Researchers at Karolinska Institutet have evaluated the possibility of alerting drones equipped with automated external defibrillators (AED) to patients with suspected cardiac arrest. In more than half of the cases, the drones were ahead of the ambulance by an average of three minutes. In cases where the patient was in cardiac arrest, the drone-delivered defibrillator was used in a majority of cases. The results have been published in the journal The Lancet Digital Health.