Picture: Chest compression 
Apparently in first aid courses the
emphasis should be laid on chest
compressions; © PixelQuelle.de

The study reported in The Lancet analysed the outcomes of 4,068 cases of witnessed collapse of adults in the Kanto area in Japan. "For cardiac arrest, the term ‘rescue breathing’ is actually a paradox," says Gordon A. Ewy, MD, director of the Sarver Heart Center at The University of Arizona in Tucson. "We now know that not only is it not helpful, but it’s often harmful."

Studies showed that because current cardiopulmonary resuscitation (CPR) guidelines call for mouth-to-mouth ventilations, the majority of people would not perform CPR on a stranger, partly out of fear of contracting diseases. Even if bystanders are willing to perform mouth-to-mouth ventilation, it takes too much time away from chest compressions, which have to be continuous to improve the chance of survival.

"We have found that the survival rate is higher even when the blood has less oxygen content, but is moved through the body by continuous chest compressions, than when the blood contains a lot of oxygen but is not circulated well because chest compressions are interrupted for mouth-to-mouth ventilations," Ewy says.

Among these patients, the researchers found the percentage surviving with a favourable neurological outcome to be 19.4 percent if bystanders administered chest compressions without mouth-to-mouth ventilations. In contrast, the favourable neurological survival rate in those who received chest compressions and mouth-to-mouth breathing was only 11.2 percent.

While the study provides unequivocal evidence that chest-compression-only resuscitation boosts survival rates for out-of-hospital cardiac arrest, Ewy points out that, for respiratory arrest such as near-drowning, drug overdose or choking, guideline CPR consisting of 2 breaths after every 30 chest compressions is still the appropriate method.

MEDICA.de; Source: University of Arizona