Wednesday, July 4, 2018

Limiting Driving Pressure

Pressure Control Setting For Targeting Tidal Volume per Ideal Body Weight [1].

Driving pressure has been shown to be a better determinant of ARDS outcomes than tidal volume, plateau pressure, or PEEP. "A driving pressure > 14 cmH2O was associated with increased 60 day mortality" [1].

Titrating tidal volume to maintain driving pressures < or = to 14 cmH2O with minimal costs in regards to CO2 clearance is a practical strategy to reduce the risk of volutrauma [1].




The practitioner can easily meet this target by utilizing Pressure-control ventilation and never setting the pressure > 14 cmH2O.

The above set of tables "Pressure Control Setting for Targeting Vt/Kg IDBW" displays the relationships between tidal volume, compliance, and pressure control setting (driving pressure). These tables can be used a few ways: 

1. To determine the PC setting to target a specific VT for a measured compliance.
2. If using Volume-control (fully decelerating flow pattern only) or a Adaptive Pressure-control
(e.g. PRVC, Auto-Flow, APV, VC+) predicts what the driving pressure will be for your set VT based on measured compliance. 

3. Titrating tidal volumes to maintain driving pressures < or = to 14 cmH2O.

Inputs- height (inches or centimeters), VT target (4, 5, 6, ml kg), compliance, gender. 
Outputs- IDBW (KG), VT/Kg (ml), Driving pressure. 

REFERENCE
Richey KS. Lung Protective Tabulations, 2018