S/s sob, orthopnea, tachycardia, increased venous pressure, HTN. Possibly fever. Onset 0-12hrs, most common cause of death from transfusion. Risk factors- >70YO, HF, LV dysfunction, MI, renal dysfunction, positive fluid balance.

Question 46

Describe DIC

Answer 46

Disseminated intravascular coagulation. Complex coagulopathy that can develop in critically ill patients and causes bleeding and thrombosis.

Question 47

Discuss infection as a transfusion complication

Answer 47

Bacterial- contamination from skin commensals from donor (venipuncture skin plug), unrecognized bacteremia from donor, contamination from handling or environment. S/s- rigors, fever, tachy, hypotn, n/v, sob, DIC. Delayed presentation <24hrs Virus- risk is donating in the “window period” (between infection and detectable appearance). Exps (in order of likelihood)- west Nile, hepB, HIV, hepC.

Question 48

Can you give blood to a life threatening hemorrhage without their consent?

Answer 48

Yes- if they are unable to provide consent. Health Care (Consent) and Care Facility (Admission) Act- Section 12

Question 49

What is an example of a synthetic blood substitute

Answer 49

TXA- synthetic antifibrinolytic