What are the characteristics of PRVC regarding trigger, limit, and cycle?

• A. Patient-triggered, flow-limited, time-cycled
• B. Pressure-triggered, time-limited, volume-cycled
• C. Patient or time-triggered, pressure-limited, time-cycled
• D. Flow-triggered, volume-limited, patient-cycled

Answer: (C)

PRVC, or Pressure Regulated Volume Control, is a mode of mechanical ventilation that has specific characteristics related to how it responds to patient needs. In this mode, the ventilator can be patient-triggered or time-triggered, which allows for flexibility in responding to the patient's breathing efforts or automatically providing breaths at set intervals if the patient does not initiate a breath.

The pressure-limited aspect means that during each breath, the ventilator regulates the inhalation pressure to achieve a predetermined tidal volume, but it will not exceed a set pressure limit. This is crucial because it protects the lungs from over-distension and barotrauma while still ensuring that a sufficient volume of air is delivered.

The time-cycled characteristic indicates that the ventilator will switch from the inspiratory phase to the expiratory phase after a set duration, ensuring that the breath duration is controlled and consistent according to the clinician's settings.

This unique combination of being both patient or time-triggered, pressure-limited, and time-cycled helps balance patient comfort and safety, allowing for effective ventilation while adapting to the varying needs of patients with different respiratory patterns.