Cardiopulmonary resuscitation chest compressions need to be controlled at 100~120 times per minute, and attention should be paid to the assessment of vital signs, airway opening, depth of compression and other items. 1. Indications for cardiopulmonary resuscitation chest compressions: mainly for drowning and other causes of cardiac arrest, need to be carried out only after the vital signs are clear cardiopulmonary arrest. 2. Frequency of chest compressions for cardiopulmonary resuscitation: for both adults and children, the recommended frequency of compressions is 100-120 per minute. 3. Depth of chest compressions for CPR: the depth of chest compressions for adults is at least 5cm; the depth of chest compressions for children and infants should reach 1/3 of the anterior-posterior diameter of the chest; you need to wait for the thorax to rebound after each compression before continuing the compressions. 4. The relationship between chest compressions and artificial respiration in cardiopulmonary resuscitation: the ratio of compressions to ventilation is 30 compressions with 2 artificial respirations as appropriate. And need to pay attention to open the airway before compression. Cardiopulmonary resuscitation is recommended to be prioritized by professionals, and immediately call 120 emergency services at the same time of cardiopulmonary resuscitation.