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Friday, August 2, 2013

CPR Details

Please go to and fill in the requested information. We need to understand the limits of chest compression capacity in more detail before we set about fixing the problem.

Every five years, ILCOR & AHA issue their updated CPR Guidelines. In 2005, the guidelines called for two rescue breaths, followed by cycles of thirty compressions & two rescue breaths. The compressions had to be between 1.5 and 2.0 inches deep (~38 mm to 50 mm) and delivered at a rate of 100 per minute.

When those guidelines were put in place, it was as if someone had dropped a boulder into a pond: Instructors had to demonstrate that they could perform five cycles of "30 & 2" about every two minutes. A large number of CPR instructors were unable to renew their Instructor certificates.

Then in 2010, the new guidelines called for a rate between 100 & 120 (AHA) or a rate greater than 100 (ILCOR). The initial two rescue breaths were gone, but the compression depth went to "at least two inches" for adults. With the passage of time the guidelines - established to ensure that the defined therapy meets the needs of the victim - keep on demanding more and more from those performing CPR. ...and things get messier when you realize that not all human chests have the same stiffness. It takes anywhere between forty and several hundred pounds to perform two inch deep compressions on a human, depending upon the characteristics of the specific human involved.

I must stress at the outset that "any CPR is better than no CPR." Please do not use anything in this note as an excuse to not even try!

Performing Guideline-Compliant Chest Compressions ("GC3's") requires two things: First, one must be able to compress the chest a full two inches, and second, it requires that one do so for a specified period of time: two minutes, if you are an EMT, Paramedic, Nurse, or Physician; Until someone else takes over, if you are a bystander. In the case of the bystander, this can mean anything from a few minutes to nearly twenty minutes. This is a challenge we'll discuss in a future post.

There are two forces at work when one tries to compress a chest: There is a force that comes from a portion of the rescuer's weight, and there is a component that comes from the deceleration of the rescuer's hands as they reach the bottom of the compression. These two forces add to form the total compressive force. SLICC is currently gathering data in an effort to better understand the magnitude of the problem.

You can help by going to and answering a few questions. Your help will be much appreciated.

The results will be reported here when they are available.

Thank you.