How should disseminated intravascular coagulation be diagnosed and managed?

Diagnosis and Management of Disseminated Intravascular Coagulation

Diagnostic Approach

Use the ISTH overt-DIC scoring system (≥5 points) to confirm the diagnosis in any patient with an appropriate clinical trigger and laboratory evidence of consumptive coagulopathy. 1

Clinical Prerequisites for Diagnosis

DIC diagnosis requires both laboratory abnormalities and an appropriate underlying condition: 1

• Sepsis (most common trigger) 1
• Trauma
• Malignancy
• Obstetric complications (eclampsia, placental abruption, amniotic fluid embolism)
• Major surgery or burns 2

ISTH Overt-DIC Scoring System

Calculate points from four laboratory parameters: 1

Platelet count:

• ≥100 × 10⁹/L = 0 points
• 50–100 × 10⁹/L = 1 point
• <50 × 10⁹/L = 2 points 1

Fibrin markers (D-dimer/FDP):

• No increase = 0 points
• Moderate increase = 2 points
• Strong increase = 3 points 1

PT prolongation:

• <3 seconds = 0 points
• 3–6 seconds = 1 point

• 6 seconds = 2 points 1

Fibrinogen level:

• ≥1.0 g/L = 0 points
• <1.0 g/L = 1 point 1

A score ≥5 confirms overt DIC. 1

Early Detection in Sepsis

For septic patients, use a two-step approach: 1

1. Screen with Sepsis-Induced Coagulopathy (SIC) criteria when platelets <150 × 10⁹/L (incorporates platelet count, PT-INR, and SOFA score ≥4) 1
2. Confirm overt DIC using ISTH criteria if SIC is positive 1

Mortality in patients meeting SIC criteria is ≥30%, and virtually all who develop overt DIC previously met SIC criteria. 1

Critical Laboratory Findings

• Platelet count: A ≥30% drop is diagnostic of subclinical DIC even when absolute values remain normal 1
• PT/aPTT: May be prolonged, though normal values do not exclude DIC 1
• Fibrinogen: Typically decreased due to consumption, but may be normal or elevated early in sepsis due to acute-phase response 1
• D-dimer: Elevated, indicating fibrinolysis; highly sensitive for DIC 1
• Antithrombin: Decreased due to consumption; helps distinguish DIC from chronic liver disease 1

Dynamic Monitoring is Essential

Trend analysis over hours to days is more diagnostically important than single absolute values. 1 Adjust monitoring frequency based on clinical severity:

• Daily: Acute severe DIC with active bleeding or rapid deterioration 1, 3
• Every 2-3 days: Stable ICU patients with diagnosed DIC 1
• Weekly: Hospitalized patients with chronic DIC (e.g., cancer-associated) 1
• Monthly: Outpatients with stable subclinical DIC 1

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Management Algorithm

Step 1: Treat the Underlying Trigger (Primary Goal)

DIC will not resolve without addressing the root cause. 3, 4 Immediate interventions include:

• Sepsis: Source control and appropriate antibiotics 3
• Malignancy: Early chemotherapy (especially acute promyelocytic leukemia, which achieves rapid DIC resolution) 3, 4
• Trauma: Surgical intervention 3
• Obstetric complications: Delivery and management of eclampsia 3

Step 2: Identify the Clinical Phenotype

DIC presents in three distinct forms that guide management: 3

Procoagulant DIC (thrombosis-predominant):

• Common in pancreatic cancer and adenocarcinomas 1
• Presents with arterial ischemia, venous thromboembolism, or microvascular thrombosis 1
• May manifest as symmetrical peripheral gangrene with acral limb loss 1

Hyperfibrinolytic DIC (bleeding-predominant):

• Typical of acute promyelocytic leukemia and metastatic prostate cancer 1
• Presents with widespread bleeding from multiple sites 1

Subclinical DIC:

• Laboratory abnormalities without overt clinical manifestations 3
• Diagnosed by ≥30% platelet drop, elevated D-dimer, and mild coagulation factor consumption 1

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Supportive Hemostatic Management

For Bleeding-Predominant DIC

Platelet transfusion:

• Maintain platelets >50 × 10⁹/L in actively bleeding patients 3, 4
• For high-risk patients without active hemorrhage: transfuse if <30 × 10⁹/L in acute promyelocytic leukemia or <20 × 10⁹/L in other malignancies 4
• Before major invasive procedures: maintain >50 × 10⁹/L 4

Fresh frozen plasma (FFP):

• Administer 15–30 mL/kg to bleeding patients with prolonged PT/aPTT 3, 4
• Dose adjustments should be guided by clinical response, not isolated laboratory values 4
• If volume overload is a concern, consider prothrombin complex concentrates (recognizing they provide only selected factors) 4

Fibrinogen replacement:

• If fibrinogen remains <1.5 g/L despite FFP, administer two pools of cryoprecipitate or fibrinogen concentrate 3, 4
• Cryoprecipitate should not be given for isolated laboratory abnormalities without active bleeding 4

Critical caveat: Transfused platelets and clotting factors have a very short lifespan in DIC due to ongoing consumption, often requiring repeated dosing. 3, 4 Do not transfuse solely based on laboratory abnormalities; clinical bleeding or procedural risk must drive decisions. 4

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Anticoagulation Decision-Making

For Thrombosis-Predominant DIC

Initiate therapeutic-dose heparin (preferably low-molecular-weight heparin) for: 3, 4

• Arterial or venous thromboembolism
• Severe purpura fulminans with acral ischemia
• Vascular skin infarction
• Cancer-associated DIC with thrombotic events

Do not withhold anticoagulation solely because PT/aPTT are prolonged. 4 DIC reflects a rebalanced hemostatic state with simultaneous loss of pro- and anticoagulant factors; abnormal coagulation screens alone should not preclude anticoagulation in the absence of bleeding. 4

Prophylactic Anticoagulation

In cancer-associated DIC without active bleeding, consider prophylactic heparin unless: 4

• Platelets <20 × 10⁹/L 3, 4
• Active bleeding is present 3

Choice of Heparin

• Unfractionated heparin: Preferred for patients at high bleeding risk with renal impairment due to rapid reversibility 3, 4
• Low-molecular-weight heparin: Preferred in other cases 3, 4

Contraindications

Heparin must be avoided in hyperfibrinolytic DIC, where it can exacerbate bleeding. 3, 4

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Agents to Avoid

Tranexamic acid:

• Should not be used routinely in DIC; may increase thrombotic events 3, 4
• Reserved only for therapy-resistant bleeding with documented hyperfibrinolysis 3, 4

Recombinant factor VIIa:

• Discouraged in DIC; uncertain benefit with definite thrombotic risk 3, 4

Corticosteroids:

• No established benefit; not recommended 4

Antiplatelet agents:

• Not indicated; may increase bleeding risk 4

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Common Pitfalls and How to Avoid Them

1. Do not transfuse based on laboratory values alone. Clinical bleeding or procedural risk must drive transfusion decisions. 4

2. Do not withhold anticoagulation in thrombotic DIC because of prolonged PT/aPTT. The hemostatic balance permits anticoagulation when bleeding is absent. 4

3. Recognize that transfused blood products have reduced survival in active DIC. Repeated administrations are often necessary. 4

4. Do not use prophylactic FFP or cryoprecipitate before low-risk invasive procedures. There is no good evidence supporting this practice. 4

5. Monitor trends, not single values. Dynamic assessment over hours to days is more informative than isolated laboratory results. 1

6. Endothelial injury is an essential component of DIC, yet current diagnostic criteria do not include endothelium-related biomarkers. 5 Antithrombin activity and von Willebrand factor can serve as candidates for assessing endothelial dysfunction when available. 5