Which ventilation mode allows patients to self-regulate rate and depth of breaths while delivering preset volumes?

Synchronized intermittent mandatory ventilation (SIMV) is a mode that allows patients to have a degree of autonomy in their breathing while also receiving a set number of mandatory breaths. In SIMV, the ventilator provides a certain number of mandatory breaths, but the patient can initiate additional breaths on their own at any time. These patient-initiated breaths can vary in both rate and depth, allowing for self-regulation of ventilation.

This mode is particularly beneficial in allowing patients to gradually take over control of their breathing, making it ideal during weaning from mechanical ventilation. While the mandatory breaths are delivered at a preset tidal volume, the spontaneous breaths taken by the patient can vary in volume according to their own needs.

The other options present different approaches to mechanical ventilation. Assist-control ventilation provides a set tidal volume with some patient-triggered breaths but may lead to hyperventilation if patients trigger extra breaths frequently. Pressure support ventilation allows patients to initiate breaths but relies solely on pressure rather than volume control. Pressure-controlled inverse ratio ventilation is used in specific situations, such as ARDS, to improve oxygenation but does not offer the same level of patient self-regulation as SIMV. Thus, SIMV stands out as the correct choice for allowing both self-regulation of