Wide variation in cardiopulmonary resuscitation interruption intervals among commercially available automated external defibrillators may affect survival despite high defibrillation efficacy

OBJECTIVE:Recent studies have associated interruptions of cardiopulmonary resuscitation imposed by automated external defibrillators (AEDs) with poor resuscitation outcome. In particular, the “hands-off” interval between precordial compressions and subsequent defibrillation shock has been implicated. We sought to determine the range of variation among current-generation AEDs with respect to this characteristic. MEASUREMENTS:Seven AEDs from six manufacturers were characterized via stopwatch and arrhythmia simulator with respect to the imposed hands-off interval. All AEDs were equipped with new batteries, and measurements were repeated five times for each AED. MAIN RESULTS:A wide variation in the hands-off interval between precordial compressions and shock delivery was observed, ranging from 5.2 to 28.4 secs, with only one AED achieving an interruption of