Which ventilator strategy is considered lung-protective in ARDS?

• A. Low tidal volume ventilation
• B. High tidal volume ventilation
• C. No PEEP
• D. High FiO2 without PEEP

Answer: (A)

Lung-protective ventilation in ARDS centers on using smaller breaths to minimize further injury to the damaged lungs. By delivering lower tidal volumes, about 6 ml per kilogram of predicted body weight, the risk of overdistension (volutrauma) of already stiff and heterogeneous lung tissue is reduced. This style also helps keep plateau pressures at or below roughly 30 cm H2O, which further limits pressure-related injury. To maintain oxygenation when volumes are small, positive end-expiratory pressure (PEEP) is used to keep alveoli open and prevent repeated collapse, and a bit of permissive hypercapnia is acceptable if the bicarbonate balance and pH stay reasonably safe.

Other approaches like using high tidal volumes force more air into already stretched alveoli, increasing volutrauma and further lung injury. Starting with no PEEP leads to alveolar collapse and unstable oxygenation, which worsens injury from repeated opening and closing. Relying on high FiO2 without PEEP can cause oxygen toxicity and still doesn’t prevent collapse. So the strategy that minimizes lung stretch while maintaining safe pressures and using PEEP to keep alveoli open is the lung-protective approach.