Basic Clinician Training
Module 2
TEG® Technology
Review of the Hemostatic Process
Hemostasis Monitoring with the TEG Analyzer
How the TEG Analyzer Monitors Hemostasis
Parameters
Tracings
Blood Sample Types and Preparation
Test Your Knowledge
Hemostatic Process
Area of Injury
Endothelium damaged
Collagen
ADP
XII
Platelet
AA
XIIa
XI
Coagulation Cascade
Platelet plug formed
(white clot)
Change in
Endothelial Cells
Platelet Shape
XIa
IX
VIIa / TF
VII
X
+
Thrombin generated on
platelet surface
V
Ca2+
V
Pr
ombin (II)
Thr
XIII
tPA
Plasminogen
Plasmin
Fibrin Strands
Degradation Products
Clot lysis
Fibrinolysis
Platelet-fibrin plug formed
(red clot)
XIIIa
Routine Coagulation Tests:
PT, aPTT, Platelet Counts
•
•
Based on cascade model of coagulation
 Measure protein interaction in plasma (thromboplastin)
 Exclude cellular contributions (platelets, monocytes, etc.)
 Determine adequacy of coagulation factor levels
Use static endpoints
 Ignore altered thrombin generation
 Ignore cellular elements
 Ignore overall clot structure
Hemostasis Monitoring:
TEG Hemostasis System
•
•
•
Whole blood test
Measures hemostasis
 Clot initiation through clot lysis
 Net effect of components
TEG system




Laboratory based
Point of care
Remote, can be networked
Flexible to institution needs
The TEG Analyzer:
Description
•
•
•
Reflects balance of the hemostatic system
Measures the contributions and interactions of
hemostatic components during the clotting process
Uses activated blood to maximize thrombin generation
and platelet activation in an in vitro environment
 Measures the hemostatic potential of the blood at a given
point in time under conditions of maximum thrombin
generation
TEG Technology
The TEG Analyzer
How It Works
TEG Technology:
How It Works
• Cup oscillates
• Pin is attached to a
•
•
•
•
torsion wire
Clot binds pin to cup
Degree of pin
movement is a
function of clot kinetics
Magnitude of pin
motion is a function of
the mechanical
properties of the clot
System generates a
hemostasis profile
 From initial formation
to lysis
Utility of TEG Analysis
•
•
Demonstrates all phases of hemostasis
 Initial fibrin formation
 Fibrin-platelet plug construction
 Clot lysis
Identifies imbalances in the hemostatic system
 Risk of bleeding
 Risk of thrombotic event
Amplitude of pin oscillation
What TEG Analysis Captures
Time
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TEG Parameters
Identification
Definition
Thrombin Formation (Clotting Time)
The R Parameter: Identified
Initial fibrin
formation
Intrinsic,
extrinsic,
common
pathways
Pin is
engaged
Pin is
stationary
Reaction time
Fibrin creates a
connection between
cup and pin
Amplitude of
pin oscillation
•
•
Time
Cup oscillates,
pin remains
stationary

Pin starts to
oscillate with
cup
Thrombin Formation
The R Parameter: Defined
•
Initial fibrin
formation
Intrinsic,
extrinsic,
common
pathways
Pin is
engaged
Pin is
stationary
Cup oscillates,
pin remains
stationary

Pin starts to
oscillate with
cup
•
Time until formation of
critical mass of
thrombin
Expression of
enzymatic reaction
function (i.e. the ability
to generate thrombin
and fibrin)
Thrombin Formation Abnormalities
The R Parameter: Elongated R
•
Initialfibrin
fibrin
Initial
formation
formation
•
•
Pin is
stationary
Pin is
engaged
Possible causes of
imbalance:
 Slow enzymatic
reaction
Possible etiologies:
 Factor deficiency/
dysfunction
 Residual heparin
Common treatments:
 FFP
 Protamine
Thrombin Formation Abnormalities
The R Parameter: Short R
• Possible causes of
Initial fibrin
formation
•
•
Pin is
engaged
Pin is
stationary
imbalance:
 Over-stimulated
enzymatic reaction
 Fast fibrin
formation
Possible etiologies:
 Enzymatic
hypercoagulability
Common treatments:
 Anticoagulant
Fibrinogen
The α (Angle) Parameter: Identified
•
Fibrin
increases
Baseline
Pin is
engaged
Rate of increase in pin
oscillation amplitude
as fibrin is generated
and cross-links are
formed
Fibrinogen
The α (Angle) Parameter: Defined
• Kinetics of clot formation
Fibrin
increases
Baseline
Pin is
engaged
 Rate of thrombin
generation
 Conversion of
Fibrinogen  fibrin
 Interactions among
fibrinogen, fibrin,
and platelets
 Cellular
contributions
Fibrinogen Abnormalities
The α (Angle) Parameter: Low a
•
Fibrin
increases
•
Baseline
Pin is
engaged
•
Possible causes of
imbalance:
 Slow rate of fibrin
formation
Possible etiologies:
 Low fibrinogen levels or
function
 Insufficient rate/amount
of thrombin generation
 Platelet
deficiency/dysfunction
Common treatments:
 FFP
Cryoprecipitate
Fibrinogen Abnormalities
The α (Angle) Parameter: High a
•
Fibrin
increases
•
Baseline
•
Possible causes of
imbalance:
 Fast rate of fibrin
formation
Possible etiologies:
Platelet
hypercoagulability
Fast rate of thrombin
generation
Common treatments:
 None
Pin is
engaged
Platelet Function
The MA Parameter: Defined
Maximum amplitude (MA)
of pin oscillation
•
•
•
Amplitude of
pin oscillation
Maximum amplitude
Clot strength = 80%
platelets + 20%
fibrinogen
Platelet function
influences thrombin
generation and fibrin
formation 
relationship between
R, α, and MA
Platelet Function Abnormalities
The MA Parameter: Low MA
Maximum amplitude (MA)
of pin oscillation
•
•
Amplitude of
pin oscillation
•
Possible causes:
 Insufficient plateletfibrin clot formation
Possible etiologies:
 Poor platelet function
 Low platelet count
 Low fibrinogen levels
or function
Common treatments:
 Platelet transfusion
Platelet Function Abnormalities
The MA Parameter: High MA
Maximum amplitude (MA)
of pin oscillation
•
•
•
Amplitude of
pin oscillation
Possible causes:
 Excessive platelet
activity
Possible etiologies:
 Platelet
hypercoagulability
Common treatments:
 Antiplatelet agents
Note: Should be
monitored for efficacy
and/or resistance
(See Module 6:
Platelet Mapping)
Coagulation Index
The CI Parameter: Defined
•
•
Global index of
hemostatic status
Linear combination of
kinetic parameters of
clot development and
strength (R, K, angle,
MA)
CI > +3.0:
hypercoagulable
CI < -3.0:
hypocoagulable
Fibrinolysis: LY30 and EPL
LY30 and EPL Parameters: Identified
•
•
MA
30 min
LY30 is the percent
decrease in amplitude
of pin oscillation 30
minutes after MA is
reached
Estimated percent
lysis (EPL) is the
estimated rate of
change in amplitude
after MA is reached
Fibrinolysis: LY30 and EPL
LY30 and EPL Parameters: Defined
•
MA
30 min
Reduction in
amplitude of pin
oscillation is a
function of clot
strength, which
depends on extent
of fibrinolysis
Fibrinolytic Abnormalities
LY30 Parameter: Primary Fibrinolysis
•
•
•
Possible causes:
 Excessive rate of
fibrinolysis
Possible etiologies:
 High levels of tPA
Common treatments:
 Antifibrinolytic agent
Fibrinolytic Abnormalities
LY30 Parameter: Secondary Fibrinolysis
•
Possible causes:
 Rapid
•
rate of clot
formation/breakdown
Possible etiologies:
 Microvascular
hypercoagulability
(i.e. DIC)
DIC = disseminated intravascular coagulation
Fibrinolytic Abnormalities
LY30 Parameter: Secondary Fibrinolysis
•
Possible causes:
 Rapid
•
rate of clot
formation/breakdown
Possible etiologies:
 Microvascular
•
hypercoagulability
(i.e. DIC)
Common treatments:
 Anticoagulant
DIC = disseminated intravascular coagulation
Clot Strength:
The G Parameter
•
•
Representation of clot strength and overall
platelet function
 G = shear elastic modulus strength (dyn/cm2)
 G = (5000*MA)/(100-MA)
Relationship between clot strength and platelet
function
 MA = linear relationship between clot strength and
platelet function
 G = exponential relationship between clot strength and
platelet function
• More sensitive to changes in platelet function
MA vs. G
(Kaolin Activated Sample)
30.0
Normal MA range
(Kaolin activated)
25.0
2) x 1000
G(dynes/cm
G (d yn s/cm2
)
Hyperactive platelet function
20.0
15.0
Normal platelet function
10.0
Hypoactive platelet function
5.0
0.0
5
10
15
20
25
30
35
40
45
MA (mm)
50
55
60
65
70
75
80
85
TEG Parameter Summary:
Definitions
Clotting
Time
R
The latency period from the time that the blood was placed in the TEG®
analyzer until initial fibrin formation. Represents enzymatic reaction.
K
A measure of the speed to reach 20 mm amplitude. Represents clot
kinetics.
Clot
Kinetics
A measure of the rapidity of fibrin build-up and cross-linking (clot
Alpha strengthening). Represents fibrinogen level.
Clot
Strength
Coagulation
Index
Clot
Stability
MA
A direct function of the maximum dynamic properties of fibrin and platelet
bonding via GPIIb/IIIa. Represents maximum platelet function.
G
A transformation of MA into dyn/cm2.
CI
A linear combination of R, K, alpha, MA.
LY30
EPL
A measure of the rate of amplitude reduction 30 min.after MA.
Estimates % lysis based on amplitude reduction after MA.
TEG Parameter Summary
Platelet function
Clot strength
(G)
Clotting
time
Clot
kinetics
Clot stability
Clot breakdown
Basic Clinician Training
TEG Results
Tracings
Data
Decision Tree
Components of the TEG Tracing
Example: R
Amplitude of
pin oscillation
Actual
value
Normal range
Parameter
Units
Value
Normal range
Time
“Normal” TEG Tracing
30 min
Hemorrhagic TEG Tracing
30 min
Prothrombotic TEG Tracing
30 min
Fibrinolytic TEG Tracing
30 min
TEG Decision Tree
Qualitative
TEG Decision Tree
Quantitative
Hemorrhagic
Fibrinolytic
US Patent 6,787,363
Thrombotic
TEG Tracing
Example: Hemorrhagic
TEG Tracing
Example: Prothrombotic
TEG Tracing
Example: Fibrinolytic
Basic Clinician Training
TEG Blood Sampling
TEG Blood Sampling
•
Blood samples
 Arterial or venous
 Samples should be consistent
TEG Blood Sampling
Native
•
Non-modified blood samples
 Assayed 4 minutes
 TEG software based upon assay at 4 minutes
TEG Blood Sampling
Modified
•
Activator
 Reduces variability
 Reduces running time
 Maximizes thrombin generation
•
•
Kaolin
 Activates intrinsic pathway
 Used for normal TEG analysis
Tissue factor
 Specifically activates extrinsic pathway
TEG Blood Sampling
Heparin
•
Heparinase
 Neutralizes heparin
 Embedded in specialized (blue) cups and pins
TEG Blood Sampling
Citrated
•
•
•
•
Citrated tubes are used
Recalcified before analysis
Standardize time between blood draw and running test
Specific platelet activators are required to demonstrate
effect of antiplatelet agents
Sample Type Designations
Whole blood + kaolin
Sample type
Conditions
Wait time
before run
sample
K
No
anticoagulation
< 6 min
(recommended
4 min)
Clear cup & pin
With heparin
< 6 min
(recommended
4 min)
Blue cup & pin (coated
with heparinase)
(kaolin activated)
KH
(kaolin + heparinase)
CK
With citrate
> 6 min
< 120 min
Add calcium chloride
Clear cup and pin
With citrate
and heparin
> 6 min
< 120 min
Add calcium chloride
Blue cup & pin
(citrate + kaolin)
CKH
(citrate + kaolin +
heparinase)
Sample prep
Summary
•
•
The TEG technology measures the complex balance
between hemorrhagic and thrombotic systems.
The decision tree is a tool to identify coagulopathies
and guide therapy in a standardized way.
Basic Clinician Training
TEG Parameters
Hemostasis Monitoring
Test your knowledge of TEG parameters and
hemostasis monitoring by answering the questions on
the slides that follow.
Exercise 1: TEG Parameters
The R value represents which of the following
phases of hemostasis?
a. Platelet adhesion
b. Activation of coagulation pathways and initial fibrin
formation
c. Buildup of platelet-fibrin interactions
d. Completion of platelet-fibrin buildup
e. Clot lysis
Answer: page 64
Exercise 2: TEG Parameters
Select the TEG parameters that demonstrate
kinetic properties of clot formation. (Select all that
apply)
a.
b.
c.
d.
e.
R
Angle (a)
MA
LY30
CI
Answer: page 65
Exercise 3: TEG Parameters
The rate of clot strength buildup is demonstrated
by which of the following TEG parameters?
a.
b.
c.
d.
e.
R
Angle (a)
MA
LY30
CI
Answer: page 66
Exercise 4: TEG Parameters
Which of the following TEG parameters will best
demonstrate the need for coagulation factors
(i.e. FFP)?
a.
b.
c.
d.
e.
R
Angle (a)
MA
LY30
CI
Answer: page 67
Exercise 5: TEG Parameters
Clot strength is dependent upon which of these
hemostatic components?
a.
b.
c.
d.
e.
100% platelets
80% platelets, 20% fibrin
50% platelets, 50% fibrin
20% platelets, 80% fibrin
100% fibrin
Answer: page 68
Exercise 6: TEG Parameters
Which of the following TEG parameters
demonstrate a structural property of the clot?
(Select all that apply)
a.
b.
c.
d.
e.
R
Angle (a)
MA
LY30
CI
Answer: page 69
Exercise 7: TEG Parameters
Because the TEG is a whole blood hemostasis monitor, a
low MA demonstrating low platelet function may also
influence which of the following TEG parameters?
(Select all that apply)
a.
b.
c.
d.
e.
R
Angle (a)
LY30
CI
None of the above
Answer: page 70
Exercise 8: TEG Parameters
Clot stability is determined by which of the following
TEG parameters?
a.
b.
c.
d.
e.
R
Angle (a)
MA
LY30
CI
Answer: page 71
Exercise 9: TEG Parameters
Which of the following reagents should be used to provide
the information necessary to determine if heparin is the
cause of bleeding in a patient?
a.
b.
c.
d.
R value: Kaolin with heparinase
R value: Kaolin vs. Kaolin with heparinase
MA value: Kaolin with heparinase
MA value: Kaolin vs. kaolin with heparinase
Answer: page 72
Exercise 10: TEG Parameters
Which of the following parameters provides an indication
of the global coagulation status of a patient?
a.
b.
c.
d.
e.
R
Angle (a)
MA
LY30
CI
Answer: page 73
Exercise 11: TEG Parameters
Which of the following statements are true regarding the
PT and aPTT tests? (select all that apply)
a. Measure coagulation factor interaction in solution
b. Measure platelet contribution to thrombin generation
c. Measure the influence of thrombin generation on
platelet function
d. Use fibrin formation as an end point
Answer: page 74
Exercise 12: TEG Parameters
The TEG analyzer can monitor all phases of hemostasis
except which of the following? (select all that apply)
a.
b.
c.
d.
Initial fibrin formation
Fibrin-platelet plug construction
Platelet adhesion
Clot lysis
Answer: page 75
Answers to Exercise 1: TEG
Parameters
The R value represents which of the following
phases of hemostasis?
a. Platelet adhesion
b. Activation of coagulation pathways and initial
fibrin formation
c. Buildup of platelet-fibrin interactions
d. Completion of platelet-fibrin buildup
e. Clot lysis
Answers to Exercise 2: TEG
Parameters
Select the TEG parameters that demonstrate
kinetic properties of clot formation. (select all that
apply)
a.
b.
c.
d.
e.
R
Angle (a)
MA
LY30
CI
Answers to Exercise 3: TEG
Parameters
The rate of clot strength buildup is demonstrated
by which of the following TEG parameters?
a.
b.
c.
d.
e.
R
Angle (a)
MA
LY30
CI
Answers to Exercise 4: TEG
Parameters
Which of the following TEG parameters will best
demonstrate the need for coagulation factors
(i.e. FFP)?
a.
b.
c.
d.
e.
R
Angle (a)
MA
LY30
CI
Answers to Exercise 5: TEG
Parameters
Clot strength is dependent upon which of these
hemostatic components?
a.
b.
c.
d.
e.
100% platelets
80% platelets, 20% fibrin
50% platelets, 50% fibrin
20% platelets, 80% fibrin
100% fibrin
Answers to Exercise 6: TEG
Parameters
Which of the following TEG parameters
demonstrate a structural property of the clot?
(select all that apply)
a.
b.
c.
d.
R
Angle (a)
MA (demonstrates maximum clot strength)
LY30 (demonstrates clot breakdown or the
structural stability of the clot)
e. CI
Answers to Exercise 7: TEG
Parameters
Because the TEG is a whole blood hemostasis monitor, a low
MA demonstrating low platelet function may also influence
which of the following TEG parameters? (select all that apply)
a. R – Thrombin generation occurs mainly on the surface of
platelets; therefore, a defect in platelet function may slow
the rate of thrombin generation and fibrin formation.
b. Angle (a) – A defect in platelet function may slow the rate
of formation of platelet-fibrin interactions, thereby slowing
the rate of clot buildup.
c. LY30
d. CI
e. None of the above
Answers to Exercise 8: TEG
Parameters
Clot stability is determined by which of the following
TEG parameters?
a.
b.
c.
d.
e.
R
Angle (a)
MA
LY30
CI
Answers to Exercise 9: TEG
Parameters
Which of the following reagents should be used to provide
the information necessary to determine if heparin is the
cause of bleeding in a patient?
a.
b.
c.
d.
R value: Kaolin with heparinase
R value: Kaolin vs. Kaolin with heparinase
MA value: Kaolin with heparinase
MA value: Kaolin vs. kaolin with heparinase
Answers to Exercise 10: TEG
Parameters
Which of the following parameters provides an indication
of the global coagulation status of a patient?
a.
b.
c.
d.
e.
R
Angle (a)
MA
LY30
CI (Coagulation Index — a linear combination of the R,
K, angle, and MA)
Answers to Exercise 11: TEG
Parameters
Which of the following statements are true regarding the
PT and aPTT tests? (select all that apply)
a. Measure coagulation factor interaction in solution
b. Measure platelet contribution to thrombin generation
c. Measure the influence of thrombin generation on
platelet function
d. Use fibrin formation as an end point
Answers to Exercise 12: TEG
Parameters
The TEG analyzer can monitor all phases of hemostasis
except which of the following? (select all that apply)
a. Initial fibrin formation
b. Fibrin-platelet plug construction
c. Platelet adhesion — this is a vascular mediated event
that occurs in vivo, but not in vitro
d. Clot lysis
Basic Clinician Training
End of Module 2