Prediction model for future OHCAs based on geospatial and demographic data: An observational study.

This study used demographic data in a novel prediction model to identify areas with high risk of out-of-hospital cardiac arrest (OHCA) in order to target prehospital preparedness. We combined data from the nationwide Danish Cardiac Arrest Registry with geographical- and demographic data on a hectare level. Hectares were classified in a hierarchy according to characteristics and pooled to square kilometers (km2). Historical OHCA incidence of each hectare group was supplemented with a predicted annual risk of at least 1 OHCA to ensure future applicability. We recorded 19,090 valid OHCAs during 2016 to 2019. The mean annual OHCA rate was highest in residential areas with no point of public interest and 100 to 1000 residents per hectare (9.7/year/km2) followed by pedestrian streets with multiple shops (5.8/year/km2), areas with no point of public interest and 50 to 100 residents (5.5/year/km2), and malls with a mean annual incidence per km2 of 4.6. Other high incidence areas were public transport stations, schools and areas without a point of public interest and 10 to 50 residents. These areas combined constitute 1496 km2 annually corresponding to 3.4% of the total area of Denmark and account for 65% of the OHCA incidence. Our prediction model confirms these areas to be of high risk and outperforms simple previous incidence in identifying future risk-sites. Two thirds of out-of-hospital cardiac arrests were identified in only 3.4% of the area of Denmark. This area was easily identified as having multiple residents or having airports, malls, pedestrian shopping streets or schools. This result has important implications for targeted intervention such as automatic defibrillators available to the public. Further, demographic information should be considered when implementing such interventions.

Volunteer Responder Interventions in Out-of-Hospital Cardiac Arrest in Urban, Suburban, and Rural Areas.

BACKGROUND: Patients with out-of-hospital cardiac arrest (OHCA) in rural areas experience longer emergency response times and have lower survival rates compared with patients in urban areas. Volunteer responders might improve care and outcomes for patients with OHCA specifically in rural areas. Therefore, we investigated volunteer responder interventions based on the degree of urbanization. METHODS AND RESULTS: We included 1310 OHCAs from 3 different regions in Denmark where volunteer responders had arrived at the OHCA location. The location was classified as urban, suburban, or rural according to the Eurostat Degree of Urbanization Tool. A logistic regression model was used to examine associations between the degree of urbanization and volunteer responder arrival before emergency medical services, cardiopulmonary resuscitation, or defibrillation. We found the odds for volunteer responder arrival before emergency medical services more than doubled in rural areas (odds ratio [OR], 2.60 [95% CI, 1.91-3.53]) and suburban areas (OR, 2.05 [95% CI, 1.56-2.69]) compared with urban areas. In OHCA cases where volunteer responders arrived first, odds for bystander cardiopulmonary resuscitation was tripled in rural areas (OR, 3.83 [95% CI, 1.64-8.93]) and doubled in suburban areas (OR, 2.27 [95% CI, 1.17-4.41]) compared with urban areas. Bystander defibrillation was more common in suburban areas (OR, 1.53 [95% CI, 1.02-2.31]), where almost 1 out of 4 patients received bystander defibrillation, compared with urban areas. CONCLUSIONS: Volunteer responders are significantly more likely to arrive before emergency medical services in rural and suburban areas than in urban areas. Patients with OHCA received more cardiopulmonary resuscitation in rural and suburban areas and more defibrillation in suburban areas than in urban areas.

Association of Degree of Urbanization and Survival in Out-of-Hospital Cardiac Arrest.

Background Survival from out-of-hospital cardiac arrest (OHCA) varies across regions. The aim of this study was to evaluate the association between urbanization (rural, suburban, and urban areas), bystander interventions (cardiopulmonary resuscitation and defibrillation), and 30-day survival from OHCAs in Denmark. Methods and Results We included OHCAs not witnessed by ambulance staff in Denmark from January 1, 2016, to December 31, 2020. Patients were divided according to the Eurostat Degree of Urbanization Tool in rural, suburban, and urban areas based on the 98 Danish municipalities. Poisson regression was used to estimate incidence rate ratios. Logistic regression (adjusted for ambulance response time) tested differences between the groups with respect to bystander interventions and survival, according to degree of urbanization. A total of 21 385 OHCAs were included, of which 8496 (40%) occurred in rural areas, 7025 (33%) occurred in suburban areas, and 5864 (27%) occurred in urban areas. Baseline characteristics, as age, sex, location of OHCA, and comorbidities, were comparable between groups. The annual incidence rate ratio of OHCA was higher in rural areas (1.54 [95% CI, 1.48-1.58]) compared with urban areas. Odds for bystander cardiopulmonary resuscitation were lower in suburban (0.86 [95% CI, 0.82-0.96]) and urban areas (0.87 [95% CI, 0.80-0.95]) compared with rural areas, whereas bystander defibrillation was higher in urban areas compared with rural areas (1.15 [95% CI, 1.01-1.31]). Finally, 30-day survival was higher in suburban (1.13 [95% CI, 1.02-1.25]) and urban areas (1.17 [95% CI, 1.05-1.30]) compared with rural areas. Conclusions Degree of urbanization was associated with lower rates of bystander defibrillation and 30-day survival in rural areas compared with urban areas.

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.