Cerebral hypoxia can mainly cause various functional disorders, and can be divided into acute hypoxia and chronic hypoxia according to the duration of hypoxia. Acute hypoxia generally results in dizziness and headache, tinnitus, weakness of limbs, nausea and vomiting, shallow and rapid breathing, accelerated heart rate and other discomforts. Most of them are triggered by the decrease of oxygen concentration in the surrounding environment, such as acute carbon monoxide poisoning and being in a closed room. If the state of hypoxia does not improve, the symptoms will gradually worsen and can lead to loss of consciousness and death by asphyxiation. Chronic hypoxia is mostly secondary to chronic diseases such as pulmonary encephalopathy. The onset of the disease may be preceded by prodromal symptoms: mental depression, insomnia, excessive sweating; personality changes, sudden talkativeness or silence, irritability or laughing easily; impaired calculation ability. As the disease worsens, mild hypoxic symptoms may appear: mental abnormalities such as trance, indifference, drowsiness and excitement, but no positive neurological signs. Moderate hypoxic symptoms such as shallow coma, delirium, muscle twitching, general edema, and unresponsiveness to stimuli may appear as the lesion continues to worsen. If severe hypoxia is entered, symptoms such as conjunctival congestion and edema, generalized sweating, loss of response to various stimuli, dilated or narrow pupils, epileptiform convulsions, coma, etc. may appear, and there may be coffee-colored vomit due to combined upper gastrointestinal bleeding. If treatment is not carried out in time, it can lead to death soon. Cerebral hypoxia can cause different degrees of damage to brain cells and needs to be treated as early as possible once it occurs.