Classification of Ventilator

Classification of Ventilator

       As equipment for treatment, first aid, and resuscitation, today's ventilators have more and more functions and their performance is becoming more and more perfect. Currently, there are more than 200 types of ventilators in clinical use in the world, which are usually divided into the following categories according to custom:

     1) Classification according to power source

     (1) Pneumatic air-controlled ventilator port

     It only uses oxygen as the gas source and does not require an external power supply. Since it uses all-pneumatic components to achieve the ventilation function, its functions are generally relatively simple. It is mostly used in first-aid situations and situations with strict requirements for electromagnetic interference.

     (2) Pneumatic electrically calibrated ventilator

     It usually requires external air and compressed air. The control part is more complicated. Use electronic or advanced computer technology. It is composed of high-precision flow and pressure sensors and durable control valves. It has multiple ventilation modes and monitoring of multiple respiratory parameters. Some also have curve waveforms and trend analysis of respiratory mechanics.

     (3) Electrically controlled ventilator

     Generally, only oxygen is used as the gas source, and no compressed air is required to ventilate the patient under normal pressure. Most of these ventilators have cylinders, piston pumps, etc. inside, but their inspiratory trigger sensitivity is low and their inspiratory response time is long. They often cannot be well synchronized with the patient, which limits their application.

     2) Classification according to the switching method from inhalation to exhalation

     (1) Pressure switching type: The pressure switching method is used to manage ventilation through airway pressure. Its advantage is that the pressure is controllable, which helps to judge the efficacy of the ventilator; its main disadvantage is that it cannot maintain stable moisture and requires high operating requirements for doctors.

     (2) Volume switching type: its basic working process is to ventilate the patient at predetermined tidal and peak flow values, and when the lungs are inflated and expanded. When the volume and flow rate reach a set value, the air supply is immediately stopped and the inhalation is switched to exhalation. Its advantage is that it can keep the ventilation volume stable and is easy to adjust, so it is suitable for long-term artificial ventilation for any disease; its disadvantage is that the pressure during ventilation is unstable, and it is easy to cause airfoot and hypotension.

     (3) Time switching type: The basic working process is a predetermined breathing cycle. Switch between inhalation and exhalation regularly according to the set tidal volume. It has the characteristics of constant pressure and constant volume. However, it has a certain impact on lung compliance and airway resistance. When compliance and airway resistance change, the inspiratory pressure, volume, and flow rate will all change. This type of ventilator is generally small and compact and is mostly used for first aid.

     (4) Combined switching type: it has a variety of suction phase conversion methods. Various conversion methods are set as needed. Under the intelligent control of the computer, the machine automatically adjusts relevant parameters to realize air supply. The advantage of this type of ventilator is that computer control can ensure high accuracy. It has powerful expansion functions, easy operation, strong versatility, complete breathing modes, and is suitable for treating various patients.

   3) Classification by application objects

      According to the classification of ventilator applications, it can be divided into adult ventilators, pediatric ventilators, and adult and pediatric ventilators.