Incidence and Survival of Out-of-Hospital Cardiac Arrest in Public Housing Areas in 3 European Capitals.

BACKGROUND: Strategies to reach out-of-hospital cardiac arrests (called cardiac arrest) in residential areas and reduce disparities in care and outcomes are warranted. This study investigated incidences of cardiac arrests in public housing areas. METHODS: This register-based cohort study included cardiac arrest patients from Amsterdam (the Netherlands) from 2016 to 2021, Copenhagen (Denmark) from 2016 to 2021, and Vienna (Austria) from 2018 to 2021. Using Poisson regression adjusted for spatial correlation and city, we compared cardiac arrest incidence rates (number per square kilometer per year and number per 100 000 inhabitants per year) in public housing and other residential areas and examined the proportion of cardiac arrests within public housing and adjacent areas (100-m radius). RESULTS: Overall, 9152 patients were included of which 3038 (33.2%) cardiac arrests occurred in public housing areas and 2685 (29.3%) in adjacent areas. In Amsterdam, 635/1801 (35.3%) cardiac arrests occurred in public housing areas; in Copenhagen, 1036/3077 (33.7%); and in Vienna, 1367/4274 (32.0%). Public housing areas covered 42.4 (12.6%) of 336.7 km2 and 1 024 470 (24.6%) of 4 164 700 inhabitants. Across the capitals, we observed a lower probability of 30-day survival in public housing versus other residential areas (244/2803 [8.7%] versus 783/5532 [14.2%]). The incidence rates and rate ratio of cardiac arrest in public housing versus other residential areas were incidence rate, 16.5 versus 4.1 n/km2 per year; rate ratio, 3.46 (95% CI, 3.31-3.62) and incidence rate, 56.1 versus 36.8 n/100 000 inhabitants per year; rate ratio, 1.48 (95% CI, 1.42-1.55). The incidence rates and rate ratios in public housing versus other residential areas were consistent across the 3 capitals. CONCLUSIONS: Across 3 European capitals, one-third of cardiac arrests occurred in public housing areas, with an additional third in adjacent areas. Public housing areas exhibited consistently higher cardiac arrest incidences per square kilometer and 100 000 inhabitants and lower survival than other residential areas. Public housing areas could be a key target to improve cardiac arrest survival in countries with a public housing sector.

Cardiac arrest and cardiopulmonary resuscitation in the next decade: Predicting and shaping the impact of technological innovations.

INTRODUCTION: Cardiac arrest (CA) is the third leading cause of death, with persistently low survival rates despite medical advancements. This article evaluates the potential of emerging technologies to enhance CA management over the next decade, using predictions from the AI tools ChatGPT-4 and Gemini Advanced. METHODS: We conducted an exploratory literature review to envision the future of cardiopulmonary arrest (CA) management. Utilizing ChatGPT-4 and Gemini Advanced, we predicted implementation timelines for innovations in early recognition, CPR, defibrillation, and post-resuscitation care. We also consulted the AI to assess the consistency and reproducibility of the predictions. RESULTS: We extrapolate that healthcare may embrace new technologies, such as comprehensive monitoring of vital signs to activate the emergency system (wireless detectors, smart speakers, and wearable devices), use new innovative early CPR and early AED devices (robot CPR, wearable AEDs, and immersive reality), and post-resuscitation care monitoring (brain-computer interface). These technologies could enhance timely life-saving interventions for cardiac arrest. However, there are many ethical and practical challenges, particularly in maintaining patient privacy and equity. The two AI tools made different predictions, with a horizon for implementation ranging between three and eight years. CONCLUSION: Integrating advanced monitoring technologies and AI-driven tools offers hope in improving CA management. A balanced approach involving rigorous scientific validation and ethical oversight is necessary. Collaboration among technologists, medical professionals, ethicists, and policymakers is crucial to use these innovations ethically to reduce CA incidence and enhance outcomes. Further research is needed to enhance the reliability of AI predictive capabilities.

Sex Differences in Receipt of Bystander Cardiopulmonary Resuscitation Considering Neighborhood Racial and Ethnic Composition.

BACKGROUND: Bystander cardiopulmonary resuscitation (B-CPR) and defibrillation for out-of-hospital cardiac arrest (OHCA) vary by sex, with women being less likely to receive these interventions in public. It is unknown whether sex differences persist when considering neighborhood racial and ethnic composition. We examined the odds of receiving B-CPR stratified by location and neighborhood. We hypothesized that women in predominantly Black neighborhoods will have a lower odds of receiving B-CPR. METHODS AND RESULTS: We conducted a retrospective study using the Cardiac Arrest Registry to Enhance Survival (CARES). Neighborhoods were classified by census tract. We modeled the odds of receipt of B-CPR (primary outcome), automatic external defibrillation application, and survival to hospital discharge (secondary outcomes) by sex. CARES collected 457 621 arrests (2013-2019); after appropriate exclusion, 309 662 were included. Women who had public OHCA had a 14% lower odds of receiving B-CPR (odds ratio [OR], 0.86 [95% CI, 0.82-0.89]), but effect modification was not seen by neighborhood (P=not significant). In predominantly Black neighborhoods, women who had public OHCA had a 13% lower odds of receiving B-CPR (adjusted OR, 0.87 [95% CI, 0.76-0.98]) and 12% lower odds of receiving automatic external defibrillation application (adjusted OR, 0.88 [95% CI, 0.78-0.99]). In predominantly Hispanic neighborhoods, women who had public OHCA were less likely to receive B-CPR (adjusted OR, 0.83 [95% CI, 0.73-0.96]) and less likely to receive automatic external defibrillation application (adjusted OR, 0.74 [95% CI, 0.64-0.87]). CONCLUSIONS: Women with public OHCA have a decreased likelihood of receiving B-CPR and automatic external defibrillation application. Findings did not differ significantly according to neighborhood composition. Despite this, our work has implications for considering strategies to reduce disparities around bystander response.

Public Out-of-Hospital Cardiac Arrest in Residential Neighborhoods.

BACKGROUND: Although one-half of all public out-of-hospital cardiac arrests (OHCAs) occur outside private homes in residential neighborhoods, their characteristics and outcomes remain unexplored. OBJECTIVES: The authors assessed interventions before ambulance arrival and survival for public OHCA patients in residential neighborhoods. METHODS: Public OHCAs from Vienna (2018-2021) and Copenhagen (2016-2020) were designated residential neighborhoods or nonresidential areas. Interventions (cardiopulmonary resuscitation [CPR], automated external defibrillator [AED] attached, and defibrillation) and 30-day survival were compared using a generalized estimation equation model adjusted for age and time of day and presented as ORs. RESULTS: We included 1,052 and 654 public OHCAs from Vienna and Copenhagen, respectively, and 68% and 55% occurred in residential neighborhoods, respectively. The likelihood of CPR, defibrillation, and survival in residential neighborhoods vs nonresidential areas (reference) were as follows: CPR Vienna, 73% vs 78%, OR: 0.78 (95% CI: 0.57-1.06), CPR Copenhagen, 83% vs 90%, OR: 0.54 (95% CI: 0.34-0.88), and CPR combined, 76% vs 84%, OR: 0.70 (95% CI: 0.53-0.90); AED attached Vienna, 36% vs 44%, OR: 0.69 (95% CI: 0.53-0.90), AED attached Copenhagen, 21% vs 43%, OR: 0.33 (95% CI: 0.24-0.48), and AED attached combined, 31% vs 44%, OR: 0.53 (95% CI: 0.42-0.65); defibrillation Vienna, 14% vs 20%, OR: 0.61 (95% CI: 0.43-0.87), defibrillation Copenhagen, 16% vs 36%, OR: 0.35 (95% CI: 0.24-0.51), and defibrillation combined, 15% vs 27%, OR: 0.46 (95% CI: 0.36-0.61); and 30-day survival rate Vienna, 21% vs 26%, OR: 0.84 (95% CI: 0.58-1.20), 30-day survival rate Copenhagen, 33% vs 44%, OR: 0.65 (95% CI: 0.47-0.90), and 30-day survival rate combined, 25% vs 36%, OR: 0.73 (95% CI: 0.58-0.93). CONCLUSIONS: Two-thirds of public OHCAs occurred in residential neighborhoods with fewer resuscitative efforts before ambulance arrival and lower survival than in nonresidential areas. Targeted efforts to improve early CPR and defibrillation for public OHCA patients in residential neighborhoods are needed.

Community intervention to improve defibrillation before ambulance arrival in residential neighbourhoods with a high risk of out-of-hospital cardiac arrest: study protocol of a cluster-randomised trial (the CARAMBA trial).

INTRODUCTION: In Denmark, multiple national initiatives have been associated with improved bystander defibrillation and survival following out-of-hospital cardiac arrest (OHCA) in public places. However, OHCAs in residential neighbourhoods continue to have poor outcomes. The Cardiac Arrest in Residential Areas with MoBile volunteer responder Activation trial aims to improve bystander defibrillation and survival following OHCA in residential neighbourhoods with a high risk of OHCA. The intervention consists of: (1) strategically deployed automated external defibrillators accessible at all hours, (2) cardiopulmonary resuscitation (CPR) training of residents and (3) recruitment of residents for a volunteer responder programme. METHODS AND ANALYSIS: This is a prospective, pair-matched, cluster-randomised, superiority trial with clusters of 26 residential neighbourhoods, testing the effectiveness of the intervention in a real-world setting. The areas are randomised for intervention or control. Intervention and control areas will receive the standard OHCA emergency response, including volunteer responder activation. However, targeted automated external defibrillator deployment, CPR training and volunteer responder recruitment will only be provided in the intervention areas. The primary outcome is bystander defibrillation, and the secondary outcome is 30-day survival. Data on patients who had an OHCA will be collected through the Danish Cardiac Arrest Registry. ETHICS AND DISSEMINATION: Approval to store OHCA data has been granted from the Legal Office, Capital Region of Denmark (j.nr: 2012-58-0004, VD-2018-28, I-Suite no: 6222, and P-2021-670). In Denmark, formal approval from the ethics committee is only obtainable when the study regards testing medicine or medical equipment on humans or using genome or diagnostic imagine as data source. The Ethics Committee of the Capital Region of Denmark has evaluated the trial and waived formal approval unnecessary (H-19037170). Results will be published in peer-reviewed papers and shared with funders, stakeholders, and housing organisations through summaries and presentations. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT04446585).

Long-Term Quality of Life After Out-of-Hospital Cardiac Arrest.

Importance: Allocating resources to increase survival after cardiac arrest requires survivors to have a good quality of life, but long-term data are lacking. Objective: To determine the quality of life of survivors of out-of-hospital cardiac arrest from 2001 to 2019. Design, Setting, and Participants: This survey study used the EuroQol Health Questionnaire, 12-Item Short Form Health Survey (SF-12), and Hospital Anxiety and Depression Scale (HADS) to assess the health-related quality of life of all adult survivors of out-of-hospital cardiac arrest included in the Danish Cardiac Arrest Registry between June 1, 2001, and August 31, 2019, who were alive in October 2020 (follow-up periods, 0-1, >1-2, >2-4, >4-6, >6-8, >8-10, >10-15, and >15-20 years since arrest). The survey was conducted from October 1, 2020, through May 31, 2021. Exposure: All patients who experienced an out-of-hospital cardiac arrest. Main Outcome and Measures: Self-reported health was measured using the EuroQol Health Questionnaire index (EQ index) score and EQ visual analog scale. Physical and mental health were measured using the SF-12, and anxiety and depression were measured using the HADS. Descriptive statistics were used for the analysis. Results: Of 4545 survivors, 2552 (56.1%) completed the survey, with a median follow-up since their event of 5.5 years (IQR, 2.9-8.9 years). Age was comparable between responders and nonresponders (median [IQR], 67 [58-74] years vs 68 [56-78] years), and 2075 responders (81.3%) were men and 477 (18.7%) women (vs 1473 male [73.9%] and 520 female [26.1%] nonresponders). For the shortest follow-up (0-1 year) and longest follow-up (>15-20 years) groups, the median EQ index score was 0.9 (IQR, 0.7-1.0) and 0.9 (0.8-1.0), respectively. For all responders, the mean (SD) SF-12 physical health score was 43.3 (12.3) and SF-12 mental health score, 52.9 (8.3). All 3 scores were comparable to a general Danish reference population. Based on HADS scores, a low risk for anxiety was reported by 73.0% (54 of 74) of 0- to 1-year survivors vs 89.3% (100 of 112) of greater than 15- to 20-year survivors; for symptoms of depression, these proportions were 79.7% (n = 59) and 87.5% (n = 98), respectively. Health-related quality of life was similar in survivor groups across all follow-up periods. Conclusions and Relevance: Among this survey study's responders, who comprised more than 50% of survivors of out-of-hospital cardiac arrest in Denmark, long-term health-related quality of life up to 20 years after their event was consistently high and comparable to that of the general population. These findings support resource allocation and efforts targeted to increasing survival after out-of-hospital cardiac arrest.

Follow-up on volunteer responders dispatched for out-of-hospital cardiac arrests: Addressing the psychological and physical impact.

Introduction: Smartphone technology is increasingly used to engage lay people as volunteer responders in resuscitation attempts. Attention has recently been drawn to how resuscitation attempts may impact bystanders. Attempting resuscitation in out-of-hospital cardiac arrests (OHCA) may be an overwhelming experience and, in some cases, difficult to cope with. We developed a volunteer responder follow-up program to systematically measure the psychological and physical impact on volunteer responders dispatched for OHCAs. Methods and Results: The nationwide Danish volunteer responder program dispatches volunteer responders for presumed cardiac arrests. 90 min after notification of a potential nearby cardiac arrest, all volunteer responders receive a survey, and are asked to self-report their mental state of mind after the event. The volunteer responders are also asked to disclose any physical injury they sustained in relation to the event. Volunteer responders who report severe mental effects are offered a defusing conversation by a trained nurse. Between 1 September 2017 and 31 December 2022, the Danish volunteer responder program has alerted 177,866 volunteer responders for 10,819 presumed cardiac arrest alerts. Of 177,866 alerted volunteers responders, 62,711 accepted the alarm. In the same period, 7,317 cancelled their registration. From January 2019 to 31 December 31 2022, a total of 535 volunteer responders were offered a defusing consultation. Conclusion: The Danish volunteer responder follow-up program is carried out to assess the psychological and physical risks of responding to a suspected OHCA. We suggest a survey-based method for systematic screening of volunteer responders that allow volunteer responders to report any physical injury or need of psychological follow-up. The person providing defusing should be a trained and experienced healthcare professional.

KIDS SAVE LIVES: Basic Life Support Education for Schoolchildren: A Narrative Review and Scientific Statement From the International Liaison Committee on Resuscitation.

BACKGROUND: Basic life support education for schoolchildren has become a key initiative to increase bystander cardiopulmonary resuscitation rates. Our objective was to review the existing literature on teaching schoolchildren basic life support to identify the best practices to provide basic life support training in schoolchildren. METHODS: After topics and subgroups were defined, a comprehensive literature search was conducted. Systematic reviews and controlled and uncontrolled prospective and retrospective studies containing data on students <20 years of age were included. RESULTS: Schoolchildren are highly motivated to learn basic life support. The CHECK-CALL-COMPRESS algorithm is recommended for all schoolchildren. Regular training in basic life support regardless of age consolidates long-term skills. Young children from 4 years of age are able to assess the first links in the chain of survival. By 10 to 12 years of age, effective chest compression depths and ventilation volumes can be achieved on training manikins. A combination of theoretical and practical training is recommended. Schoolteachers serve as effective basic life support instructors. Schoolchildren also serve as multipliers by passing on basic life support skills to others. The use of age-appropriate social media tools for teaching is a promising approach for schoolchildren of all ages. CONCLUSIONS: Schoolchildren basic life support training has the potential to educate whole generations to respond to cardiac arrest and to increase survival after out-of-hospital cardiac arrest. Comprehensive legislation, curricula, and scientific assessment are crucial to further develop the education of schoolchildren in basic life support.

KIDS SAVE LIVES: Basic Life Support Education for Schoolchildren: A Narrative Review and Scientific Statement From the International Liaison Committee on Resuscitation.

BACKGROUND: Basic life support education for schoolchildren has become a key initiative to increase bystander cardiopulmonary resuscitation rates. Our objective was to review the existing literature on teaching schoolchildren basic life support to identify the best practices to provide basic life support training in schoolchildren. METHODS: After topics and subgroups were defined, a comprehensive literature search was conducted. Systematic reviews and controlled and uncontrolled prospective and retrospective studies containing data on students <20 years of age were included. RESULTS: Schoolchildren are highly motivated to learn basic life support. The CHECK-CALL-COMPRESS algorithm is recommended for all schoolchildren. Regular training in basic life support regardless of age consolidates long-term skills. Young children from 4 years of age are able to assess the first links in the chain of survival. By 10 to 12 years of age, effective chest compression depths and ventilation volumes can be achieved on training manikins. A combination of theoretical and practical training is recommended. Schoolteachers serve as effective basic life support instructors. Schoolchildren also serve as multipliers by passing on basic life support skills to others. The use of age-appropriate social media tools for teaching is a promising approach for schoolchildren of all ages. CONCLUSIONS: Schoolchildren basic life support training has the potential to educate whole generations to respond to cardiac arrest and to increase survival after out-of-hospital cardiac arrest. Comprehensive legislation, curricula, and scientific assessment are crucial to further develop the education of schoolchildren in basic life support.

Volunteer responder provision of support to relatives of out-of-hospital cardiac arrest patients: a qualitative study.

OBJECTIVES: Smartphone dispatch of volunteer responders for out-of-hospital cardiac arrest (OHCA) is implemented worldwide. While basic life support courses prepare participants to provide CPR, the courses rarely address the possibility of meeting a family member or relative in crisis. This study aimed to examine volunteer responders' provision of support to relatives of cardiac arrest patients and how relatives experienced the interaction with volunteer responders. DESIGN: In this qualitative study, we conducted 16 semistructured interviews with volunteer responders and relatives of cardiac arrest patients. SETTING: Interviews were conducted face to face and by video and recorded and transcribed verbatim. PARTICIPANTS: Volunteer responders dispatched to cardiac arrests and relatives of cardiac arrest patients were included in the study. Participants were included from all five regions of Denmark. RESULTS: A thematic analysis was performed with inspiration from Braun and Clarke. We identified three themes: (1) relatives' experiences of immediate relief at arrival of assistance, (2) volunteer responders' assessment of relatives' needs and (3) the advantage of being healthcare educated. CONCLUSIONS: Relatives to out-of-hospital cardiac arrest patients benefited from volunteer responders' presence and support and experienced the mere presence of volunteer responders as supportive. Healthcare-educated volunteer responders felt confident and skilled to provide care for relatives, while some non-healthcare-educated volunteer responders felt they lacked the proper training and knowledge to provide emotional support for relatives. Future basic life support courses should include a lesson on how to provide emotional support to relatives of cardiac arrest patients.

Smartphone-activated volunteer responders and bystander defibrillation for out-of-hospital cardiac arrest in private homes and public locations.

AIMS: To investigate the association between the arrival of smartphone-activated volunteer responders before the Emergency Medical Services (EMS) and bystander defibrillation in out-of-hospital cardiac arrest (OHCA) at home and public locations. METHODS AND RESULTS: This is a retrospective study (1 September 2017-14 May 2019) from the Stockholm Region of Sweden and the Capital Region of Denmark. We included 1271 OHCAs, of which 1029 (81.0%) occurred in private homes and 242 (19.0%) in public locations. The main outcome was bystander defibrillation. At least one volunteer responder arrived before EMS in 381 (37.0%) of OHCAs at home and 84 (34.7%) in public. More patients received bystander defibrillation when a volunteer responder arrived before EMS at home (15.5 vs. 2.2%, P < 0.001) and in public locations (32.1 vs. 19.6%, P = 0.030). Similar results were found among the 361 patients with an initial shockable heart rhythm (52.7 vs. 11.5%, P < 0.001 at home and 60.0 vs. 37.8%, P = 0.025 in public). The standardized probability of receiving bystander defibrillation increased with longer EMS response times in private homes. The 30-day survival was not significantly higher when volunteer responders arrived before EMS (9.2 vs. 7.7% in private homes, P = 0.41; and 40.5 vs. 35.4% in public locations, P = 0.44). CONCLUSION: Bystander defibrillation was significantly more common in private homes and public locations when a volunteer responder arrived before the EMS. The standardized probability of bystander defibrillation increased with longer EMS response times in private homes. Our findings support the activation of volunteer responders and suggest that volunteer responders could increase bystander defibrillation, particularly in private homes.

Contemporary levels of cardiopulmonary resuscitation training in Denmark.

Aim: Many efforts have been made to train the Danish population in cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) use. We assessed CPR and AED training levels among the broad Danish population and volunteer responders. Methods: In November 2018, an electronic cross-sectional survey was sent to (1) a representative sample of the general Danish population (by YouGov) and (2) all volunteer responders in the Capital Region of Denmark. Results: A total of 2,085 people from the general population and 7,768 volunteer responders (response rate 36%) completed the survey. Comparing the general Danish population with volunteer responders, 81.0% (95% CI 79.2-82.7%) vs. 99.2% (95% CI 99.0-99.4%) p < 0.001 reported CPR training, and 54.0% (95% CI 51.8; 56.2) vs. 89.5% (95% CI 88.9-90.2) p < 0.001 reported AED training, at some point in life.In the general population, the unemployed and the self-employed had the lowest proportion of training with CPR training at 71.9% (95% CI 68.3-75.4%) and 65.4% (95% CI 53.8-75.8%) and AED training at 39.0% (95% CI 35.2-42.9%) and 34.6% (95% CI 24.2-46.2%), respectively.Applicable to both populations, the workplace was the most frequent training provider. Among 18-29-year-olds in the general population, most reported training when acquiring a driver's license. Conclusions: A large majority of the Danish population and volunteer responders reported previous CPR/AED training. Mandatory training when acquiring a driver's license and training through the workplace seems to disseminate CPR/AED training effectively. However, new strategies reaching the unemployed and self-employed are warranted to ensure equal access.

Activation of Citizen Responders to Out-of-Hospital Cardiac Arrest During the COVID-19 Outbreak in Denmark 2020.

Background Little is known about how COVID-19 influenced engagement of citizen responders dispatched to out-of-hospital cardiac arrest (OHCA) by a smartphone application. The objective was to describe and analyze the Danish Citizen Responder Program and bystander interventions (both citizen responders and nondispatched bystanders) during the first COVID-19 lockdown in 2020. Methods and Results All OHCAs from January 1, 2020, to June 30, 2020, with citizen responder activation in 2 regions of Denmark were included. We compared citizen responder engagement for OHCA in the nonlockdown period (January 1, 2020, to March 10, 2020, and April 21, 2020, to June 30, 2020) with the lockdown period (March 11, 2020, to April 20, 2020). Data are displayed in the order lockdown versus nonlockdown period. Bystander cardiopulmonary resuscitation rates did not differ in the 2 periods (99% versus 92%; P=0.07). Bystander defibrillation (9% versus 14%; P=0.4) or return-of-spontaneous circulation (23% versus 23%; P=1.0) also did not differ. A similar amount of citizen responders accepted alarms during the lockdown (6 per alarm; interquartile range, 6) compared with the nonlockdown period (5 per alarm; interquartile range, 5) (P=0.05). More citizen responders reported performing chest-compression-only cardiopulmonary resuscitation during lockdown compared with nonlockdown (79% versus 59%; P=0.0029), whereas fewer performed standardized cardiopulmonary resuscitation, including ventilations (19% versus 38%; P=0.0061). Finally, during lockdown, more citizen responders reported being not psychologically affected by attending an OHCA compared with nonlockdown period (68% versus 56%; P<0.0001). Likewise, fewer reported being mildly affected during lockdown (26%) compared with nonlockdown (35%) (P=0.003). Conclusions The COVID-19 lockdown in Denmark was not associated with decreased bystander-initiated resuscitation in OHCAs attended by citizen responders.

Citizen Responder Activation in Out-of-Hospital Cardiac Arrest by Time of Day and Day of Week.

Background We aim to examine diurnal and weekday variations in citizen responder availability and intervention at out-of-hospital cardiac arrest (OHCA) resuscitation. Methods and Results We included confirmed OHCAs where citizen responders were activated by a smartphone application in the Capital Region of Denmark between September 1, 2017 and August 31, 2018. OHCAs were analyzed by time of day (daytime: 07:00 am-03:59 pm, evening: 4:00-11:59 pm, and nighttime: 12:00-06:59 am) and day of week (Monday-Friday or Saturday-Sunday/public holidays). We included 438 OHCAs where 6836 citizen responders were activated. More citizen responders accepted alarms in the evening (mean 4.8 [95% CI, 4.4-5.3]) compared with daytime (3.7 [95% CI, 3.4-4.4]) and nighttime (1.8 [95% CI, 1.5-2.2]) (P<0.001), and more accepted alarms during weekends (4.3 [95% CI, 3.8-4.9]) compared with weekdays (3.4 [95% CI, 3.2-3.7]) (P<0.001). Proportion of OHCAs where at least 1 citizen responder arrived before Emergency Medical Services were significantly different between day (42.9%), evening (50.3%), and night (26.1%) (P<0.001), and between weekdays (37.2%) and weekends (53.5%) (P=0.002). When responders arrived before Emergency Medical Services, there was no difference of bystander cardiopulmonary resuscitation or defibrillation between daytime, evening, and nighttime (P=0.75 and P=0.22, respectively) or between weekend and weekdays (P=0.29 and P=0.12, respectively). Conclusions Citizen responders were more likely to accept OHCA alarms during evening and weekends, with the highest proportion of responders arriving before Emergency Medical Services in the evening. However, there was no significant difference in delivering cardiopulmonary resuscitation or early defibrillation among cases where citizen responders arrived before Emergency Medical Services. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03835403.

Association of Psychological Distress, Contextual Factors, and Individual Differences Among Citizen Responders.

Background Little is known about the psychological risks of dispatched citizen responders who have participated in resuscitation attempts. Methods and Results A cross-sectional survey study was performed with 102 citizen responders who participated in a resuscitation attempt from July 23, 2018, to August 22, 2018, in the Capital Region of Denmark. Psychological distress, defined as symptoms of posttraumatic stress disorder, was assessed 3 weeks after the resuscitation attempt and measured with the Impact of Event Scale-Revised. Perceived stress was measured with the Perceived Stress Scale. Individual differences were assessed as the personality traits of agreeableness, conscientiousness, extraversion, neuroticism, and openness to experience with the Big Five Inventory, general self-efficacy, and coping mechanisms (Brief Coping Orientation to Problems Experienced Inventory). Associations between continuous variables were examined with the Pearson correlation. The associations between psychological distress levels and contextual factors and individual differences were analyzed in multivariable linear regression models to determine factors independently associated with psychological distress levels. The mean overall posttraumatic stress disorder score was 0.65 of 12; the mean perceived stress score was 7.61 of 40. The most common coping mechanisms were acceptance and emotional support. Low perceived stress was significantly associated with high general self-efficacy, and high perceived stress was significantly associated with high scores on neuroticism and openness to experience. Non-healthcare professionals were less likely to report symptoms of posttraumatic stress disorder. Conclusions Citizen responders who participated in resuscitation reported low levels of psychological distress. Individual differences were significantly associated with levels of psychological distress and should be considered when engaging citizen responders in resuscitation.

Implications for cardiac arrest coverage using straight-line versus route distance to nearest automated external defibrillator.

AIM: Quantifying the ratio describing the difference between "true route" and "straight-line" distances from out-of-hospital cardiac arrests (OHCAs) to the closest accessible automated external defibrillator (AED) can help correct likely overestimations in AED coverage. Furthermore, we aimed to examine to what extent the closest AED based on true route distance differed from the closest AED using "straight-line". METHODS: OHCAs (1994-2016) and AEDs (2016) in Copenhagen, Denmark and in Toronto, Canada (2007-2015 and 2015, respectively) were identified. Three distances were calculated between OHCA and target AED: 1) the straight-line distance ("straight-line") to the closest AED, 2) the corresponding true route distance to the same AED ("true route"), and 3) the closest AED based only on true route distance ("shortest true route"). The ratio between "true route" and "straight-line" distance was calculated and differences in AED coverage (an OHCA ≤ 100 m of an accessible AED) were examined. RESULTS: The "straight-line" AED coverage of 100 m was 24.2% (n = 2008/8295) in Copenhagen and 6.9% (n = 964/13916) in Toronto. The corresponding "true route" distance reduced coverage to 9.5% (n = 786) and 3.8% (n = 529), respectively. The median ratio between "true route" and "straight-line" distance was 1.6 in Copenhagen and 1.4 in Toronto. In 26.1% (n = 2167) and 22.9% (n = 3181) of all Copenhagen and Toronto OHCAs respectively, the closest AED in "shortest true route" was different than the closest AED initially found by "straight-line". CONCLUSIONS: Straight-line distance is not an accurate measure of distance and overestimates the actual AED coverage compared to a more realistic true route distance by a factor 1.4-1.6.

Risk of Physical Injury for Dispatched Citizen Responders to Out-of-Hospital Cardiac Arrest.

Background Citizen responder programs are implemented worldwide to dispatch volunteer citizens to participate in out-of-hospital cardiac arrest resuscitation. However, the risk of injuries in relation to activation is largely unknown. We aimed to assess the risk of physical injury for dispatched citizen responders. Methods and Results Since September 2017, citizen responders have been activated through a smartphone application when located close to a suspected cardiac arrest in the Capital Region of Denmark. A survey was sent to all activated citizen responders, including a specific question about risk of acquiring an injury during activation. We included all surveys from September 1, 2017, to May 15, 2020. From May 15, 2019, to May 15, 2020, we followed up on all survey nonresponders by phone call, e-mail, or text messages to examine if nonresponders were at higher risk of severe or fatal injuries. In 1665 suspected out-of-hospital cardiac arrests, 9574 citizen responders were dispatched and 76.6% (7334) answered the question regarding physical injury. No injury was reported by 99.3% (7281) of the responders. Being at risk of physical injury was reported by 0.3% (24), whereas 0.4% (26) reported an injury (25 minor injuries and 1 severe injury [ankle fracture]). When following up on nonresponders (2472), we reached 99.1% (2449). No one reported acquired injuries, and only 1 reported being at risk of injury. Conclusions We found low risk of physical injury reported by volunteer citizen responders dispatched to out-of-hospital cardiac arrest. Risk of injury should be considered and monitored as a safety measure in citizen responder programs.