|NORMAL||PIP or Ppeak (<35 cm H2O)|
|DEFINITION||Highest (peak) proximal airway pressure reached during inspiration.|
|MECHANICS||Keep PIP < 35 cm H2O
In VV – machine VT, VI, PEEP, and patient CLT and Raw determines PIP.
In PV – PIP is a set pressure limit; PIP + CLT + Raw = VT
↑ PIP → ↑ VT, Paw, and Palv (except in high Raw where the ↑ pressure is lost to the airway and may not reach the alveoli)
PIP is used to calculate Cdyn and Raw.
|VENTILATION EFFECTS||↑ PIP (VT) → ↓ PaCO2|
|OXYGENATION||↑ PIP (Paw) → ↑ PaO2|
PIP Precautions –
Too low a PIP may result in hypoventilation and atelectasis.
Too high a PIP can increase the risk of barotrauma, compromise both ventilation and oxygenation effects, and significantly compromise hemodynamics.