AED is an automated external defibrillator, the use of which includes turning on the power, placing the electrode pads according to the prompts, automatic monitoring of the heart rhythm, prompting defibrillation if defibrillation is needed, and pressing the defibrillation button to defibrillate, and other operational steps. 1. Turn on the power: When the AED is obtained, place the AED next to the patient, open the cover of the AED, insert the electrode plate plug into the jack of the AED mainframe, and turn on the power; note that while preparing the AED, CPR should be performed continuously. 2. Place the electrode pads: Undo the patient’s clothes and ensure that the patient’s chest is dry and uncovered, affix the electrode pads so that the electrode pads can fully contact the skin, and affix the two electrode pads to the corresponding positions according to the prompts and labels. 3. Defibrillation: operate the AED according to the voice prompts, wait for the AED to analyze the heart rhythm, avoid contacting the patient when analyzing the heart rhythm, which may lead to inaccurate analysis; after the analysis is completed, the AED will issue a recommendation on whether to defibrillate or not, and after reminding and confirming that all the people are not in contact with the patient, press the “discharging” button to defibrillate. After defibrillation is completed, if the patient has not regained breathing and heartbeat, CPR should be continued, and the AED should be used again to detect the heart rhythm and respond according to the prompts until medical personnel arrive. AED has been gradually installed in public places as a means of emergency rescue treatment. When cardiac arrest or malignant arrhythmia occurs, it can be used in accordance with the above methods, and at the same time, call the 120 emergency telephone.