Lecture 3 - Hemostasis disorders

Question 1

what is virchow’s triad?

Answer 1

hypercoaguable state + endothelial dysfunction + stasis/abnormal blood flow

Question 2

3 things activated platelets relase

Answer 2

calcium, TXA2, ADP

Question 3

intrinsic pathway:
factors involved = 
what measures it = 
drug that affects it =
activated by =

Answer 3

12, 11, 9, 8;
aPTT;
heparin;
subendothelial collagen

Question 4

extrinsic pathway:
factors involved = 
what measures it =
drug that affects it =
activated by =

Answer 4

7;
PT;
warfarin;
tissue factor

Question 5

INR:
used to follow patients with ___;
normal value?

Answer 5

warfarin therapy;

1; greater than 1 = abnormality

Question 6

2 places VWF is released from

Answer 6

WP bodies in endothelial cells;

alpha granules in plateletes

Question 7

two things VWF does

Answer 7

binds subendothelial collagen and Gp1B receptor;

protects factor 8 from cleavage

Question 8

VW disease:
platelet count?
Bleeding time?
PT?
PTT?

Answer 8

normal;
increased;
normal;
increased (loss of factor 8 protection);

vw disease is usually due to decreased levels of VWF

Question 9

what does ristocetin cofactor do usually?

what does it to in VW disease?

Answer 9

usually activates VWF to bind Gp1b = platelet agg;

doesn’t work ie poor platelet agg

Question 10

general treatment for VW disease? what does it do?

Answer 10

desmopressin = causes release of VEF from endothelial cells

Question 11

Hemophilias: defeciency of what factor?
A =
B =
C =

which are XR and which are AR?

Answer 11

8 , 9, 11;

A and B = X recessive;
C = Autosomal Recessive

Question 12

hemophilias cause an increase in ___.

name 2 symptoms

Answer 12

aPPT;

rebleeding after surgery, deep joint/tissue bleeding

Question 13

DIC:
Platelet count?
Bleeding time?
PTT?
PT?
d-dimer?

Answer 13

decreased;
increased;
increased;
increased;
increased (fibrin degradation product)

Question 14

causes of DIC:

trauma, obsetric problems due to ______, ______, ______

Answer 14

tissue factor in amniotic fluid;

APL; sepsis

Question 15

what causes an increase in bleeding time on labs?

Answer 15

platelet disorder ie decreased platelets

Question 16

immune thrombocytopenia:
usually due to antibodies against ____;
in younger patients, usually due to ____;
in older patients, usually due to ___

Answer 16

Gp2b3a receptors;
acute antecedent illness ie virus;
idiopathic (chronic)

Question 17

immune thrombocytopenia:

where are the Abs made? where are the platelets destroyed? treatment that resolves both of these problems?

Answer 17

spleen, spleen, splenectomy;

first line treatment is steroids or IV Ig

Question 18

clotting factor inhibitors:
usually anti-factor ____.
what are the results of mixing study?

Answer 18

8;

mixing study does not fix clotting factor inhibitors; it does fix a deficiency (ie hemophilia)