ObjectiveIt remains unknown whether patient socioeconomic factors affect interventions and survival after out-of-hospital cardiac arrest (OHCA), and whether a socioeconomic effect on bystander interventions affects survival. Therefore, this study examined patient socioeconomic disparities in prehospital factors and survival.MethodsFrom the Danish Cardiac Arrest Registry, patients with OHCA ≥30 years were identified, 2001–2014, and divided into quartiles of household income (highest, high, low, lowest). Associations between income and bystander cardiopulmonary resuscitation (CPR) and 30-day survival with bystander CPR as mediator were analysed by logistic regression and mediation analysis in private witnessed, public witnessed, private unwitnessed and public unwitnessed arrests, adjusted for confounders.ResultsWe included 21 480 patients. Highest income patients were younger, had higher education and were less comorbid relative to lowest income patients. They had higher odds for bystander CPR with the biggest difference in private unwitnessed arrests (OR 1.74, 95% CI 1.47 to 2.05). For 30-day survival, the biggest differences were in public witnessed arrests with 26.0% (95% CI 22.4% to 29.7%) higher survival in highest income compared with lowest income patients. Had bystander CPR been the same for lowest income as for highest income patients, then survival would be 25.3% (95% CI 21.5% to 29.0%) higher in highest income compared with lowest income patients, resulting in elimination of 0.79% (95% CI 0.08% to 1.50%) of the income disparity in survival. Similar trends but smaller were observed in low and high-income patients, the other three subgroups and with education instead of income. From 2002 to 2014, increases were observed in both CPR and survival in all income groups.ConclusionOverall, lower socioeconomic status was associated with poorer prehospital factors and survival after OHCA that was not explained by patient or cardiac arrest-related factors.

ObjectiveTo examine the association between time from emergency medical service vehicle dispatch to hospital arrival and 1-day and 30-day mortality.DesignRegister-based cohort study.SettingNorth Denmark Region (≈8000 km2, catchment population ≈600 000).ParticipantsWe included all highest priority dispatched ambulance transports in North Denmark Region in 2006–2012.InterventionsUsing logistic regression and the g-formula approach, we examined the association between time from emergency dispatch to hospital arrival and mortality for presumed heart, respiratory, cerebrovascular and other presumed medical conditions, as well as traffic or other accidents, as classified by emergency dispatch personnel.Main outcome measures1-day and 30-day mortality.ResultsAmong 93 167 individuals with highest priority ambulances dispatched, 1948 (2.1%) were dead before the ambulance arrived and 19 968 (21.4%) were transported to the hospital under highest priority (median total prehospital time from dispatch to hospital arrival 47 min (25%–75%: 35–60 min); 95th percentile 84 min). Among 18 709 with population data, 1-day mortality was 10.9% (n=2038), and was highest for patients with dyspnoea (20.4%) and lowest for patients with traffic accidents (2.8%). Thirty-day mortality was 18.3% and varied between 36.6% (patients with dyspnoea) and 3.7% (traffic accidents). One-day mortality was not associated with total prehospital time, except for presumed heart conditions, where longer prehospital time was associated with decreased mortality: adjusted OR for >60 min vs 0–30 min was 0.61 (95% CI 0.40 to 0.91). For patients with dyspnoea, OR for >60 min vs 0–30 min was 0.90 (95% CI 0.56 to 1.45), for presumed cerebrovascular conditions OR 1.41 (95% CI 0.53 to 3.78), for other presumed medical conditions OR 0.84 (95% CI 0.70 to 1.02), for traffic accidents OR 0.65 (95% CI 0.29 to 1.48) and for other accidents OR 0.84 (95% CI 0.47 to 1.51). Similar findings were found for 30-day mortality.ConclusionsIn this study, where time from emergency dispatch to hospital arrival mainly was <80 min, there was no overall relation between this prehospital time measure and mortality.

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Aim: To examine incidence and outcome following out-of-hospital cardiac (OHCA) arrest in a high-risk area characterised by high density of potential bystanders and easy access to nearby automated external defibrillators (AEDs). Methods: This retrospective observational study investigated pre-hospital and in-hospital treatment, as well as survival amongst persons with OHCA at Copenhagen International Airport between May 25, 2015 and May 25, 2019. OHCA data from pre-and in-hospital medical records were obtained and compared with public bystander witnessed OHCAs in Denmark. Results: Of the 23 identified non-traumatic OHCAs, 91.3% were witnessed by bystanders, 73.9% received bystander cardiopulmonary resuscitation (CPR), and 43.5% were defibrillated by a bystander. Survival to hospital discharge was 56.5%, with 100% survival among persons with an initial shockable heart rhythm. Compared with nationwide bystander witnessed OHCAs, persons with OHCA at the airport were less likely to receive bystander CPR (73.9% vs. 89.4%, OR 0.33; 95% CI, 0.13À0.86), more likely to receive bystander defibrillation (43.5% vs. 24.8%, OR 2.32; 95% CI, 1.01À5.31), to achieve return of spontaneous circulation (78.2% vs. 50.6%, OR 3.51; 95% CI, 1.30À9.49), and survive to hospital discharge (56.5% vs. 45.2%, OR 1.58; 95% CI, 0.69À3.62). Conclusion: We found a high proportion of bystander defibrillation indicating that bystanders will quickly apply an AED, when accessible. Importantly, 56% of all persons, and all persons with a shockable heart rhythm survived. These findings suggest increased potential for survival following OHCA and support current guidelines to strategically deploy accessible AEDs in high-risk OHCA areas.