In an adult with acute coagulopathy (e.g., trauma, massive hemorrhage, liver failure, cardiac surgery, or disseminated intravascular coagulation), how should thromboelastography be used to guide management?

Use of Thromboelastography (TEG) for Coagulopathy Management

Viscoelastic methods (TEG/ROTEM) should be performed alongside standard coagulation tests (PT, APTT, fibrinogen, platelets) to guide hemostatic therapy in acute coagulopathy, as they provide faster results (30-60 minutes time savings), detect coagulopathies missed by conventional tests, and predict massive transfusion needs and mortality better than routine screening. 1

Core Recommendation Framework

When to Use TEG/ROTEM

• Deploy viscoelastic testing immediately in trauma patients with active bleeding, massive hemorrhage, cardiac surgery, or suspected coagulopathy to characterize the specific defect and guide targeted therapy 1

• Use TEG/ROTEM as an adjunct to—not replacement for—conventional coagulation tests (PT, APTT, fibrinogen, platelets), as both provide complementary information 1, 2

• Obtain results within 15 minutes for critical parameters: clot amplitude at 15 minutes (CA15) for ROTEM or similar rapid TEG parameters can guide early transfusion decisions 3

Key Clinical Advantages Over Conventional Tests

• Conventional PT/APTT monitor only 4% of thrombin production (the initiation phase), meaning they can appear completely normal while overall coagulation is severely abnormal 1

• TEG/ROTEM provides 30-60 minute faster turnaround compared to conventional laboratory testing, critical in hemorrhagic emergencies 1

• Viscoelastic testing predicts massive transfusion need, thromboembolic events, and mortality in trauma and surgical patients better than conventional tests 1

Specific Clinical Applications

Trauma and Massive Hemorrhage

• TEG/ROTEM-guided transfusion protocols reduce mortality in trauma patients and decrease unnecessary blood product transfusions 4

• In a before-and-after study of 832 trauma patients, TEG-guided hemostatic resuscitation (early platelets and FFP) showed improved outcomes 1

• TEG/ROTEM is an early predictor of transfusion requirements: abnormal clot strength predicts need for blood products within 24 hours 5

Cardiac Surgery

• In 3,865 cardiovascular surgery patients, combined TEG/ROTEM and portable coagulometry reduced blood product transfusion and thromboembolic events (though mortality was unchanged) 1

Detecting Specific Coagulopathies

• Hyperfibrinolysis detection: TEG/ROTEM is among the few tests that diagnose and quantify fibrinolysis, guiding tranexamic acid use and cryoprecipitate/fibrinogen concentrate administration 2

• Platelet dysfunction: Clot strength measurements establish whether bleeding is due to coagulopathy versus surgical bleeding 2

• Direct thrombin inhibitor effects: Useful for detecting coagulation abnormalities from dabigatran, argatroban, bivalirudin, or hirudin 1

Critical Technical Considerations and Pitfalls

Technique Standardization Required

• Methods vary significantly between investigators, highlighting the need for standardized protocols before implementation 1

• Requires multiple daily calibrations and must be performed by trained personnel 2

• While partial results are available in minutes, complete testing may take as long as conventional tests 2

Important Limitations to Recognize

• TEG cannot distinguish dilutional coagulopathy from thrombocytopenia, potentially leading to unnecessary platelet transfusions, whereas ROTEM can differentiate these and suggest correct treatment (fibrinogen substitution) 1

• Poor sensitivity for antiplatelet drug effects: If platelet dysfunction from antiplatelet medications is suspected, add point-of-care platelet function tests (whole blood impedance aggregometry) 1

• Poor correlation with conventional parameters has been reported in some studies, emphasizing that TEG/ROTEM provides different—not redundant—information 1

Practical Implementation Algorithm

Step 1: Obtain Baseline Tests Simultaneously

• Draw conventional tests (PT, APTT, fibrinogen, platelets) AND initiate TEG/ROTEM immediately upon patient arrival 1, 6

Step 2: Use Rapid TEG/ROTEM Parameters for Early Decisions

• **Clot amplitude at 15 minutes (CA15-EXTEM) <32 mm**: Sensitivity 87%, specificity 100% for PT >1.5× control—transfuse FFP 3
• Clot amplitude at 10 minutes (CA10-FIBTEM) <5 mm: Sensitivity 91%, specificity 85% for fibrinogen <1 g/L—give fibrinogen concentrate or cryoprecipitate 3

Step 3: Identify Specific Defects

• Prolonged clot formation time: Factor deficiency—consider FFP 3
• Reduced clot strength: Fibrinogen or platelet deficiency—use FIBTEM to differentiate 1
• Increased lysis: Hyperfibrinolysis—administer tranexamic acid 2

Step 4: Repeat Testing During Active Resuscitation

• Coagulopathy evolves rapidly; serial measurements guide ongoing therapy 6

Common Pitfalls to Avoid

• Do not delay TEG/ROTEM until conventional tests return abnormal—early coagulopathy may be missed when PT/APTT appear normal 1, 6

• Do not use TEG alone to guide all transfusion decisions—combine with conventional tests and clinical assessment 1, 2

• Do not assume TEG detects all platelet dysfunction—antiplatelet drug effects require additional testing 1

• Do not transfuse platelets based solely on TEG without considering ROTEM or fibrinogen levels—TEG may misidentify dilutional coagulopathy as thrombocytopenia 1