Denmark’s Community First Responder System for OHCA Is Underused

A community first responder (CFR) system in Denmark—called Heartrunner—was activated by emergency medical services (EMS) call takers in only 57.5% of eligible out-of-hospital cardiac arrest (OHCA) cases in the first 5-plus years after its implementation, a study published online recently in JACC shows.

The activation rate varied widely from 13% to 100% across call takers and was not consistently used across patient groups. In particular, females younger than 20 years or older than 65 years were less likely than similarly aged males to have the CFR system activated, researchers led by Persia Shahriari, MD (Copenhagen University Hospital and Emergency Medical Services Copenhagen, Ballerup, Denmark), report.

“As CFR systems become more embedded in national EMS strategies, this study offers a critical lesson: deployment alone is not enough,” they write in the new paper. “Realizing the lifesaving potential of CFR systems will require not only technological integration but also standardized protocols, decision support tools, and feedback mechanisms to reduce unwarranted variation and ensure equitable activation.”

CFR systems alert community volunteers about nearby OHCAs so they can aid in CPR and defibrillation before EMS arrives. Many have been implemented around the world, including PulsePoint Respond in the United States and Canada, said Shahriari. “But there’s very limited information about how these systems actually perform in terms of how much they are being used,” she told TCTMD. “You can design a system to be extremely good, but if you don’t activate it as much as it should have been activated, then you cannot improve cardiac arrest outcomes.”

Most CFR systems require manual activation on the part of the call taker. That includes the Heartrunner system that was implemented in Denmark in 2017. In the current study, Shahriari et al examined its use in the Capital Region of Denmark, home to about 1.91 million inhabitants, between September 2017 and December 2023 to identify areas for improvement.

The analysis used data from the Danish Cardiac Arrest Registry and Prehospital Patient Files to identify OHCA cases that were eligible for CFR system activation. After exclusion of those caused by suicide, drowning, drug overdose, or trauma, those occurring in nursing homes or rehabilitation centers, and those not recognized as cardiac arrest by call takers, there were 4,320 eligible patients with OHCA (median age 73 years; 63.7% male). The Heartrunner system was activated for 2,486.

Activation rates were highest (over 60%) for patients ages 51 to 80 years. The likelihood of activation also was greater when the arrest occurred in a private home versus a public area (risk ratio [RR] 1.53; 95% CI 1.41-1.66), when there was an EMS response time of at least 10 versus less than 4 minutes (RR 1.27; 95% CI 1.13-1.44), and when the arrest occurred at night versus the morning in a private home (RR 1.10; 95% CI 1.03-1.19).

The CFR system was less likely to be used for female versus male patients in the following age groups:

• < 21 years (RR 0.25; 95% CI 0.02-0.95)
• 66-80 years (RR 0.88; 95% CI 0.81-0.96)
• > 80 years (RR 0.77; 95% CI 0.68-0.86)

Shahriari speculated that the lower use in female patients could be due to them being more likely to have nonspecific symptoms, leading to delayed recognition of cardiac arrest. Or it could be, she said, that activation is more likely for men when the initial call comes from a woman, because the EMS call takers perceive women as having more difficulty moving a male victim into a position where CPR can be started.

In addition to the wide variation across EMS call takers in how often they activated the CFR system, there was also generally declining use over time (P < 0.001)—the system was activated in 76.1% of eligible cases in 2017 and 57.6% in 2023.

You can design a system to be extremely good, but if you don’t activate it as much as it should have been activated, then you cannot improve cardiac arrest outcomes. Persia Shahriari

Though there were slightly higher rates of a return to spontaneous circulation, survival to hospital admission, and 30-day survival for OHCA cases in which the CFR system was activated, the differences were not statistically significant. The investigators note that the analysis of clinical outcomes spanned only September 2017 to May 2019 because of the launch of the HeartRunner Trial, with a low number of community volunteers and response times that were only slightly shorter than EMS response times during this early implementation period.

To help minimize variation in and improve overall use of CFR systems, “I believe you need to evaluate continuously how much the call takers use the system,” Shahriari said. “And I think you need to do that maybe a couple of times every year to ensure that you have a more standardized activation between call takers.”

Moreover, “you need to make it technically easy for call takers to activate the system, especially if you have manual activation,” as with the Heartrunner system,” she said. “The button for activation should be visible and easy to get to. And then I think that you should always get feedback from the call takers because they’re the ones who are using the system.”

In their paper, the investigators also say that automated system activation, as employed by PulsePoint Respond and other CFR systems like GoodSAM in the United Kingdom and Australia and EVapp in Belgium, could be a solution.

Overall, the major take-home message from this research, Shahriari said, is that “when you implement a system, you must always try to monitor it and evaluate it after the implementation process.”