DIC

Question 1

diagnostic value of schistocytes on peripheral smear for DIC diagnosis

Answer 1

this finding is neither sensitive nor specific for DIC

Question 2

Indications for cryo in DIC

Answer 2

critical bleeding AND

fibrinogen level <50 mg/dL

Question 3

Why d-dimer is commonly elevated in metastatic cancer

Answer 3

Systemic activation of hemostasis is common in metastatic cancer, even in the absence of thrombosis. Moreover, it has been implicated in tumor progression, angiogenesis and metastatic spread.

Question 4

how is DIC diagnosed

Answer 4

• Clinical + laboratory diagnosis (labs + inciting factor)

Question 5

How does normal hemostasis work?

Answer 5

Blood clot forms at the site of vessel injury –> clot is resolved to allow tissue repair.

Question 6

WHy is thrombocytopenia associated with DIC?

Answer 6

Microthrombi include platelets

Question 7

Cancers highly associated with DIC

Answer 7

1) acute promyelocytic leukemia (APML)
2) mucinous tumors (eg, pancreatic, gastric, ovarian)
3) brain tumors

Question 8

Thrombotic vs. bleeding risk of DIC

Answer 8

• acute DIC is much more likely to present with bleeding (consumption of fibrinogen and other procoagulant factors and the disruption of normal fibrin formation and platelet function by the large amount of fibrin degradation products)
• chronic DIC (more likely to present with thromboembolic complications because production of procoagulant factors keeps pace with ongoing generation of thrombi).

Question 9

complication of chronic DIC in cancer patients

Answer 9

non-bacterial thrombotic endocarditis (marantic endocarditis, Libman-Sacks endocarditis, verrucous endocarditis)

Question 10

organ dysfunction that can result from DIC

Answer 10

Mostly from vascular damage and hypoperfusion.
(basically everything)
- Acute renal failure
- Hepatic dysfunction
- Acute lung injury (damage to vascular endothelium)
- Neurologic dysfunction
- Adrenal failure

Question 11

what is purpura fulminans?

Answer 11

Rare, life-threatening condition characterized by DIC, with extensive tissue thrombosis and hemorrhagic skin necrosis.

Question 12

Laboratory differences between acute and chronic DIC

Answer 12

• Prolonged PT and PTT and hypofibrinogenemia + thrombocytopenia more common in acute setting (clotting factor consumption)

Question 13

Key principle in treatment of DIC

Answer 13

Treat underlying cause (eliminate the stimulus)

Question 14

why you can’t give TXA to counteract fibrinolysis

Answer 14

It will increase risk of thrombosis

Question 15

Risk of thrombosis with DIC generally speaking

Answer 15

Low, it’s still rare, more common if underlying trigger is infection
*more common in chronic

Question 16

When to expect coagulation abnormalities to resolve after underlying issue is treated

Answer 16

There’s a LAG. DIC does not resolve immediately once the inciting factor is corrected. Resolution generally requires synthesis of coagulation factors, which are produced at different rates; clearance of anticoagulant factors and fibrin degradation products from the circulation, which depend on hepatic function; and production of new platelets from the bone marrow, which may take several days.

Question 17

Rule of thumb for cryo dosing and response in fibrinogen level

Answer 17

Each 10 units will increase fibrinogen by roughly 100

Question 18

pathophysiology of DIC

Answer 18

• abnormally and massively activation of hemostasis and fibrinolysis

Question 19

when chronic DIC is typically seen

Answer 19

advanced malignancy (pancreatic, gastric, ovarian, brain tumors)