The statement "The baseline pressure is elevated but is periodically released to a lower level for a very brief period, and the patient is allowed to breathe spontaneously at each level" describes which of the following ventilator modes?

a. Bilevel positive airway pressure
b. Pressure-controlled inverse-ratio ventila-tion
c. Airway pressure-release ventilation
d. Mandatory minute ventilation

ANS: C
Airway pressure-release ventilation provides two levels of continuous positive airway pressure and allows for spontaneous breathing at both levels. The ventilator is time triggered, pressure lim-ited, and time cycled. The low time is usually approximately 0.2 to 1 second.