Time to defibrillation: a controlled laboratory study comparing three automated and semi-automated defibrillators

Currently there are three vendors marketing first-responder defibrillation units. Each vendor's unit has its own distinct features, advantages, and disadvantages, making the selection of one vendor's unit a complex decision. However, two critical performance criteria upon which a decision to choose one vendor's unit over another could be 1) differences in dysrhythmia recognition sensitivity and specificity and 2) time to delivery of a defibrillation shock. While there appears to be evidence suggesting no significant differences between the three units in terms of dysrhythmia recognition, there do not appear to be any controlled 'time-to-defibrillation' studies. The purpose of this study was to determine if, under controlled conditions, any performance differences existed between these three units in time to delivery of a defibrillation shock. The results of this study suggest that there are no pragmatic differences between the three defibrillation units. In the absence of time-to-defibrillation differences, EMS systems managers can place more emphasis on other features so as to better address the needs, concerns, and resources of their system.