OnlineMedEd: Intern Content - "Bleeding" Flashcards
____________ binds to damaged endothelium and connects to glycoprotein Ib on platelets.
von Willebrand factor
Which two molecules mediate platelet activation?
- TXA2
* ADP
Aggregation is mediated by which protein?
Glycoprotein IIb/IIIa
The common pathway of coagulation factors include which proteins?
- I
- II
- V
- X
(“There’s one five in five, and two fives in ten.”)
Factor Ia is also called _______________.
fibrin
DAPT inhibits which step of primary hemostasis?
Activation
ASA inhibits TXA. Clopidogrel inhibits ADP.
Why is PT useful in tracking warfarin therapy?
Factor VII (which determines PT) has the shortest half-life
List the features of dysfunctional primary hemostasis.
- Oral bleeding (tooth pulling)
- Vaginal bleeding
- Petechiae
List the features of dysfunctional secondary hemostasis.
- Hemarthrosis
* Bleeding after surgery
What should you test to assess primary hemostasis?
- Platelet count
* vWF factor
Thrombocytopenia results from what three categories of causes?
• Production:
- Bone marrow suppression
- Aplastic anemia
- Cirrhosis
- Bone marrow cancer
•Consumption:
- DIC
- TTP
- HIT
- ITP
•Sequestration:
- Splenomegaly
Review the causes of platelet dysfunction.
- vWF deficiency
- Bernard-Soulier
- Glanzmann thrombasthenia
- Uremia (uremic frost coats platelets)
- NSAIDs
What study do you order to evaluate for disorders of secondary hemostasis?
Mixing study
- A mixing study that shows persistent prolonged PT/PTT is due to inhibitors.
- A mixing study that shows corrected PT/PTT is due to factor deficiency (likely genetic causes).
Why are those with cirrhosis thrombocytopenic?
They constantly have mild DIC (which also contributes to the prolonged PT/PTT).
