Blood and vascular disorders

Question 1

Oedema

Answer 1

• abnormal accumulation of fluid in interstitial spaces
• causes include:
  + increased capillary permeability
  ~ e.g. inflammation, burns
  + decreased plasma oncotic (colloid osmotic) pressure
  ~ e.g. liver failure, kidney disease, protein malnutrition
  + increased venous pressure
  ~ e.g. heart failure

Question 2

Haemorrhage

Answer 2

• loss of blood into extravascular space
• rupture of large vessel is often due to trauma,
  atherosclerosis
• accumulation of blood = haematoma
• rapid loss of 20% of blood volume can lead to
  haemorrhagic shock

Question 3

Thrombosis

Answer 3

• stationary blood clot in vessel = thrombus
• 3 reasons why they occur
  + abnormal (slow or turbulent) blood flow e.g. prolonged
  bed rest, damaged valve
  + excessive coagulation e.g. inherited factors
  + damage to endothelium of blood vessel e.g.
  hypertension, following myocardial infarction

Question 4

Arterial thrombus

Answer 4

• mainly found in coronary, cerebral, femoral arteries
• mainly due to atherosclerosis causing
  + damage to endothelium and abnormal blood flow

Question 5

Venous thrombosis

Answer 5

• 95% occur in superficial or deep veins of leg
• mainly due to:
  + slow blood flow
  + increased coagulation

Question 6

Embolism

Answer 6

• an embolism can break off from a thrombus
• it travels downstream and lodges in a smaller diameter
  vessel
  + e.g in arteries of brain causing stroke

Question 7

Hypertension

Answer 7

• hypertension = resting blood pressure > 140/90 mm Hg
• 90% cases there is no evident cause
• causes damage to artery walls, accelerates
  atherosclerosis

Question 8

Atherosclerosis risk factors

Answer 8

• increasing age
• male gender
• genetics
• smoking
• poorly-controlled diabetes
• hypertension

Question 9

Aneurysm

Answer 9

• is localised permanent dilation of part of blood vessel/heart
• usually occurs in aorta (AAA)
  + atherosclerotic plaque causes vessel wall weakness

Question 10

Left-side heart failure

Answer 10

- commonly due to 
   \+ ischaemic heart disease
   \+ hypertension
   \+ aortic/mitral valve disease
- leads to
   \+ pulmonary congestion
   \+ reduced CO

Question 11

Right-side heart failure

Answer 11

• usually a consequence of LHF
• leads to
  + venous congestion