Compression-only CPR Increases Survival in Out-of-Hospital Cardiac Arrest Patients

Over an 18-year period, the rate of bystander cardiopulmonary resuscitation (CPR) before emergency medical services (EMS) arrival nearly doubled, and rate of compression-only (CO-CPR) increased six-fold, and the chance of survival doubled for using any form of CPR compared to no CPR, according to a review published in Circulation.

In this national study, researchers examined data on bystander witnessed out-of-hospital cardiac arrests involving 30,445 patients reported to the Swedish register for CPR in 2000 to 2017. They excluded non-witnessed, EMS-witnessed, and rescue breath-only CPR cases. Patients in the study were categorized as receivers of no CPR (NO-CPR), S-CPR, or CO-CPR prior to EMS arrival. The study’s guideline periods were 2000 to 2005, 2006 to 2010, and 2011 to 2017, and were used for comparisons over time. Moreover, the primary outcome was 30-day survival.

Increase in Compression-only CPR

Results of the review showed the proportions of patients receiving CPR before EMS arrival increased from 40.8% in the first time period to 58.8% in the second period, and to 68.2% in the last period. Also, S-CPR changed from 35.4% to 44.8% to 38.1%, and CO-CPR increased from 5.4% to 14.0% to 30.1%, respectively. Furthermore, 30-day survival increased from 3.9% to 6.0% to 7.1% in the NO-CPR group, from 9.4% to 12.5% to 16.2% in the S-CPR group, and from 8.0% to 11.5% to 14.3% in the CO-CPR group. Overall, for all time periods combined, the adjusted odds ratio for 30-day survival was 2.6 (95% CI, 2.4 to 2.9) for S-CPR and 2.0 (95% CI, 1.8 to 2.3) for CO-CPR juxtaposed with NO-CPR. S-CPR was indicated as superior to CO-CPR (adjusted OR=1.2; 95% CI, 1.1 to 1.4).

Bystander Role

“We found a significantly higher CPR rate for each year, which was associated with higher rates of compression-only CPR,” said Gabriel Riva, MD, a PhD student at the Karolinska Institutet in Stockholm, Sweden, and lead author, in a press release . “Bystanders have an important role in out-of-hospital cardiac arrest. Their actions can be lifesaving.”

“CPR in its simplest form is just chest compressions. Doing only chest compressions doubles the chance of survival, compared to doing nothing,” Dr. Riva continued.

He further noted than an ongoing randomized trial in Sweden is attempting to answer the question of whether CPR with rescue breathing by trained individuals is more effective than hands-only CPR performed by bystanders.

“This is important since CPR performed by bystanders before emergency services arrival is one of the most important factors for surviving an out-of-hospital cardiac arrest. Thus, increasing CPR rates by simplifying the CPR algorithm for bystanders can increase overall survival.”