Detection of gasping through transthoracic impedance: a new approach to early cardiac arrest recognition

Timely recognition of cardiac arrest (CA) is often delayed because gasping, a frequent sign of CA, is misinterpreted as normal breathing. In a porcine model of untreated CA with frequent gasps, we tested whether transthoracic impedance (TTI), continuously measured through defibrillator pads, could capture gasping-related thoracic volume changes. Gasping-induced inspiratory efforts produced large, distinctive TTI fluctuations. This observation was then confirmed in a healthy human volunteer simulating gasping under open and closed airway conditions. These translational findings support automated, TTI-based gasping detection via automated external defibrillators as a feasible strategy to improve early CA recognition and accelerate bystander CPR initiation.