Posted by Bob Trenkamp on 01/30/2011

and it appears that many people are taking it.
The wonderful piece in the New England Journal of Medicine a few days ago makes the point that the heart rhythms "shockable" by an AED (ventricular fibrillation and pulseless ventricular tachycardia) are more commonly observed in public places than in the home.
That doesn't mean that more people who arrest in public are more likely to have those rhythms. It means that BY THE TIME SOMEONE GETS A DEVICE LIKE AN AED OR A DEFIBRILLATOR ONTO A CARDIAC ARREST VICTIM, MORE PEOPLE IN PUBLIC PLACES ARE IN A SHOCKABLE RHYTHM THAN ARE PEOPLE AT HOME. THIS IS BECAUSE IT TAKES LONGER TO GET AN AED OR A DEFIBRILLATOR ONTO A PERSON WHO ARRESTS AT HOME..
Some heart rhythms go directly from a normal rhythm to ventricular fibrillation, and some rhythms get there by way of torsades de pointes. In fact, late torsades is often difficult to distinguish from ventricular fibrillation.  But eventually, both ventricular fibrillation and pulseless ventricular tachycardia will both resolve to asystole, unless resuscitative efforts are successful. Asystole is not a shockable rhythm. Thus, if it takes longer for a defibrillator or AED to get to a victim at home than it does to get one to a victim in a public place, it stands to reason that more victims will still be in a shockable rhythm in a public place than at home.
The paper concludes that the data argue for more public access AED's ("PAD's"), as indeed it does. The argument draws it's strength from the observation that we could be saving a lot more lives if there were a lot more PAD's deployed. What the paper doesn't argue for is the availability of an AED that could realistically be placed in a majority of homes. This product is currently made of "unobtanium" because AEDs cost anywhere from the high hundreds of dollars into the low thousands of dollars. If there were a $250 home AED, there is reason to believe that the number of homes with AEDs would soar.  And it that happened, we would see AED's applied to the arrest victim at home faster than in public, and the presenting rhythm would be "shockable" more often at home than in public.
Learn Bystander CPR, and teach others. There is a free class video at www.slicc.org/ClassVideo/
Bob