Trends in the incidence and outcome of paediatric out-of-hospital cardiac arrest: A 17-year observational study

Background: System-based improvements to the chain of survival have yielded increases in survival from out-of-hospital cardiac arrest (OHCA) in adults. Comparatively little is known about the long-term trends in incidence and survival following paediatric OHCA. Methods: Between 2000 and 2016, we included children aged <= 16 years who suffered a non-traumatic OHCA in the state of Victoria, Australia. Trends in incidence and unadjusted outcomes were assessed using linear regression and a non-parametric test for trend. Multivariable logistic regression with multiple imputation was used to identify arrest factors associated with event survival and survival to hospital discharge. Results: Of the 1301 paediatric OHCA events attended by emergency medical services (EMS), 948 (72.9%) received an attempted resuscitation. The overall incidence of EMS-attended and EMS-treated events was 6.7 and 4.9 cases per 100,000 person-years, with no significant changes in trend. Although the proportion of cases with OHCA identified in the call and receiving bystander CPR increased over time, EMS response times also increased. Unadjusted event survival rose from 23.3% in 2000 to 33.3% in 2016 (p trend = .007), and survival to hospital discharge rose from 9.4% to 17.7% over the same period (p trend = .04). Increases in survival to hospital discharge were largely driven by initial shockable arrests, which rose from 33.3% in 2000 to 60.0% in 2016 (p trend = .005). Survival after initial shockable arrests was higher if the first shock was delivered by either first responder or public AED compared with paramedics (83.3% vs. 40.0%, p = .04). After adjustment, the odds of event survival and survival to hospital discharge increased independent of baseline characteristics, by 7% (OR 1.07, 95% CI: 1.03, 1.11; p = .001) and 8% (OR 1.08, 95% CI: 1.01, 1.15; p = .02) per study year, respectively. Conclusions: Survival following paediatric OHCA increased in our region over a 17 year period. This was driven, in part, by improving outcomes for initial shockable arrests.