How and why to do chest compression-only CPR for heart attacks

Obviously the best way to treat a heart attack is to prevent it (once it happens the odds are not good). But if you are a layperson responding to a heart attack away from a hospital and emergency personnel, a paper just published in JAMA (the Journal of the American Medical Association) offers more evidence that chest compression-only CPR (without rescue breathing) is the best thing to do. The authors set out to:

"...investigate the survival of patients with out-of-hospital cardiac arrest using compression-only CPR (COCPR) compared with conventional CPR."

4415 subjects who endured an out-of-hospital cardiac arrest of cardiac etiology met their inclusion criteria. 2900 received no CPR, 666 got conventional CPR, and 849 received COCPR. The data are impressive:

"Rates of survival to hospital discharge were 5.2% for the no bystander CPR group, 7.8% for conventional CPR, and 13.3% for COCPR."

Moreover, the adjusted odds ratio for survival showed that while there was not much difference at all between conventional CPR and no CPR at all, COCPR increased the odds for survival by 60%. Interestingly...

"From 2005 to 2009, lay rescuer CPR increased from 28.2% to 39.9%; the proportion of CPR that was COCPR increased from 19.6% to 75.9%. Overall survival increased from 3.7% to 9.8%."

Perhaps you can help spread the word summarized in their conclusion:

"Among patients with out-of-hospital cardiac arrest, layperson compression-only CPR was associated with increased survival compared with conventional CPR and no bystander CPR in this setting with public endorsement of chest compression–only CPR."