Hands-Only CPR for Out-of-Hospital Cardiac Arrest Gaining Traction, With Good Results

New long-term data support a strategy of chest-compression-only CPR for out-of-hospital cardiac arrest (OHCA) for bystanders who are uncomfortable or untrained in giving rescue breathing. The latest numbers represent an update to earlier Swedish registry data showing that more OHCA victims get CPR when the simplified approach is recommended, although there is plenty of room for further improvement, investigators say.

European guidelines introduced compression-only CPR as an option for bystanders who couldn’t or wouldn’t perform standard CPR involving ventilation in 2005. Then, in 2010, these recommendations became even stronger, coming out with a preference for hands-only CPR when a dispatcher is able to provide assistance.

Between 2000 and 2017, there was a “sixfold higher proportion of patients receiving compression-only CPR and a concomitant almost-doubled rate of CPR before emergency medical services [EMS] arrival over time,” lead author Gabriel Riva, MD (Karolinska Institutet, Stockholm, Sweden), told TCTMD via email. “This very large increase in simplified CPR was surprising to us, especially considering there have never been any public campaigns promoting compression-only CPR in Sweden and training still includes compressions and ventilations.”

Hands-only CPR is easier to perform than standard CPR and may help overcome the reluctance that some bystanders feel, including “fear of being incapable, causing harm, and infection,” Riva and colleagues suggest in their paper.

The new report, published online today in Circulation, confirms similar trends the researchers observed in an earlier analysis of data ending in 2014.

CPR in Any Form Improves Survival

For the study, Riva et al analyzed all 30,445 bystander-witnessed OHCA cases that were reported to the Swedish Register for Cardiopulmonary Resuscitation between 2000 and 2017. Data were divided into three periods to reflect shifts in guideline recommendations: 2000-2005, 2006-2010, and 2011-2017.

Individuals who didn’t receive CPR prior to the arrival of EMS tended to be older and were more likely to be female and to have experienced OHCA at home than were those who received either standard or compression-only CPR. They also were less likely to have cardiac etiology and ventricular tachycardia/ventricular fibrillation as the initial rhythm.

Median EMS response time differed significantly among groups, from 7 minutes for no CPR to 8 minutes and 10 minutes for compression-only and standard CPR, respectively. Moreover, medically educated bystanders were more prevalent in the standard CPR group than in the compression-only group (25.1% vs 15.3%).

Over time, the proportion of patients who received CPR before EMS arrived rose (from 40.8% to 58.8% to 68.2%), as did the percentage given compression-only CPR (from 5.4% to 14.0% to 30.1%). Hands-only CPR grew more prevalent among bystanders with medical training and among those who lacked that expertise.

Survival at 30 days improved across the three periods no matter whether received CPR or what type of CPR was performed. These patterns were consistent irrespective of whether the OHCA was of cardiac or noncardiac etiology, the patient’s age, or where the event occurred. Overall, women were less likely to live through their OHCA, with a less pronounced link between CPR and survival.

Thirty-Day Survival After Bystander-Witnessed OHCA

That survival improved for all three groups “indicates that several mechanisms other than higher rates of CPR before EMS arrival have contributed,” Riva and colleagues suggest, pointing to “faster recognition of OHCA at dispatch centers, availability of public automated external defibrillators, more advanced/aggressive treatments and updated CPR algorithms for EMS, and more aggressive in-hospital treatment such as fast coronary intervention and improvements in postcardiac arrest care.”

Yet, compared with no CPR, 30-day survival was approximately doubled for patients given standard CPR (adjusted OR 2.6; 95% CI 2.4-2.9) or hands-only CPR (adjusted OR 2.0; 95% CI 1.8-2.3). The likelihood of survival was slightly but significantly higher for standard versus compression-only CPR (adjusted OR 1.2; 95% CI 1.1-1.4). 

“These findings support continuous endorsement of compression-only CPR as an option in future CPR guidelines because it is associated with higher CPR rates and overall survival in out-of-hospital cardiac arrest,” the investigators conclude. “Randomized controlled trials are needed to answer the question of whether or not CPR with compression and ventilation is superior to compression-only CPR in cases in which the bystanders have had previous CPR training.” Riva told TCTMD that such a trial is now ongoing in Sweden. 

Sobering, however, is that even by the end of the study period, “one-third of all witnessed OHCA did still not receive any intervention before emergency medical services arrival in the last time period,” he added. “This leaves a large room for improvement (especially for OHCA occurring in homes).”