Brain hypoxia refers to the lack of sufficient endogenous oxygen for brain cells, which is divided into two conditions: general hypoxia and severe hypoxia according to different manifestation symptoms: 1.General hypoxia: general hypoxia patients may have discomfort symptoms such as blurred eyes, dizziness, headache, weakness of limbs and tinnitus, etc., and the continuous development may lead to nausea, vomiting, fast and weak heartbeat, fast and weak breathing, etc.; 2.Severe hypoxia: severe hypoxia patients will Severe hypoxia may lead to coma and death due to respiratory distress, cardiac arrest and hypoxic asphyxia. Oxygen is a substance necessary for the brain to maintain its function and is the key to the metabolic activities of the human body, and the brain mainly relies on aerobic enzymatic decomposition of glucose for energy. Prolonged lack of oxygen in the brain can cause irreversible damage and, in severe cases, brain death. The tolerance of general brain tissue to hypoxia is usually poor. Brain cells will stop electrical activity when the brain is deprived of oxygen for 2 minutes, and irreversible damage will occur after the brain is deprived of oxygen for 5 minutes, which may trigger cognitive decline and impaired functional activities, such as weakness and numbness of limbs. Therefore, once the symptoms related to cerebral hypoxia appear, you should go to the hospital as soon as possible, and then treat different causative factors to improve the current situation under the guidance of the doctor. The principle of treatment is to repair damaged neurons and maintain the stability of the internal environment, and at the same time, drugs such as mannitol should be given to reduce cerebral edema and improve brain cell metabolism and cerebral blood flow.