High-flow oxygen is a therapeutic modality that provides patients with a continuous supply of high-flow (4-6 L/min) inhaled gas through a high-flow nasal cannula. The gas provided by high-flow oxygenation can be regulated and relatively constant, with an oxygen flow rate of greater than 4 L/min or an oxygen concentration of greater than 40% in the inhaled gas, at a temperature of 31-37°C, and with appropriate humidity. This technique is suitable for patients with acute respiratory failure, acute respiratory distress syndrome, and type II respiratory failure. High-flow oxygen inhalation has a higher concentration of oxygen in the mask relative to ordinary oxygen inhalation and mask oxygen inhalation because it has a mutually independent gas discharge tube and inhalation tube. Compared to hyperbaric oxygen, although it does not have the same blood oxygen capacity as hyperbaric oxygen, high-flow oxygen inhalation does not need to enter the hyperbaric oxygen chamber, so it is safer and more convenient for treatment. If you need to perform high-flow oxygen, you need to be under the guidance of a professional.