Dispatcher-assisted AED use in single-rescuer cardiac arrest: study protocol for a randomized simulation study comparing standard and optimized dispatcher-assisted CPR instructions.

BACKGROUND

Although automated external defibrillators (AEDs) improve outcomes in shockable rhythms, their use introduces interruptions in chest compressions. In single-rescuer scenarios, AED retrieval and application may further increase no-flow time. The effect of dispatcher instruction strategy on these interruptions remains unclear. This study aims to evaluate whether AED-optimized dispatcher-assisted CPR (DACPR) instructions reduce no-flow time compared with standard instructions in a simulated single-rescuer OHCA setting.

METHODS

This prospective, randomized, controlled, parallel-group simulation trial will include adult laypersons and healthcare professionals. Participants will be allocated in a 1:1 ratio to either standard or AED-optimized DACPR instruction groups. All scenarios will be conducted in a controlled simulation environment with standardized AED accessibility (≤1 min retrieval distance) to isolate the effect of dispatcher communication on CPR performance. The primary outcome will be total no-flow time. Secondary outcomes include chest compression fraction, time to first compression, time to first shock, peri-shock pauses, and CPR quality metrics.

DISCUSSION: This study investigates dispatcher instruction as a modifiable determinant of CPR interruption during AED use in single-rescuer scenarios. Findings will provide mechanistic insight into how communication strategies influence CPR quality under controlled conditions and may inform refinement of DACPR protocols.

ETHICS AND DISSEMINATION: The study protocol was approved by the Institutional Ethics Committee of the University of Pécs (PTE/87175-1/2025). Written informed consent will be obtained. Results will be disseminated via peer-reviewed publication and scientific conferences.

TRIAL REGISTRATION: ClinicalTrials.gov: NCT07520877, prospectively registered on 8 April 2026.