Which of the following is an example of a feature of assist-controlled ventilation?

• A. Mandatory breaths only
• B. Spontaneous breaths only
• C. Combination of mandatory and spontaneous breaths
• D. No breaths provided

Answer: (C)

Assist-controlled ventilation is a mode of mechanical ventilation that allows for a combination of mandatory and spontaneous breaths. In this mode, the ventilator delivers a set tidal volume for each mandatory breath, while also enabling the patient to initiate additional spontaneous breaths if they are capable. The set tidal volume ensures that the patient receives adequate ventilation even if their own respiratory effort is insufficient. This feature is particularly beneficial for patients who may fluctuate in their ability to breathe independently, as it helps maintain adequate ventilation and oxygenation while allowing for some degree of patient control.

In contrast, other options do not fully reflect the characteristics of this mode. The choice depicting only mandatory breaths would lack the integration of spontaneous efforts by the patient, which is crucial in assist-controlled ventilation. Similarly, a focus on spontaneous breaths alone would disregard the ventilator's role in providing necessary mechanical support. Lastly, the idea of providing no breaths contradicts the purpose of mechanical ventilation, as it is meant to assist or completely take over the respiratory function as needed. This understanding of assist-controlled ventilation highlights how it effectively accommodates both mandatory and optional respiratory efforts, providing versatility in patient care.