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).