Methods of cardiopulmonary resuscitation:

First, judgment. Pat the patient on the shoulder and call with both ears. If the patient is awake, he should continue to observe. If there is no response, he will be in a coma and proceed to the next process.

Second, open the airway. Put one hand on the patient's forehead, then push his head back with the palm of his hand, put the fingers of the other hand under the jaw near the chin, and lift the jaw to lift the chin.

Third, check foreign bodies. When opening the airway, check whether there is any foreign body or vomit in the patient's mouth. If yes, dig out the foreign body or vomit in the patient's mouth with your fingers. If you have false teeth, you should take them out.

Fourth, chest compressions. Make sure that the patient lies on his back on a flat ground, or put a chest pressure plate on his shoulder. First aiders can use kneeling posture or footstool to place the palm root of one hand in the center of the patient's chest and the lower part of the sternum, and the palm root of the other hand in the first hand. Don't touch the chest wall with your fingers. When pressing, the elbow should be straight, and press hard vertically downward.

The frequency of adult pressing is at least 100 times/minute, and the depth of pressing is at least 125px. After each press, the chest should be fully recovered, and the press time and relaxation time account for about 50% respectively. When relaxing, the palm root should not leave the chest wall to avoid the displacement of the pressing point.