Haemodynamic disorders Flashcards
Definition of oedema
Abnormal increase in interstitial fluid
aetiological classification of oedema
hypertension
inflammation
Reduced plasma oncotic pressure (reduced albumin) - generalised oedema
Lymphatic obstruction (tumour/lymph node dissection/chronic inflammation)
Sodium retention - reduced cardiac output - water retention - renin-angiotensin system
generalised oedema, and causes
in serous cavities
Congestive heart failure, Hypoproteinaemia (low protein content), Nutritional oedema
localised oedema, and causes
cerebral and pulmonary
Left heart failure, Inflammation, Venous hypertension, Lymphatic obstruction
Pulmonary consequences of oedema
dyspnoea (breathlessness) - worse when flat (orthopnoea)
fluid in alveolar space - bacterial infection
Define shock
systemic hypotension
System hypoxia
causes of shock - general
Low cardiac output
reduced circulatory volume
Cause of cardiogenic shock
acute MI
arrhythmia
cardiac tamponade (fluid in pericardium - compress heart)
cause of septic shock
bacterial infection activate immune system (endotoxins - complement pathway, damage endothelial cells, tumour necrosis factor)
vasodilation
blood pooling
SIRS - systemic inflammatory response syndrome
severe sepsis and hypoperfusion
cause of hypovolaemic shock
loss blood due to haemorrhage or fluid loss
kidney, brain skin
cause of neurogenic shock
loss of vascular tone
cord injury
anaesthetic medication
type of shock
septic
neurogenic
hypovolaemic
cardiogenic
What is a haemorrhage
extravasion of blood due to a vessel rupture
causes of haemorrhage
trauma
intrinsic disease of vessel - amyloid/collagen vascular disease.
consequences of haemorrhage
risk hypovalaemia
shock
death
Thrombosis definition
Abnormal blood clot in circulatory system
embolism definition
Abnormal material in circulatory system that has travelled to site distant from origin
infarction definition
Tissue necrosis due to ischemia
cause of thrombosis
endothelial injury
stasis/turbulent blood flow
blood hypercoagulability
How does endothelial injury cause a thrombosis
caused because high blood flow and high levels of stress
platelet aggregation
How does stasis/turbulent blood flow cause thrombosis
lead to endothelial injury
stasis - disruption lamina blood flow - venous thrombi
turbulent blood flow - endothelial damage - localised stasis - arterial and cardiac thrombi
cause of hyopercoagulability
blood disease
primary - factor V mutation, protein C deficiency
secondary - multifactorial, cancer, age, obesity, the pill
fate of thrombi
propagation - occumulation more fibrin and platelets
embolization - dislodge
dissolution - fibrinolysis
organisation and recanalization - envelope fibroblasts, endothelial cells, smooth muscle cells, capillary channels develop
consequence of thrombi
venous thrombosis - pulmonary embolism
arterial thrombosis - ischemia of tissue/infarction
consequences of embolism
block vessels
venous thromboembolism - pulmonary thromboembolism - breathless, chest pain, dizziness, death
systemic emboli - TIA, stroke, bowel infarction, limb ischemia
Cause of embolism
fragments dislodged thrombus
fat, air, amniotic fluid, tumour
cause of infarction
thrombotic/embolic vascular occlusion
vasculitis
haematological abnormalities
consequences of infarction
repair - permanent loss of structural tissue
