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Flashcards in 36 Transfusion medicine Deck (36)
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1
Q

What is a unit of RBC?

How is it prepared? (4)

A

Concentrated red blood cells.

Plasma removed and replaced with glucose, electrolytes and adenine.

2
Q

How is a unit of RBC stored?

A

4 degrees for up to 35 days.

3
Q

How is a unit of RBC administered?

A

Over 1.5-3 hours.

4 hour time limit from cold removal and end of transfusion.

4
Q

What is the transfusion threshold?

A

Lowest threshold of haemoglobin not associated with symptoms of anaemia.

5
Q

How does the body adapt to anaemia? (6).

A
Increased cardiac output.
Increased coronary artery flow.
Increased oxygen extraction.
Increased 2,3-DPG levels.
Increased EPO production.
Increased erythropoiesis.
6
Q

What does tissue oxygenation depend on?

A

Concentration of haemoglobin.

7
Q

What is the trigger for blood transfusions in anaemia?

A

Less than 70g/L with mild symptoms.

Less than 80g/L with CV disease.

8
Q

When should blood transfusion take place in anaemia from acute blood loss?

A

More than 30% of blood volume or more than 1500mL lost.

9
Q

What is the aim of blood transfusion in chronic ischaemia due to myeloid failure? (3)

A

Symptomatic relief.
Improvement in quality of life.
Prevention of ischaemic organ damage.

10
Q

What is the aim of blood transfusion in chronic ischaemia due to inherited anaemia?

A

Suppression of endogenous erythropoiesis.

Target: 100-120 g/L.

11
Q

How are platelets stored and used?

A

Room temperature for 5 days from collection.

Transfusion over 30 minutes.

12
Q

When should platelets be transfused?

A

Treat bleed due to severe thrombocytopenia or platelet dysfunction.
Prevention of bleeding.

13
Q

What are the contra-indications for platelet transfusion?

A

Heparin indued thrombocytopenia and thrombosis.

Thrombotic thrombocytopenia purpura.

14
Q

How is fresh frozen plasma stored and administered?

A

-30 degrees for up to 24 months.

Thawed before used, transfused over 30 minutes.

15
Q

When should fresh frozen plasma be transfused? (3)

A

Coagulopathy with bleed/surgery.
Thrombotic thrombocytopenia purpura.
Massive haemorrhage.

16
Q

What is the treatment for life-threatening bleeding in Warfarin overdose?

A

Prothrombin complex concentrate.

Plasma-derived Vit K dependent factors: II VII IX X.

17
Q

When should CMV negative blood products be used?

A

Children under 1
Intrauterine tranfusion
Congenital immunodeficiency
Pregnant women (unless known +ve)

18
Q

When should irradiated blood products be used? (5)

A
Intrauterine transfusions.
Congenital immunodeficiency.
Hodgkin Lymphoma.
Stem cell / marrow transplant patients.
After purine analogue chemo.
19
Q

What is the pathogenesis of acute haemolytic reaction-ABO incompatibility? (4)

A

Deposition of Hb in renal tubules causes renal failure.
Stimulation of cytokine storm.
Microvascular thrombosis.
Generalised vasoconstriction mediated by NO.

20
Q

What is group and screen?

A

ABO and Rh group identification.

Screening for other major blood group antigens.

21
Q

What is cross-matching?

A

Donor selected with correct ABO, Rh and antibodies.

Some of donor and patient blood mixed to see if reaction occurs.

22
Q

What are the immunological acute transfusion reactions? (3).

A

ABO incompatibility.
Allergic reaction.
TRALI (transfusion related acute lung injury).

23
Q

What are the non-immunological acute transfusion reactions? (3).

A

TACO (transfusion associated circulatory overload).
Bacterial contamination.
Febrile non-haemolytic transfusion reaction.

24
Q

What are the delayed transfusion reactions?.
2 immunological.
1 non immunological.

A

Transfusion associated graft vs host disease. Post transfusion purpura.
Transfusion transmitted infection (viral/prion).

25
Q

Which risk is great: transfusion transmitted infection or the wrong blood product being given?

A

Wrong blood product.

26
Q

What are the symptoms of acute haemolytic reaction ABO incompatibility? (7)

A
More severe within 15mins.
Fever
Back, chest, and infusion pain 
Hypotension /shock
Hemoglobinuria
Increased bleeding (DIC)
Sense of “impending death”
27
Q

What is the pathogenesis of delayed haemolytic reaction?

A

Antigens form after transfusion toe RBC antibodies that aren’t ABO.

28
Q

When does a delayed haemolytic reaction present?
Symptoms? (3)
Bloods? (3)

A

3-14 days post transfusion.
Fatigue, jaundice, ± fever.
Drop in Hb. Increased LDH and indirect bilirubin.

29
Q

What is Coomb’s test?

A

Anti-human globulin test.

Test for incomplete IgG antibodies.

30
Q

What is transfusion related lung injury?

How does it occur?

A

Acute lung injury within 6hrs of transfusion.

Donor antibodies to recipient leukocytes - activated WBC lodge in capillaries + damage them.

31
Q

What is acute lung injury?

A

Hyperaemia.
New bilateral CXR infiltrates.
No evidence of volume overload.

32
Q

How is TRALI treated?

A

Supportive: O2, or mechanical ventilation.

33
Q

What the presentation of transfusion related circulatory overload (TACO)? (7)

A
Sudden dyspnoea
Orthopnea
Tachycardia
Hypertension
Hyperaemia.
Raised JVP and BP.
34
Q

What are the risk factors for TACO? (3)

A

Elderly or young.
Compromised left ventricular function.
Increased volume or rate of transfusion.

35
Q

What are the two types of allergic reaction seen from transfusion?

A

Urticarial rash.

Anaphylaxis.

36
Q

What is a febrile non-haemolytic transfusion reaction?
What is the cause?
Management?

A

Fever, ± shakes, rigors, increased pulse.
Not life threatening.
Due to accumulation of cytokines during storage.
Discontinue transfusion until wrong blood/infection excluded.

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