Lancet Public Health. 2026 Nov;11(11):e878-e888. doi: 10.1016/S2468-2667(26)00200-8.
ABSTRACT
BACKGROUND: Bystander cardiopulmonary resuscitation (CPR) is a key determinant of survival after out-of-hospital cardiac arrest (OHCA), but rates remain suboptimal worldwide. We evaluated whether a multifaceted intervention targeting emergency dispatch systems and community response could increase bystander-initiated CPR before emergency medical service (EMS) arrival.
METHODS: We conducted a stepped-wedge, cluster-randomised trial in 15 French EMS agencies. The intervention combined dispatcher training for early recognition of cardiac arrest and telephone-assisted CPR, activation of trained volunteers through a geolocation smartphone application, and structured audit and feedback provided to EMS agencies. Consecutive adults (≥18 years) with non-traumatic OHCA were included. Randomisation was stratified by tercile of OHCA volume managed by each EMS in 2015. The intervention was implemented during a 1-month transition period before the intervention period at each EMS centre. A dedicated protocol guided dispatchers to identify cardiac arrest from unresponsiveness and abnormal breathing, then gave scripted compression-only instructions and activated volunteers, targeting recognition within 60 s of call pick-up and first compression within a further 60 s. The primary outcome was bystander-initiated CPR before EMS arrival. The trial was prospectively registered on ClinicalTrials.gov (NCT03633370) and is completed.
FINDINGS: Of the 15 EMS agencies initially randomised, two withdrew before recruitment began and were replaced, and one enrolled no patients. Therefore, between Aug 27, 2018, and Feb 20, 2022, 14 EMS agencies recruited a total of 2160 patients. The intention-to-treat analysis included 1684 patients (686 control, 998 intervention) enrolled across the 12 originally randomised EMS agencies. The mean age for all patients included in the intention-to-treat analysis was 67 years (SD 15), and 1205 (71·6%) were male. Bystander-initiated CPR before EMS arrival occurred in 421 (61·4%) patients in the control group and 708 (70·9%) patients in the intervention group (adjusted odds ratio [OR] 1·54 [95% CI 1·09-2·19]; p=0·017). Estimates were consistent across six prespecified sensitivity analyses (OR range, 1·38-1·55), remaining significant in four, but not after adjustment for cluster-specific secular trends (1·38 [0·98-1·94]) or baseline characteristics (1·39 [0·97-1·98]). No intervention-related adverse events were reported.
INTERPRETATION: A multifaceted intervention was associated with increased bystander-initiated CPR after OHCA, although the estimate was sensitive to the modelling of secular trends, and it did not translate into improved clinical outcomes. These findings support further investigation of coordinated community-based strategies to strengthen the early links in the chain of survival at a population level.
FUNDING: Direction Générale de l’Offre de Soins.
PMID:42901186 | DOI:10.1016/S2468-2667(26)00200-8
