Decline in rescue breathing and its impact on outcomes in pediatric out-of-hospital cardiac arrest due to drowning: a nationwide study, 2012–2023

Background: Rescue 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 rescue-breathing CPR (RB-CPR). Whether such temporal changes have influenced outcomes in pediatric drowning OHCA remains unclear.
Methods: We 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.
Results: Among 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.
Conclusions: In 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.