I. Classification by type of use or application
(I) Controlled mechanical ventilation (CMV) 1. Definition: When the patient's spontaneous breathing is weakened or absent, the patient's breathing is completely generated, controlled and regulated by the mechanical ventilator. 2. Application: When spontaneous breathing disappears or weakens due to disease; when spontaneous breathing is irregular or too frequent, and mechanical ventilation cannot coordinate with the patient, the spontaneous breathing is artificially suppressed or weakened.
(II) Assisted mechanical ventilation (AMV) 1. Definition: When the patient's breathing exists, the ventilator assists or enhances the patient's spontaneous breathing. Various types of mechanical ventilation are mainly triggered by the patient's inspiratory negative pressure or inspiratory airflow. 2. Application: Although spontaneous breathing exists and is relatively regular, it is not suitable for patients with weakened spontaneous breathing and insufficient ventilation.
II. Classification by the use of mechanical ventilation
(I) Intrathoracic or airway pressurization type
(II) Extrathoracic type
III. Classification by switching mode of inhalation and exhalation phase
(I) Constant pressure type: After the pressure in the respiratory tract reaches the expected value, the ventilator opens the exhalation valve, the chest and lungs passively collapse or exhalation is generated by negative pressure. When the pressure in the airway continues to drop, the ventilator generates airflow through positive pressure again and causes inhalation.
(II) Constant volume type: The expected tidal volume is delivered to the lungs through positive pressure. After reaching the expected tidal volume, the air supply is stopped and the exhalation state is entered.
(III) Timing type: Air is supplied according to the pre-designed inhalation and exhalation time. (IV) Mixed type (multi-functional type).
IV. Air supply according to ventilation frequency
(I) High-frequency ventilation: ventilation frequency>60 times/min. 1. Advantages: low airway pressure, low intrathoracic pressure, little interference with circulation, no need to close the airway. 2. Disadvantages: not conducive to the removal of carbon dioxide. 3. Classification: high-frequency positive pressure ventilation, high-frequency jet ventilation, high-frequency oscillation ventilation.
(ii) Normal frequency ventilation: ventilation frequency <60 times/min.
V. Classification by whether there is a synchronization device or performance
(i) Synchronous ventilator: The patient's spontaneous breathing can trigger the ventilator at the beginning of inspiration, so that it can supply air to the patient's respiratory tract and produce an inhalation action.
(ii) Asynchronous ventilator: The patient's breathing or inhalation negative pressure cannot trigger the ventilator to supply air, and it is generally only used for patients with controlled mechanical ventilation.
VI. Classification by applicable objects
(i) Infant ventilator
(ii) Toddler ventilator
(iii) Adult ventilator
VII. Classification by working principle
(i) Simple ventilator
(ii) Membrane lung