basic clinician training module 5
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Basic Clinician Training Module 5. Hypercoagulable states. Introduction. A prothrombotic or hypercoagulable state can be the result of: Hyperactive platelet function and/or Hyperactive coagulation cascade function - PowerPoint PPT PresentationTRANSCRIPT
Basic Clinician TrainingModule 5
Hypercoagulable states
Introduction
• A prothrombotic or hypercoagulable state can be the result of: Hyperactive platelet function and/or Hyperactive coagulation cascade
function
• Proper assessment of the factor(s) contributing to a hypercoagulable state is necessary to determine proper pharmacological intervention to prevent the development of a thrombotic event.
Importance of assessing the hypercoagulable state
Percentage of Patients with a Thrombotic ComplicationBy Quartiles of MA Value
McGrath DJ et al.Anesth Analg 96:SCA1-141, 2003
0
5
10
15
20
25
30
35
16-62(n=47)
62.5-66.5(n=60)
67-71(n=56)
71.5-94.5(n=56)
MA range
% w
ith T
hrom
botic
com
plic
atio
n
Insert graph from Sinai study
Assessing hypercoagulability with the TEG
• TEG analysis can demonstrate hypercoagulable as well as hypocoagulable states
• TEG analysis can differentiate between platelet hypercoagulability and enzymatic hypercoagulability.
Hypercoagulable statesPlatelet vs. enzymatic
• Hyperactive platelet function is characterized by rapid clot development and abnormally high clot strength.
• Hyper enzymatic pathway activity is characterized by rapid fibrin formation with subsequent clot formation.
Platelet hypercoagulability
• Characterized by rapid clot development with higher than normal clot strength due to hyperactive platelet function.
• Probable causes: Diminished endogenous platelet inhibitory
mechanisms High platelet numbers Abnormal generation of platelet activators Inflammatory mediators
Platelet hypercoagulabilityCommon conditions
• Antithrombin III deficiency• Thrombomodulin-Protein C dysfunction or
APC resistance• Diminished nitric oxide synthesis/release• Dysplasminogenemia• High plasminogen activator inhibitor• Hyperhomocysteinemia• Malignancy• DIC
Platelet hypercoagulabilityAs shown by TEG
Patient status: high risk for thrombotic event
Probable cause: Rapid clot formation and strong clot developmentCommon treatment: Platelet inhibitor
Platelet hypercoagulabilityTreatment considerations• Step 1: Identify and quantify prothrombotic
state • Step 2: Determine therapeutic response of
anti-platelet therapies WHY?: Patient resistance to aspirin and
clopidogrel has been documented in the literature
HOW?: TEG analysis combined with PlateletMapping assay (Module 6).
• Assesses platelet inhibition against total platelet function
• Provides personalized treatment regimen
Platelet hypercoagulabilityCommon therapy algorithm
Enzymatic hypercoagulability
• Characterized by rapid fibrin generation with subsequent clot formation
• Probable cause(s): Loss of antithrombotic protective
mechanisms• APC resistance (Factor V Leiden)• ATIII deficiency
• Dysfibrinogenemia
Enzymatic hypercoagulabilityAs shown by TEG analysis
Patient status: high risk for thrombotic event
Probable cause: Rapid thrombin generation and subsequent clot formationCommon treatment: Anticoagulation
• Treatment ultimately depends on clinical situation
• Goal is to prevent clot formation Common inpatient treatment: heparin,
LMWH, APC (activate protein C) Common outpatient treatment: LMWH or
Coumadin to maintain INR > 2.0
• If clots have already formed - may require fibrinolytic agent before anticoagulation
Enzymatic hypercoagulabilitySpecial considerations
• Heart assist device• Lupus anticoagulant• Cancer• Orthopedic surgery• Pregnancy• Trauma• Burns• Sepsis
Platelet & enzymatic hypercoagulabilityCommon conditions
Platelet & enzymatic hypercoagulabilityAs shown by TEG analysis
Patient status: high risk for thrombotic event
Probable cause(s): • Rapid thrombin generation • Excessive platelet functionCommon treatment(s): • Anticoagulation and/or• Platelet inhibitor
Interpretation Exercises
Prothrombotic states
Exercise 1
Using the TEG Decision Tree, what is your interpretation of this tracing?(select all that apply)a. Platelet hypercoagulabilityb. Enzymatic hypercoagulabilityc. Platelet and enzymatic hypercoagulabilityd. Secondary fibrinolysis
What would be an appropriate treatment, if any for this patient?
Answer
Next
Exercise 2
Using the TEG Decision Tree, what is your interpretation of this tracing?(select all that apply)a. Platelet hypercoagulabilityb. Enzymatic hypercoagulabilityc. Platelet and enzymatic hypercoagulabilityd. Secondary fibrinolysis
What would be an appropriate treatment, if any for this patient?
Answer
Next
Exercise 3: Off-pump CABG patient
The above are tracings from a patient who has undergone an off-pumpCABG. What is this patient’s current hemostatic state (black tracing)?a. Platelet hypercoagulabilityb. Enzymatic hypercoagulabilityc. Platelet and enzymatic hypercoagulabilityd. Secondary fibrinolysis
What would be an appropriate treatment, if any for this patient?
Green: Pre-opBlack: Before protamine
Kaolin with heparinase
Answer
Next
Exercise 4
Answer
Next
Using the TEG Decision Tree, what is your interpretation of this tracing?(select all that apply)a. Platelet hypercoagulabilityb. Enzymatic hypercoagulabilityc. Platelet and enzymatic hypercoagulabilityd. Secondary fibrinolysis
What would be an appropriate treatment, if any for this patient?
Exercise 5
Using the TEG Decision Tree, what is your interpretation of this tracing?(select all that apply)a. Platelet hypercoagulabilityb. Enzymatic hypercoagulabilityc. Platelet and enzymatic hypercoagulabilityd. Secondary fibrinolysis
What would be an appropriate treatment, if any, for this patient?
Answer
Next
Exercise 6
Answer
Next
Using the TEG Decision Tree, what is your interpretation of this tracing?(select all that apply)a. Platelet hypercoagulabilityb. Enzymatic hypercoagulabilityc. Platelet and enzymatic hypercoagulabilityd. Secondary fibrinolysis
If this was a tracing from a pre-bypass cardiac surgical patient,what type of antifibrinolytic treatment would you consider?
Exercise 1
Using the TEG Decision Tree, what is your interpretation of this tracing?(select all that apply)a. Platelet hypercoagulabilityb. Enzymatic hypercoagulabilityc. Platelet and enzymatic hypercoagulabilityd. Secondary fibrinolysis
What would be an appropriate treatment, if any for this patient?Consider an anti-platelet agent.
Back
Next
Exercise 2
Using the TEG Decision Tree, what is your interpretation of this tracing?(select all that apply)a. Platelet hypercoagulabilityb. Enzymatic hypercoagulabilityc. Platelet and enzymatic hypercoagulabilityd. Secondary fibrinolysis
What would be an appropriate treatment, if any for this patient?Consider treatment with both an anticoagulant and anti-plateletagent.
Back
Next
Exercise 3: Off-pump CABG patient
The above are tracings from a patient who has undergone an off-pumpCABG. What is this patient’s current hemostatic state (black tracing)?a. Platelet hypercoagulabilityb. Enzymatic hypercoagulabilityc. Platelet and enzymatic hypercoagulabilityd. Secondary fibrinolysis
What would be an appropriate treatment, if any for this patient?Although the R value is within normal range, the pre-op value was lower than normal. Consider half the normal protamine dose plus an anti-platelet agent.
Green: Pre-opBlack: Before protamine
Kaolin with heparinase
Back
Next
Exercise 4
Back
Next
Using the TEG Decision Tree, what is your interpretation of this tracing?(select all that apply)a. Platelet hypercoagulabilityb. Enzymatic hypercoagulabilityc. Platelet and enzymatic hypercoagulabilityd. Secondary fibrinolysis
What would be an appropriate treatment, if any for this patient?Consider treatment with an anticoagulant.
Exercise 5
Using the TEG Decision Tree, what is your interpretation of this tracing?(select all that apply)a. Platelet hypercoagulabilityb. Enzymatic hypercoagulabilityc. Platelet and enzymatic hypercoagulabilityd. Secondary fibrinolysis
What would be an appropriate treatment, if any, for this patient?Consider an anticoagulant plus an anti-platelet agent.
Back
Next
Exercise 6
Back
Next
Using the TEG Decision Tree, what is your interpretation of this tracing?(select all that apply)a. Platelet hypercoagulabilityb. Enzymatic hypercoagulabilityc. Platelet and enzymatic hypercoagulabilityd. Secondary fibrinolysis
If this was a tracing from a pre-bypass cardiac surgical patient,what type of antifibrinolytic treatment would you consider? Since the patientis hypercoagulable, treatment with an antifibrinolytic agent may be contra-indicated at this phase in the surgery. Repeat a TEG during CPB to determineif fibrinolysis has developed and treat accordingly.
End of Module 5