Mild gas poisoning usually does not require hyperbaric oxygen treatment, but only headache, weakness, dizziness, and difficulty in breathing during labor. As long as the patient leaves the poisoned environment and inhales fresh air or oxygen, the symptoms will soon be relieved and hyperbaric oxygen treatment is not required. In case of moderate to severe gas poisoning, the patient may experience nausea, vomiting, blurred consciousness, deficiency, coma, convulsions, and cerebral edema, which require hyperbaric oxygen support treatment. Hyperbaric oxygen is a relatively advanced treatment. Hyperbaric oxygen has a vasoconstrictive effect and can reduce cerebral edema. Hyperbaric oxygen also has an antibacterial effect on both anaerobic and aerobic bacteria. In addition, it can also remove toxic substances from the body, such as large amounts of oxygen can accelerate the removal of harmful gases in the body, such as harmful gases nitric oxide, carbon monoxide, methylene chloride, nitrogen, etc.. It can also increase the oxygen content in the body and provide oxygen supply to the tissues. For ischemic and hypoxic diseases of the nerves, they can be treated with hyperbaric oxygen.