Thromboelastography Flashcards Preview

I&M for Anesthesia - Fall 2013 > Thromboelastography > Flashcards

Flashcards in Thromboelastography Deck (30):
0

A thromboelastography analyzes measures the ability of a clot to

Mechanically impede hemorrhage

1

Most of the strength of a clot comes from

Platelets
75-85%

2

What produces the final clot?

Fibrin strand and activated platelets which form fibrin-platelet bonding

3

During vascular recovery, the clot gradually

Dissolves

4

Look at all the pictures

Do it now

5

R measures the time of latency between time that blood was placed in analyzer to

Initial fibrin formation

6

What does a longer R mean?

It takes longer than normal for the first fibrin strand to be formed
Represents a factor deficiency

7

An elongated R can be corrected using

Fresh frozen plasma

8

Alpha measures the _________ of fibrin build up and crosslinking

Rapidity
The speed of clot strengthening

9

K measures the rapidity of

Reaching a certain clot strength

10

Where is the clot strength measured?

20 mm amplitude

11

A direct function of the maximum dynamic properties of fibrin and platelet bonding via GPIIb/IIIa and represents the ultimate strength of the fibrin clot

Maximum Amplitude (MA)

12

Determines the rate of clot build up

Fibrinogen

13

Enables cross linking

Factor XIII (rarely deficient)
Platelets, to a lesser extent

14

An elongated K and reduced alpha can be corrected by administering

CRYO (contains both platelets and factor XIII)

15

Small MA represents ______ and can be corrected by

Thrombocytopenia (platelet dysfunction)
Administering platelets

16

There is a compensatory effect between

Fibrinogen level and platelets

17

Platelets are affected by most, if not all

Cardiac surgical procedures
So with small MA, infusion with platelets alone will correct the coagulopathy

18

LY30 measures?

Stability of the clot
Rate of amplitude reduction 30 min after MA

19

A linear combination of R, alpha, K, and MA is given by

Coagulation Index (CI)

20

Mechanical bleeding is due to _______ and shows _______ TEG parameters

Vascular injury
Normal

21

Pathophysiological bleeding is an imbalance between anticoagulant and _____ of the hemodynamics system

Prothrombotic

22

Hyperfibrinolysis is represented by

LY30 greater than 7.5%
Can be corrected by antifibrinolytic drugs

23

Probable causes of bleeding and their treatments

Vessel injury: suture
vWF deficiency: DDAVP
Presence of platelet inhibitor: run platelet mapping

24

A bleeding patient with an abnormally long R value probably has

An enzymatic pathway abnormality
Can also cause abnormalities in angle and MA

25

Inhibition or dysfunction of platelet receptors

Activation

26

Inhibition or dysfunction of GPIb receptor, preventing adhesion of platelet to endothelium

Adhesion

27

Inhibition or dys of GPIIb/IIIa receptors preventing the development of platelet plug

Aggregation

28

Inhibition or dys of of secretory pathway resulting in reduced platelet activation

Secretion

29

Reduction of thrombin generation on platelet surface

Procoagulant activity