59 y/o M presents to the cardiac room after cardiac arrest. EMS reports a downtime of 5 minutes with immediate bystander CPR. The initial rhythm was vifb that responded to two EMS shocks and CPR. The patient arrived with ROSC. Soon after the patient goes back into VF. You try everything in the books-continuous compressions, repeated shocks at 360J, all the drugs, but nothing breaks it. Twenty minutes have passed. Is there anything that can be tried or should you call it?
Double-sequential defibrillation has been around in the EP literature since the 1990s. The concept involves taking two defibrillators, attaching both sets of pads, and shocking at 360J simultaneously. Refractory (or shock resistant) VF is noted to occur in up to 0.1% of EP studies. In a series of 3,000 consecutive patients with VF, Hoch, et al noted that 5 were refractory, but all 5 responded to double shocks.
The idea has been gaining traction in the EMS community in the US as well as internationally. A Wake County EMS, in North Carolina study described 10 patients that underwent DSED at for refractory VF in out-of-hospital cardiac arrest. VF broke after DSED in 7 cases (70%). While its clear more data is needed to show mortality benefit, its something to consider when all else has failed.
Hoch DH, Batsford WP, Greenberg SM, et al. Double sequential external shocks for refractory ventricular fibrillation. J Am Coll Cardiol. 1994 Apr;23(5):1141-5.
Cabañas JG, Myers JB, Williams JG, De Maio VJ, Bachman MW. Double Sequential External Defibrillation in Out-of-Hospital Refractory Ventricular Fibrillation: A Report of Ten Cases. Prehosp Emerg Care. 2015 January-March;19(1):126-130.