Thrombosis, Embolism And Shock Flashcards
Where may thrombosis occur?
Arteries, veins and capillaries
What are the 3 elements of Virchows triad?
- Abnormalities of the vessel wall
- Abnormalities of blood flow
- Abnormalities of the bloods constituents
What abnormalities can occur in artery walls that promote thrombosis?
Atheroma
What abnormalities can occur in heart walls that promote thrombosis?
MI or rheumatic endocarditis
What abnormalities can occur in vein walls that promote thrombosis?
Trauma, inflammation, chemical damage
What abnormalities can occur in capillary walls that promote thrombosis?
Inflammation
What abnormalities of blood flow affect arteries?
Turbulence - aneurysms, plaques, spasm
What abnormalities of blood flow felt the heart?
Atrial fibrillation
Aneurysms
What abnormalities of blood flow affect veins?
Local: compression, inactivity
General: heart failure, Circulatory shock
Name 4 things that increase viscosity
Polycythaemia
Dehydration
Chronic hypoxia
Polycythaemia rubra vera
What is the most common resolution of thrombi?
Fibrinolysis
Define embolism
Transport of abnormal material (solid, liquid or gas) by the bloodstream and its impacting a blood vessel
What is a common cause of fat emboli?
Multiple bone fractures breaking up the fat below
How might gas emboli occur?
Infusions
Vascular surgery
Caissons disease
Define shock
A physiological state characterised by a systemic reduction in tissue perfusion, resulting in reduced tissue oxygen delivery and insufficient removal of cellular metabolic products resulting in tissue injury
When does hypovolaemic shock occur?
Haemorrhage - int or ext
Severe burns
When does cardiogenic shock occur?
Large acute MI
Acute cardiac disease
What causes septic shock?
Endotoxins from gram negative bacteria
Exotoxins from gram positive bacteria
What causes Anaphylactic shock?
Severe allergic reaction
What causes neurogenic shock?
Spinal cord trauma
Regional anaesthesia
What causes obstructive shock?
Cardiac tamponade
Tension pneumothorax
Massive pulmonary embolism
Name the 8 clinical features of shock
- Low systolic bp
- Tachycardia
- Respiratory v high or v low
- Low urine output
- Metabolic acidosis
- Hypoxia
- Cutaneous vasodilation or vasoconstriction
- Mood: lethargy, agitation, anxiety
Define thrombosis
Formation of a semi solid mass from the constituents of blood
