Having just read [“All Charged Up & No Place To Go,” July 2017], and being the chair of the medical control board (MCB) for one of the larger EMS systems in the country, I have to take issue with item four in the article.
We have implemented dual defibrillation protocols within our EMS service, but only after getting input from the manufacturer, and engineers, of our cardiac monitor devices. They warned that “dual-shock” could damage the devices and would void the warranty. However, “dual-sequential” shocks would not. That means that instead of pushing both shock buttons simultaneously, we have a one second pause before the second shock button is pushed.
This warranty issue was a huge consideration in our EMS system, as it is with others, and having to replace monitors that have been rendered inoperable by “dual-shock” is not being fiscally responsible to the cities we serve and their citizens.
Having used this technique successfully myself on several patients in my ED, I am a firm believer in its efficacy. However, I wanted to share what our MCB learned when we chose to ask the device manufacturer about this new process.
– Michael S. Smith, MD, FACEP
Dr. Helman Responds
Thanks for your comment. You are correct that the warranty does not cover simultaneous dual shocks.
Based on consultation with defibrillation researchers and experts Dr. Sheldon Cheskes and Dr. Paul Dorion, the probability of device damage is actually very small and has never been observed in the double defib studies they have done for atrial fibrillation and ventricular fibrillation (VF). That being said, for some manufacturers at least, there is a reasonable small risk, so they are concerned about warranty.
Drs. Cheskes, Dorion, and I are also skeptical about sequential (one second separation) shocks being different than a second shock 15 or 30 sec later. For double difib to be effective, the shocks must be as close as possible together without being simultaneous (this is guaranteed by having one person hit shock on both defibs as quickly as possible). A one-second gap is too long.
Of course, we do not know the true answer about simultaneous (where there are data) or sequential (where there is only speculation) being better than a shock for VF two minutes later.
– Anton Helman, MD, CCFP(EM), FCFP