Impact of dispatcher-assisted cardiopulmonary resuscitation policy on outcomes following out-of-hospital cardiac arrest: an interrupted time series analysis.
Resuscitation · 2025-09-12 · Quasi-experimental
Abstract
BACKGROUND: Despite the increasing adoption of dispatcher-assisted Cardiopulmonary Resuscitation (DA-CPR), evidence on its efficacy remains relatively scarce in developing countries. This interrupted time-series study assessed the impact of the DA-CPR policy on Out-of-hospital cardiac arrest (OHCA) outcomes in Shanghai, with the aim of informing evidence-based improvements in emergency care systems. METHODS: This study analyzed OHCA data reported by the Shanghai Medical Emergency Center from January 2019 to July 2024. Joinpoint regression analysis was used to identify and adjust for the impact of COVID-19 on OHCA outcomes. A modified autoregressive integrated moving average (ARIMA) model was used to quantify changes in outcomes before and after the implementation of the DA-CPR policy. Counterfactual analysis simulated OHCA outcomes trajectories without the policy, providing visual demonstration of the policy's effects. RESULTS: Among 75,628 OHCA cases (median age 85), annual OHCA incidence ranged from 144 to 287 per 100,000 population, with age-standardized rates of 60 to 105. The average bystander CPR rate was 4.643% (age-standardized: 10.554%), the average ROSC rate was 2.914% (age-standardized: 4.799%), and the 30-day survival rate was 0.376% (age-standardized: 1.379%). Time-series analysis showed a significant post-policy level increase of 3.553 percentage point in bystander CPR (95% CI 1.227-5.879, P < 0.05), 2.215 percentage point in ROSC (95% CI 1.052-3.380, P < 0.001) and 0.461 percentage point in 30-day survival (95% CI 0.025-0.898, P < 0.05). CONCLUSIONS: DA-CPR implementation substantially improved OHCA outcomes in Shanghai, supporting its adoption in developing countries to optimize emergency care outcomes.