Distilled water or purified water is usually added to the oxygen wetting bottle because distilled water and purified water have less impurities through treatment and can ensure cleanliness. Oxygen wetting bottles usually add 1/3-1/2 of water. In case of acute pulmonary edema, 20%-30% alcohol should be added to the oxygen wetting bottle, which can reduce the surface tension of the foam in the alveoli, make the foam burst, improve the gas exchange in the lungs, and thus reduce the symptoms of hypoxia. Medical oxygen usually has no water, oxygen wetting bottle can make oxygen wet when the patient inhales oxygen, thus preventing the respiratory tract from drying out due to oxygen inhalation, so the purity of water in the bottle must be ensured.