The accuracy of decision-making of a semi-automatic defibrillator during cardiac arrest

A semi-automatic defibrillator was assessed at 57 cardiac arrests in 55 patients. Initial rhythm was ventricular fibrillation at 40 arrests and was correctly identified in 37 (sensitivity 92.5%). In the other 17 arrests initial rhythms were not ventricular fibrillation and 16 were correctly identified (specificity 94 %). Continuous ECG recordings of the arrests were analysed in 8 to 12 second segments; when those segments with cardio-pulmonary resuscitation artefact were excluded, a sensitivity of 91% and specificity of 96% were recorded.