Treatment of a tachyarrythmia that has been present for less than 24 hours with an aim to revert to sinus rhythm.
Treatment of a tachyarrythmia that has been present for less than 24 hours when pharmacological measures have failed.
Treatment of a tachyarrythmia when the patient shows signs of decompensation:
Chest pain, confusion, hypotension or signs of heart failure
Equipment and staff required for DC cardioversion:
An anaesthetist for safe sedation
Defibrillator
Cardiac monitor
Defibrillator pads
N.B. In some hospital trusts cardioversion may be done under trans-oesophageal echo (TOE) guidance to ensure there is no right atrial thrombus. Liaise with the cardiology team if you think this is necessary.
Contraindications to DC cardioversion:
No clear onset of the history of palpitations
Previous paroxysms of tachyarrythmia and not on anticoagulation
Known atrial thrombus
Pre-procedure:
Gain written consent from the patient
Risks of sedation; pain (musculoskeletal or minor skin injury); failure (approx. 20%); stroke (<1%); bradycardia
Ensure the area where de-fibrillator pads are to be placed is shaved and dry and that jewellery is removed
Ensure cardiac monitoring is in place
Ensure anaesthetist is happy for you to proceed
Procedure for DC cardioversion:
Place the defibrillator pads to ensure the current will pass across the heart.
This can be in the conventional position, anterio-posterior, postero-lateral or bi axillary
Sedation as necessary
Turn on the defibrillator and press ‘Sync’
Check your trusts’ policy on level of energy but a rough guide is 100J,150J, 200J
Charge the defibrillator ensuring everyone is clear including the oxygen
Deliver a safe shock as per ALS guidelines
Confirm presence of a pulse
Check the monitor for sinus rhythm
Two further shocks (escalating energy) can be given if necessary.
Video (from the US) on elective DC cardioversion – note some differences from the method described above but principles are the same.
Post-procedure:
Continue cardiac monitoring
Post-procedure observations
Request cardiology review for further investigation, medication and follow up
In event of failure:
Continue cardiac monitoring
Contact the cardiology team for assistance
Consider use of further anti-arrhythmic medication if appropriate
Top Tips for DC cardioversion:
ALWAYS REMEMBER TO CHECK THAT SYNC IS ON PRIOR TO DELIVERING THE CARDIOVERSION SHOCK
After one shock some defibrillators will turn off the sync automatically.
ALWAYS ENSURE THAT YOU ARE GOING TO DELIVER A SAFE SHOCK.
Follow the consent procedure carefully. Many hospitals will have specific consent forms for DC cardioversion.
It is worth telling the patient the area where the pads are placed may have some burning or pain after the procedure
