Coagulopathy Overview

Key Concepts

• Coagulopathy is a condition involving abnormal bleeding due to a malfunction in the coagulation cascade.
• Types of bleeding:
  • Superficial Bleeding: Indicative of platelet disorders (e.g., thrombocytopenia, qualitative platelet dysfunction). Examples include petechiae, gingival bleeding, menorrhagia, prolonged bleeding from minor cuts.
  • Deep Bleeding: More associated with coagulopathies, characterized by ecchymosis, hematomas, hemarthrosis, and prolonged bleeding after surgery.

Coagulation Pathways

• Intrinsic Pathway: Involves factors 12, 11, 9, 8. Key for secondary hemostasis.
• Extrinsic Pathway: Primarily involves factor 7. Triggered by tissue injury and release of tissue factor.
• Common Pathway: Convergence of intrinsic and extrinsic pathways leading to fibrin formation.

Diagnosing Coagulopathy

• Intrinsically Elevated PTT: Suggests issues with factors 12, 11, 9, or 8. Conditions include Hemophilia A (factor 8 deficiency), Hemophilia B (factor 9 deficiency), severe von Willebrand disease, anticoagulant use like heparin, acquired factor inhibitors.
• Extrinsically Elevated PT/INR: Often indicates factor 7 deficiency or early vitamin K deficiency.
• Combined Pathway Defects: Seen in DIC, cirrhosis. Results in prolonged PT/PTT, low fibrinogen, thrombocytopenia, elevated D-Dimer in DIC.

Specific Conditions

• Hemophilia: X-linked recessive, mostly affects males.
  • Hemophilia A: Factor 8 deficiency.
  • Hemophilia B: Factor 9 deficiency.
• Von Willebrand Disease (VWD): Affects platelet function and factor 8 stability.
  • Types 1, 2 (dysfunctional VWF), and 3 (severe deficiency).
• DIC (Disseminated Intravascular Coagulation): Widespread clotting leading to consumption of clotting factors. Triggered by sepsis, trauma, malignancy, and obstetric complications.
• Cirrhosis: Liver inability to produce clotting factors.
• Vitamin K Deficiency: Affects synthesis of factors 2, 7, 9, 10. Common in warfarin use, malabsorption, prolonged antibiotics.

Laboratory Tests

• PTT (Partial Thromboplastin Time): Prolonged in intrinsic pathway defects.
• PT/INR (Prothrombin Time/International Normalized Ratio): Prolonged in extrinsic pathway defects.
• Mixing Studies: Helps differentiate between factor deficiency and inhibitor presence.
• D-Dimer: Elevated in DIC due to clot burden.
• Peripheral Smear: Presence of schistocytes suggest hemolytic process.

Treatment Strategies

• Treat underlying conditions where possible.
• Von Willebrand Disease:
  • DDAVP for mild bleeding.
  • VWF concentrate for severe cases.
• Hemophilia:
  • Factor concentrates: Factor 8 for Hemophilia A, Factor 9 for Hemophilia B.
  • Emicizumab for resistant Hemophilia A.
• Heparin-Induced Coagulopathy:
  • Protamine sulfate to reverse excess heparin.
• Vitamin K Deficiency:
  • PCC (Prothrombin Complex Concentrate) + IV Vitamin K in acute warfarin-associated bleeding.
  • Oral Vitamin K for asymptomatic elevated INR.
• For DIC:
  • Platelet transfusions, FFP (Fresh Frozen Plasma), cryoprecipitate for bleeding management.
• For Cirrhosis:
  • Supportive care with platelet transfusion, FFP, cryoprecipitate as needed.

These notes provide a comprehensive overview of the mechanisms, diagnosis, and management strategies associated with coagulopathy.