What is the plateau pressure target in ARDS lung-protective ventilation?

• A. ≤25 cm H2O
• B. ≤40 cm H2O
• C. ≤30 cm H2O
• D. ≤50 cm H2O

Answer: (C)

Plateau pressure reflects the pressure in the alveoli when air flow is momentarily stopped at the end of inspiration, isolating the elastic recoil of the lung from airway resistance. In ARDS, the lungs are stiff and more prone to overdistension, so keeping this pressure low protects against volutrauma and barotrauma. The goal is 30 cm H2O or less, because exceeding this level increases the risk of alveolar injury during tidal ventilation. This measurement is obtained with an inspiratory hold to let pressures equilibrate, and it guides how we set tidal volume—usually at about 6 mL/kg predicted body weight—and how we adjust PEEP. If plateau pressure would rise above 30, you lower tidal volume or adjust PEEP (and consider other strategies for severe cases). The key idea is that limiting plateau pressure reduces the distending pressure across alveoli, improving safety in lung-protective ventilation.