Overview Carbon monoxide (i.e., gas) poisoning is mostly caused by coal stoves without chimneys or chimneys that are closed and inaccessible, or by high winds blowing into the chimney, causing the gas to flow back into the room, or by the absence of ventilation equipment in the living room. Smelting workshop is not well ventilated, and engine exhaust and gunpowder explosion contain a lot of carbon monoxide. The mechanism of poisoning is that the affinity between carbon monoxide and hemoglobin is 200-300 times higher than the affinity between oxygen and hemoglobin, so carbon monoxide is very easy to combine with hemoglobin to form carboxyhemoglobin, which loses its oxygen-carrying capacity and causes tissue asphyxiation. Clinical manifestations At first, there are dizziness, headache, tinnitus, dizziness, weakness of limbs and general discomfort; if the symptoms gradually increase, there are nausea, vomiting, chest urgency, followed by drowsiness, coma, shortness of breath, drop in blood pressure, and even death. The severity of symptoms is related to the amount of carboxyhemoglobin. When the blood contains 10%-20% carboxyhemoglobin, headache and nausea occur; when it reaches 30%-50%, weakness, vomiting, dizziness, confusion, tremors, and even deficiency; when it reaches 50-60%, coma and convulsions occur; when it reaches 70%-80%, the respiratory center is paralyzed and the heart stops. Because of the red color of carboxyhemoglobin, the patient has no cyanosis, and the skin and lips are cherry red. Diagnosis The diagnosis can be confirmed based on the medical history and symptoms. Carbon monoxide examination method: ① blood is cherry red; ② take a drop of blood and add it to a glass of water to show a slight red color (normal people are yellow); ③ take several drops of blood and add 10ml of water, add several drops of 10% sodium hydroxide to show a pink color (normal people’s blood is green). Treatment measures Relocate the sick child to a place with clear air, but must keep warm, avoid being cold, not naked. Mild cases can recover slowly by leaving toxic places. Oxygen supply is very important because the higher the concentration of inhaled oxygen, the more carbon monoxide is separated from the blood and the faster it is expelled. Studies have shown that it takes 200 minutes to halve carbon monoxide in the blood in the room and 40 minutes to absorb pure oxygen. Therefore, the application of hyperbaric oxygen chamber is the most effective method to treat carbon monoxide poisoning. Put the patient into the hyperbaric oxygen chamber with 2~2.5 atmospheres pressure, after 30~60 minutes, the carboxyhemoglobin in the blood can be reduced to 0, and no heart damage can occur. After 36 hours of poisoning and then use the hyperbaric oxygen chamber treatment, it is not very effective. Early entry into the hyperbaric chamber can reduce the neurological and psychiatric sequelae and reduce the death rate. Hyperbaric oxygen can also cause vasoconstriction, reduce tissue edema, and is beneficial to the prevention and treatment of pulmonary edema. If available, oxygen and carbon dioxide mixture (oxygen about 93%, carbon dioxide about 7%), carbon dioxide is an important factor to stimulate respiration, so regardless of the early and late stages are appropriate to supply some carbon dioxide in the oxygen infusion. Generally, there is no carbon dioxide supply and hyperbaric chamber, and in cases of respiratory distress, mouth-to-mouth artificial respiration can be performed intermittently when artificial respiration and oxygen are applied. In addition, cardiac stimulants, respiratory stimulants, fluids, blood transfusion, treatment of shock, cerebral edema and anti-infection are very important. Artificial hibernation and cooling therapy also have some effect. After 2-4 hours of acute poisoning, the patient can show cerebral edema, which reaches a peak in 24-48 hours and can last for many days. Therefore, dehydrating agents such as mannitol and hypertonic glucose should be applied in a timely manner by alternating intravenous drip, and diuretics and dexamethasone should be used at the same time. Prevention It should be widely publicized that there should be safety settings (such as chimneys, small ventilation windows, wind hoppers, etc.) when using coal fires indoors, explaining the possible symptoms of gas poisoning and common sense of first aid, especially emphasizing the danger and seriousness of gas to small infants. The chimney of the coal stove should be reasonably installed, and coal stoves without chimneys should be placed outdoors at night. Prognosis Mild cases recover completely within a few days, while severe cases may develop neurological sequelae. Treatment is prone to complications of pneumonia if exposed to excessive cold.