Sudden deafness is an unexplained sensorineural deafness that occurs suddenly in a normal person within a short period of time and is a common clinical condition. Why does sudden deafness require hyperbaric oxygen therapy? It has to do with the mechanism of action of hyperbaric oxygen. The mechanism of action of hyperbaric oxygen therapy for sudden deafness is as follows: 1. It can rapidly increase the partial pressure of oxygen in human body, increase the blood oxygen content and improve the distance of oxygen diffusion in capillaries. Nerve repair. 2. It can constrict the blood vessels of the whole body, and constrict the intracranial internal carotid artery system, but has a dilating effect on the vertebrobasilar artery blood vessels. The labyrinth artery is a branch of the basilar artery, so the blood supply to the inner ear will not be reduced but increased during hyperbaric oxygen therapy. 3.Improve the permeability of inner ear capillary endothelium, reduce the exudation, and improve the edema of inner ear caused by hypoxia. 4.It can reduce the number of red blood cells and blood viscosity, and improve the blood circulation in the inner ear. 5.It can enhance the ability of phagocytes to engulf pathogenic microorganisms and remove necrotic cells. Several domestic literature reported that the efficiency of hyperbaric oxygen combined with drug treatment is significantly higher than that of drug treatment alone. Hyperbaric oxygen therapy is recommended as a treatment method in both Chinese and American guidelines for the treatment of sudden deafness. Therefore, patients with sudden deafness should start hyperbaric oxygen therapy as early as possible.