The Stats:

  • 350,000 out-of hospital cardiac arrests (OHCA)/209,000 in hospital cardiac arrests (IHCA) each year (2016)
  • Majority of cases have a primary cardiac etiology with vfib as presenting rhythm

So SHOCK IT!…..Survival Rate: OHCA 12%/IHCA 24.8

Enters Dual Sequential Defibrillation (DSD)

  • Research previously conducted in animals. In 1986 Chang et al showed that DSD resulted in lower peak voltages and lower energy required to terminate vfib, their findings indicated that increased body habitus required more energy to terminate vfib
  • Zhang et al (2002) also showed similar findings in pigs

Now onto the humans…

  • Merlin et al 2016 showed in a recent case series of 7 patients:
    • Mean time of resuscitation before DSD=34 minutes
    • Mean shocks delivered before DSD=5
    • Mean DSD shocks=2
    • Jules: monophasic 360J x2
    • 3/7 patients survived to discharge w/ ok neurologic outcome CPC scores ranged from 1-3 (1 being independent to 3 dependent)
    • Why it worked?
      • Increasing the number of vectors may capture more myocardium
      • Sequential shocks may result in longer duration of defibrillation
    • Next will look at this in 60 patients

Additional studies:

Author Type of Research Outcomes
1. Lybeck et al. 2015 Case Report Pt survived after DSD on 8th attempt
2. Cabanas et al. 2014 Case Series ROSC in 7 of 10 patients. No Survivors
3. Hoch et al. 1994 Subgroup Analysis 5 patients converted in EP lab after refractory VF. All survived
4. Leacock 20147 Case Report Pt survived after DSD on 5th attempt (400J)
5. Gerstein et al. 2014 Case Report Pt had ROSC after 400J with DSD and failed single multiple defibs. Pt did not survive



  1. Place 2nd set of pads in Anterolateral or Anteroposterior position, may be adjacent to first set of pads but not touching!
  2. Charge both monitors (360J for monophasic and 200J for biphasic)
  3. CLEAR!
  4. Simultaneously press both shock buttons
  5. Resume CPR



  1. DSD may work…
  2. Need 2 sets of pads! Place in AP or AL position
  3. Can use monophasic or biphasic defibrillators no proven standard of Jules
  4. May work because: (1) captures more of the myocardium with increase in vectors (2) delivers more energy through larger body habituses, (3) increased duration of defibrillation…but not certain
  5. We need more studies


Johnston et al 2016 Case Report: For the romantics

28yo F presents with out of hospital cardiac arrest as witnessed by husband. Husband calls 911 and begins CPR while awaiting for EMS. 6 minutes later EMS arrives and begins ACLS. Within first 15 minutes patient receives 6 shocks, Epi, Amio and then last but not least double sequential defibrillation and achieves ROSC 2 minutes later! EKG is STEMI negative. Patient taken to hospital later diagnosed with long QT syndrome, gets an ICD, and leaves hospital with significant level of independent function and able to return to her 16mo old daughter!! 

Shoutout to Doug for posting this topic for a previous TR Pearl and bringing it to my attention!

The sources:

July 2024