There is no clear limit to the number of days the ventilator can be used, it is based on the patient’s condition that determines whether to discontinue the ventilator or not, and some patients even need to use the ventilator for life. In clinical treatment, ventilator can be divided into non-invasive ventilator and invasive ventilator, the use of the two types of ventilator has certain differences, according to the severity of the patient’s condition and the cause of the disease to selective use. The application time of the ventilator depends on the development of the patient’s condition and the characteristics of the disease. For example, for patients with severe sleep apnea and hypoventilation syndrome, it is easy for them to have long-term and repeated interruptions of respiration during sleep, which triggers long-term chronic hypoxia in the organism. These patients often require lifelong non-invasive ventilator treatment during sleep. For severe respiratory failure caused by a variety of acute diseases, for example, for patients with an acute severe asthma attack requiring ventilator support, if the bronchospasm can be quickly and effectively relieved and controlled, the patient can be quickly removed from the ventilator within one day. For example, in acute respiratory distress syndrome caused by severe viral pneumonia, if the patient’s infectious disease is difficult to be effectively controlled, or even combined with infectious shock, multiple organ failure, etc., the patient’s respiratory failure will be difficult to be corrected, and the patient may face a prolonged period of time on the ventilator, the specific time is related to the patient’s condition of the treatment effect.