Aetiology of acute hypotension

Acute hypotension may be caused by:

• cardiac malfunction:
  • arrhythmia
  • myocardial infarction
  • valvular defects e.g. aortic regurgitation
  • cardiac tamponade
  • massive pulmonary embolism
  • tension pneumothorax
    
    
• hypovolaemia:
  • blood loss e.g. GI bleed, abdominal aortic aneurysm
  • urinary loss
  • plasma loss e.g. burns
  • third space losses e.g. pancreatitis
  • dehydration e.g. diarrhoea, coma, heat exhaustion
    
    
• vasodilatation:
  • drugs e.g. ACE inhibitors, beta-blockers
  • sepsis, especially Gram-negative shock
  • heat exhaustion