Disseminated Intravascular Coagulation (DIC)

Definition

Disseminated Intravascular Coagulation (DIC) is a serious condition that occurs when the body's blood clotting mechanisms become overactive, leading to the formation of clots throughout the small blood vessels. This can cause multiple organ damage and severe bleeding due to the depletion of clotting factors and platelets.

Aetiology

DIC can be triggered by various underlying conditions, including:

Severe infections (e.g., sepsis)
Trauma or surgery
Cancers (e.g., leukaemia, metastatic carcinoma)
Complications of pregnancy (e.g., pre-eclampsia, placental abruption)
Liver disease
Severe allergic reactions

Pathophysiology

In DIC, the normal balance between clot formation and clot breakdown is disrupted. This leads to:

Widespread activation of the coagulation cascade, resulting in the formation of fibrin clots in small blood vessels
Consumption of platelets and clotting factors, leading to bleeding
Activation of fibrinolysis, further contributing to bleeding

Risk Factors

Severe infections (e.g., bacterial sepsis)
Trauma or extensive surgery
Malignancies
Pregnancy complications
Liver disease
Severe allergic reactions

Signs and Symptoms

Common signs and symptoms of DIC include:

Spontaneous bruising or bleeding (e.g., gums, nosebleeds)
Prolonged bleeding from cuts or injections
Multiple small red dots on the skin (petechiae)
Blood in urine or stool
Severe haemorrhage
Organ dysfunction due to microvascular thrombi

Investigations

Full blood count (FBC): To assess for thrombocytopenia.
Prothrombin time (PT) and activated partial thromboplastin time (aPTT): Both are usually prolonged in DIC.
Fibrinogen levels: Typically decreased in DIC.
D-dimer test: Elevated in DIC due to increased fibrin degradation products.
Peripheral blood smear: May show fragmented red blood cells (schistocytes).

Management

Primary Care Management

Immediate referral to a specialist: Patients with suspected DIC should be referred to a haematologist or an appropriate specialist immediately.
Initial stabilisation: Ensure airway, breathing, and circulation (ABCs) are stabilised. Administer intravenous fluids if needed.

Specialist Management

Treatment of underlying cause: Addressing the primary condition (e.g., antibiotics for sepsis, surgery for trauma).
Supportive care: Blood product transfusions (e.g., platelets, fresh frozen plasma) to manage bleeding and replace depleted clotting factors.
Anticoagulation therapy: In certain cases, low-dose heparin may be used to inhibit further clotting.
Monitoring and supportive measures: Regular monitoring of coagulation parameters, organ function, and supportive measures in an intensive care setting.

References

NHS. (2024). Pre-eclampsia - Complications. Retrieved from NHS
North West London Pathology. (2024). Coagulation Screen. Retrieved from NWL Pathology
Gloucestershire Hospitals NHS Foundation Trust. (2024). Disseminated Intravascular Coagulation (DIC). Retrieved from Gloucestershire Hospitals