Diagnostic Criteria and Management of Disseminated Intravascular Coagulation (DIC)
The International Society on Thrombosis and Haemostasis (ISTH) recommends a two-step diagnostic approach for DIC, first screening for sepsis-induced coagulopathy (SIC) in patients with thrombocytopenia, followed by assessment for overt DIC if SIC criteria are met. 1
Diagnostic Criteria
Step 1: Sepsis-Induced Coagulopathy (SIC) Screening
For patients with thrombocytopenia (platelet count <150 × 10^9/L), apply the SIC scoring system:
| Parameter | Score | Criteria |
|---|---|---|
| Platelet count (×10^9/L) | 2 | <100 |
| 1 | ≥100, <150 | |
| PT ratio | 2 | >1.4 |
| 1 | >1.2, ≤1.4 | |
| SOFA score | 2 | ≥2 |
| 1 | 1 |
SIC diagnosis: Total score ≥4 1
Step 2: Overt DIC Criteria
If SIC criteria are met, proceed to evaluate for overt DIC:
| Parameter | Score | Criteria |
|---|---|---|
| Platelet count (×10^9/L) | 2 | <50 |
| 1 | ≥50, <100 | |
| FDP/D-dimer | 3 | Strong increase |
| 2 | Moderate increase | |
| PT | 2 | ≥6 seconds prolonged |
| 1 | ≥3, <6 seconds prolonged | |
| Fibrinogen (g/mL) | 1 | <100 |
Overt DIC diagnosis: Total score ≥5 1
Management Strategies
1. Treatment of Underlying Condition
- The cornerstone of DIC management is treating the underlying cause, particularly sepsis which is the most common trigger 1, 2
- Early and aggressive infection control is essential for sepsis-associated DIC
2. Blood Component Therapy
Platelet transfusion:
- Indicated for patients with active bleeding and platelet count <50 × 10^9/L
- Not recommended prophylactically in non-bleeding patients unless high bleeding risk exists 2
Fresh Frozen Plasma (FFP):
- Administer to bleeding patients with prolonged PT and aPTT
- Should not be given based solely on laboratory results 2
- Consider factor concentrates if fluid overload is a concern
Fibrinogen replacement:
- Use cryoprecipitate or fibrinogen concentrate when levels remain <1 g/L despite FFP 2
3. Anticoagulant Therapy
Heparin:
- Therapeutic doses recommended when thrombosis predominates (arterial/venous thromboembolism, purpura fulminans, vascular skin infarction) 2
- Unfractionated heparin (UFH) preferred in high bleeding risk cases due to short half-life (10 units/kg/h)
- Prophylactic doses recommended in critically ill, non-bleeding DIC patients 2
Antithrombin:
Recombinant thrombomodulin:
Recombinant activated protein C:
- Consider in severe sepsis with DIC (24 μg/kg/h for 4 days)
- Contraindicated in patients with high bleeding risk or platelet counts <30 × 10^9/L 2
4. Antifibrinolytic Therapy
- Generally not recommended in DIC patients 2
- May be considered in cases with primary hyperfibrinolytic state and severe bleeding (tranexamic acid 1g every 8h) 2
Special Considerations
Symmetrical Peripheral Gangrene (SPG)
- A devastating complication of sepsis and DIC causing distal extremity limb loss
- Associated with acute hepatic dysfunction ("shock liver")
- Timely administration of heparin and antithrombin might reduce risk 1
Monitoring
- Serial laboratory monitoring is crucial due to the dynamic nature of DIC 2
- Repeat testing to assess progression and response to therapy
Emerging Biomarkers
- Endothelium-related biomarkers may improve early detection of DIC 1
- Antithrombin activity and von Willebrand factor are potential candidates for assessing endothelial injury 1
Pitfalls to Avoid
- Delaying diagnosis and treatment of the underlying condition
- Transfusing blood products based solely on laboratory results without clinical correlation
- Failing to recognize that DIC exists on a continuum from early SIC to overt DIC
- Not considering the predominant clinical manifestation (bleeding vs. thrombosis) when selecting therapy
- Overlooking hepatic dysfunction which may predispose to complications like SPG
Early recognition using the two-step diagnostic approach and prompt intervention targeting the underlying cause are essential for improving outcomes in DIC.