Decreasing the time to defibrillation: A comparative study of defibrillator electrode designs

Introduction: Time to defibrillation (T_defib) is the most important modifiable factor affecting survival from cardiac arrest. Mortality increases by approximately 7-10% for each minute of defibrillation delay. The purpose of this study was to determine whether defibrillator electrode design complexity affects T_defib. Methods: This was a randomized sequential design study utilizing a standardized ventricular fibrillation cardiac arrest model for CPR mannequins. We evaluated two common types of defibrillator electrode models: a single connector design and a double connector design that requires an adaptor. We compared the time required by cardiac arrest team leaders to apply the two types of defibrillator electrodes to a manikin, connect them to a defibrillator, and then deliver a first defibrillatory shock. The primary outcome was time to defibrillation. The secondary outcome was difficulty of application as perceived by the physician participants on a 10 cm visual analog scale. Results: Thirty-two residents performed a sequential assessment of both electrodes. The average T_defib for the double connector model was 42.9 s longer than that of the single connector model (87.5 s versus 44.6 s, p < 0.001). As evaluated by the study participants, the single connector model was significantly easier to apply then the double connector model (1.3 cm versus 4.4 cm, p < 0.001). Conclusion: The single connector defibrillator electrode design was associated with a significantly shorter T_defib than the double connector design. It also was judged to be easier to apply in this model. Ergonomic design of defibrillator electrodes can significantly impact time to defibrillation.