What is Disseminated Intravascular Coagulation (DIC)?

From the Guidelines

Disseminated Intravascular Coagulation (DIC) should be managed by addressing the underlying cause and providing supportive care, including the use of heparin in specific cases with predominant clotting and minimal bleeding, as recommended by the guidance from the SSC of the ISTH 1.

Overview of DIC

DIC is a serious condition characterized by the abnormal activation of the blood's clotting system throughout the body, leading to both widespread clotting and severe bleeding. It often occurs as a complication of severe illnesses such as sepsis, trauma, cancer, or obstetric emergencies. The presentation of DIC can include bleeding from multiple sites, organ dysfunction, and specific laboratory findings like low platelet counts, prolonged clotting times, elevated D-dimer levels, and decreased fibrinogen levels.

Management of DIC

The primary focus of DIC management is to address the underlying cause of the condition. This can involve treating infections with appropriate antibiotics, managing trauma, or addressing obstetric complications. Supportive care is also crucial and may include the replacement of blood products. For instance, platelet transfusions may be necessary for patients with platelet counts below 50,000/μL, fresh frozen plasma may be administered at a dose of 10-15 mL/kg, and cryoprecipitate may be given for fibrinogen levels below 100 mg/dL.

Role of Heparin in DIC Management

The use of heparin in DIC management is a topic of debate but can be considered in specific cases. According to the guidance from the SSC of the ISTH 1, heparin, either unfractionated (UFH) or low-molecular-weight (LMWH), can be used to inhibit excess thrombin generation, which is a key feature of DIC. However, the decision to use heparin should be made cautiously, particularly in patients with a high risk of bleeding or those with solid cancers, where heparin should be considered as prophylactic therapy in the absence of contraindications such as a low platelet count (less than 20 x 10^9/L) or active bleeding 1.

Choice of Heparin and Monitoring

The choice between UFH and LMWH depends on the patient's risk of bleeding and renal function. UFH is preferred in patients with a high risk of bleeding and renal failure due to its easier reversibility, while LMWH is recommended for all other cases 1. Monitoring the antithrombotic capacity of UFH using PTT may be problematic in DIC due to prolonged baseline PTT values, and heparin anti-FXa activity assays can be used as an alternative monitoring method.

Key Considerations

• Addressing the underlying cause is paramount in the management of DIC.
• Supportive care, including blood product replacement, is critical.
• Heparin therapy may be considered in specific cases, with careful selection of patients and monitoring.
• The choice of heparin (UFH vs. LMWH) should be based on the patient's risk profile and renal function.
• Monitoring of heparin therapy is essential to balance the risk of thrombosis and bleeding.

From the Research

Definition and Pathophysiology of DIC

• Disseminated intravascular coagulation (DIC) is a complex and serious condition characterized by widespread activation of the coagulation cascade, resulting in both thrombosis and bleeding 2.
• The main pathophysiological mechanisms of DIC are inflammatory cytokine-initiated activation of tissue factor-dependent coagulation, insufficient control of anticoagulant pathways, and plasminogen activator inhibitor 1-mediated suppression of fibrinolysis 3.
• DIC is an acquired syndrome characterized by widespread intravascular activation of coagulation that can be caused by infectious insults (such as sepsis) and non-infectious insults (such as trauma) 3.

Causes and Triggers of DIC

• The primary causes of DIC include sepsis, trauma, malignancies, and obstetric complications, which trigger an overactive coagulation response 2.
• Other conditions associated with acute DIC include septic shock, exsanguinating trauma, burns, or acute promyelocytic leukemia 4.
• DIC can be provoked by several underlying disorders, such as sepsis, cancer, trauma, and pregnancy complicated with eclampsia or other calamities 5.

Diagnosis of DIC

• The diagnosis of DIC should encompass both clinical and laboratory information, using the International Society for Thrombosis and Haemostasis (ISTH) DIC scoring system 6.
• The ISTH DIC scoring system provides an objective measurement of DIC and correlates with key clinical observations and outcomes 6.
• Laboratory tests, such as platelet count, prothrombin time (PT), and activated partial thromboplastin time (aPTT), are used to diagnose and monitor DIC 6.

Treatment and Management of DIC

• The cornerstone of the treatment of DIC is the treatment of the underlying condition 2, 6.
• Treatment strategies for DIC aim to control activation of blood coagulation and bleeding risk, and may involve supportive care, anticoagulation therapy, and other supportive measures 2, 5.
• Transfusion of platelets or plasma (components) in patients with DIC should not primarily be based on laboratory results and should in general be reserved for patients who present with bleeding 6.
• In patients with DIC and bleeding or at high risk of bleeding, administration of fresh frozen plasma (FFP) or factor concentrates may be useful 6.