Patients in shock will have three phases of microcirculatory changes, also known as mild, moderate, and severe stages of shock. In the initial phase of shock, also known as the ischemic phase of microcirculation, there will be typical changes in clinical signs and typical symptoms. Usually, at this time, tissue perfusion is drastically reduced and self-reaction will occur, and the patient will have neurological excitation, followed by a gradual decrease in excitability and pallor. In the second stage, also called the stasis phase of microcirculation, when microcirculation cannot be corrected in time, cellular ischemia and hypoxia will persist, and patients will also have varying degrees of pallor, mental depression, wet and cold extremities, and gradual change of consciousness from excitement to indifferent state. The third stage is called diffuse intravascular coagulation stage, also known as the late stage of shock, at this time, if the shock is not corrected in time, there will be life-threatening conditions, patients will have a series of symptoms such as oliguria or even anuria, rapid drop in blood pressure, blood pressure measurement is unclear, and gradual loss of consciousness.