Successful dispatcher-assisted CPR and outcomes after out-of-hospital cardiac arrest: an age-specific nationwide study.

BACKGROUND: Dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) is an essential strategy for increasing bystander CPR and improving outcomes after out-of-hospital cardiac arrest (OHCA). However, evidence comparing the effectiveness of successful DA-CPR in adult and pediatric populations remains limited. This study evaluated the association between successful DA-CPR and clinical outcomes after OHCA in adult and pediatric patients and assessed whether age modified these associations. METHODS: Emergency medical service (EMS)-treated non-traumatic OHCA cases recorded in the nationwide Korean Out-of-Hospital Cardiac Arrest Registry between 2012 and 2021 were analyzed. DA-CPR was classified as successful or unsuccessful according to dispatcher documentation. Patients were categorized a priori as adult (≥18 years) or pediatric (<18 years), and a four-category exposure variable combining age group and DA-CPR status was constructed. The primary outcome was survival to hospital discharge. Multivariable logistic regression models were used to estimate associations between successful DA-CPR and outcomes, including an interaction term between age group and DA-CPR status. RESULTS: A total of 90,931 patients who received DA-CPR instructions before EMS arrival were included. Successful DA-CPR was independently associated with increased odds of survival to hospital discharge in both adults (adjusted odds ratio [aOR] 1.67, 95% confidence interval [CI] 1.55-1.79) and pediatric patients (aOR 1.91, 95% CI 1.21-3.01). No significant interaction was observed between age group and DA-CPR status (P = 0.56). Sensitivity analyses yielded similar results. CONCLUSION: Successful DA-CPR was associated with improved survival outcomes in both adult and pediatric patients with OHCA, with no evidence of effect modification by age.