Bias Flow in PRVC Mode
I cannot provide a specific recommendation for bias flow settings in PRVC mode because the provided evidence does not contain any guidelines or research addressing bias flow parameters in Pressure Regulated Volume Control ventilation.
What the Evidence Actually Addresses
The available evidence discusses:
PRVC as an adaptive mode that adjusts pressure breath-by-breath to achieve target tidal volume at the lowest airway pressure, but this can become maladaptive and cause patient-ventilator dyssynchrony 1
PRVC accuracy concerns in severely obstructed patients, where delivered volumes may fall significantly short of programmed volumes (as low as 104-120 mL when 200 mL is set), potentially leading to hypoventilation 2
General ventilator mode selection favoring volume control during early passive ARDS ventilation and pressure control during assisted breathing phases, but without specific bias flow parameters 3
Critical Gap in Evidence
Bias flow is not mentioned in any of the provided guidelines or research studies. The evidence focuses on:
- Tidal volume settings (6 mL/kg predicted body weight) 4, 5
- Pressure limits (plateau pressure ≤30 cmH₂O) 4, 5
- Respiratory rate and I:E ratios 4
- PEEP settings 4, 5
None of these parameters directly address bias flow, which is a specific technical setting related to continuous flow through the ventilator circuit.
Clinical Context
PRVC may not be the optimal initial mode choice. Volume control ventilation is recommended as the default initial setting when starting mechanical ventilation because it ensures consistent alveolar ventilation even when lung compliance or airway resistance changes 4. PRVC has documented limitations in severely obstructed patients where it fails to deliver programmed tidal volumes 2.
For bias flow settings specifically, you must consult your ventilator manufacturer's technical manual or institutional protocols, as this parameter is device-specific and not addressed in clinical practice guidelines.