What happens if a patient exceeds their spontaneous ventilation rate in MMV?

• A. The ventilator will stop providing support
• B. The ventilator will reduce its amount of support
• C. The ventilator will increase tidal volume
• D. The ventilator will alarm

Answer: (B)

In the context of Mandatory Minute Ventilation (MMV), if a patient exceeds their spontaneous ventilation rate, the ventilator reduces its amount of support.

MMV is designed to provide a baseline level of ventilation, ensuring that patients receive a minimum minute volume regardless of their own respiratory effort. When the patient is breathing more frequently than the set spontaneous rate, the ventilator recognizes this increased effort and adjusts its support accordingly. By reducing the amount of assistance (such as the frequency or volume of delivered breaths), the ventilator effectively allows the patient to take more control of their ventilation while still ensuring adequate support if needed.

This function helps to balance between patient-initiated breaths and ventilator-delivered breaths, optimizing the weaning process and promoting patient comfort. Overall, the rationale is to allow the patient’s efforts to be recognized and accommodated without overwhelming them with additional support that might hinder their ability to breathe independently.

The other outcomes, such as stopping support, increasing tidal volume, or alarming, do not align with how MMV is intended to function in response to a patient's respiratory activity. Rather, the ventilator's ability to modulate support is a key feature that allows for a more patient-centered approach to mechanical ventilation.