Association of Bystander Interventions With Neurologically Intact Survival Among Patients With Bystander-Witnessed Out-of-Hospital Cardiac Arrest in Japan

Abstract

IMPORTANCE Neurologically intact survival after out-of-hospital cardiac arrest (OHCA) has been increasing in Japan. However, associations between increased prehospital care, including bystander interventions and increases in survival, have not been well estimated. OBJECTIVE To estimate the associations between bystander interventions and changes in neurologically intact survival among patients with OHCA in Japan. DESIGN, SETTING, AND PARTICIPANTS Retrospective descriptive study using data from Japan's nationwide OHCA registry, which started in January 2005. The registry includes all patients with OHCA transported to the hospital by emergency medical services (EMS) and recorded patients' characteristics, prehospital interventions, and outcomes. Participants were 167 912 patients with bystander-witnessed OHCA of presumed cardiac origin in the registry between January 2005 and December 2012. EXPOSURES Prehospital interventions by bystander, including defibrillation using public-access automated external defibrillators and chest compression. MAIN OUTCOMES AND MEASURES Neurologically intact survival was defined as Glasgow-Pittsburgh cerebral performance category score 1 or 2 and overall performance category scores 1 or 2 at 1 month or at discharge. The association between the interventions and neurologically intact survival was evaluated. RESULTS From 2005 to 2012, the number of bystander-witnessed OHCAs of presumed cardiac origin increased from 17 882 (14.0 per 100 000 persons [95% CI, 13.8-14.2]) to 23 797 (18.7 per 100 000 persons [95% CI, 18.4-18.9]), and neurologically intact survival increased from 587 cases (age-adjusted proportion, 3.3% [95% CI, 3.0%-3.5%]) to 1710 cases (8.2% [95% CI, 7.8%-8.6%]). The rates of bystander chest compression increased from 38.6% to 50.9%, bystander-only defibrillation increased from 0.1% to 2.3%, bystander defibrillation combined with EMS defibrillation increased from 0.1% to 1.4%, and EMS-only defibrillation decreased from 26.6% to 23.5%. Performance of bystander chest compression, compared with no bystander chest compression, was associated with increased neurologically intact survival (8.4% [6594 survivors/78 592 cases] vs 4.1% [3595 survivors/88 720 cases]; odds ratio [OR], 1.52 [95% CI, 1.45-1.60]). Compared with EMS-only defibrillation (15.0% [6445 survivors/42 916 cases]), bystander-only defibrillation (40.7% [931 survivors/2287 cases]) was associated with increased neurologically intact survival (OR, 2.24 [95% CI, 1.93-2.61]), as was combined bystander and EMS defibrillation (30.5% [444 survivors/1456 cases]; OR, 1.50 [95% CI, 1.31-1.71]), whereas no defibrillation (2.0% [2369 survivors/120 653 cases]) was associated with reduced survival (OR, 0.43 [95% CI, 0.39-0.48]). CONCLUSIONS AND RELEVANCEIn Japan, between 2005 and 2012, the rates of bystander chest compression and bystander defibrillation increased and were associated with increased odds of neurologically intact survival.

Multistate 5‐Year Initiative to Improve Care for Out‐of‐Hospital Cardiac Arrest: Primary Results From the HeartRescue Project

“…We observed bystander CPR in excess of 40% among all rhythm arrests and approaching 60% in the Utstein subgroup, results that surpass other North American and Asian reports and that compare favorably to European experiences 23, 24, 25. We also observed modest temporal improvements in bystander CPR; however, the increase in bystander CPR was more modest than other programmatic initiatives that have corresponded to outcome improvements 26, 27, 28. The rate of bystander AED increased over time, reaching 5% among all arrests and nearly 9% in the Utstein subgroup.…”

Relationship Between Emergency Medical Services Response Time and Bystander Intervention in Patients With Out‐of‐Hospital Cardiac Arrest

“…To increase the rates of bystander intervention before the arrival of EMS personnel, several strategies have been implemented in industrialized nations: traditional classroom training, dispatcher‐guided CPR, school‐based instruction, online education, and targeted neighborhood or individualized training 4, 7, 8, 9, 24, 25, 26, 27, 28, 29, 30. Despite these strategies and the increase in rates of bystander intervention, the rate of neurologically intact survival cannot improve if the EMS response time is too long.…”

“…However, the proportion of patients who receive bystander CPR, following an out‐of‐hospital cardiac arrest (OHCA), is still relatively low in most countries 3. Fortunately, bystander CPR rates in some countries have recently increased to ≈50% 4, 5, 6, 7, 8, 9. In an analysis of OHCA, Hasselqvist‐Ax and colleagues6 reported survival that was more than twice as high among patients who received bystander CPR compared with those who received no CPR before the arrival of emergency medical services (EMS) providers.…”

Survival From Out‐of‐Hospital Cardiac Arrest: Are We Beginning to See Progress?

“…There are ample data in the literature to suggest that bystander CPR and public AED application can increase survival. Nakahara et al reviewed the OHCA data in Japan from 2005 to 2007, analyzing data from >167 000 bystander‐witnessed OHCAs of cardiac origin 3. They evaluated the incidence of bystander prehospital intervention and specifically reviewed neurologically intact survival at 1 month and at discharge.…”