Disseminated Intravascular Coagulation Flashcards
What is DIC?
Activation of coagulation system
- leads to inappropriate hypercoagulation and secondary hemorrhage
- develops secondary to a variety of primary illnesses
- may lead to multiple sites of hemorrhage and thrombosis
- Thromboses potentially more damaging than hemorrhage
What can DIC occur secondary to?
- Sepsis and endotoxemia
- acute GI disease
- localized infections
- immune-mediated disease
- Neoplasia
The activity of what is usually lowered in equine DIC?
antithrombin III activity
What happens during SIRS and DIC?
- systemic inflammation SIRS
- activation of coagulation and vascular endothelial disruption
- pathological expression of tissue factor (TF)
- induce production of thrombin
- ATIII and protein C: coagulation inhibitors dysregulation
- subsequent platelet and coag. protein depletion induce severe consumption coagulopathy.
What are the clinical pathological abnormalities of DIC?
- procoagulant activation
- fibrinolysis activation
- inhibitor consumption
- organ damage
What are the clinical signs of DIC?
no obvious signs until terminal event
What are the clinical signs of DIC during SIRS?
- petechiation and GI mucosal line
- prolonged bleeding following surgical procedure
- gastrointestinal tract
- spontaneous bleeding
- rapid death without bleeding
- hemorrhagic diathesis mainly in severe cases (epistaxis and hematuria)
- Hemorrhagic tendency after venipuncture (most common after jugular thrombophlebitis
- Thromboembolism (lung, kidney, liver)
How can DIC be diagnosed?
- platelet count
- Thrombocytopenia: <100,000/ul
- platelet consumption mild to moderate thrombocytopenia
- platelet activation
- Coagulation factor consumption
- prolonged prothrombin time (PT)
- Activated partial thromboplastin
- possible hyperfibrinogenemia
- Coagulation factor inhibitor consumption
- decr plasma AT or protein C
- Incr D-dimers
What is a sensitive test for the diagnosis of DIC?
Antithrombin III (decreased levels in plasma indicate DIC)
True or False? Protein C is specific for DIC.
False. It is an acute phase reaction protein
What does an increase in D-dimers indicate?
the amount of fibrin formation within vasculature
- Elisa test D-dimers appear to have highest sensitivity
What tests are used to Diagnose DIC? How many have to be positive for DIC to be an acceptable diagnosis?
3 or more tests to diagnose
- Platelet count
- prolonged prothrombin time (PT)
- Activated partial thromboplastin (aPTT)
- Fibrinogen concentration
- Antithrombin activity
- D-dimer concentration
How can Coagulation factor activation be detected?
an increase in thrombin-antithrombin complex (TAT)
- only in research
How is DIC treated?
- control underlying disease
- Anti-microbial therapy
- Hydroxyethyl stratch solution (hetastarch) in horses w/ endotoxemia (restores endothelial permeability, reduces platelet activation
- Yunnan Baiyao (traditional Chinese herbal remedy)
How is the hypercoagulable phase fo DIC treated?
- unfractioned heparin to decrease hypercoagulation
- Low molecular weight heparin (anticoagulant and antiplatelet aggregation properties. more effective than UFH)
- Dalteparine 50IU/kg SQ SID
- Enoxaparin 0.5mg/kg SQ SID
