Synchronized cardioversion

See critical care quick reference for doses by weight.


It is important to note that the procedure for and indications differ between defibrillation and cardioversion

Defibrillation (Unsynchronized cardioversion)

Synchronized Cardioversion


  • None

Equipment Needed

  • Defibrillator
  • Consider sedation medication in conscious patient (e.g. etomidate, ketamine), but do not delay procedure in unstable patient



  • Apply pads (anterior-posterior placement is preferred)
  • Select appropriate Joule setting
  • Ensure machine is "synced" before each discharge
  • Give sedation, if indicated
  • Cardiovert
  • Repeat PRN
  • Ensure R or S wave is bigger than T wave
    • Machine may read T wave as depolarization and shock during an actual repolarization phase
    • May induce shock on T and subsequent VT/VF
    • Move leads to avoid this


Initial recommendations:

  • Tachycardia with pulse
    • Narrow regular: 50-100 J
    • Narrow irregular
      • Biphasic: 120-200 J
      • Monophasic: 200 J
    • Wide regular: 100 J
    • Wide irregular: defibrilate (NOT synchronized)


See Also

External Links


  • AHA 2010 ACLS Recommendations