Venous thrombosis

Question 1

Venous drainage is a:

low/high pressure system

Answer 1

low pressure

Question 2

In the veins, platelets/coagulation cascade is activated

Answer 2

platelets are NOT activated

coagulation cascade IS activated

Question 3

platelet/fibrin rich clots form in veins

Answer 3

fibrin rich

Question 4

what are the features of Virchow’s triad

Answer 4

stasis
vessel damage
hypercoaguability

Question 5

risk factors for stasis

Answer 5

older age 
obesity 
paralysis 
pregnancy 
trauma/surgery 
malignancy

Question 6

risk factors for vessel damage

Answer 6

previous thrombosis

older age

Question 7

risk factors for hypercoaguability

Answer 7

Anything that increases clotting factors:
malignancy 
age 
pregnancy and puerperium 
oestrogen therapy 
trauma/surgery
infection 
thrombophilia

Question 8

what is the overall pathophysiology of thrombophilias

Answer 8

decreased levels of natural anticoagulant defences

haemostasis and clot formation is not switched off

Question 9

define thrombophilia

Answer 9

hereditary/acquired disorders of haemostasis which are likely to predispose to thrombosis

Question 10

what are mechanisms behind thrombophilias

Answer 10

increased platelet or fibrin formation

decreased fibrinolysis or coagulation defences

Question 11

what are the bodies natural anticoagulants and their functions

Answer 11

antithrombin - switches off thrombin

Protein C+S - switch off factors V + VIII

Question 12

what are hereditary thrombophilias

Answer 12

genetic defects which increase the tendency to form abnormal, premature and recurrent thromboses

Question 13

list causes of hereditary thrombophilias

Answer 13

Factor V Leiden 
Prothrombin 20210 mutation 
Anti thrombin deficiency 
Protein C deficiency 
Protein S deficiency

Question 14

how does Factor V Leiden cause thrombophilia

Answer 14

impairs ability of protein C+S to switch off factor V

Question 15

how does Prothrombin 20210 mutation cause thrombophilia

Answer 15

increases expression of prothrombin via F2 gene mutation

Question 16

how does antithrombin deficiency cause thrombophilia

Answer 16

failure to switch off thrombin

Question 17

how does Protein C+S deficiency cause thrombophilia

Answer 17

inability to switch off factor V and VIII

Question 18

who would you consider doing a hereditary hrombophilia screen in

Answer 18

venous thrombosis <45 y/o
recurrent thrombosis 
unusual thrombosis 
FH thrombosis 
FH thrombophilia

Question 19

what is the management of hereditary thrombophilias

Answer 19

avoid risk factors
short term prophylaxis
short term anticoagulation
long term anticoagulation

Question 20

Risk factors for recurrent thrombosis

which one is most important

Answer 20

previous thrombosis - most important
spontaneous thrombosis with no risk factors
FH
screening results

Question 21

what is a cause of acquired thrombophilia

Answer 21

anti phospholipid syndrome APLS

Question 22

what is APLS

Answer 22

autoimmune condition attacking B2 glycoprotein 1 which increases risk of arterial AND venous thrombosis by activating primary and secondary haemostasis as well as causing damage to vessel walls

Question 23

clinical features of APLS

Answer 23

recurrent thrombosis (arterial and venous)
recurrent foetal loss
mild thrombocytopaenia

Question 24

investigations for APLS

Answer 24

antibodies: anti-B2glycoprotein, lupus anticoagulant, anti-cardiolipin
APTT prolonged

Question 25

which conditions are associated with APLS

Answer 25

SLE
lymphoproliferative disorders
viral - EBV
drugs

Question 26

management of APLS

Answer 26

antiplatelets AND anticoagulants

because of thrombosis risk in arteries and veins