The difference between type I and type II respiratory failure is mainly in the different arterial blood gas performance. 1. Type I Respiratory Failure: is the partial pressure of carbon dioxide is reduced or normal, but the partial pressure of arterial blood oxygen is less than 60 mmHg. Patients with severe interstitial lung disease, infectious lung disease, acute pulmonary embolism and other lung ventilation dysfunction diseases are prone to type I respiratory failure. 2. Type 2 respiratory failure: In addition to an arterial partial pressure of oxygen less than 60 mm Hg, there is also an arterial partial pressure of carbon dioxide greater than 50 mm Hg. Type II respiratory failure occurs when the body’s alveolar ventilation is insufficient, so the probability of type II respiratory failure in patients with COPD is much higher than in patients with other lung diseases. The occurrence of respiratory failure is a dangerous thing, if you can not get effective treatment after the occurrence of respiratory failure, it is likely to lead to physiological disorders of the body, serious life-threatening. It is recommended to go to the hospital in time when there is a lung disease manifestation, to avoid delaying the treatment of the disease.