Posted by Bob Trenkamp on 07/13/2012

My family all know what to do when they witness a sudden cardiac arrest: if the victim is non-responsive and not breathing normally, they call 911, they get the victim on a hard, flat surface with the head tilted back, and they begin compressing the chest at least two inches deep at a rate between 100 and 120 compressions per minute, and they defibrillate the victim promptly if there is an AED available and immediately resume compressions. If there is no AED available, they don't stop compressions until someone else takes over.

But there's a problem with this: if they perform chest compressions the way they would be taught in an AHA or ARC or just about any other course, they won't be able to sustain the target compression rate and depth until the ambulance gets there. Most people cannot provide adequate chest compressions for three minutes. The longest I've seen is an Army Ranger Medic who lasted a little more than nine minutes.

So how long do you have to perform chest compressions in a real-world situation? and how can you overcome the three minute wall?

It all depends upon where you have the arrest and how many people are able to share the chest compression task. If you have your arrest on a farm, your chance of surviving are close to zero, probably because a long period of time elapses between the time of the arrest and the arrival of the ambulance.

In a suburban or metropolitan setting, the shortest time between the time of the arrest and the arrival of the ambulance crew at the victim's side is likely to be ten to twelve minutes. Remember that when you see the arrest, you have to figure out what's happening; you have to call 911; you have to tell the 911 operator where you are, what's wrong, what you're doing about it, and what you need; the 911 operator needs to either relay the information to the ambulance dispatcher or has to figure out which ambulance will be dispatched and contact them; and the crew on the ambulance has to get in route to the scene. By the time the wheels are rolling, two to four minutes are likely to have elapsed since the time of the arrest. It is not unusual for five to eight minutes to elapse from the time the ambulance is rolling to the time of patient contact. Do the math. Act out all the steps. it's likely that if you are alone with the victim, the victim's odds of getting out of the hospital with major brain function intact will hinge or your ability to perform adequate chest compressions for ten to twelve minutes.

My wife can perform adequate chest compressions for more than ten minutes.(That's when we stopped timing - she was still going strong at the ten minute mark.) She was using the heel of her foot at the "CPR point", standing alongside the victim, facing the manikin's feet.

Unfortunately, that's not what you learn in most CPR classes.

SLICC's current class video teaches the traditional method but also teaches the "with your heel" method. It can be downloaded from - just click on "for past trainees" in the left-hand column. It's a large file. Clicking on it multiple times will simply lengthen the time it takes to download it. SLICC's next class video will feature the "heel" method, with a small segment covering the traditional method.