S/T mode (autonomous/time-controlled mode)
In this mode, the ventilator delivers a higher pressure (IPAP) during the inspiratory phase and a lower pressure (EPAP) during the expiratory phase. This mode is mainly based on the patient's spontaneous breathing. If the patient cannot trigger breathing within the interval set by the frequency, the ventilator will trigger forced breathing according to the set inspiration time.
This is the most widely used model in clinical practice, and is suitable for patients with relatively stable spontaneous breathing, but at the same time, there is a potential for respiratory arrest or respiratory weakness.
CPAP mode (continuous positive airway pressure mode)
The characteristic of this mode is that the patient needs to have strong spontaneous breathing, and all the breathing work is completed by the patient. The ventilator has no trigger and no switching link during the working process, but continuously provides the same pressure in the inspiratory phase and the expiratory phase (I. e. CPAP = IPAP = EPAP) to help the patient reduce airway resistance and maintain the upper airway open state.
This model has the advantages that patients can breathe freely and have good comfort, but at the same time it has the disadvantages of inaccurate tidal volume and basically no additional ventilation assistance. This model is suitable for type I respiratory failure, acute and chronic heart failure (especially for cardiogenic pulmonary edema with heavy relative volume load), and obstructive sleep apnea syndrome.
PCV mode (pressure controlled ventilation mode)
The characteristic of this mode is that the ventilator performs forced ventilation according to the set parameters, which can be triggered by the patient or the machine. Similar to the/C mode of an invasive ventilator. This mode has the same parameters as the S/T mode setting, but is generally only used for emergency situations.
AVAPS mode (average volume guaranteed pressure support mode)
This mode is characterized by automatic adjustment of the pressure support level to achieve the target volumetric tidal volume. However, it should be noted that although this mode has a tidal volume setting, it is not equal to "volume control". It is essentially a pressure target ventilation, that is, the tidal volume level of the patient is automatically monitored, and if it is lower or higher than the preset value, the support pressure level will be automatically adjusted to ensure the preset target tidal volume. This model has certain advantages for patients with nocturnal hypoventilation and progressive lung disease.
Mode, patient, breathing, pressure, ventilation, ventilator, tidal volume, setting, autonomic
