Haematology in Trauma

Question 1

What are the advantages of ROTEM for guiding MTP?

Answer 1

• Targeted blood component delivery and potentially less overall product use
• Less overall product use may avoid complications ie thermodilution, haemodilution, coagulopathy
• Directed correction of specific coagulopathies can allow use of not blood products (ie with TXA)

Question 2

What are the disadvantages of ROTEM for guiding MTP?

Answer 2

• Requires regular sampling and interpretation
• Requires specific equipment and knowledge to interpret
• Active thinking as opposed to protocol driven (pro or con depending)

Question 3

What are some of the complications of MTP?

Answer 3

TACO
Thermodilution
Haemdilution
Dilutional coagulopathy
Hypocalcaemia/magnesaemia
Citrate toxicity
HAGMA
Potential for ABO incompatibility or air embolism if done incorrectly

Question 4

What is the arbitrary definition of massive transfusion in trauma?

Answer 4

• > 10 units of the equivalent of whole blood (different factors combined) or PRBC’s over the space of 24hrs
• This equates to approximately 1 whole blood volume in a 70kg male
  OR
• Half the blood volume in 4hrs

Question 5

What is the lethal triad?

Answer 5

Acidosis, coagulpathy and hypothermia

Question 6

What are the causes of the trauma induce coagulopathy (TIC) AKA cute traumatic coaglopathy (ATC)?

Answer 6

Shock + tissue injury = TIC

Hypothermia
Acidosis
Hypocalcaemia
Haemodilution
Consumption of clotting factors

Question 7

What is the importance of citrate in MTP?

Answer 7

Citrate is an anticoagulant used in blood product storage, FFP has the highest concentration
Citrate binds calcium and magnesium, in large transfusions citrate levels may become significant leading to severe hypomagnesaemia and hypocalcaemia

Citrate is rapidly metabolised by the liver and slowing the transfusion in itself may raise the mag/calc levels

In a trauma setting calcium should be checked regularly and replaced if levels <1.1mmol/L

Question 8

How are the results interpreted in TEG and ROTEM?

Answer 8

Question 9

What do the variables mean in TEG and ROTEM?

Answer 9

Question 10

What does a typical TEG/ROTEM trace waveform look like?

Answer 10

Question 11

What are the complications arising from giving crystalloids in trauma?

Answer 11

Dilutional coagulopathy
Clot displacement
Cardiac dysfunction
Abdominal compartment syndrome
Exacerbates SIRS
ARDS
Multi-organ failure

Has been shown to increase mortality

Question 12

What is the general principles of fluid resus in trauma?

Answer 12

• Max 1L of crystalloid
• 1:1:1 blood products initially
• If ROTEM/TEG/coags then can target blood products thereafter
• Warm the fluids
• Before cross match give 0-ve/+ve for males/post menopausal females and ideally O-ve for young females
• If no head injury aim systolic >90 or MAP >65, alternatively can titrate to palpable radial pulse or normal mentation
• If head injury aim systolic >100

Question 13

What is the reversal for warfarin in haemorrhage?

Answer 13

• 25-50U/Kg IV of Prothrombinex
• 10mg IV Vitamin K
• FFP 150-300mls (10-20mls/kg)

Question 14

What is an appropriate algorithm for use of ROTEM/TEG in trauma?

Answer 14

Question 15

With ROTEM, how are FIBTEM and EXTEM interpreted?

Answer 15

Question 16

How does the ROTEM/TEG diagram typically appear?

Answer 16

Question 17

What crossmatching is required for different blood products?

Answer 17

• PRBC requries ABO/Rh
• FFP/cryoprecipitate needs ABO but no RH
• FFP and cryo can also transfer blood borne infections

Question 18

What is in cryoprecipitate?

Answer 18

• Large amounts of Fibrinogen
• Factor VIII (8)
• Factor XIII (13)
• Von-Willebrand factor

Question 19

What are the potential complications of MTP?

Answer 19

Question 20

What are the end points of MTP resuscitation?

Answer 20