The most common way to open the airway in adult CPR is to tilt the head and lift the chin, that is, the rescuer puts the little thumb of one hand on the patient’s forehead and presses down hard to make his head tilt back, and the index and middle fingers of the other hand are placed close to the bottom of the chin bone and lift the chin bone upward to help the head tilt back further, so as to open the airway. If necessary, the lower lip can be gently pulled with the thumb, so that the mouth is slightly open, with the thumb and forefinger of the hand pressed on the forehead pinched the patient’s nostrils, and then the rescuer takes a deep breath and opens the mouth close to the patient’s mouth, paying attention to the patient’s mouth to be completely wrapped, and forcefully blowing to the patient’s mouth, blowing to be fast and deep, until the patient’s chest is lifted up, and there is a flow of air from the mouth and nose side of the exhaust, a blowing is completed! Immediately after the blowing is completed, the patient’s mouth should be detached from the patient, gently lift the head and eyes to look at the patient’s chest to see if there is a rise and fall of the thorax, so that the next artificial respiration can be done, and at the same time, the hand that pinches the nose should be relaxed so that the patient’s chest can be further relaxed, and there is a flow of air discharged from the nose and mouth, and the volume of air for each blowing is 800-1200 mL.