Lactate refers to lactic acid, a product of anaerobic fermentation, which reflects the oxygen supply and metabolism of tissues and organs. Normal human plasma lactate concentration of 0.44 ~ 1.78mmol / L, when the lactate concentration is greater than 2mmol / L, it is called hyperlactatemia, which can be seen in physiological elevation, such as strenuous exercise, etc., but also can be seen in the pathological elevation, such as shock, infection, diabetes mellitus caused. 1. Physiological elevation: such as strenuous exercise, the human body to cope with the needs of exercise, oxygen consumption increases, anaerobic fermentation increases, lactate concentration rises. When exercise is stopped for a period of time, the lactate level can return to normal. 2. Pathological elevation: elevated lactate concentration due to various diseases. (1) Increase in lactic acid production: such as shock, infection, diabetes, CO poisoning, etc., due to the increase in tissue oxygen consumption or decrease in oxygen-carrying capacity, resulting in tissue and organ hypoxia, and then increase in anaerobic fermentation, the concentration of lactic acid rises. (2) Decreased utilization or excretion of lactic acid: such as severe liver disease, after extensive resection of small intestine, after short circuit surgery of small intestine, etc., due to the decrease of lactic acid utilization or excretion, which leads to the increase of blood lactic acid concentration. When hyperlactatemia is found, it is necessary to identify whether it is a physiological or pathological elevation, and it is recommended to consult the hospital and follow the doctor’s instructions for treatment.