Response rate of the community first responder notification system for out-of-hospital cardiac arrest patients: an experience from Thailand

Article information

J EMS Med. 2025;4(3):55-62

Publication date (electronic) : 2025 September 29

doi : https://doi.org/10.35616/jemsm.2025.00171

Sattha Riyapan^,1,2, Soravit Manopetchkasem¹, Pannaporn Choosak¹, Bongkot Somboonkul², Jirayu Chantanakomes¹, Nattida Phinyo², Pannaphat Konwitthayasin², Kanpaphop Buangam², Panisara Seangsung²

¹Department of Emergency Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand

²Siriraj EMS Center, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand

Correspondence to: Sattha Riyapan Department of Emergency Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, 2 Wanglang Road, Bangkok-Noi, Bangkok 10700, Thailand E-mail: sattha.riy@mahidol.ac.th

Received 2025 June 8; Revised 2025 July 20; Accepted 2025 September 10.

Abstract

INTRODUCTION

Out-of-hospital cardiac arrest (OHCA) is a major public health concern and one of the most life-threatening emergencies. The survival-to-discharge rate for OHCA patients has been reported at only 2% to 11% [1], a figure that varies with geography and the efficiency of the response system. The American Heart Association has emphasized the importance of an effective response system, known as the chain of survival [2]. Recent evidence suggests that not all links in this chain contribute equally to outcomes [3]. The first two links—promptly calling for help and rapidly initiating chest compressions—have been shown to improve survival more than other factors.

However, most OHCA events occur at home or in public places [4], where medical providers are not typically present to perform cardiopulmonary resuscitation (CPR). In such situations, community members are required to provide bystander CPR. International literature has emphasized the importance of bystander CPR, leading to expanded efforts in public CPR education [5]. In addition to broad CPR training, several projects have recruited and trained community first responder (CFR) volunteers to initiate CPR before ambulance arrival [6-12]. More recently, activation systems have been implemented to alert nearby CFRs when suspected cardiac arrest cases are reported, aiming to increase bystander CPR and survival rates.

A Swedish randomized controlled trial demonstrated that activating CFRs during OHCA significantly increased bystander CPR compared with controls [13]. Similarly, in the Netherlands, CFR system implementation increased bystander CPR rates from 78% to 91% and improved survival to discharge from 26% to 39% [14]. Although these findings highlight the potential of CFR systems, challenges remain, particularly regarding CFR response rates. Studies in developed countries such as Australia, New Zealand [15], and Singapore [16] have shown that CFRs respond to about one-fourth of OHCA activations, with only 14% assisting in resuscitation. To our knowledge, little evidence is available on CFR response in developing countries.

In Thailand, CFR systems are not yet nationwide. Only a few emergency medical services (EMS) agencies have piloted CFR programs [17,18], and no published data exist on the Thai CFR notification system. The Siriraj Emergency Medical Service (SiEMS) Center launched a CFR program in 2022, using a social media application for activation. The system became operational for real OHCA cases in early 2023. The project involved training CFRs, setting up the activation mechanism, and auditing the response system. After implementation, this study aimed to assess the effectiveness of the CFR program, focusing on response rates and the proportion of CFRs arriving before ambulances. The study also sought to identify factors that promote CFR response as well as barriers to participation in real OHCA events.

METHODS

RESULTS

During the study period (August 2023 to December 2024), SiEMS resuscitated 381 OHCA patients. CFRs were activated in 67 patients (17.6% of total OHCA cases included in the CFR activation system), while 314 patients (82.4%) did not undergo CFR activation. Among these 314 patients, 110 cases (35.0%) occurred outside the CFR activation timeframe, whereas 204 cases (65.0%) had no documented reason for non-activation. The data flow of the study is illustrated in Fig. 1.

Fig. 1.

Data flow this study. OHCA, out-of-hospital cardiac arrest; CFR, community first responders.

Table 1 presents the characteristics of OHCA patients with activated CFRs. In this group, 55.2% were male, 27.8% had heart disease as an underlying condition, 61.5% received bystander CPR, and 7.5% had public AED use. Additionally, 27.3% achieved prehospital ROSC, 12.5% survived to hospital admission following cardiac arrest, and only 1.6% survived to hospital discharge.

Table 1.

Baseline characteristics of out-of-hospital cardiac arrest patients with community first responder system activation

The CFR activation system alerted responders in 67 OHCA cases, with a median of 3 CFRs notified per case (Table 2). Among these, 12 patients had CFRs who accepted the notification (20.3%). Of those, 11 CFRs arrived at the scene and either provided first aid or assisted the EMS team (18.6%). Only three CFRs reached the scene before EMS arrival and participated in resuscitation (5.1%).

Table 2.

CFR activation and involvement in resuscitation

Of the 90 trained CFRs, 46 were activated and later responded to the survey. Among these, only seven CFRs accepted the notification and responded at the scene. Among survey respondents, 60.1% were male. Education levels were as follows: 21.7% had completed intermediate school, 28.3% secondary school, and 50% held a bachelor’s degree or higher. Employment status showed that 2.2% were unemployed or retired, 84.8% were non-medical office workers, and 13.0% were medical personnel. Regarding CPR experience, 34.8% had performed CPR more than five times, 28.2% had performed CPR 2–5 times, 10.9% had performed CPR once, and 26.1% had never performed CPR on real patients. Table 3 summarizes the characteristics of CFRs who were activated and responded to the survey.

Table 3.

Baseline characteristics of community first responders who completed the survey

Across the 67 OHCA patients with CFR activation, the system generated 300 notifications. A total of 187 survey responses were received (62.3% response rate). Among respondents, 35.3% reported not seeing the notification. The most common reason was inability to access their phones at the time (40.9%). Of the 64.7% who did see the notifications, 90.1% either did not respond or declined due to being too far from the scene (55.0%) or being unavailable because of work obligations (43.1%). Fig. 2 illustrates survey responses, while Fig. 3 presents reasons for not seeing the notifications.

Fig. 2.

Bar chart illustrates the reported barriers that prevented community first responders from responding to activation notifications.

Fig. 3.

Pie chart illustrates the factors that prevented community first responders from noticing or viewing activation notifications.

DISCUSSION

This study identified the response rate of the CFR notification system for OHCA patients within the SiEMS coverage area. Of all notified cases, 20.3% were accepted, and 18.6% of CFRs arrived at the scene. Only 5.1% of CFRs arrived before ambulance personnel and supported the ALS team in resuscitating OHCA patients. To our knowledge, this is the first study in Thailand to report barriers preventing CFRs from responding to the scene.

The response rate of our CFR notification system differed from those in other countries, likely due to several factors, including the notification system used, the number of CFRs, geographic conditions, and economic constraints. In our study, only 20.3% of OHCA cases had CFRs who accepted the notification. By comparison, in Singapore, 11% of OHCA cases had CFR acceptance in 2015, which rose to 43% in 2019. This improvement was attributed to Singapore’s adoption of the “myResponder” mobile application in 2015, which incorporated real-time GPS tracking to activate CFRs [16]. In contrast, our system relied on LINE Official to send notifications, using GPS only during initial registration to determine CFR location [23]. Consequently, the actual location of CFRs at the time of an OHCA often differed from their registered location, which survey results confirmed as a major barrier: 55% of CFRs saw the notification but did not respond because they were too far from the scene. Real-time GPS activation is clearly more accurate, though it requires higher maintenance costs. Singapore allocated significant resources to develop and sustain its mobile app. In Thailand, the cost-effectiveness of such a system was not considered sufficient to justify its use, which led to reliance on LINE Official. Additionally, Singapore recruited a far larger pool of CFRs (9 CFRs per 10,000 population in our study vs. 80 CFRs per 10,000 in Singapore by 2019). This was possible because Singapore did not require CPR training prior to registration, which increased app installations and registered responders. By 2019, Singapore had 47,000 registered CFRs, a major factor contributing to higher notification acceptance rates.

Sweden offers another example. Its CFR notification system, “SMS-lifesaver,” was introduced in 2008. A randomized controlled trial conducted between 2012 and 2013 in Stockholm County (6,519 km², population 2.3 million) activated CFRs via telephone and SMS [13]. Recruitment campaigns and CPR training courses initially registered 5,989 CFRs (26 per 10,000 population), increasing to 9,828 (43 per 10,000) by the trial’s end. This expansion resulted in a 61.6% CFR response rate [13], far higher than the 20.3% observed in our study. In comparison, our CFR program included only 90 volunteers, covering 12 km² with a population of 99,729 (9 CFRs per 10,000). These findings underscore that the number of CFRs is a key determinant of system response. Given that this is the first CFR study in Thailand with a relatively small sample of responders, we recommend that future programs aim to recruit at least 20 CFRs per 10,000 population within the coverage area to achieve a more acceptable response rate.

This study also found that only three CFRs arrived before the ambulance, which may be explained by limitations in system design. Specifically, our CFR notification process was not integrated with the dispatch center. Instead, CFRs were notified from the ambulance station, and the coordinator manually activated them based on distance and protocol. This manual step may have delayed notification. By contrast, the Singaporean and Swedish systems automatically activated CFRs according to real-time proximity [13,16]. This automation allowed more responders to arrive before the ambulance. For future development, we recommend upgrading the CFR system to be automatic and fully integrated with the dispatch center to minimize delays and improve early response rates.

Our study asked CFRs who did not receive notifications about the factors preventing them from doing so. The most common reason was the inability to access a telephone at the time, due to circumstances such as working hours or being in a car. The second reason was that CFRs did not hear or see the notification. These findings were consistent with studies from the United States and New Zealand, where common reasons for not seeing alerts included phones being muted, not hearing the signal, or being away from the device [7,15]. This issue arose in our system because notifications were sent through LINE Official, which required internet access and enabled phone notifications. If either was disabled, CFRs did not receive alerts. From the CFRs’ perspective, keeping mobile internet and notifications active at all times could intrude on privacy, increase data usage, and drain battery life, creating inconvenience for volunteers.

The investigators also surveyed barriers that prevented CFRs from responding and arriving at the scene. The results were consistent with findings from the United States, New Zealand, and Sweden. The most frequently cited reasons for not responding to alerts were work obligations, family or childcare responsibilities, and being located too far from the incident [7,15,24]. The primary barriers were therefore distance to the scene and the availability of CFRs. As noted earlier, our notification system initially included all CFRs within a 500-m radius of the scene. However, during the study period, many CFRs reported being too far away when the notification was received. This occurred because CFRs were often not present at their registered locations, as our system did not employ real-time GPS tracking but instead relied on self-reported locations. Although real-time GPS tracking could provide greater accuracy, it involves higher maintenance costs and raises potential privacy concerns. These considerations were the main reason our study used the LINE Official account to send notifications.

This study represents the first report on CFR response rates and barriers in Thailand. Overall, the data obtained can guide future projects in several ways. Our findings suggest that the program is feasible, with an acceptable initial response rate compared with prior studies. Adjustments to the workflow, such as expanding activation times, modifying distance thresholds, or refining the notification system, could further improve both response rates and response times. We also recommend increasing CFR recruitment. Additional validation studies and further investigations are warranted to support future implementation.

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