Automated external defibrillator and operator performance in out-of-hospital cardiac arrest

Aim: An increasing number of failing automated external defibrillators (AEDs) is reported: AEDs not giving a shock or other malfunction. We assessed to what extent AEDs are 'failing' and whether this had a device-related or operator-related cause. Methods: We studied analysis periods from AEDs used between January 2012 and December 2014. For each analysis period we assessed the correctness of the (no)-shock advice (sensitivity/specificity) and reasons for an incorrect (no)-shock advice. If no shock was delivered after a shock advice, we assessed the reason for no-shock delivery. Results: We analyzed 1114 AED recordings with 3310 analysis periods (1091 shock advices; 2219 no-shock advices). Sensitivity for coarse ventricular fibrillation was 99% and specificity for non-shockable rhythm detection 98%. The AED gave an incorrect shock advice in 4% (44/1091) of all shock advices, due to device-related (n = 15) and operator-related errors (n = 28) (one unknown). Of these 44 shock advices, only 2 shocks caused a rhythm change. One percent (26/2219) of all no-shock advices was incorrect due to device-related (n = 20) and operator-related errors (n = 6). In 5% (59/1091) of all shock advices, no shock was delivered: operator failed to deliver shock (n = 33), AED was removed (n = 17), operator pushed 'off' button (n = 8) and other (n = 1). Of the 1073 analysis periods with a shockable rhythm, 67 (6%) did not receive an AED shock. Conclusion: Errors associated with AED use are rare (4%) and when occurring are in 72% caused by the operator or circumstances of use. Fully automatic AEDs may prevent the majority of these errors. (C) 2017 The Author(s). Published by Elsevier Ireland Ltd.