Effect of AED-optimized Telephone-assisted CPR Instructions on No-flow Time and Chest Compression Fraction

Out-of-hospital cardiac arrest (OHCA) remains a leading cause of mortality worldwide, with survival highly dependent on the immediate initiation of bystander cardiopulmonary resuscitation (CPR). Early recognition, prompt chest compressions, and rapid defibrillation are critical components of the chain of survival. Telephone-assisted CPR (T-CPR) provided by emergency dispatchers has been shown to significantly increase bystander intervention rates and improve outcomes. While the availability and use of automated external defibrillators (AEDs) further enhance survival, the optimal integration of AED use into dispatcher-guided, single-rescuer scenarios remains insufficiently studied. This prospective, randomized, controlled simulation study aims to evaluate the effect of modified telephone cardiopulmonary resuscitation (T-CPR) instructions optimized for automated external defibrillator (AED) use on no-flow time and chest compression fraction (CCF) during single-rescuer resuscitation. Participants are randomized to receive either standard T-CPR instructions or enhanced instructions focusing on minimizing interruptions in chest compressions and reducing time to first compression during AED use.