Outcomes differ by first documented rhythm after witnessed out-of-hospital cardiac arrest in children: An observational study with prospective nationwide population-based cohort database in Japan

Aims To evaluate and compare outcomes and impacts of delay of time to cardiopulmonary resuscitation (CPR) by type of first documented rhythm in paediatric patients with out-of-hospital cardiac arrest (OHCA). Methods and results We enrolled 3968 paediatric (aged,18 years) OHCA patients whose events were witnessed between 2005 and 2012 from a prospective nationwide population-based cohort database in Japan. We assessed and compared their neurologically favourable 1-month survival according to first documented rhythm: pulseless ventricular tachycardia/ventricular fibrillation (pVT/VF), pulseless electrical activity (PEA), or asystole. Out-of-hospital cardiac arrest patients with pVT/ VF, PEA, and asystole totalled 556 (14.0%), 1249 (31.5%), and 2163 (54.5%), respectively. The proportion of overall neurologically favourable 1-month survival in patients with pVT/VF, PEA, and asystole was 36.5, 5.0, and 1.8%, respectively, in the entire study population, and 73.8, 27.7, and 13.8%, respectively, in patients who achieved pre-hospital return of spontaneous circulation (ROSC). As the time from collapse to CPR lengthened, the number of patients with asystole increased, whereas those of pVT/VF and PEA decreased (P, 0.001). After paediatric OHCA, earlier initiation of CPR resulted in higher rates of pre-hospital ROSC (adjusted odds ratio 0.97, 95% confidence interval 0.95–0.99, P ¼ 0.018), which led to much better patient outcomes than in the total study population. Conclusion We confirmed that pVT/VF and early ROSC in general were associated with better outcomes in patients with witnessed paediatric OHCA.