The prompt delivery of cardio-pulmonary resuscitation (CPR) and early defibrillation before the arrival of emergency medical services (EMS) in the event of an out-of-hospital cardiac arrest (OHCA) are considered among the most important determinants of survival [1–3]. Bystanders can safely operate automated external defibrillators (AEDs) placed in public locations with high incidence of OHCAs, thus reducing time to first defibrillation and increasing survival [2,4–7]. As a result, recent years have seen a worldwide dissemination of AEDs [4,5,8–10]. However, as most OHCAs occur in private homes and not only in high density population areas, early defibrillation is hampered by availability and effective coverage of stationary AEDs [3,11,12]. Patients in private or rural areas thus continue to depend primarily on EMS and first-response programmes for early defibrillation.

Various first-responder programmes involving for example fire fighters, police officers and/or local lay rescuers have been described [13–19]. Although such programmes have typically been conducted in urban and suburban areas [20], reports from first-responder programmes in rural districts have been encouraging, especially with respect to reducing time-to-arrival at the cardiac arrest site [21,22].

In Denmark, the care of frail and dependent elderly people is widely performed by home care providers travelling by car to visit people in their own homes. This article describes a one-year experimental programme for the provision of first response in OHCA cases by home care providers working in a Danish municipality with mixed urban and rural settlement. After systematic training in performing basic life support including the use of an AED, the providers were dispatched in parallel with conventional EMS to cardiac arrest incidences.

Eighty OHCAs occurred during the one-year study period. While the dispatch of home care providers was a relevant option in 60 cases (Fig 1), the providers were dispatched in 28 cases (47%). For ten of those dispatches (36%), a home care provider was the first to arrive and perform CPR. AED analysis was performed in three of the ten instances (30%), and one shock was delivered. In three additional cases of the first-arrivals, a home care provider had begun preparing defibrillation (AED), but analysis was not achieved before EMS arrived. In 16 of the 28 dispatches (57%), a home care provider arrived after EMS while simultaneous arrivals occurred in two cases (Fig 1). In the remaining 32 OHCA cases, no home care provider was dispatched. In nine cases, the reason was that other healthcare personnel was already present at the site. In two cases, the address was unknown. Various other reasons were cited for the remaining 21 cases.

Table 1 shows characteristics for all registered OHCA cases, with or without home care provider being dispatched, with various subgroups. No differences in age (P = 0.21), sex (P = 0.43) or patient status at hospital arrival between groups were detected (P = 0.71). When a home care provider arrived before ambulance services, the median ambulance response time was 9 min compared to 5 min and 6 min when a home care provider arrived after or simultaneously with ambulance services, respectively. The median ambulance response time was 4 min in cases where no home care providers were dispatched.

During the study period, 46 home care provider dispatch calls were executed from the EMD. Two calls were unintentional as the OHCA occurred outside the study municipality. Four calls failed, one caused by call system malfunction, one because no home care provider was within ten km of the OHCA site and two calls were rejected by the providers. In 91% (40/44) of cases, the call was accepted by at least one home care provider who subsequently arrived at the site. For 12 of the dispatches, no resuscitation attempts were performed as six patients did not have cardiac arrest and six were found with obvious signs of death.

Table 2 summarizes and compares the 40 dispatch calls. The age of patients without cardiac arrest were lower than patients with cardiac arrest (P<0.001). Both in dispatches to cardiac arrests and to other cases, the majority of patients were men. In 19 of the 28 dispatch cases (68%) two home care providers arrived.

The average delay before home care providers were activated was 2 min 20 s, as counted from the receipt of the emergency call by EMD (no difference between groups; P = 0.99).

This article describes the implementation of a novel AED first-responder programme concerning the dispatch of home care providers in parallel with conventional EMS in cases of suspected OHCA. The activation of the providers was EMD-controlled by the use of smartphones with bespoke equipment.

Previous studies have described programmes in which laypersons, police officers and fire-fighters have acted as first-responders in the event of a nearby OHCA to provide CPR and early defibrillation[14,16,21,22,27–30], but the presence of such groups can be low in sparsely populated rural districts. In contrast, mobile home care providers are working locally around the clock to support elderly and other citizens in need of care, and their deployment as first-responders to OHCAs could prove valuable. In this study, the providers were given systematic training in the use of AED and to perform CPR in a 2.5-hour course followed by 30 min of instruction in utilizing the smartphone dispatch system.

With the successful dispatch of home care providers in almost half of all suspected OHCA cases and their arrival before ambulance services in more than a third of the cases, the expected rate as assessed before the study was reached. In addition, our results are comparable to those of previous first-responder studies. In a study considering laypersons as first-responders the responders were dispatched to 58% of OHCA cases [22]. A study involving fire-fighters as first-responders reported that the first-responders were dispatched in 66% of all OHCA cases and arrived before EMS in 36% of all dispatches [14]. A study of police officers reported dispatch to 54% of cardiac arrests and arrival before EMS in 16% of cases [16]. Another study recruiting both laypersons and police officers as first-responders in rural areas reported dispatch to 40% of all OHCA events. Moreover, the mixed group arrived before EMS in 47% of the dispatches [21].

In three of the cases (30%) in which the home care providers in our study were the first to arrive, they performed AED analysis and in one case AED shock was delivered (10%). In three other cases, a home care provider had begun preparing an AED but did not complete AED connection before ambulance arrival.

A previous first-responder study has reported that an AED was connected in 43.5% of OHCA cases in a rural area [21]. Another study reported that the AED had been connected before EMS arrival for 23.1% of dispatches [22]. In our study, the first home care provider to arrive had instructions to focus on performing CPR and apply AED only after the arrival of a second provider; CPR was thus performed in all first arrivals. In two cases, a provider would have been activated if the SimaGo system had allowed providers to be dispatched to non-address locations, an option that should be considered for future first-responder systems.

A short response time of ambulances was the typical reason for non-dispatch of home care providers. It has been recommended that first-responders should be dispatched irrespective of EMS response times [22]. We cannot rule out that in spite of the low ambulance response time, the providers would have arrived before the ambulance if they had been alerted. However, when they did arrive before the ambulance, the median ambulance response time was 9 min as opposed to 5 min when an ambulance arrived first. Thus, the chance of provider first-arrival seems limited when an ambulance is nearby.

The cars used by the providers in our study had no siren. Because of the acknowledged risk of traffic accidents, it was stressed that all traffic regulations were to be followed strictly. No traffic accidents or safety issues were reported.

The delay of 2 min 20 s between the receipt of the emergency call by EMD and the dispatch of home care providers decreased the chance of first arrival. A previous study has reported delays of about 2 min, primarily caused by latency in identifying the emergency as a cardiac arrest [14]. First-responder programmes should give priority to minimizing such delays, for instance by alerting the providers when specific keywords are recognized by EMD personnel. However, such activation could increase the risk of providers being dispatched to non-cardiac arrest emergencies. In a study of first-responders who were dispatched not only to suspected OHCA cases but also to emergencies concerning unconscious patients, only 4.9% of all dispatches met with actual cardiac arrest cases as opposed to 70% in our study. However, despite their location in an urban area with short EMS response times, the first-responders in that study arrived before EMS in 73% of all cases [19].

Almost all OHCAs for which the home care providers in our study were dispatched occurred in a private home, as found in other studies as well [22]. We consider this a strength as most cardiac arrests occur in areas where AED availability is limited [3]. In the post-dispatch responses given by home care providers, 95% reported that they had felt largely or to some extent prepared to manage initial resuscitation. This is a very encouraging result that compares with or surpasses satisfaction results from other first-responder programmes that have studied fire-fighters, police officers and lay volunteers [31–33].

The studied home care providers were suited to act as first-responders. In residential and rural districts, home care providers could be considered for deployment as first-responders. Follow-up studies will allow further evaluation of home care provider arrivals and patient survival.