The microcirculatory phase of shock is divided into three stages, usually the microcirculatory ischemic phase, the microcirculatory stasis phase and the diffuse intravascular coagulation phase. In the first stage, the patient develops microcirculatory ischemic phase, which is also the initial stage of shock, and the tissue perfusion is drastically reduced, causing the body to react on its own, usually releasing a large amount of renin-angiotensin in the body, activating the aldosterone system, and the sympathetic nerves and adrenal medulla will also be strongly excited, at which time the microcirculation is in the ischemic phase, but there is no obvious drop in blood pressure. In the second phase of microcirculatory stasis, patients experience a large accumulation of lactate metabolites and other acidic metabolites in the microcirculation. The third phase is the diffuse intravascular coagulation phase, when the patient will experience stagnant blood in the microcirculation can do and the blood flow will be even slower.