The steps of primary CPR mainly include chest compressions, open airway, and artificial respiration. First of all, external chest compressions, external chest compressions are generally performed with the palms of both hands alternately overlapping, with the heel of the palm of the hand on the lower part of the sternum, elbow joint straightened, vertical downward pressure, the general depth of compressions is 5-6 cm, the frequency of compressions is more than 100 times per minute. After 30 chest compressions, the airway must be opened. Before opening the airway, the foreign body in the mouth must be removed, and if there is vomit, it must be excluded, and if there are dentures, they must be removed. After removing the oral foreign body, then give open airway, and then two artificial respiration, artificial respiration must be seen when the chest heave to be effective. After two artificial respirations, turn back to 30 chest compressions, the ratio of chest compressions to artificial respiration is 30:2. After five sets of chest compressions and artificial respiration, you can take a short pause to observe whether the patient’s breathing and heartbeat have recovered, and if not, continue the above operation.