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Cardiogenic Shock

  • Shock – clinical syndrome that develops when there is critical impairment of tissue perfusion due to some form of acute circulatory failure
  • Cardiogenic shock – failure of pumping action of the heart, resulting in ↓CO, and ↓end-organ perfusion
    • Presence of the following (despite adequate LV filling pressure)
      • Sustained hypotension – SBP<90mmHg for >30 mins
      • Tissue hypoperfusion – cold peripheries, oliguria
      • MCC – LHF > pulmonary congestion > hypoperfusion

Etiology

Pathophysiology – see diagram

  • ↓ coronary perfusion pressure and CO and ↑ myocardial oxygen demand
    • Create a vicious cycle that leads to cardiogenic shock

Clinical features

  • Chest pain, N + V, dyspnoea, sweating, palpitations
  • Pale, cold skin
  • Poor peripheral pulses
  • Hypotenison
  • Tachy/bradycardia, murmurs
  • Pulmonary crackles
  • Oliguria
  • Altered mental state

Management

  • ABC
    • Airway + breathing – intubation/mechanical ventilation if needed; oxygen
    • Circulation – gain venous access to take blood for investigation and administration of IV fluids
  • Monitor vital signs
    • Pulse, BP, respiratory rate, O2 sats
  • Insert urinary catheter
  • Investigations
    • U+E, creatinine
    • LFTs
    • Cardiac enzymes, ECG, CXR, Echo
    • FBCs
    • ABGs
    • BNP
  • Inotropic drugs – Vasopressors (adrenaline, dobutamine)
  • Revascularisation

If CO is inadequate and contractility is poor

  • Reduce afterload
    • Hydralazine [25mg t.i.d]
    • Intra-aortic balloon bump counterpulsation (IABP)  – reduces afterload, increases CO and coronary perfusion
  • Increase preload
  • Improve contractility – inotropes (see above)
  • Control rate and rhythm
    • Correct hypokalaemia and hypomagnesaemia
    • IV amiodarone – to control ventricular rate and restore sinus rhythm
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