The Danish AED (automated external defibrillator) registry was established in 2006 with a link to emergency dispatch 112. Still, AEDs were little used and the emergency services decided to adopt a Swedish model where citizens can act as responders to out-of-hospital circulatory arrest (OHCA). The model is supported by the software system Heartrunner. While the initial system used SMS alerts, the system today makes use of the GPS location of the citizen responders and, allowing to alert the citizen responders closest to the OHCA location, is thus more accurate.
In order to implement the Heartrunner system in Denmark, called Hjerteløber in Danish, the emergency services established a collaboration with the foundation TrygFonden. Trygfonden, closely connected to the insurance company Tryg, funds projects that support collaboration between citizens and increase security in the society. TrygFonden has supported the technology development and the implementation of Hjerteløber.
In 2017, a pilot was conducted in Copenhagen and the capital region.The programme was rapidly expanded to the whole country. The scaling in Denmark evolved much faster than expected, thanks to political support that wanted to have one system covering the whole country. It is now a political decision to use a single system in Denmark.
The Hjerteløber app alerts the users close to the OHCA location. The aim is to initiate bystander CPR before the ambulance arrives, thus gaining a few minutes and increasing survival. Time is critical in heart resuscitation. Few minutes mean a lot for the quality of life of the person with heart arrest. It takes 8-10 minutes for an ambulance to come. If citizens close to the incident intervene quickly and do CPR, response time can be shortened, especially in private homes. Critical cases, such as criminal cases, are filtered out or can be cancelled by the dispatch centres.
155 000 people have started using the Hjerteløber app (for a Danish total population of 6M). The average user age is 30-32 yo. Women and men are equally represented. 25% are health professionals. In order to avoid administrative work, CPR course certification course is not required for becoming citizen responders. This choice is grounded in the fact that helping is the most important and that the 112 personnel can guide citizen responders. When signing up, users report if they have a CPR course. Experience shows that people who sign up usually have CPR knowledge. 95% of users took a CPR course in the last of last 2 years. More and more people have knowledge about CPR in Denmark. A CPR course is mandatory when taking the driving license which might explain that many young people have signed to Hjerteløber.
The support of the foundation TrygFonden in the implementation of the solution was and is invaluable. Trygfonden has provided research funds and covered expenses of SW development and integration. They have worked with the marketing of the system and the recruitment of volunteers. Trygfonden sends regularly newsletters to the registered users with information about recent research results and CPR course opportunities.
In 2025, the responsibility of Hjerteløber will be moved to the Danish emergency services and the system will be anchored within the healthcare system. TrygFonden will pursue recruiting citizen responders and pay for the transition.
Note that the Heartrunner system is also used in Sweden. It was first introduced in Sweden but has reached more volunteers in Denmark. The communication strategy in Denmark has shown to be very successful. The experience from the implementation and use in Sweden is not covered here.
Changing common perceptions of the risk of cardiac arrest and responsibility when cardiac arrest occurs is the first step towards recruiting citizen responders. It is important that citizens understand that cardiac arrest can affect everyone, that it is essential to help, that anybody can help, that nobody can do something wrong when doing CPR.
To change people's mindsets requires good stories. It is something that health personal and researchers have not the capacity to do so. Collaboration with an actor that can actively inform people is important. The communication in Denmark was extremely successful. Information is shared though various channels. Marketing is backed up with evidence from research. Five years after launch, everyone in Denmark knows about Hjerteløber.
Civilian first responders should preferably have CPR training. Although not mandatory in Denmark, people who sign up as citizen responders have training. CPR training increases confidence in the ability to provide help.
Health professionals are more inclined to join. This might be exploited during the initial launch of the approach. Knowledge about CPR and AED is important. Making CPR training easily available can contribute to more volunteers. It is important to provide links to web pages where volunteers can see videos and read information.
The implementation of the solution requires a solid infrastructure including software, AEDs and a registry of AEDs. The software has to be integrated with the dispatch centre system. The number of AEDs and the coverage are important. The costs of establishing and maintaining this infrastructure as well as those of promoting the solution are non-negligeable.
The implementation of the system requires good collaboration between health professionals and other stakeholders that can support promotion, increasing AED coverage and research needed to tune the system.
Political support has shown to be speed up the adoption in Denmark. Hjerteløber is now on the National board of health. Funding was given to improve the emergency services and volunteers are seen as a part of the program.
The civilian first responders close to the incident location can provide help quickly before the arrival of the ambulance. The number of responders to be notified and the size of the area should be configured based on experience.
When the program was first launched in Copenhagen and the capital region, the emergency services doubt people would sign up. The solution was anticipated to be better suited for rural areas, where people expect the ambulance arrival to be long and where people know their neighbours. Surprisingly, many people signed up in Copenhagen within a few months.
It should be very easy to sign up and use the app.
No CPR training is required to sign up. Rather videos about CPR and opportunities for training are shared with the volunteers.
The solution needs to be adapted to areas with low socio-economic status and high degree of ethnic diversity. Inhabitants in such areas tend to not use the emergency services. They often call their family first. An intervention is currently going now with teaching what a cardiac arrest is, what CPR is in multiple languages, as well as tracing AEDs.
Research is also currently conducted in Denmark to investigate if there are communities or municipalities with low participation and, for those, to design an approach to reach them.
Following-up the civilian first responders after an incident is important.
At the exception of critical situations, the solution is used when emergency services receive a notification about an OHCA. The system is currently configured so that 20 alerts are sent to the 20 closest potential responders. As time is critical, alerts are sent simultaneously. Experience shows that 50% of the alerted users do not see the alert instantly. Users might, for instance, have set their smartphones in silent mode. Around half part of the users who notice the alert within a few seconds, accept the request. This means that in average 5 users engage in providing help. Sometimes there might be only 1 user. Once, it occurred that there were 14 persons in a flat before ambulance arrival.
A study of suspected OHCAs with alerted citizen responders from September 2017 to August 2018 conducted by researchers at the Copenhagen University Hospital found that one or several citizen responders were on the scene before the ambulance and able to start life-saving interventions in 42% of cardiac arrests during this period. In the group where citizen responders were first on the scene, the researchers show that three times as many patients received defibrillation before the ambulance arrived (21.2% compared with 6.7%).
Research conducted by Astrid Marie Rolin Kragh from the Department of Emergency Medical Services in Copenhagen shows that, beyond stepping in with CPR and AED, citizen responders using Hjerteløber make an invaluable difference for the relatives of the person with cardiac arrest. In a study where 18 489 citizen responders were sent for suspected cardiac arrest, 36% before the ambulance. While 18,5% of the citizen responders gave CPR and 10% per cent put on a defibrillator, 18,6% provided support to the relatives. 14,9 of the citizen responders who arrived after the ambulance stayed at the scene to provide support to relatives.
Therefore, it is important that the citizen responders know that even if they do not participate in the actual resuscitation, they play an important role. They take care of the relatives, reassure them and help contact family who can come and stay with the relatives".
A study from Sweden indicates that citizen responders feel confident after being alerted. People were happy to help other. They felt that they contributed positively to something very important and that they were a part of a system.
Research is needed in order to find the optimal number of persons to alert and the optimal distance so that citizen responders can reach the incident location in a certain time frame. There exist different systems across the world based on a similar approach. All use different activation radius. No one knows what is best.
The pilot in Copenhagen started using a range of 1,8 km as was done in Sweden. 1,8 km is too far in Copenhagen. Due to the traffic, it is impossible to reach the scene quickly from a 1,8 km distance. The distance should only be a few hundred meters. However, in the countryside, 1,8 km is sometimes less than the distance to the next neighbour. It is too short. The range may need to be 10 kilometres. Currently, the maximum radius is set to 5 km, but only the closest 20 citizen responders are alerted.
With the goal to conduct solid research and improve the system, the emergency services wished to collect and store data about the usage of the app. The GDPR regulations are challenging. One should clearly explain the conditions about what/how location is used for the users that sign up, as well as how data are used for research.
The users experienced frequent software errors when the system was launched. For instance, some couldn’t sign in. A Facebook group was established where users can report errors and propose changes. For instance, some users wished to improve the map. The emergency services and Trygfonden work closely with SW programmers in Sweden in order to report and prioritize feedback from the citizen responders.
Although 155 000 people have installed the app, not all users are available when an alert occurs. In order to avoid battery drain, GPS tracking on smartphones is normally stopped automatically after a while. Users may not be aware of it, and thus may not receive alerts when they are close to an OHCA scene.
In some cases, a door code is needed to enter a building. The dispatch centre should be able to send an update with the door code through the app.
In some cases, people couldn't find the building or wrong addresses were given.