Rather than first opening the airway of someone experiencing an out-of-hospital cardiac arrest, new guidelines call for immediately starting chest compressions. The A-B-C (airway-breathing-compressions) approach to cardiopulmonary resuscitation (CPR) had been in effect for more than 40 years.

The 2010 American Heart Association guidelines were published Oct. 18 in a special supplement to Circulation.

The A-B-C approach requires people to "open a victim's airway by tilting their head back, pinching the nose and breathing into the victim's mouth, and only then giving chest compressions," guideline co-author said Michael Sayre, MD, chairman of the AHA Emergency Cardiovascular Care (ECC) Committee.

"This approach was causing significant delays in starting chest compressions, which are essential for keeping oxygen-rich blood circulating through the body. Changing the sequence from A-B-C to C-A-B for adults and children allows all rescuers to begin chest compressions right away," he said.

Research showed that rescuers who started CPR with opening the airway took 30 critical seconds longer to begin chest compressions than rescuers who began CPR with chest compressions.

The change in the CPR sequence applies to adults, children and infants, but excludes newborns.

The new guidelines also eliminate the "look, listen and feel" algorithm, which was to help bystanders check for normal breath before starting CPR. The guideline committee found the performance of "look, listen and feel" to be inconsistent and time consuming. The new recommendation is to start chest compressions immediately on anyone who is unresponsive and not breathing normally.

Other recommendations, based mainly on research published since the last AHA resuscitation guidelines in 2005, include:

• During CPR, rescuers should give chest compressions a little faster, at a rate of at least 100 times a minute. The old recommendation was a compression rate of "approximately" 100 times per minute.
• Rescuers should push deeper on the chest, compressing at least two inches in adults and children and 1.5 inches in infants. The old guidelines called for compressions approximately 1.5 to two inches.
• Between each compression, rescuers should avoid leaning on the chest to allow it to return to its starting position.
• Rescuers should avoid stopping chest compressions and avoid excessive ventilation.
• All 9-1-1 centers should assertively provide instructions over the telephone to get chest compressions started when cardiac arrest is suspected.

"Despite our success [in treating sudden cardiac arrest victims], the research behind the guidelines is telling us that more people need to do CPR to treat victims of sudden cardiac arrest, and that the quality of CPR matters, whether it's given by a professional or non-professional rescuer," said Ralph Sacco, MD, president of the AHA.

Key guideline recommendations for healthcare professionals include:

• Effective teamwork techniques should be learned and practiced regularly.
• Professional rescuers should use quantitative waveform capnography—the monitoring and measuring of carbon dioxide output—to confirm intubation and monitor CPR quality.
• Therapeutic hypothermia should be part of an overall interdisciplinary system of care after resuscitation from cardiac arrest.
• Atropine is no longer recommended for routine use in managing and treating pulseless electrical activity or asystole.

Additionally, pediatric advanced life support guidelines provide new information about resuscitating infants and children with certain congenital heart diseases and pulmonary hypertension, and emphasize organizing care around two-minute periods of uninterrupted CPR.