Disseminated intravascular coagulation
PYQ
- Diagrammatically outline the Normal Coagulation Cascade (DNB 2009/1)4
PYQ
- DIC (DNB 1996/2)15
- Discuss the pathogenesis of disseminated intravascular coagulation (DIC) and relate it to the laboratory abnormalities observed in this entity (DNB 2008/1)10
- Outline diagnosis and management of disseminated Intravascular Coagulation (DIC) (DNB 2009/1)6
- Disseminated intravascular coagulation : a) Etiology b) Diagnosis c) Treatment (DCH 2024/2)3+3+4
- DIC is a complex, acquired syndrome resulting from systemic activation of coagulation resulting in
- microvascular thrombi
- consumption of coagulation factors
Etiology
- always a secondary process
- unregulated thrombin generation
- cause multiorgan dysfunction
- consumption coagulopathy
- factors 5, 8, prothrombin and fibrinogen are consumed faster than they are produced
- bleeding and hemorrhage
- endothelial damage precipitate and amplify this process
Lab features
| Laboratory Test | Abnormality in DIC | Pathogenesis |
|---|---|---|
| Platelet count | Decreased (thrombocytopenia) | Platelet consumption in widespread clot formation |
| PT / aPTT | Prolonged | Consumption of clotting factors, especially V and VIII |
| Fibrinogen | Low (may be normal/increased early, declining is suspicious) | Consumption during ongoing thrombin-mediated clot formation; acute-phase reactant initially elevated |
| D-dimer / FDPs | Elevated | Increased fibrinolysis of widespread fibrin clots |
| Factors V and VIII | Decreased | Consumption, not synthesized to keep up with losses |
| Peripheral Blood Smear | Schistocytes, helmet cells | Microangiopathic destruction of red blood cells in microthrombi |
| LDH, Bilirubin | Elevated | Reflects tissue ischemia and hemolysis of RBCs in microvasculature |
Clinical features
Bleeding Manifestations
- Skin/Mucosal Bleeding: Petechiae, purpura, ecchymoses.
- Oozing from Venipuncture or Surgical Sites
- Hematuria (blood in urine)
- Gastrointestinal Bleeding
- Intracranial Hemorrhage
- Mucosal Bleeds: gums, nose
Thrombotic Manifestations
- Microvascular Thrombosis: May result in organ ischemia and dysfunction.
- Signs of Organ Failure:
- Acute kidney injury (renal failure)
- Pulmonary dysfunction (dyspnea, hypoxia, ARDS)
- Hepatic dysfunction (elevated liver enzymes)
- Neurological dysfunction (confusion, coma)
- Limb Ischemia or digital gangrene (in severe cases)
- Shock (from bleeding or organ failure)
Management
- Treat the Underlying Cause
- sepsis (with antibiotics),
- trauma (surgical intervention),
- malignancy (oncologic therapy),
- removal of causative toxins.
- Blood Product Replacement:
- Platelets for severe thrombocytopenia or active bleeding.
- Fresh-frozen plasma (FFP): To replenish coagulation factors if bleeding and PT/aPTT are prolonged.
- Cryoprecipitate: For hypofibrinogenemia (typically <1g/L).
- Heparin (anticoagulation): Considered when thrombosis is dominant and bleeding risk is low, such as in chronic DIC with significant organ dysfunction due to microvascular thrombosis.
- Recombinant factor VIIa or antifibrinolytics: Generally reserved for special indications or severe, refractory bleeding. Routine use is not recommended.
- Avoid unnecessary invasive procedures to minimize bleeding risk.
- Mechanical thromboprophylaxis (compression devices) is recommended for immobilized patients at risk for thrombosis.
- Monitor laboratory parameters (PT, aPTT, fibrinogen, platelets, D-dimer) to guide therapy and assess response.