Respiratory failure can be categorized into type I respiratory failure and type II respiratory failure according to the results of arterial blood gas analysis, acute and chronic according to the course of the disease, and central and peripheral according to the site of onset. 1. According to the results of arterial blood gas analysis, according to whether or not it is accompanied by carbon dioxide retention, it can be categorized into type I respiratory failure and type II respiratory failure. Type I respiratory failure is characterized by the presence of hypoxia without carbon dioxide retention. Blood gases are characterized by a partial pressure of oxygen (PaO2) less than 60 mm Hg and a reduced or normal partial pressure of carbon dioxide (PaCO2). Type 2 respiratory failure with carbon dioxide retention has both hypoxemia and hypercapnia. Blood gases are characterized by a partial pressure of oxygen (PaO2) of less than 60 mm Hg, accompanied by a partial pressure of carbon dioxide (PaCO2) of more than 50 mm Hg. However, it should be noted that the partial pressure of oxygen may still be in the normal range when type II respiratory failure occurs while the patient is on oxygen. 2. According to the course of the disease, it can be divided into acute respiratory failure and chronic respiratory failure. Acute respiratory failure is a respiratory failure that occurs within a few hours or days; chronic respiratory failure lasts for more than a few weeks, or even longer, and is often seen in chronic respiratory diseases. 3. According to the onset of the site can be divided into central respiratory failure and peripheral respiratory failure. Central respiratory failure refers to respiratory failure caused by direct or indirect damage to the respiratory centers, such as the medulla oblongata, cerebellum and thalamus. Peripheral respiratory failure is the result of severe lesions of the respiratory organs or paralysis of the respiratory muscles, resulting in impaired ventilation and hyperventilation. If you feel unwell, you should go to the hospital as soon as possible, and the doctor will formulate an individualized treatment plan according to your specific condition, so as not to delay your condition.