Other Disorders of Hemostasis

Question 1

Mechanism of heparin-induced thrombocytopenia

Answer 1

heparin complexes with PF4 (platelet factor 4)
IgG is produced against this complex
feared complication: thrombosis when remnants thrown out

Question 2

Feared complication of heparin-induced thrombocytopenia

Answer 2

peripheral thrombosis

from remnants being thrown into circulation

Question 3

What OB complication results in DIC

Answer 3

tissue thromboplasin into circulation
from amniotic fluid
activates coagulation cascade

Question 4

Animal whose bite can precipitate DIC

Answer 4

rattlesnake bite

Question 5

How to tell the difference between DIC and disorders of fibrinolysis in labs

Answer 5

DIC has + D-dimers
disorders of fibrinolysis have negative D-dimers
*because in disorders of fibrinolysis, the clot never gets to form so there are no D-dimers

Question 6

Tx of DIC

Answer 6

underlying cause

blood products + cryoprecipitate

Question 7

What normally inactivates plasmin

Answer 7

α2-antiplasmin

produced by liver

Question 8

How are clots normally resolved

Answer 8

plasminogen –> plasmin

plasmin breaks down fibrin into D-dimers

Question 9

Labs in disorders of fibrinolysis

Answer 9

negative D-dimers
positive fibrinogen split products
*note fibrinogen and not fibrin, which would be D-dimers

Question 10

Plasmin actions

Answer 10

cleaves fibrin
cleaves fibrinogen
destroys factors
blocks platelet aggregation
*breaks clots up and doesn't allow clots to be formed

Question 11

2 common causes of disorders of fibrinolysis

Answer 11

urokinase release during radical prostatectomy

cirrhosis: decreased α2-antiplasmin release

Question 12

Tx of disorders of fibrinolysis

Answer 12

aminocaproic acid
blocks activation of plasminogen
“caps” the bleed

Question 13

Aminocaproic acid
MOA
TU

Answer 13

MOA: blocks activation of plasminogen
TU: disorders of fibrinolysis
“caps” the bleed