Major haemorrhage and massive transfusion (Sources: Revision notes)

Question 1

Define major haemorrhage

Answer 1

Loss of > 1 blood volume within 24 hours
Loss of half of total blood volume within 3 hours
Bleeding rate > 150 ml/min
Bleeding with physiological derangement illustrated by SBP < 90, hr >110

Question 2

What are the definitions of massive transfusion?

Answer 2

Transfusion of > 10 units within 24 hours

Transfusion of > 1 blood volume within 24 hours

Question 3

Describe acute coagulopathy of trauma

Answer 3

Traditionally attributed to the combination of acidosis, hypothermia, dilutional with crystalloid, and RBC transfusion and consumption e.g. from DIC
More recent work suggests acute coagulopathy is the consequence of tissue hypoperfusion mediated via the protein c pathway and hyper-fibrinolysis
Associated with poor outcomes and requires early recognition and aggressive therapy

Question 4

Describe the PROPPR study

Answer 4

Holcomb et al, JAMA 2015
Compared ratios of plasma: platelets (in the UK 1 pool of plts contains 6 units of plts):RBCs 1:1:1 to 1:1:2 which showed no difference in overall mortality at 24 hours or 30 days. More pts in the 1:1:1 group achieved haemostasis within 24 hours and fewer died of exsanguination within 24 hours

Question 5

Why do you need to monitor calcium?

Answer 5

The citrate in RBCs decreases ionised calcium

Question 6

Who is at most risk of hypocalcaemia in massive transfusion situations?

Answer 6

Those with liver disease or ischaemic liver are most at risk

Question 7

What is the mechanism of action of tranexaminc acid?

Answer 7

Inhibits plasminogen and thereby inhibits fibrinolysis

Question 8

Should we use tranexamic acid in trauma?

Answer 8

CRASH-2 showed a decrease in mortality from bleeding when used early

Question 9

Discuss use of recombinant factor VII

Answer 9

Factor VII combines with platelet and tissue factor to generate a thrombin burst resulting in fibrin clot formation
High quality evidence for its use in major haemorrhage is lacking
Expensive and associated with a significant increase in the incidence of arterial thrombus
Used in some settings on a case by case basis e.g. refractory haemorrhage