Transcript Overview of Thromboelastography (TEG) and Brief Review of

Overview of
Thromboelastography (TEG) and
Brief Review of New
Anticoagulants
Lisa Guerrini, MS, CRNA
Disclosure
Staff CRNA at William Beaumont Hospital- Troy
No conflicts to report
*I am NOT an “expert”*
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Objectives
Review Basics of Hemostasis
Understand the History and Principals of Thromboela
Identify Applications of TEG in Anesthesia
Overview and Updates of Current Anticoagulants
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Hemostasis
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aPTT
PT/INR
Routine coagulation tests (RCoT)
[PT, INR, aPTT]
 Developed 50+ years ago to monitor hemophilia
 Clot Strength
 Platelets are responsible for 80% of clot strength
 PT and INR only represent <3% of overall clot strength
 aPTT represents <10% of clot strength
 Thrombin
 PT, INR or aPTT stop where fibrin strands begin to form
 Represents <5% of overall thrombin production; much
more thrombin is needed to produce a stable network of
platelet-fibrin polymers
What is Thromboelastography?
 Assessment of viscoelastic properties of clot formation in
WHOLE blood
 1948: Dr. Hellmut Hartert
 1996: thromboelastograph® and TEG® became registered
trademarks of the Hemoscope Corp.
 Rotational Thromboelastography (”ROTEM”) manufactured
by Pentapharm GmbH
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TEG®
http://www.haemonetics.com
“K”
3-6 min
7.5-15 min
45-55
50-60mm
Normal
Hypocoagulable
Hypercoagulable
Primary Hyperfibrinolysis
Cause
Treatment R Value
K and  
angle
MA
Lack of
surgical
hemostasis
Sutures
Normal
Normal
Hemodilution
Product
High
instead of
Crystalloid/Coll
oid
Normal
Normal
Factor
Deficiency
FFP
Low or Normal Low or Normal
Fibrinogen
Deficiency
Cryoprecipitate Normal
High
Low
Low or Normal
Normal
Normal
Low
Antifibrinolytics Normal
Normal
Low
Low/dysfunctio Platelets
nal platelets
Primary
Fibrinolysis
Normal
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adapted from http://www.aana.com/newsandjournal/Documents/thromboelastography-guide-trans-0413-p127-132.pdf
TEG® Platelet MappingTM Assay
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TEG® Platelet Mapping™ result.
Normal
T. C. Collyer et al. Br. J. Anaesth. 2009;102:492-498
© The Author [2009]. Published by Oxford University Press on behalf of The Board of Directors of
the British Journal of Anaesthesia. All rights reserved. For Permissions, please email:
[email protected]
TEG® Platelet Mapping™ result.
T. C. Collyer et al. Br. J. Anaesth. 2009;102:492-498
© The Author [2009]. Published by Oxford University Press on behalf of The Board of Directors of
the British Journal of Anaesthesia. All rights reserved. For Permissions, please email:
[email protected]
Number
of
patients
Study
Type of
patients
Shore-Lesserson
et al (1999)
Cardiac
Surgery
106
Patients with TEG assays
received less FFP and PLT
transfusions postoperatively than
did RCoT patients
Manikappa et al
(2001)
Cardiac
Surgery
150
TEG better predicted postoperative
hemorrhage and significantly
decreased the need for transfusion
of PRBC, FFP, and PLT compared
to RCoT
Johansson et al
(2009)
Massively
bleeding, 21%
trauma
832
Patients treated according to
TEG had significantly lower
mortality compared to
controls (20% v. 30%)
Plotkin et al
(2008)
Trauma
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Maximum amplitude (MA)
correlated more strongly with
24hour transfusion requirements
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than standard RCoT
Conclusions
Perioperative Treatment Algorithm for Bleeding Burn Patients
Reduces Allogeneic Blood Product Requirements
E. Scahden, O. Kimberger, P. Kraincuk, D.M. Baron, P.G. Metnitz and S.
Kozek-Longnecker
British Journal of Anaesthesia, 2012
 Prospective, Randomized, Controlled, single centre study
 Patients (30) undergoing surgical excision of burn wounds on
third day following burn trauma
• Control Group (16): Coagulation management according to clinician’s
discretion; included administration of FFP, PLT concentrate, fibrinogen
concentrate, prothrombin complex concentrate and tranexamic acid
according to clinical judgement; routine coagulation tests as needed
• Algorithm Group (14): ROTEM analysis, intervention per preset algorithm
 Hypothesis: Rapid correction of coagulopathy will decrease
allogeneic blood product transfusions during surgical excision of
burn wounds
Algorithm-
based on Austrian Task Force of Perioperative Coagulation
ROTEM 1:
EXTEM= initial activation and dynamics of clot formation, allows analysis of factor deficiencies
Maximum clot firmness (MCF) of EXTEM= clot strength and stability, very dependent on PLT count and
fibrinogen function
Clot strength after 10minutes (A10)= high correlation to MCF, just available faster!
FIBTEM is the same test as EXTEM, just has a PLT inhibitor added
FIBTEM MF or A10 represent the contribution of fibrinogen to clot strength
APTEM is the same test as EXTEM, just has aprotinin (trasylol) added
Improvement in prolonged clotting time (CT) and/or reduced MCF diagnose Hyperfibrinolysis
R value/Clot Strength K +  angle
Maximum Amplitude
Lysis Time
CTex>100s
A10EX<45mm
A10AP>A10EX
A10FIB>12mm
LY30ex>10%
(problem=PLT)
(problem=clot lysis)
A10EX<45mm
(problem=inability to A10FIB<12mm
form clots)
(problem=fibrinogen)
FFP
4units
Fibrinogen (2g)
Platelets
(1u)
Tranexamic Acid
(10mg/kg)
ROTEM was preformed preop, intraop and postop in the ICU until the morning after
surgery
Outcomes
 Primary
• Cumulative number of allogeneic blood units
(PRBC, FFP, and PLT concentrates) transfused
on the day of the surgical excision of burn
wounds
 Secondary
• The use of PRBCs alone, FFP alone, PLT
concentrate alone, Prothrombin complex
concentrate alone, and tranexamic acid
Control
(units/pt)
Algorithm
(units/pt)
P value
Allogeneic Blood
Product
10.2
3.1
0.002
PRBC
alone
4.8
3.1
0.12
FFP
alone
5
None given
<0.001
Platelet
Concentrate
alone
Overall- 4units
None given
0.12
Fibrinogen
concentrate
8g
8g
0.89
No prothrombin concentrate complex or transexamic acid
were give to either group
“New” Anticoagulants
 Prasugrel
 Effient®
 Dabigatran
 Pradaxa®
 Rivaroxaban
 Xarelto®
 Ticagrelor
 Brilinta®
 Apixaban
 Eliquis®
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Prasugrel (Effient)
•
•
•
•
•
FDA approved to reduce the risk of MI in angioplasty
P2Y12 Receptor antagonist
Single 60mg loading dose; 10mg daily maintenance
Time to peak effect: 1hr
Metabolism
CYP450
- Primarily CYP3A4 and CYP2B6
- Lesser extent CYP2C9 and CYP2C19
• Elimination
- Half life: 7.4hrs
- 68% Renal
- 27% Fecal
• Recommended coagulation
assay: PLT mapping
• Reversal: PLTs
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Dabigatran (Pradaxa)
• FDA approved indications:
- Nonvalvular Afib*
- VTE prophylaxis following surgery
- Treat and prevent DVT and/or PE
• Direct thrombin inhibitor
• 75-150mg BID [Based on CrCl]
• Time to peak effect: 2hr
• Metabolism/Elimination
- Half life:12-17hr
- 80% Renal
- 20% Fecal
• Recommended coagulation assay: Dilute TT, anti-factor II
• Reversal: Dialysis, activated charcoal within 1-2hrs of
ingestion
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Rivaroxaban (Xarelto)
• FDA approved in:
- Nonvalvular Afib*
- VTE prophylaxis following surgery
- Treat and prevent DVT and/or PE
• Direct Factor Xa Inhibitor
• 10-20mg Daily
• Time to peak effect: 3hr
• Metabolism: Hepatic—33% to inactive metabolites
• Elimination
- Half life: 5.7-9.2hr
- 33% Renal
- 33% Fecal/Biliary
• Recommended coagulation assay: PT, Anti-Xa
• Reversal: Activated charcoal within 8hr of ingestion; FFP;
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PCC; Factor IV; Recombinant factor VIIa
Ticagrelor (Brilinta)
•
•
•
•
•
•
FDA approved to reduce CV death and MI in ACS
P2Y12 Receptor antagonist
90mg BID maintenance dose
Time to peak effect: 2-4hr
Metabolism: CYP3A4
Elimination:
- Half life: 7hrs; 8.5 hrs for active metabolites
- Primarily Hepatic
• Recommended coagulation
assay: PLT mapping
Reversal: PLTs
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Apixaban (Eliquis)
• FDA approved for:
- Nonvalvular AFib
• Factor Xa Inhibitor
• 5mg BID
• Time to peak effect: 1-3hr
• Metabolism/Elimination:
• Half life: 8-15hr
• 25% Renal Elimination
• 75% Fecal Metabolism and Elimination
• Recommended coagulation assay: Anti-Xa, Dilute PT
• Reversal: Activated charcoal within 3hrs, PLTs
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What’s Next?
Edoxaban (Savaysa)
2 FDA approved (2015) indications:
1. Reducing the risk of stroke in patients who have
NONvalvular atrial fibrillation
2. Treating DVT and PE in patients who have already been
receiving an anticoagulant by injection or by infusion for
5 to 10days
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Suggested Discontinuation Prior to
“High Risk Blood” Loss Surgery
 Prasugrel (Effient®)
 7 days
 Dabigatran (Pradaxa®)
 24-48hrs
 Rivaroxaban (Xarelto®)
 24 hours
 Ticagrelor (Brilinta®)
 5 days
 Apixaban (Eliquis®)
 48 hours
*Per prescribing guidelines set forth by drug manufacturers, ind
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http://www.apsf.org/newsletters/html/2012/spring/pdf/anticoagulant%20table.pdf
apsf Newsletter Spring-Summer 2012
References:
1. Brazzel C. Thromboelastography-guided transfusion therapy in the trauma patient. AANA Journal. 2013;81(2):127132.
2. Johansson PI, Stensballe J, Ostroski SR. Current management of massive hemorrhage in trauma. Scand J Trauma
Resusc Emerg Med. 2012;20(1):47.
3. Spahn S, Bouillon B, Cerny V, et al. Management of bleeding and coagulopathy following major trauma: an
updated European guideline. Crit Care. 2013;17(2):1-45.
4. Johansson PI, Stissing T, Bochsen L, Ostrowski SR. Thromboelastography and tromboelastometry in assessing
coagulopathy in trauma. Scand J Trauma Resusc Emerg Med. 2009;17(45):1-8.
5. Johansson PI, Sorensen AM, Perner A, et al. Disseminated intravascular coagulation or acute coagulopathy of
trauma shock early after trauma? An observational study. Crit Care. 2011;15(6):R272.
6. Plotkin AJ, Wade CE, Jenkins DH, et al. A reduction in clot formation rate and strength assessed by
thrombelastography is indicative of transfusion requirements in patients with penetrating injuries. J Trauma.
2008;64:S64.
7. Benzon HT, Avarm MJ, Green D, Bonow RO. New oral anticoagulants and regional anaesthesia. BJA. 2013; i96i113.
8. New Zealand Med Data Sheets
9. APSF
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