Blood Transfusions + Major Haemorrhage

Question 1

What temperature are red cells stored at and for how long?

Answer 1

4 degrees for 35 days

Question 2

What temperature is FFP stored at and for how long?

Answer 2

-30 degrees for 3 years

Question 3

What temperature are platelets stored at and for how long?

Answer 3

22 degrees for 7 days (with agitation)

Question 4

Which chromosome are the ABO genes found on?

Answer 4

Chromosome q

Question 5

Which blood groups are dominant?

Answer 5

A + B are co-dominant over O (O is silent)

Question 6

Which blood group is the universal donor?

Answer 6

O –> can be given to anyone

Question 7

Which blood group is the universal reciever?

Answer 7

AB –> can receive blood from any other group

Question 8

Which antigen on RBCs is next most important after ABO?

Answer 8

RhD

Question 9

How is ABO/RhD grouping determined?

Answer 9

1. Test patient’s red cells with anti-A, anti-B and anti-D
   - direct agglutination
2. Test patient’s plasma against red cells of group A and group B
   - -> define blood group
3. Antibody screening: patient’s plasma + red cells with a range of antigens
   - indirect antiglobulin test (add anti-human Ig)

Question 10

What are the indications for a red cell transfusion?

Answer 10

SYMPTOMATIC anaemia Hb < 70 (< 80 if cardiac disease)

Major bleeding

Question 11

What are the indications for a platelet transfusion?

Answer 11

Prophylaxis in patients with bone marrow failure + very low platelets
Treatment of bleeding in thrombocytopenic patient
Prophylaxis prior to surgery in thrombocytopenic patient

Question 12

What is the difference between platelets and FFP?

Answer 12

Platelets = primary homeostasis
FFP = clotting factors from coagulation cascade = secondary homeostasis

Question 13

What are the indications for FFP transfusion?

Answer 13

Treatment of bleeding or surgical prophylaxis in patient with coagulopathy (PT ratio > 1.5)
Management of massive haemorrhage

Question 14

What are the symptoms and signs of an acute transfusion reaction?

Answer 14

Symptoms:
- chills, rigors
- rash, flushing
- feeling of impending doom
- collapse
- loin pain
- respiratory distress
Signs:
- fever
- tachycardia
- hypotension

Question 15

What is the differential for an acute transfusion reaction?

Answer 15

Acute haemolytic transfusion reaction

Bacterial contamination of blood products

Question 16

What are the principles of management for all acute transfusion reactions?

Answer 16

1. STOP the transfusion
2. Assess patient with ABCDE
3. Re-check compatibility tag against patient details and inspect bag for evidence of contamination
4. Document event in medical notes

Question 17

What causes an acute haemolytic transfusion reaction?

Answer 17

ABO incompatible blood transfusion (most dangerous) or other antigen
Binding of IgM anti-A or anti-B to their corresponding antigens
–> intravascular haemolysis of transfused red cells + release of inflammatory cytokines

Question 18

What are the features of an acute haemolytic transfusion reaction?

Answer 18

Shock
Increased vascular permeability
DIC 
Renal failure
--> often fatal

Question 19

Which type of blood product is most likely to contain bacterial contamination?

Answer 19

Platelets (stored at warmest temperature)

Question 20

How should a suspected bacterial contamination transfusion reaction be managed?

Answer 20

Stop transfusion
ABCDE
Culture patient + remains of unit
Broad spectrum antibiotics
Need to inform transfusion lab so that other units can be quarantined

Question 21

What are the features of transfusion related circulatory overload (TACO)?

Answer 21

Respiratory distress within 6 hours of transfusion
Raised BP and raised JVP
Positive fluid balance

Question 22

What are the risk factors for TACO?

Answer 22

Elderly
Cardiac failure
Low albumin
Renal impairment
Fluid overload

Question 23

How should a patient with TACO be managed?

Answer 23

Oxygen + diuretics
Slow rate of further transfusions
Only transfuse minimum volume required
–> identify patients at risk before transfusion

Question 24

Give two examples of mild transfusion reactions?

Answer 24

Febrile non-haemolytic transfusion reaction

Mild allergic reaction

Question 25

What are the features of a febrile non-haemolytic transfusion reaction?

Answer 25

Isolated temperature rise > 38 degrees or rise of 1-2 degrees

Question 26

What are the features of a mild allergic transfusion reaction?

Answer 26

Rash/itch but normal observations

Question 27

How should a mild transfusion reaction be managed?

Answer 27

Slow rate of transfusion
Close monitoring in case condition worsens
Consider paracetamol/anti-histamine

Question 28

What is a delayed haemolytic transfusion reaction?

Answer 28

Extravascular haemolysis 5-10 days post-transfusion

Question 29

How is a delayed haemolytic transfusion reaction diagnosed?

Answer 29

Drop in Hb
Rise in bilirubin
+ve DAT (direct Coombs’) + detection of allo-antibody

Question 30

How is major haemorrhage defined?

Answer 30

Volume + rate of blood loss:

• one blood volume in 24 hours
• blood loss of 150ml/min
• obstetrics: major = >1000ml

Or by clinical situation:

• HR > 110 +/- systolic BP < 90
• bleeding which has already prompted use of emergency O neg red cells

Question 31

What are the initial steps of the major haemorrhage protocol?

Answer 31

Call blood bank and state 'major haemorrhage'
Send urgent blood samples:
- FBC, coag, fibrinogen, crossmatch, U&Es, calcium
Blood bank will issue:
- 4 units red cells
- 4 units FFP
- 1 unit platelets
Resus --> ABCDE

Question 32

What should be done if there is ongoing bleeding following the initial steps of the major haemorrhage protocol?

Answer 32

Repeat blood samples
Transfuse further RBCs + FFP at rate of 2:1 (1:1 in trauma)
Cryoprecipitate if fibrinogen < 1
Consider further platelets

Question 33

What does cryoprecipitate do?

Answer 33

Replaces fibrinogen

Question 34

Which bleeding situations have specific management protocols?

Answer 34

Post partum haemorrhage
Trauma
Variceal bleed
Ruptured AAA