The best approach to CPR for a bystander who wants to save the life of a victim of sudden cardiac arrest is to pump the chest and skip the mouth-to-mouth, a Japanese study suggests.

Cardiopulmonary resuscitation is a first aid procedure for an unconscious person whose breathing and/or pulse have stopped.

Acting quickly and giving efficient chest compressions are key to saving someone's life.
(CBC)

CPR is traditionally defined as a combination of chest compressions and ventilation, also known as mouth-to-mouth resuscitation, with the aim of protecting the heart and brain until the heart resumes pumping in a normal rhythm.

Ken Nagao of Surugadai Nihon University Hospital in Tokyo and colleagues compared how well more than 4,000 adults fared after receiving traditional CPR, the chest-compressions only approach, or no CPR at all until paramedics arrived.

Patients who received only chest compressions had less brain damage than those who got compressions and breaths, the team reported in Saturday's issue of the medical journal The Lancet. Not surprisingly, patients who had no CPR had the poorest outcomes.

Rescue breathing paradox

The researchers suspect breaths may be detrimental if there is only one person performing CPR, because the mouth-to-mouth breathing takes precious time away from chest compressions that bring blood to the heart and brain.

"For cardiac arrest, the term 'rescue breathing' is actually a paradox," said Dr. Gordon Ewy of the University of Arizona, where the chest compression only approach was developed. "We now know that not only is it not helpful, but it's often harmful."

Survival rates are higher when blood has less oxygen but is circulated well through the body by compressions, said Ewy, who wrote a journal commentary accompanying the study.

It's because breaths greatly reduce the efficiency of compressions, and it may take several compressions to catch back up, said Dr. Martin Green, a cardiologist at the Ottawa Heart Institute.

Updating guidelines

CPR instructors with the Heart and Stroke Foundation of Canada now teach people to give 30 chest compressions and then two breaths. The formula is based on the foundation's last update of its CPR guideline two years ago, an update which placed less emphasis on mouth-to-mouth.

The Heart and Stroke Foundation of Canada will not change its guidelines on mouth-to-mouth resuscitation unless more research is done, said Judy Black.
(CBC)

More studies are needed before making the change recommended by the Japanese team, said Judy Black of the Heart and Stroke Foundation in Halifax.

The Canadian Red Cross also has no plans to change its CPR training courses, the organization said Friday. 

It's hoped that the new approach would encourage more people to step in to save a life, since some balk at performing mouth-to-mouth on a stranger.

But the traditional approach of compressions plus ventilation is still recommended for drowning and drug overdoses, and, in all cases, acting quickly is key.