Which type of ventilator mode allows for patient-initiated breaths in addition to controlled breaths?

The Assist-Control (AC) mode is designed to support patients who may initiate their own breaths while still allowing for controlled ventilation delivered by the machine. In this mode, if the patient initiates a breath, the ventilator recognizes this effort and delivers a full tidal volume breath in response, ensuring that the patient receives adequate ventilation. This is particularly beneficial for patients who may have weak respiratory drive or are transitioning off of mechanical ventilation.

The key feature of AC mode is its dual capability: while it provides set breaths at a predetermined rate and volume, it also accommodates spontaneous breaths initiated by the patient. This adaptability helps maintain adequate ventilation and reduces the work of breathing, which is vital in critical care settings.

In contrast, the other modes do not implement this dual functionality in the same manner. Synchronized Intermittent Mandatory Ventilation (SIMV) allows for both spontaneous breathing and mandatory breaths but doesn’t guarantee that each patient-initiated breath will be fully supported by the machine. Continuous Positive Airway Pressure (CPAP) primarily maintains airway pressure and supports spontaneous breathing but does not deliver mandatory breaths. Pressure Support Ventilation (PSV) assists only with patient-initiated breaths, providing pressure support without a guaranteed set mandatory volume, which differentiates it