From the Boston Globe:
The association’s rules, the first update since less significant revisions five years ago, aim to make CPR easier to administer — and to establish a more consistent flow of blood to the heart and brain in the minutes after a heart attack.
The guidelines represent the work of 380 international heart specialists who reviewed thousands of medical studies on cardiac arrest and resuscitation.
The biggest shift involves changing the ratio between heart compressions and mouth-to-mouth resuscitation.
Old guidelines called for rescuers to pump the chest 15 times and then blow into the mouth of the victim twice.
The new recommendations call for 30 chest compressions for every two breaths.
But the guidelines state that in the case of 911 calls placed by CPR novices, it is acceptable for emergency operators to provide instructions for chest compressions only.