The invisible killer around you

This is the 5248th article of Da Yi Xiao Hu

Every winter is a high-incidence season for carbon monoxide poisoning, which is mostly caused by burning charcoal for heating, using coal stoves or gas water heaters, etc., because the room is closed and the air is not ventilated. After carbon monoxide poisoning, mild symptoms include headache, dizziness, nausea, vomiting, general weakness, and rapid heartbeat. Many people will mistake it for a cold or enteritis and fail to leave the scene in time. As the poisoning deepens, people will become confused, their skin will flush, their hands and feet will become unresponsive, and they will lose the ability to save themselves.

Carbon monoxide poisoning is caused by inhalation of the product of incomplete combustion of carbon-containing substances through the respiratory tract. The poisoning mechanism is that the affinity of carbon monoxide for hemoglobin is 200 to 300 times higher than that of oxygen for hemoglobin, so carbon monoxide can easily combine with hemoglobin to form carboxyhemoglobin, which makes hemoglobin lose its oxygen-carrying capacity and function, causing tissue asphyxiation. It has toxic effects on tissue cells throughout the body, especially the cerebral cortex.

1. Mild poisoning

A. The patient only has symptoms such as headache, dizziness, palpitations, blurred vision, nausea, and vomiting.

B. If you can quickly leave the scene and breathe fresh air, the symptoms will disappear quickly.

C. Blood HbCO concentration is 10%~20%.

2. Moderate poisoning

A. In addition to the worsening symptoms of mild poisoning, there are also flushed face, cherry red lips, excessive sweating, rapid heart rate, restlessness, and gradually falling into a coma.

B. Blood HbCO concentration is 30%~40%.

3. Severe poisoning

A. The patient quickly falls into a coma, with a cherry red face, sweating all over the body, increased body temperature, faster breathing, a fast and weak pulse, decreased blood pressure, limp limbs or paroxysmal tonic convulsions, and constricted or dilated pupils.

B. Respiratory depression may occur, with serious central nervous system sequelae;

C. Blood HbCO concentration can be higher than 50%.

4. Manifestations of delayed encephalopathy after poisoning

A. Mental disorder. Hallucinations, auditory hallucinations, depression, irritability and other mental abnormalities occur.

B. Extrapyramidal nerve disorders. Parkinson's disease syndrome occurs.

C. Extrapyramidal nerve damage and focal dysfunction of the cerebral cortex.

How should we deal with carbon monoxide poisoning? First of all, we should cut off the source of carbon monoxide, open the window for ventilation immediately to allow air convection, quickly turn off the gas, gas stoves, water heater valves, pipeline gas facilities and equipment, and extinguish the charcoal fire. Then quickly remove the patient from the poisoning scene and transfer him to a place with fresh air and good ventilation. And unbutton the collar of the poisoned person, keep the airway open, and pay attention to keeping warm to prevent complications. The patient should keep quiet and rest to avoid increasing oxygen consumption, and let the patient breathe oxygen as soon as possible if conditions permit. While performing on-site first aid, you should immediately call 120 emergency number and send him to a hospital with a hyperbaric oxygen chamber for treatment as soon as possible. For critically ill patients with respiratory and cardiac arrest, artificial respiration and cardiac compression should be given immediately on the spot, and he should be quickly transferred to the hospital for emergency treatment. Even after effective treatment, severe carbon monoxide poisoning will leave serious sequelae, such as delayed encephalopathy. It causes great harm to the human body.

In cold seasons, if conditions permit, try to choose central heating. When using coal stoves, charcoal fires and other heating equipment indoors, ensure that the coal is fully burned and do not cover it. Open doors and windows frequently for ventilation to keep the indoor air fresh. When using coal stoves, charcoal fires and other heating equipment at home, it is best to install carbon monoxide detectors and regularly check and maintain them to ensure the normal operation of the detectors.

Shanghai Sixth People's Hospital Lingang Campus

Ma Yanping, emergency department nurse