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Persons who witness an out-of-hospital cardiac arrest (OHCA)—that is, bystanders—have the capacity to institute essential, primary steps of resuscitation, including cardiopulmonary resuscitation (CPR) and defibrillation with an automatic external defibrillator (AED). Bystander resuscitation comprises the first 3 links in the chain of survival, a series of interventions sequenced to save the lives of patients who experience an OHCA. Broadly defined, community interventions aiming to enhance bystander CPR and AED education have been associated with improved rates of bystander involvement and improved OHCA outcomes.^1,2 Recognizing that OHCA survival has been an active area of investigation for more than 50 years, promoting effective OHCA bystander intervention is, therefore, an important global health initiative.³ Although studies of such community-level educational interventions have yielded differing effect estimates, programs with longevity portend more bystander participation and better OHCA outcomes in systematic review and meta-analyis.⁴

Li et al⁵ evaluated the impact of the Emergency Medical Aid Act, a novel piece of legislation operationalizing public basic life support training (ie, CPR training and AED deployment) in China. Standardized CPR and AED instruction was provisioned yearly to health care workers, public transit employees, students, and the general public. The act also conferred legal protection for bystanders, analogous to a Good Samaritan law. The authors leveraged data from Shenzhen, China, an area of approximately 17.5 million people, which was reportedly the first among several pilot cities to develop relevant educational interventions and maintained a robust, longitudinal OHCA registry.⁶ Rates of bystander-initiated CPR and AED use were examined as primary outcomes before (January 1, 2010, to September 30, 2018) and after (October 1, 2018, to December 31, 2022) the enactment of legislation via interrupted time-series analysis. Relevant measures, such as survival to hospital admission and discharge, were examined as secondary outcomes. The authors report improved rates of bystander CPR, bystander AED use, and prehospital return of spontaneous circulation after the establishment of the Emergency Medical Aid Act.⁵ Despite these accomplishments, however, multivariable gaussian regression revealed no statistically significant changes in survival to hospital discharge.

The authors⁵ demonstrated that Shenzhen’s initiatives in the context of a broader legislative framework increased rates of bystander intervention in OHCA, and their efforts should be commended. Even with this important development, we are reminded that the objective of improving bystander participation in OHCA is not to augment rates of return of spontaneous circulation in isolation. The goal of prehospital resuscitative efforts is to bolster sustained rates of neurologically favorable discharge from the hospital, often measured by scores such as Cerebral Performance Categories and/or the Modified Rankin Scale.

The reason for the potential discrepancy in hospital discharge rates seen by the authors and those seen in comparable works is undeniably multifactorial. Investigations describing the association of legal provisions for bystander education with outcomes are often externally invalid given that each system (eg, country, state, or city) leverages distinct mechanisms and resources for implementing bystander instruction. In addition, most investigations are unable to quantify the impact of scientific progress made during observation periods. For example, findings from study periods spanning disparate OHCA management practice patterns (eg, targeted temperature management or coronary angiography) may be confounded by these factors, complicating interpretations.

The survival of a patient sustaining OHCA is, to a certain extent, predicated on the tensile strength of each link in the chain of survival. Systems have reported improved outcomes of OHCA over the past decades, identifying several nodes contributing to success.⁷ The outcomes reported by Li et al⁵ suggest that efforts to improve bystander performance should be met with a commensurate in-hospital focus to optimize OHCA outcomes—an equivalently challenging arena to address. In resource-limited settings, a generalizable next step from this investigation is to ensure accessible, durable, in-hospital processes evidenced to improve OHCA outcomes. Longitudinal registries, such as the one used in this investigation, should ideally record both system-relevant (eg, bystander intervention) and patient-centered (eg, neurological assessments) data points to inform future policy.

One take-home message from this investigation is the importance of investing in systems of care. Decades of OHCA investigation have undoubtedly highlighted the importance of high-quality bystander intervention. The initial links in the chain of survival are facilitated and improved by such emerging innovations alongside developing systems, supporting all links in the chain.

Published: April 26, 2024. doi:10.1001/jamanetworkopen.2024.7890

Open Access: This is an open access article distributed under the terms of the CC-BY License. © 2024 Hockstein MA. ÁñÁ«ÊÓƵ Network Open.

Corresponding Author: Maxwell A. Hockstein, MD, MS, Department of Emergency Medicine, Department of Critical Care, Georgetown University School of Medicine, MedStar Washington Hospital Center, 110 Irving St NW, Washington, DC 20010 (max.hockstein@gmail.com).

Conflict of Interest Disclosures: None reported.