Blood Transfusions

Question 1

In which situations are packed red cells used?

Answer 1

Substantial haemorrhage

Severe anaemia

Question 2

What is FFP and in which situations is it used?

Answer 2

Fresh frozen plasma = plasma separated from fresh whole blood and frozen, containing clotting factors

Used to:

• during major haemorrhage
• replace def of coag factors in continued bleeding, e.g. liver disease, DIC, thrombotic thrombocytopenia purpura

Question 3

In which situations are platelet concentrates used?

Answer 3

Indicated if platelet count <50 x 10^9/L:

• platelet exhaustion during major haemorrhage
• thrombocytopenia

Question 4

In which situations are cryoprecipitate, fibrinogen and other specific clotting factor concentrates used?

Answer 4

In various coagulation deficiencies, e.g. haemophilia, hypofibrinogenaemia

Question 5

Which blood groups are the universal donors? The universal receivers?

Answer 5

Universal donors = O-

Universal receivers = AB+

Question 6

What would you give a patient with <30% blood volume loss?

Answer 6

Requires only crystalloids/colloids

Question 7

What would you give a patient with 30-40% blood volume loss?

Answer 7

Requires red cell transfusion

Question 8

What would you give a patient with >40% blood volume loss (>2L)?

Answer 8

Requires rapid volume replacement with crystalloids/colloids + urgent provision of blood and blood products

Question 9

Define massive blood loss. What is the clinical manifestation of this?

Answer 9

Haemorrhage of 50% blood volume in 3hrs, >1x blood volume in 24hrs or >150ml/min

Leads to a systolic pressure <90mmHg or HR >110bpm

Question 10

Describe the massive blood loss protocol

Answer 10

1. Immediate resuscitation with 4 units RBCs (O-)
2. If bleeding continues: further RBCs + FFP
3. Platelet concentrates given to maintain levels >100 x 10^9/L
4. Repeat coag screens after every 4 units to determine need for other blood products
5. If bleeding persists, recombinant activated factor VII occasionally recommended.

Question 11

A patient who has received a blood transfusion immediately has a temp rise >1 degree and starts shivering. What is the likely diagnosis? How would you manage?

Answer 11

FEBRILE NON-HAEMOLYTIC TRANSFUSION REACTION

• caused by leukocyte incompatibility
• common in multi-transfused or parous women
• symptoms subside after stopping transfusion for 15-30min and administering anti-pyretics and anti-histamines

Question 12

A patient receiving a blood transfusion develops a haemolytic transfusion reaction. Why does it occur?

Answer 12

Occurs due to: blood group incompatibility (mostly due to human error)

If major ABO incompatibility, massive haemolysis may be fatal

Incompatibility of minor determinants causes lesser degree of haemolysis

Question 13

What are the symptoms of a haemolytic transfusion reaction? How would you confirm diagnosis?

Answer 13

Symptoms:

• pyrexia
• dyspnoea and constrictive feeling in chest
• intense headache
• hypotension
• severe loin pain and acute oliguric renal failure with haemoglobinuria (obstruction of tubules with haemoglobin causing ATN)
• jaundice (hrs-days later)
• DIC with spontaneous bruising and haemorrhage

Diagnosis confirmed by blood test:

• hyperbilirubinaemia
• positive Coomb’s test
• new antibody

Question 14

How should a haemolytic transfusion reaction be managed?

Answer 14

Transfusion must be halted immediately and patient resuscitated

Oliguria treated by osmotic diuresis, e.g. mannitol +/- loop diuretic

Question 15

A patient having had a blood transfusion develops an acute and rapid onset SOB and cough. What is the diagnosis? How is this managed?

Answer 15

TRANSFUSION-RELATED ACUTE LUNG INJURY

• donor Abs reacting with Pt’s leucocytes
• especially occurs in transfusion of plasma-containing products
• usually requires intensive care and mechanical ventilation
• typically a ‘white-out’ on CXR

Question 16

1 week after a blood transfusion, a patient develops thrombocytopenia and bleeding. What is the diagnosis? How is this managed?

Answer 16

POST-TRANSFUSION PURPURA

• platelet-specific alloAbs
• most common in women
• treated with high dose IV Igs (favourable resp in 85%)

Question 17

What is blood tested for before it can be sent to the blood bank?

Answer 17

HIV

Hep B, C, E

CJD

EBV

Syphilis

Malaria

Question 18

What are the components of FFP and cryoprecipitate? And when might they be used?

Answer 18

Factor VIII, vWF, fibrinogen

Used = vonWillebrand disease, hypofibrinogenemia, pts with coagulopathy that are bleeding/at risk of bleeding

Question 19

List the possible EARLY complications of a blood transfusion

Answer 19

Acute haemolytic reaction (ABO incompatibility)

TACO - transfusion associated circulatory overload (potential in frail IHD/CCF pts)

TRALI - transfusion related acute lung injury

Allergic reaction

Infective/bacterial shock

Question 20

List the possible LATE complications of a blood transfusion

Answer 20

Infection

GvH disease

Iron overload

Question 21

What ways can Hb be increased prior to surgery?

Answer 21

EPO - takes 2-6 weeks to have an effect

Find the causes of anaemia and treat it

Question 22

What are the alternatives to a blood transfusion?

Answer 22

Blood substitutes - provide O2 carrying capacity

Exogenous EPO

Cell salvage

Question 23

Outline the potential special requirements of a blood transfusion

Answer 23

• Irradiated blood (prevent TA-GvHD)
	◦ Neonates (<1)
	◦ Chemo
	◦ Haemolytic disease
	◦ Organ transplants 

• CMV -ve products
◦ Intrauterine transfusions
◦ Neonates (<28 days)
◦ Immunosuppressed

Question 24

What is the most helpful test for identifying causes of haemolytic anaemia?

Answer 24

Direct anti-globulin test (raised LDH + bilirubin)