Vascular disorders

Question 1

thrombus

Answer 1

solid mass of blood constituents formed during life

Question 2

virchows triad

Answer 2

predisposing factors for thrombus formation

1. endothelial injury
2. abnormal blood flow
3. hypercoagulability

Question 3

endothelial injury: changes in vessel wall

Answer 3

inflammation
trauma
atherosclerosis

Question 4

abnormal blood flow

Answer 4

stasis
turbulence
aneurysms

Question 5

hypercoagulability: changes in blood constituents

Answer 5

viscosity

clotting factors

Question 6

atheroma

Answer 6

collection of lipid filled cells within the wall of the blood vessel

Question 7

lines of zahn

Answer 7

alternating layers of blood constituents

Question 8

arterial thrombosis

Answer 8

most commonly caused by thrombi formed superimposed on atheroma

consequences: tissue infarct

Question 9

venous thrombosis

Answer 9

most commonly caused due to stasis and immobilisation e.g. DVT

consequences: collection of fluid

Question 10

consequences of thrombi (4 to consider)

Answer 10

1. lysis and resolution
   the thrombus will lyse and become broken down
2. organisation
   inflammation resulting in tissue loss there may be scar tissue or organisation and that may lead to narrowing of blood vessels
3. recanalisation
   some blood manages to filter through and restore some limited blood supply leaving behind scar and residual thrombus.
4. embolism
   thrombus breaks off and travels further downstream and travels in the direction of the blood flow until it reaches a a vessel through which it cannot pass through

Question 11

embolism

Answer 11

an intravascular mass and is not always a thrombus but it can be a broken fragment from a thrombus

it can also be solid, liquid or gas

it is a mass that has travelled away further downstream from its site of origin.

Question 12

embolism consequences

Answer 12

obstruction

metastases (in the case of a tumour)

spread of infection

tissue destruction

Question 13

pulmonary embolism

Answer 13

origin is the veins and right side of the heart. destination is anywhere along the pulmonary artery.

Question 14

systemic embolism

Answer 14

origin is the arteries and left side of the heart. destination is systemic

Question 15

ischaemia

Answer 15

the inadequate perfusion of blood to an organ or part of it

Question 16

infarction

Answer 16

death of tissue due to ischemia

this cell death is necrotic and pathological

doesnt have to be a complete block of the blood supply but sufficient block that the tissue is not adequately perfused.

Question 17

factors influencing ischaemia

Answer 17

rate of occlusion
tissue vulnerability
anatomy of the vascular supply

Question 18

shape of infarction

Answer 18

typically wedge shaped with apex at point of occlusion

in the lung/kidney it is conical

brain it is fluid filled cyst

Question 19

classification of infarction

Answer 19

red/haemorrhagic:
in the lung, intestine, liver

in organs that are composed of loose tissue.

occurs where there is a venous occlusion i.e. doesn’t occur because of inadequate perfusion but because of poor drainage

pale/anaemic:
heart, kidney, spleen

can be seen in solid organs containing dense tissue

seen in end arterial circulation i.e. circulation only having singular blood supply

Question 20

types of shock

Answer 20

cardiogenic: low cardiac output
hypovolaemic: reduction in circulating volume

septic shock: infection resulting in systemic inflammatory response

neurogenic: loss of vascular tone due to spinal injury

anaphylactic shock: systemic vasodilation and increased vascular permeability.

Question 21

phlebothrombosis vs thrombophlebitis

Answer 21

phlebothrombosis is a thrombosis of the veins.

thrombophlebitis is an inflammatory reaction to phlebothrombis.