The consequences of carbon monoxide poisoning include acute poisoning (characterized by varying degrees of hypoxia) and delayed encephalopathy. 1. Acute poisoning: the severity of the disease is closely related to the concentration of inhaled carbon monoxide and the duration of exposure. (1) Mild poisoning: blood COHb concentration is 10% to 20%. Patients have different degrees of headache, dizziness, nausea, vomiting, palpitation and weakness of limbs. Angina pectoris may occur in patients with pre-existing coronary heart disease. The symptoms will disappear soon after getting out of the poisoned environment and inhaling fresh air or oxygen therapy. (2) Moderate poisoning: Blood COHb concentration is 30%-40%. The patient has chest tightness, shortness of breath, dyspnea, hallucinations, blurred vision, reduced judgment, dyskinesia, drowsiness, blurred consciousness or shallow coma. The mucous membrane of the mouth and lips may be cherry red. After oxygen therapy, the patient can return to normal without obvious complications. (3) Severe poisoning: Blood COHb concentration reaches 40%～60%. Coma, respiratory depression, pulmonary edema, cardiac arrhythmia or heart failure occur rapidly. The patient may be in the state of decorticate syndrome. Some patients are combined with aspiration pneumonia. Redness, swelling and blistering of the skin at the site of pressure. Funduscopic examination may reveal optic disc edema. 2. Delayed encephalopathy: After the recovery of acute carbon monoxide poisoning, after 2-60 days of “false healing period”, patients with acute carbon monoxide poisoning can have delayed encephalopathy manifestations, such as mental consciousness disorder, extrapyramidal neurological disorder, pyramidal neurological damage, cerebral nerve and peripheral nerve damage, etc. The same needs to be noticed. It is also important to pay attention to this. In daily life, we should pay attention to the use of gas heating cooking, coal stove heating to ensure ventilation. If carbon monoxide poisoning is found, it should be sent to the hospital for treatment in a timely manner, and should not be treated on its own, delaying the time for treatment.