1. Basic Life Support (BLS): also known as initial resuscitation or on-site first aid. Its main purpose is to supply oxygen to the heart, brain and vital organs of the whole body, prolonging the body's tolerance of clinical death. The main means of resuscitation at this stage is unarmed cardiopulmonary resuscitation.
2. Further life support period (ALS period): The main purpose is to apply assistive devices and special techniques on the basis of BLS, to establish and maintain effective ventilation and blood circulation, to recognize and treat cardiac arrhythmia, to establish effective venous access, to improve and maintain cardiorespiratory function, and to treat the primary disease. It is the 2nd stage of management 5 to 10 minutes after cardiac arrest and is usually performed in a medical unit. It includes a series of measures to maintain and monitor cardiopulmonary function, including the establishment of intravenous access, drug therapy, electrical defibrillation, endotracheal intubation, and mechanical ventilation.
3. Extended life support period (PLS period): the focus is on brain protection, brain resuscitation and prevention and treatment of post-resuscitation diseases. That is, in addition to active brain resuscitation, should closely monitor the heart, lungs, liver, kidneys, coagulation and digestive organs function, once abnormalities are found immediately take targeted treatment.