|
Cardiopulmonary resuscitation is a first aid procedure for an unconscious person whose breathing and/or pulse have stopped.
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 now teach people to give 30 chest compressions and
then two breaths, based on when the Heart and Stroke Foundation of
Canada last updated its CPR guidelines two years ago, an update which
placed less emphasis on mouth-to-mouth.
The foundation updates its guidelines every five years, but more
studies are needed before making the change recommended by the Japanese
team, said Judy Black of the Heart and Stroke Foundation in Halifax.
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.
Source: cbc.ca
|
