Without evidence of benefit, an intervention should not be presumed to be beneficial or safe.

- Rogue Medic

Double simultaneous defibrillators for refractory ventricular fibrillation

It looks as if the next generation of defibrillators will go to 11. This patient received a double dose of defib.

Is 720 joules too much?

If your answer is Yes, please explain how 720 joules is worse than death.

What about 400 joules? Some older mono-phasic defibrillators go to 400 joules, but we might see 400 joule bi-phasic defibrillators.

Until then, there is the possibility of using two defibrillators to deliver shocks at the same time, or milliseconds apart. By the time that this is a relevant treatment, the patient has been down for several shocks and is still in a shockable rhythm, but a supervisor or second medic unit should have arrived with a second defibrillator.


It is important to not put the pads from the same defibrillator next to each other.

The paper describes a patient with a BMI (Body Mass Index) of 40, a STEMI, and an onset of VF (Ventricular Fibrillation) in the presence of EMS.

CPR (being performed by the son when EMS arrived at the ED?), 200J x 3, epi x a bunch, amio x 1 by EMS.

High-quality CPR, a bunch more epi, 200 J x 2, lido x 1, bicarb x 1 (bicarb might have been indicated by the patient’s astrological sign), then the shock at 400 joules.

The patient then regained a palpable pulse and blood pressure. He had another brief episode of ventricular tachycardia that responded to a second defibrillation with 400 J. The patient had a wide QRS rhythm that quickly narrowed into normal sinus.[1]


Maybe the patient was not told about the concerns of some people that too much is too much. If he had been told, he would have remained dead, like a good scenario patient.

Next time he can follow the approved scenario.

Five studies have demonstrated safety in patients receiving 720 J of monophasic energy for cardioversion of atrial fibrillation (17,22–25).[1]


Five papers demonstrate the safety of 720 joules in living patients with atrial fibrillation, but many in EMS will tell us that it is too dangerous to use on dead people after the failure of standard doses of energy.

Lake Sumter EMS has been providing compression-only CPR, even adding 720 joule defibrillation, and they may have the best resuscitation rates in America. The rest of us should consider catching up. I wonder how things have gone for LEMS, since I wrote about them a couple of years ago.[2]


While ROSC (Return Of Spontaneous Circulation) is not the right outcome to use to evaluate a treatment, 70% suggests that we should pay attention to what they are doing in Lake Sumter. 46% ROSC in those who could not get ROSC any other way by EMS.

You can’t be too safe is still a lie.

Also read –

When is a double dose of defibrillation a good idea?


[1] Double simultaneous defibrillators for refractory ventricular fibrillation.
Leacock BW.
J Emerg Med. 2014 Apr;46(4):472-4. doi: 10.1016/j.jemermed.2013.09.022. Epub 2014 Jan 21.
PMID: 24462025 [PubMed – in process]

[2] Optimizing Outcomes in Cardiac Arrest
Mon, 10 Dec 2012
Rogue Medic



  1. The Borg added it to protocols back in January.

  2. Has been in our protocols for sometime now, we are finding it more beneficial sooner than later for obvious reasons, next protocol revision will most likely have it on the 4th shock with the 2nd set of pads placed A/P to cover from a different vector.

  3. Two issues:

    Paul Zoll in his early work established that the adult heart could sustain up to 2000-2500 joules without incurring heart damage ( established via enzymes)

    Second issue what are indivdiuals using as criteria for double defib ? (a) refractory to ? # of SOP defib, (b) refractory VF immediately post defin ( no asytolic period (c) large BWI (d) WTF he probably dead so let’s try it !!!


  1. […] 18 Jul 2014 09:20:04 +0000 by Rogue Medic Leave a Comment   In the comments to Double simultaneous defibrillators for refractory ventricular fibrillation, NCMedic and Ambulance Driver write that they have already begun using variations on double […]