Alert system-supported lay defibrillation and basic life-support for cardiac arrest at home

Abstract

Abstract Aims Automated external defibrillators (AEDs) are placed in public, but the majority of out-of-hospital cardiac arrests (OHCA) occur at home. Methods and results In residential areas, 785 AEDs were placed and 5735 volunteer responders were recruited. For suspected OHCA, dispatchers activated nearby volunteer responders with text messages, directing two-thirds to an AED first and one-third directly to the patient. We analysed survival (primary outcome) and neurologically favourable survival to discharge, time to first defibrillation shock, and cardiopulmonary resuscitation (CPR) before Emergency Medical Service (EMS) arrival of patients in residences found with ventricular fibrillation (VF), before and after introduction of this text-message alert system. Survival from OHCAs in residences increased from 26% to 39% {adjusted relative risk (RR) 1.5 [95% confidence interval (CI): 1.03–2.0]}. RR for neurologically favourable survival was 1.4 (95% CI: 0.99–2.0). No CPR before ambulance arrival decreased from 22% to 9% (RR: 0.5, 95% CI: 0.3–0.7). Text-message-responders with AED administered shocks to 16% of all patients in VF in residences, while defibrillation by EMS decreased from 73% to 39% in residences (P < 0.001). Defibrillation by first responders in residences increased from 22 to 40% (P < 0.001). Use of public AEDs in residences remained unchanged (6% and 5%) (P = 0.81). Time from emergency call to defibrillation decreased from median 11.7 to 9.3 min; mean difference –2.6 (95% CI: –3.5 to –1.6). Conclusion Introducing volunteer responders directed to AEDs, dispatched by text-message was associated with significantly reduced time to first defibrillation, increased bystander CPR and increased overall survival for OHCA patients in residences found with VF. Key Question The Emergency Medical Service introduced a text-message alert system to alert volunteers close to an out-of-hospital cardiac arrest patient. In addition, 785 automated external defibrillators (AEDs) were added and made available in the community. Does adding this system result in more basic life support (BLS), earlier defibrillation, and better survival? Key Finding We found that BLS increased from 78% to 91%, the time from emergency call to the first defibrillation shock decreased by 2.6 min and survival for patients at home, and found in ventricular fibrillation, increased from 26% to 39%. Take Home Message For patients with a cardiac arrest at home, an alert system that includes nearby volunteers activated by the ambulance dispatch centre and many easily accessible AEDs really saves lives. Implementation is an effective community effort.