What defines Assist-control ventilation (AC) mode in ventilators?

Assist-control ventilation (AC) mode is characterized by the capability for patients to initiate breaths while ensuring that the ventilator can deliver a full tidal volume for each breath, regardless of whether it is initiated by the patient or the machine. This mode allows for better synchronization with patient efforts and provides support by ensuring adequate ventilation.

When a patient initiates a breath, the ventilator responds by supplying a complete, predetermined tidal volume. This feature is particularly beneficial for patients who may have variable respiratory drive or are unable to maintain adequate ventilation on their own, as the system guarantees that they will receive sufficient ventilation support.

This mode enhances patient comfort and can help prevent respiratory fatigue, making it suitable for patients who still retain some respiratory function but require assistance to maintain adequate ventilation. Such aspects differentiate this mode substantially from other ventilation strategies that may limit tidal volume or rely solely on mechanical control without patient input.