Coagulation / Bleeding Disorders Flashcards
What type of vessels use primary hemostasis the most?
arteries
What type of vessels use secondary hemostasis the most?
veins
i.e: DVT
Platelet function assay
another name for closure time
measures how long for primary hemostasis to form platelet plug in test tube
vWF antigen vs. activity
antigen is more specific
low vWF antigen and activity can mean vWD
Ristocetin co-factor
another term for vWF activity
Type I vWD
reduced vWF number but it functions correctly overall
thrombocytopenia
low platelet count
What is common signs of thrombocytopenia?
purpura and petechiae
what is there a risk of with Thrombocytopenia?
spontaneous bleeding due to lack of platelets
high risk of bleeding thrombocytopenia values
<10,000
low risk of bleeding thrombocytopenia values
<20,000
Immune Thrombocytopenic Purpura
viral infection causes an immune response against platelets
Immune Thrombocytopenic Purpura treatment
platelet transfusion will not work as antibodies will just degrade them
need immunosuppression or splenectomy
problem with platelets = primary hemostasis problem
What conditions cause thrombocytopenia by increased consumption of platelets?
DIC, HUS, Heparin Induced Thrombocytopenia
What specifically does aspirin affect?
aspirin = antiplatelet
prevents step 2 of primary hemostasis (no degranulation of platelets)
COX1 and platelets
aspirin activates COX1 which releases prostaglandins
prostaglandins prevent platelet granulation release
what type of bleeding indicates primary hemostasis?
mucosal
what type of bleeding indicates secondary hemostasis?
deep / joint
for secondary hemolysis, what labs are checked next?
PT and PTT
then mixing studies
why are platelets seen more in the arteries?
platelets are more stable in that higher pressure system
what is the primary tests for primary hemostasis?
vWF and ITP
*looking for a platelet problem
what are the vitamin K dependent factors?
2, 7, 9, 10
What 2 things should you think about if both PTT and PT are delayed?
fibrinogen or vitamin K def.
common pathway problem
hemarthrosis
swollen, hot joint
common in hemophilia patients
ITP stands for …
immune thrombocytopenia purpura
difference and similaries in vWD and ITP
both: affect the primary hemostasis pathway
difference: ITP is more diffuse. Platelets are also normal in vWD but low in ITP
platelet count in vWD
normal!
have a deficiency of vWF, not platelets
What do you treat vWD with?
DDAVP
releases more vWF from endothelial cells
could also give recombinant vWF infusions
What do you treat non-immune thromocytopenia with?
platelet transfusion
What do you treat secondary hemostasis disorders with?
either recombinant factors or fibrinogen transfusion
What 4 conditions can lead to an unprovoked clot?
Factor V Leiden
Prothrombin
Protein C/S not working
Antithrombin III not working
What can an EKG show in setting of PE?
a right heart strain due to blockage of the pulmonary vein putting more pressure on the heart
What is most definitive way to look for PE?
CTA of chest
antiplatelet drugs
aspirin and clopidigrel
anticoagulation drugs
warfarin, heparin, NOAC
how does clopidigrel work?
binds to the GPIIb/GPIIIa complex through P2Y12
why don’t we give thrombolytics, like tPA more?
they have high associated bleeding risk
use for acute PE
why don’t we need to check PT/PTT for coagulation disorders?
those tests look at bleeding disorders
