Cardiopulmonary resuscitation ABC Step A: Open airway B: Mouth-to-mouth artificial respiration C: Artificial circulation A: Open airway, pat patient and ask loudly. Pinch your nails for about five seconds. If there is no response, it means losing consciousness. At this point, the patient should lie flat, unbutton his neck, and pay attention to removing foreign bodies from his mouth, so that the patient can raise his head and lift his chin, and his ears are close to his nose and mouth. If there is no airflow or chest fluctuation, it means he is not breathing. B. Mouth-to-mouth artificial respiration On the premise of keeping the patient's head up and chin up, the rescuer holds the nostril (or lips) with one hand, then takes a deep breath, blows into the patient's mouth (or nose) quickly and forcefully, then relaxes the nostril (or lips), and repeats this action every 5 seconds until spontaneous breathing is resumed. The interval of each blowing is 1.5 seconds. At this point, the rescuer should take a deep breath and continue mouth-to-mouth breathing until the professional rescuer arrives. C artificial circulation to check whether the heart is beating, the simplest and most reliable is the carotid artery. The rescuer puts 2-3 fingers between the patient's trachea and neck muscles and gently presses them for at least 10 second. If the patient's heart stops, the rescuer should clench his fist, punch his eyes upward and punch the patient in the middle and lower sternum quickly and forcefully. This may make the patient's heart beat again. If you don't succeed at one time, you can deduct it again according to the above requirements. If the heart can't beat any more, you should press the chest to let the blood flow in the heart and big blood vessels. So as to maintain that minimum blood requirement of major organs such as the heart and brain. Selection of chest compressions: First, specify the lower edge of the rib with the middle finger of the left hand and food, then put the palm of the right hand under the sternum 1/3, and then put the left hand above the sternum, with the thumb of the left hand adjacent to the finger of the right hand, so that the bottom of the palm of the left hand is on the xiphoid process. Put your right hand on your left hand and stagger or stretch your fingers. The amount of downward pressure follows the hand downward, and the finger should be lifted off the chest. Method of chest compression: First aiders should put their arms directly above the patient's sternum, straighten their elbows, press vertically with the weight of the upper body, and press the middleweight adult to a depth of 3-4 cm, then quickly relax, relieve the pressure and let the chest reset itself. Repeated rhythmic pressing, the relaxation time is roughly equal, and the frequency is 80- 100 times per minute. Single-person CPR: When only one rescuer gives CPR to the patient, artificial respiration should be given twice every 30 chest compressions. Two-person CPR: When two first responders give a patient CPR, first of all, they should be in a symmetrical position to facilitate mutual exchange. At this point, a person does chest compressions; The other person does artificial respiration. Two people can count 1, 2, 3 to match. Every 30 compressions of the heart, mouth-to-mouth or mouth-to-mouth artificial respiration is performed twice. )