Disseminated intravascular coagulation
From IDWiki
Background
- Systemic microvascular coagulation leading to organ dysfunction and depletion of clotting factors and platelets
Etiologies
- Sepsis, from gram-negative bacteria, gram-positive bacteria, some viruses, and some parasites (including malaria)
- Trauma, particularly brain trauma
- Organ destruction e.g pancreatitis
- Malignancy
- Solid tumour, especially mucinous tumours (pancreatic, gastric, ovarian) and brain tumours
- Leukaemia, especially promyelocytic leukemia
- Obstetric complications
- Vascular abnormalities
- Large haemangiomata
- Vascular aneurysm
- Severe liver failure
- Toxic and immunological insults
- Snake bite
- Recreational drug use
- Acute hemolytic transfusion reaction from ABO incompatibility
- Transplant rejection
Differential Diagnosis
- Thrombotic microangiopathies, including TTP and HUS
- Severe liver failure
- Heparin-induced thrombocytopenia
- Catastrophic antiphospholipid syndrome
Investigations
- Thrombocytopenia is the most sensitive (Sn 98%)
- D-dimer also sensitive, but not specific
- Elevated INR/PTT (Sn 50-60%), but can be normal
- Low fibrinogen is not very sensitive (Sn 28%), but serial measurement may be helpful
- Blood film may show fragments
ISTH Diagnostic Scoring System
- Only useful in the context of an underlying disorder known to be associated with overt DIC
- Needs PT, platelet count, fibrinogen, and fibrin-related marker (e.g. D-dimer)
Marker | Value | Score |
---|---|---|
Platelet count | >100 <100 <50 |
0 1 2 |
Elevated fibring marker (e.g. D-dimer, fibrin degradation products) | no increase moderate increase strong increase |
0 2 3 |
Prolonged PT | <3 sec >3 sec >6 sec |
0 1 2 |
Fibrinogen level | >1 g/L <1 g/L |
0 1 |
Interpretation
- ≥5 compatible with over DIC: repeat score daily
- <5 suggestive for non-overt DIC: repeat in next 1-2 days
Management
- Treat the underlying cause!
Transfusions
- Only supplement blood products if they are actively bleeding, or to prepare them for an invasive procedure that may cause bleeding
Platelets
- Platelets to target ≥50 if bleeding
- Platelets not needed if not bleeding unless otherwise at risk
- Weak evidence to target 10-20
Plasma and components
- May be indicated in bleeding patients with PT or aPTT >1.5x normal or fibrinogen <1.5 g/L
- FFP 15-30 ml/kg can correct the coagulopathy
- PCC lacks Factor V and may worsen coagulopathy due to trace amounts of active factors
- Fibrinogen 3 g should raise the plasma fibrinogen by about 1 g/L
- Can be given as 4 units FFP, 2 units pooled cryoprecipitate, or 3 g fibrinogen concentrate
Anticoagulation
- In cases of severe thrombosis, including arterial or venous thromboembolism, severe purpura fulminans associated with acral ischemia or vascular skin infarction, consider unfractionated heparin (UFH)
- Target a PTT 1.5-2.5x normal
- Monitor closely for bleeding
- Other patients still need DVT prophylaxis with heparin or LMWH
Further Reading
- Wada H et al. Guidance for diagnosis and treatment of disseminated intravascular coagulation from harmonization of the recommendations from three guidelines. J Thromb Haemost. 2013;11:761–767.