Thrombosis, Embolism and Infarction

Question 1

what are other potential bases of endothelial injury?

Answer 1

\+ radiation injury
\+ chemical agents
\+ bacterial toxins or endotoxins
\+ immunologic injuries
\+ neoplastic movement

Question 2

what are the roles of platelets in thrombosis?

Answer 2

+ adhesion
+ secretion
+ aggregation

Question 3

what happens with turbulent blood flow and stasis?

Answer 3

+ disrupts laminar flow
+ prevents dilution of coagulation factors
+ stops inflow of inhibitors of clotting factors
+ promotes endothelial cell activation

Question 4

what are primary (genetic) factors that can cause hyercoagulability?

Answer 4

+ mutation in factor V gene = leiden mutation
+ antithrombin III deficiency
+ protein C and S deficiency

Question 5

what are high risk secondary (acquired) factors that can cause hypercoagilability?

Answer 5

\+ immobilisation
\+ MI
\+ tissue damage
\+ CA
\+ prosthetic valves
\+ DIC

Question 6

what are lower risk secondary (acquired) factors that can cause hypercoagilability?

Answer 6

\+ AF
\+ cardiomyopathy
\+ nephrotic syndrome
\+ oral contraceptive
\+ sickle cell anaemia
\+ smoking

Question 7

what are features of arterial thrombi?

Answer 7

\+ usually occlusive
\+ may be mural
\+ frequent in these arteries: 
- coronary
- cerebral
- femoral
\+ grey-white and friable

Question 8

what are features of venous thrombosis (phlebothrombosis)?

Answer 8

\+ invariably occlusive
\+ dark red
\+ affects veins of lower extremities (90%):
- deep calf
- femoral
- popliteal
- iliac

Question 9

what are signs of an arterial thrombosis?

Answer 9

\+ loss of pulses distal to thrombus
\+ area becomes:
- Perishing cold
- Pale
- Painful
- paraesthesia
\+ eventually tissue dies and gangrene results

Question 10

what are symptoms of venous thrombi in superficial veins?

Answer 10

\+ congestion
\+ swelling 
\+ pain
\+ tenderness
\+ rarely embolises

Question 11

what are symptoms on venous thrombi in deep veins?

Answer 11

+ foot and ankle oedema
+ Homans’ sign
+ could by asymptomatic, only recognised when embolised

Question 12

what are treatment options for thrombi/preventing emboli?

Answer 12

+ stockings
+ anticoagulant drugs:
- heparin
- warfarin

Question 13

what are the 5 classifications of emboli?

Answer 13

\+ pulmonary
\+ systemic
\+ amniotic
\+ air
\+ fat

Question 14

what is a barotrauma?

Answer 14

injury caused by air embolism

Question 15

what can cause an air embolism to occur?

Answer 15

+ delivery or abortion
+ pneumothorax
+ injury to lung or chest wall
+ Caisson disease or decompression sickness

Question 16

what is the treatment for caisson disease?

Answer 16

recompression chamber

Question 17

how does caisson disease occur?

Answer 17

+ individual decompresses too rapidly

+ helium and nitrogen form gaseous emboli

Question 18

what causes amniotic fluid embolism?

Answer 18

infusion of amniotic fluid into maternal circulation

Question 19

what is an infarct?

Answer 19

an area of ischaemic necrosis caused by occlusion of arterial supply or venous drainage in a particular tissue

Question 20

besides thrombosis and embolism, what are the other causes of infarcts?

Answer 20

\+ vasospasm
\+ expansion of atheroma
\+ compression of a vessel
\+ twisting of vessels
\+ traumatic rupture

Question 21

what are factors that influence the development of an infarct?

Answer 21

+ nature of vascular supply (single/dual)
+ rate of development of occlusion
+ vulnerability to hypoxia
+ oxygen content of blood

Question 22

what are the different types of infarcts?

Answer 22

+ red (haemorrhagic)
+ white (anaemic)
+ septic or bland

Question 23

where do red infarcts occur?

Answer 23

+ venous occlusions
+ loose tissues
+ tissues with dual circulation

Question 24

where do white infarcts occur?

Answer 24

+ arterial occlusions

+ solid organs