The chances of surviving cardiac arrest with good brain function are better when bystanders focus CPR efforts on chest compression without mouth-to-mouth rescue breathing, a nationwide Japanese study affirmed.
When bystanders performed chest compression-only CPR and used a public-access defibrillator, 40.7% of out-of-hospital cases survived at least a month without needing assistance in daily living, Taku Iwami, MD, PhD, of the Kyoto University Health Service in Kyoto, Japan, and colleagues found.
That rate was a third higher than with conventional CPR group and a defibrillator shock, at 32.9%, the group reported online inCirculation: Journal of the American Heart Association.
“This is one of the highest survival rates with neurologically-favorable outcomes reported and should be the target survival after out-of-hospital cardiac arrest,” they noted.
Chest compressions alternating with rescue breathing remains the standard for trained rescuers, but recommendations for untrained bystanders switched in 2010 to only chest compressions regardless of emergency dispatch assistance.
The reason is that “rescue breathing is so difficult to perform that it can interrupt chest compressions,” which animal and clinical studies have linked to survival, Iwami’s group explained.
The hands-only technique may be more effective than conventional CPR in the early phase of sudden cardiac arrest, which may be all that is needed if an automated external defibrillator (AED) is available nearby, they added.
These findings would likely generalize to other countries, like the U.S., where AEDs are widespread, according to a statement from the American Heart Association.
“Across the U.S., too many people are dying from sudden cardiac arrest because family members and friends of the victim are unsure how to help. This study confirms that hands-only CPR is highly effective. Plus it’s easy to do,” Michael Sayre, MD, of the University of Washington in Seattle, said in the release as a spokesperson for the AHA.
The study analyzed all consecutive out-of-hospital cardiac arrests of presumed cardiac origin that were witnessed and received CPR and AED shocks as recorded prospectively in the All-Japan Utstein Registry of the Fire and Disaster Management Agency.
The population-based registry included 1,376 such cases among the total 547,153 confirmed out-of-hospital cardiac arrests that occurred in Japan over a 5-year period, basing CPR characteristics on bystander interviews with emergency responders on the scene.
In this country where 1.6 million individuals each year get conventional CPR training offered by fire departments and the emergency dispatch gives conventional CPR instructions, chest compression-only CPR accounted for just 34% of cases in the analysis.
That proportion rose over time from just 5% of eligible patients in 2005 when the registry started to 44% in 2009 (P<0.001 for trend).
But outcomes were better after chest compression-only CPR than when it involved rescue breathing for several key endpoints:
- Prehospital return of spontaneous circulation (50% versus 40%, P<0.001)
- One-month survival, based on follow-up by emergency responders (46% versus 40%, P=0.018)
- Survival to at least 1 month with no more than moderate cerebral disability (41% versus 33%,P=0.003)
The odds of 1-month survival with favorable neurological outcomes remained 33% more likely (95% CI 1.03 to 1.70) for the hands-only group after adjustment for age, sex, time from collapse to public-access AED shock or initiation of CPR by bystanders, and year.
The study couldn’t determine the quality of bystander CPR or what biases might have led some to do chest compressions only, since only conventional CPR was taught in Japan at the time.
Nor could the results be extrapolated to the 97% of witnessed out-of-hospital cardiac arrests with CPR by bystanders that didn’t get shocked by public-access AEDs.
Nevertheless, the superiority of hands-only CPR in the study “strongly suggests the need for implementation of public-access defibrillation programs with attempts to increase the number of lay rescuers who can at least perform chest compression CPR and use an AED,” the researchers concluded.
Conventional CPR with rescue breathing is still recommended for children, since their cardiac arrests are less likely to be of cardiac origins, so a dual training program may be warranted.
Iwami’s group proposed chest compression-only training as standard for most people and conventional CPR training as an option for medical professionals, lifeguards, school teachers, and families with children.
They pointed to a successful public campaign in Arizona that “has consistently and carefully advocated conventional CPR for suspected noncardiac and pediatric arrests and successfully demonstrated that most pediatric out-of-hospital cardiac arrest patients had received conventional CPR.”
http://www.medpagetoday.com/Cardiology/Arrhythmias/36380
