Ventilators are divided into non-invasive ventilators and invasive ventilators. Non-invasive ventilators do not require intubation and are connected by a mask, while invasive ventilators require intubation. 1. Non-invasive ventilator: Non-invasive ventilator is suitable for patients with respiratory failure and sleep apnea hypoventilation syndrome as well as myasthenia gravis. Non-invasive ventilator is to help patients to breathe on their own, it is not recommended for some patients who are not conscious. It is not recommended for patients who are vomiting or have a lot of sputum. 2. Invasive ventilator: It requires endotracheal intubation and connection to a ventilator, which can maintain the patient’s respiratory function and buy time to treat respiratory failure. Corrects hypoxemia and carbon dioxide retention by improving gas exchange in the lungs. Severe cases of hypoxemia, respiratory failure, and coma require aggressive tracheal intubation for mechanical ventilation, but at the same time invasive ventilator use can cause complications such as infections and pneumatic injuries. The choice of ventilator type and the adjustment of parameters need to be decided according to the needs of the condition, and the use of ventilators needs to be under the guidance of a doctor.