Introduction of the ventilator
In modern clinical medicine, the ventilator as an effective means of artificially replacing the function of autonomous ventilation, has been widely used in various causes of respiratory failure, anesthesia during major surgery respiratory management, respiratory support therapy and emergency resuscitation, in the field of modern medicine occupies a very important position. The ventilator is a medical device that can prevent and treat respiratory failure, reduce complications, and save and prolong the patient's life.
Categorization of ventilators
I. According to the use or application of the type of classification
(a) controlled mechanical ventilation (CMV)
1. Definition: the patient in the case of voluntary respiration is weakened or disappeared, completely by the mechanical ventilation machine to produce, control and regulate the patient's breathing.
2. Application: the disappearance or weakening of voluntary respiration caused by disease; voluntary respiration is irregular or too fast, mechanical ventilation can not be coordinated with the patient, the voluntary respiration will be suppressed or weakened by artificial methods.
(ii). Assisted mechanical ventilation (AMV)
1. Definition: Ventilator-assisted or augmented voluntary respiration in the presence of patient's breath. The various kinds of mechanical ventilation are triggered primarily by the patient's inspiratory negative pressure or inspiratory airflow.
2. Application: although the voluntary respiration exists and is more regular, but the voluntary respiration is weakened and the ventilation is insufficient.
II. Classification of mechanical ventilation according to the route of use
(I) Intrachestal or airway pressurization type
(II) Extrachestal type
3. Classification according to the way of switching between inspiratory and expiratory phases
(I) Fixed-pressure type: after the pressure in the airway reaches the expected value, the ventilator opens the expiratory valve and the thorax and lungs are passively atrophied or the expiration is generated by the negative pressure, and when the pressure in the airway keeps decreasing, the ventilator generates the airflow by the positive pressure once again and causes the inhalation.
(ii) Constant volume type: the predicted tidal volume is delivered to the lungs by positive pressure, and when the predicted tidal volume is reached, the air supply is stopped and the expiratory state is entered.
(3) Timed: Supply air according to the pre-designed time of inspiration and expiration.
(4) Hybrid type (multi-function type).
IV. Ventilation according to the ventilation frequency
(1) High-frequency ventilation: ventilation frequency >60 times/minute.
1. Advantages: low airway pressure, low intrathoracic pressure, little interference with circulation, no need for airway closure.
2. Disadvantages: unfavorable carbon dioxide elimination.
3. Classification: high-frequency positive pressure ventilation, high-frequency jet ventilation, high-frequency oscillatory ventilation.
(ii) normal frequency ventilation: ventilation frequency <60 times/minute.
V. Classified according to whether there is a synchronization device or performance
(a) synchronization type ventilator: the patient's spontaneous respiration of inhalation can be triggered at the beginning of the ventilator, so that it is supplied to the patient's airway, and to produce the inspiratory action.
(2) Non-synchronized ventilator: the patient's breathing or negative inspiratory pressure can not trigger the ventilator to supply air, generally only used for patients with controlled mechanical ventilation.
VI. Classification according to the applicable objects
(a) Infant ventilator
(b) Infant ventilator
(c) Adult ventilator
7. Classification according to the working principle
(I) Simple ventilator
(II) Membrane lung