hemorrhage and hemostasis

Question 1

extravasation of blood due to rupture of blood vessels is called

Answer 1

Hemorrhage

Question 2

accumulation of extravasated blood into the TISSUE is called

Answer 2

Hematoma

Question 3

Hemorrhages of 1-2mm into the skin, mucous membrane or serosal surface are called

Answer 3

Petechiae
usually linked with local increase in intravascular pressure and low abnormal platelet function

Question 4

Hemorrhages into the skin of >3mm but <1cm are known as

Answer 4

pupura
usually same condition as petechiae
and can also be secondary to trauma and vascular inflammation or increased vascular fragility

Question 5

hemorrhages into the skin of 1-2cm are called

Answer 5

Ecchymoses

Question 6

The color changes observed in bruises(echymoses) which are from
a. red-blue color to
b. blue-green/yellow to
c. golden brown color
is due to what events

Answer 6

phagocytosis by macrophages is responsible for these colour changes
a is due to hemoglobin
b is due to convertion to biliverdin and bilirubin
c is due to conversion into hemosiderin

Question 7

derangement of hemostasis are broadly classified into 2 types which are

Answer 7

hemorrhagic disorder(excess bleeding)
thrombotic disorder(excess clotting with formation of blood clot within intact vessels)

Question 8

in what condition can the two division of hemostatic disorder occur

Answer 8

DIC
disseminated intravascular coagulation
in DIC there is a generalized activation of clotting factors causing it to be depleted(forms a clot) and then prevent clotting of bleeding sites (because all the clotting factors have been used up in another place)

Question 9

list the 4 sequence of events in hemostasis at the site of injury

Answer 9

arteriolar vasoconstriction
primary hemostasis(formation of platelet plug)
secondary hemostasis(deposition of fibrin)
clot stabilization and resorption

Question 10

arteriolar vasoconstriction is mediated by two mechanisms which are

Answer 10

endothelin
reflex neurogenic mechanism

nb: arterolar vasoconstriction is a transient mechanism of hemostasis

Question 11

the endothelium exhibits both anti thrombic and procoagulant activities
T or F

Answer 11

T
the intact endothelium has antithrombic and fibrinolytic activity but when it is injured it exhibits procoagulant properties

Question 12

list 3 antithrombic properties of endothelium

Answer 12

1. prevents/shield platelet from coming in contact with collagen and vwf
2. production of prostacyclin and NO which causes vasodilation and prevent platelet aggregation
3. Adenosine diphosphatase which degrades ADP and inhibits platelet aggregation

endothelial cells can also bind thrombin and alter it’s function as a coagulation

Question 13

list 4 factors expressed by endothelium that actively opposes coagulation

Answer 13

Thrombomodulin(thrombin receptor expressed on endothelial)
Heparin like substance(to act as cofactor with antithrombin 3)
protein C receptor
tissue factor pathway inhibitor

Question 14

list a substance produced by endothelium that inhibits fibrin formation (fibrinolytic)

Answer 14

tissue type plasminogen activator

Question 15

list 3 prothrombotic properties of injured epithelium

Answer 15

1.secretion of plasminogen activator inhibitor (PAI)
2.release of tissue factor which activates extrinsic pathway
3.exposure of vwf

Question 16

list the 2 types of platelet granules

Answer 16

alpha and dense granules

Question 17

alpha granules contain substances such as
P-selectin
Factor V and VIII
fibrinogen
Platelet derived growth factor
TGF-Beta
T or F

Answer 17

T

Question 18

dense granules contain
ATP
ADP
Calcium
Serotinin
Histamine
T or F

Answer 18

T

Question 19

on contact with vwf and collagen, platelets undergo 3 reactions which are

Answer 19

adhesion and shape change
release of granules and contents
aggregation

Question 20

if there is a genetic defect in the gene thaf codes for glycoprotein 1b (Gp1b) that condition is known as

Answer 20

Bernard Soulier syndrome

Question 21

glycoprotein 2b/3a allow binding of fibrinogen between adjacent platelet leading to their aggregation
T or F

Answer 21

T

Question 22

deficiency of glycoprotein 2b/3a is called

Answer 22

Glenzmann syndrome

Question 23

platelet contraction is dependent on the cytoskeleton of platelets and it is irreversible
T or F

Answer 23

T

Question 24

prostacyclin is secreted by platelets while thromboxane is secreted by endothelial cell
T or F

Answer 24

F
the other way round

Question 25

Aspirin which is given to patients at risk of coronary thrombosis acts by

Answer 25

inhibiting thromboxane A2 synthesis

Question 26

deficiency of coagulation factors are called

Answer 26

Hemophilia

Question 27

list the two known plasminogen activator

Answer 27

urokinase like PA
tissue type PA (t-PA)

Question 28

List the 4 natural anticoagulants and what they inhibit

Answer 28

Antithrombin 3 - inactivates thrombin and factor x(thrombin activator)
Protein C and S - inactivates factor V and VIII
Plasmin - breaks down fibrin and interferes with it’s polymerization
which produces fibrin split products

Question 29

Fibrin split products are elevated in what condition

Answer 29

DIC
Disseminated intravascular clotting