Type I respiratory failure, also known as hypoxic respiratory failure, is characterized by a blood gas analysis with an oxygen partial pressure <60 mmHg and a reduced or normal carbon dioxide partial pressure, both hypoxia without carbon dioxide retention, or only with a reduced carbon dioxide partial pressure. The disease is mainly seen in diseases of pulmonary ventilation dysfunction, such as ventilation/blood flow disorders, impaired diffusion, diseases caused by pulmonary artery and venous shunts, including severe infectious lung diseases, interstitial lung diseases, interstitial fibrosis, acute pulmonary embolism and other related diseases.