Coagulopathy (Sources: Revision notes) Flashcards

1
Q

What are the potential aetiologies in ICU patients with coagulopathies?

A
DIC
Acute coagulopathy of trauma
Drugs e.g. warfarin, dabigatran, heparins
Liver disease
Renal disease
Hyper-fibrinolysis
Vitamin-K deficiency
Acidosis
Low ionised calcium
Hypothermia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How should you approach investigation of coagulopathy in an ICU patient?

A
Systematic r/v of history and examination
Coagulation screen
D-dimer
FBC and blood film
Bleeding time
B12 and foltate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the JPAC minimum recommended dose of FFP?

A

12-15mls/kg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the ‘INR’ of FFP?

A

Around 1.6

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is cryoprecipitate?

A

A rich source of fibrinogen

It also contains a significant Von Willebrands component

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

When is cryoprecipitate indicated?

A

Bleeding with acute DIC or liver disease and fibrinogen < 1.5 g/L
Prior to surgery when fibrinogen < 1.5
In the context of major haemorrhage fibrinogen should be kept > 1.4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the dose of cryoprecipitate for adults?

A

2 pooled units

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is Octaplex/ prothrombin concentrate?

A

Freeze dried preparation of clotting factors II, VII, IX, X

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the advantages of prothrombin concentrate?

A

Easier to store
Longer shelf-life
Smaller volume
Quicker to administer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the disadvantages of prothrombin concentrate?

A

Expensive

Smaller volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is DIC?

A

Defined by the International Society of Thrombosis and Haemostasis (ISTH) as an aqcuired syndrome characterised by the intravascular activation of coagulation with loss of localization arising from different causes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the most common cause of DIC?

A

Sepsis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How does DIC manifest clinically?

A

With bleeding although can present with microthrombi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What do lab findings show in DIC?

A

Hypofibrinoginaemia
Prolonged PT and APTT
Raised D-dimer
Thrombocytopenia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How is DIC managed?

A

Identification and treatment of the underlying cause and transfusion of FFP/plts if significant bleeding is encountered

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How are aspirin and clopidogrel reversed?

A

Platelet transfusion

17
Q

How is warfarin reversed?

A

Vitamin K and FFP reverse within hours

Prothrombin concentrate allows for rapid reversal

18
Q

How are novel oral anticoagulants reversed?

A

No specific reversal agents

19
Q

How is unfractionated heparin reversed?

20
Q

How is LMWH reversed?

A

Partially reverses with protamine

21
Q

How is fondaparinux reversed?

A

Nil specific agent

Recombinant factor VII in severe cases

22
Q

Describe the coagulaopthy of liver disease

A

Impaired synthetic liver function leads to a reduction in coagulation factors, this is often matched by a decrease in the production of endogenous anticoagulant
Therefore in chronic liver disease a pro-thrombotic tendency exists despite abnormal markers of clotting
In the absence of significant bleeding or thrombocytopenia patients require DVT prophylaxis

23
Q

What is activated clotting time?

A

Measure efficacy and guide titration of unfractionated heparin while using extracorporeal circuits

24
Q

What is thromboelastography (TEG)?

A

Describes the visco-elastic tendancies of whole blood
Provides information on clot strength, fibrin formation, platelet-fibrin interaction and fibrinolysis
Blood is inserted into 2 cups heated to 37 degrees
The cups then rotate around a wire inserted into the cup, leading to movement of the wire and a characteristic TEG trace is formed.
Kaolin is used to activate clotting
The platelet mapping assay can be added to provide further information regarding platelet function

25
What is rotational thromboelastometry (ROTEM)?
A visco-elastic test Similar to TEG but uses and optical system to generate trace Also uses activators to accelerate clotting - tissue factor activates the extrinsic pathway -contact factor activates the intrinsic pathway
26
What is the R time?
TEG measurement Time until initiation of fibrin formation Taken as a period to 2 min amplitude on the tracing Indicates concentration of soluble clotting factors in the plasma
27
What is clotting time?
ROTEM | Same as R time on TEG
28
What is K time?
TEG Known as clot formation time on the ROTEM Time period for the amplitude of the tracing to increase from 2 to 20mm It's a measurement of clot kinetics
29
What is the alpha angle?
Angle between a tangent to the tracing at 2mm amplitude and the horizontal midline Signifies the rapidity of fibrin build up and cross-linking
30
What is maximum amplitude?
TEG Equivalent to maximum clot formation on ROTEM Greatest vertical width achieved by the tracing reflecting maximum clot strength Signifies number and function of platelets and fibrinogen concentration
31
What is CL30?
TEG Equivalent to LY30 on ROTEM 30% reduction in amplitude 30 mins after MA Signifies clot stability and fibrinolysis