This article is more than 5 years old. Information may no longer be current.
CPR before EMS arrival beneficial; cellphone dispatch of laypersons effective
CPR performed before the arrival of emergency medical services was associated with better survival rates, and a mobile-phone dispatch system improved rates of bystander-initiated CPR, according to the results of two studies published in The New England Journal of Medicine.
Early CPR improved survival rate
In one study, researchers analyzed 30,381 out-of-hospital cardiac arrests that occurred in Sweden between 1990 and 2011 to determine whether CPR was performed before EMS arrival and whether early CPR was associated with a higher survival rate.
Ingela Hasselqvist-Ax, RN, and colleagues found that CPR was performed before EMS arrival 51.1% of the time. The 30-day survival rate for those who had CPR performed prior to EMS arrival was 10.5% vs. 4% for those who did not (P < .001).
Hasselqvist-Ax, from the Center for Resuscitation Science, Karolinska Institutet, Solna, Sweden, and colleagues determined that after adjustment for a propensity score based on age, sex, location and cause of cardiac arrest, initial cardiac rhythm, EMS response time, time between patient collapse and the call for EMS and year of event, CPR performed before EMS arrival was associated with an increased 30-day survival rate (OR = 2.15; 95% CI, 1.88-2.45). This correlation was consistent during the study period, they found.
Among the 23,931 patients for whom time between collapse and start of CPR was known, survival rates were better the quicker from time of collapse to start of CPR (0 to 3 minutes, 15.6%; 4 to 8 minutes, 8.7%; 9 to 14 minutes, 4%; more than 14 minutes, 0.9%; P <.001), and the trend was consistent across all subgroups, according to the researchers.
Mobile-phone dispatch of laypersons
The researchers also conducted a randomized controlled trial of a mobile-phone positioning system activated when ambulance, fire and police services were dispatched in Stockholm to locate volunteers trained in CPR within 500 m of patients with out-of-hospital cardiac arrest.
Volunteers (n = 9,828) were dispatched (intervention group) or not dispatched (control group). The primary outcome was bystander-initiated CPR prior to arrival of ambulance, fire and police services.
During the study period between April 2012 and December 2013, the mobile-phone positioning system was activated for 667 out-of-hospital cardiac arrests; 46% in the intervention group and 54% in the control group.
Mattias Ringh, MD, from the Center for Resuscitation Science at Karolinska Institutet, and colleagues found that the rate of bystander-initiated CPR was 62% in the intervention group vs. 48% in the control group (absolute difference, 14 percentage points; 95% CI, 6-21). – by Erik Swain
Disclosure: The researchers report no relevant financial disclosures.
Perspective
Back to Top
The study by Hasselqvist-Ax and colleagues reconfirms our existing evidence that bystander CPR can double the survival rate after out-of-hospital cardiac arrest. A newer point of emphasis is the importance of starting CPR early. When CPR was started within 0 to 3 minutes of cardiac arrest onset there was a 15.6% survival rate. A delay in starting CPR of 4 to 8 minutes was associated with a 50% decrease in survival to 8.7%. Survival was cut in half again to 4% when CPR was initiated between 9 and 14 minutes after cardiac arrest, and survival was rare when CPR was initiated more than 14 minutes after cardiac arrest onset. That’s an important consideration in bystander CPR. Right now, we emphasize and measure the incidence of bystander CPR, but this study helps us amplify the importance of how quickly someone responds, and how important it is to start bystander CPR as soon as possible. It also emphasizes the importance of measuring this interval for continuous quality improvement in out-of-hospital systems of care.
The study by Ringh and colleagues demonstrated improved bystander CPR rates when mobile-phone messaging was used to dispatch CPR-trained laypeople to the scene of a cardiac arrest. This well-controlled study reported an absolute 14% increase in the percent of patients that received bystander CPR. The concept of having trained laypeople as part of an entire system of care is an important model that we should embrace. Our approach to out-of-hospital cardiac arrest is unique in that the initial diagnosis and treatment needs to be performed by a layperson bystander. Therefore, bringing the lay providers into the system of care for out-of-hospital cardiac arrest is critical. We have to think more broadly and innovatively about how we can do that. Mobile-phone dispatch is a good start, and there will be lots of innovative ways for this to move forward. However, it will take some time for widespread implementation in the United States. The organization, structure and funding of medical dispatch is quite variable across the country. Many systems do not have the capabilities of doing GPS localization or sending text messages. But data showing increasing bystander CPR rates and improved outcomes will help drive implementation.
Hands-only CPR is a major advance in the concept of bringing the minimally trained or untrained provider into the system. Having training in CPR helps you be confident in responding, but we know that even people who haven’t had formal training can have an impact by initiating hands-only CPR. If you broaden the scope to those who haven’t had training, you can broaden the potential responders to any cardiac arrest. The goal of the hands-only CPR initiative is to maximize the number of people who can respond to out-of-hospital cardiac arrest. Figuring out ways to encourage the public to act is something we need to continue to support and emphasize.