Disseminated Intravascular Coagulation (DIC)

Question 1

Definition of DIC

Answer 1

Is an acquired syndrome that is characterised by the activation of coagulation pathways, resulting in the formation of intravascular thrombi and the DEPLETION of platelets and coagulation factors
• Thrombi can lead to vascular obstruction/ischaemia
• Also risk of bleeding

Question 2

Aetiology of DIC

Answer 2

• Disease states that can trigger systematic activation of coagulation, and may lead to DIC, are:
◦ Sepsis/severe infection
◦ Major trauma or burns
◦ Some malignancies (acute myelocytic leukaemia)
◦ Obstetric disorders
◦ Severe organ destruction or failure
◦ Toxic/immunological reactions: Blood transfusion

• DIC may be acute or chronic
• Acute: MORE COMMON with rapid onset underlying conditions (e.g major trauma, sepsis and massive blood transfusion)

					• Chronic: Associate with less acute disorders such as malignancies

Question 3

Pathophysiology of DIC

Answer 3

• Is a consumption coagulopathy
• 2 important hallmarks of DIC are:
◦ Continuous generation of intravascular fibrin (due to increase in thrombin production) AND
◦ Consumption/depletion of procoagulants and platelets

• With the increased clotting (widespread clot formation), there is also a decrease in fibrinolysis
• This can block blood vessels and cause ischaemia and then organ failure

• With the depletion of platelets and coagulation factors, other areas of the body may start to bleed with the slightest amount of injury

Question 4

History and examination of DIC

Answer 4

• Presence of underlying disease
• Fever
• Evidence of shock: oligoruia, hypotension, tachycardia
• Purpurin fulminans, gangrene or a real cyanosis
• Delirium or coma: can be signs of microvascular/macrovascular thrombosis
• Petechia, ecchymosis, oozing, haematuria: Generalised bleeding

Question 5

Investigations for DIC

Answer 5

• Platelet count: DECREASED due to excessive consumption
• Prothrombin time (PT): often PROLONGED
• D-Dimer: ELEVATED due to large amount of fibrin degradation products
• Fibrinogen: Decreased due to excessive consumption

Question 6

Treatment for DIC

Answer 6

Low bleeding risk:
1) Treat underlying disorder: Aggressive treatment of underlying disorder. Risk assessment for DIC to measure bleeding risk. Daily scoring needed

High bleeding risk or active bleeding:
1) Treat underlying disorder
+ Platelets AND coagulation factors and coagulation inhibitors:
◦ A platelet transfusion should be considered with bad thrombocytopenia or if low platelets and active bleeding
◦ FFP is preferred for replacement of coagulation factors and coagulation inhibitors

Question 7

Complications and prognosis of DIC

Answer 7

• Acute renal failure: can lead to this and multi organ failure (due to widespread intravascular thrombosis, leading to organ ischaemia and failure)
• Life threatening haemorrhage: late complication due to depletion of coagulation factors
• Cardiac tamponade, haemothroax, intracerebral haematoma
• Gangrene and loss of digits: due to ischaemia

Mortality can be high