Refers to modes of ventilation where the volume of the tidal breath is set. E.g. we set the ventilator to deliver a breath of 500 ml. Setting the rate is normally mandatory for this method of controlling ventilation. E.g. we set the tidal volume (Vt) at 500 ml to be delivered at a rate of 14 bpm (breath per minute). The ventilator in this example is set to deliver a minute volume of 500 x 14 = 7 litres.
The airway pressure in this mode of ventilation will depend on the lung and chest wall compliance. Indeed the airway pressure might change from breath to breath depending on many factors.