Decline in Rescue Breathing and Its Impact on Outcomes in Pediatric Out-of-Hospital Cardiac Arrest Due to Drowning: A Nationwide Study, 2012–2023

BackgroundRescue breathing is considered essential in pediatric out-of-hospital cardiac arrest (OHCA) due to drowning, a type of asphyxial arrest where hypoxia precedes circulatory collapse.However, the increasing promotion of compression-only CPR (CO-CPR) may have contributed to changes in bystander CPR practices, including a decline in rescuebreathing CPR (RB-CPR).Whether such temporal changes have influenced outcomes in pediatric drowning OHCA remains unclear. MethodsWe analyzed nationwide data from the All-Japan Utstein Registry (2012-2023), including pediatric OHCA patients (17 years old) whose arrests were caused by drowning and received bystander CPR from laypersons.Patients were categorized into RB-CPR and CO-CPR groups.The primary outcome was 30-day mortality; secondary outcomes included prehospital absence of return of spontaneous circulation (ROSC) and 30-day unfavorable neurological survival, defined as Cerebral Performance Category score 3-5.We used multivariable Poisson regression to estimate adjusted risk ratio (aRR) and conducted analyses by age and witnessed status. ResultsAmong 740 eligible patients, 41.6% received RB-CPR and 58.4% received CO-CPR.The proportion of RB-CPR declined over the study period.CO-CPR was associated with higher 30-day mortality (aRR 1.38, 95% CI 1.14-1.67),higher prehospital absence of ROSC, and worse neurological outcomes compared with RB-CPR.The adverse association of CO-CPR was most pronounced in unwitnessed arrests, where ventilation may be particularly important. ConclusionsIn pediatric drowning OHCA, CO-CPR was associated with worse survival and neurological outcomes than RB-CPR.These findings underscore the necessity for rescue breathing and the importance of ventilation-focused bystander CPR training in pediatric and drowning-related scenarios.