In ARDS management, what is the primary rationale for using low tidal volumes?

• A. Increasing FiO2
• B. Reducing volutrauma and barotrauma to minimize ventilator-induced lung injury
• C. Maximizing PEEP at all times
• D. Shortening inspiratory time

Answer: (B)

In ARDS, the injured lungs are susceptible to further damage from ventilation if tidal volumes are too large. Delivering normal or high tidal volumes can overdistend already open areas of the lung (volutrauma) and raise pressures inside the chest (barotrauma), which drives further inflammation and ventilator-induced lung injury. Using low tidal volumes—about 6 mL per kilogram of predicted body weight—keeps the alveoli from overdistending and keeps the plateau pressures lower. This protective strategy reduces the risk of additional lung injury and can improve outcomes, even though it may require accepting some permissive hypercapnia and making separate adjustments to PEEP and FiO2 to maintain oxygenation. It’s not primarily about increasing FiO2, maximizing PEEP at all times, or shortening inspiratory time; the central goal is to minimize volutrauma and barotrauma to reduce ventilator-induced lung injury.