Conventional ventilation with distending pressure is used to recruit atelectatic alveoli. An often-used alternative therapy in this setting is which of the following?

• A. High-frequency ventilation
• B. Nasal continuous positive airway pressure
• C. Surfactant therapy
• D. Extracorporeal membrane oxygenation

Answer: (A)

High-frequency ventilation promotes alveolar recruitment while minimizing lung injury. It achieves this by delivering very small tidal volumes at a very high rate, so effective ventilation comes from maintaining a higher mean airway pressure that keeps collapsed alveoli open. Because the breaths are tiny, the risk of volutrauma and barotrauma is reduced compared with conventional ventilation, making it a preferred alternative when the goal is to recruit atelectatic units without overdistension. Noninvasive CPAP helps keep airways open but doesn’t provide a distinct ventilatory mode to recruit as an alternative to conventional ventilation; surfactant helps reduce surface tension but isn’t a ventilation strategy, and ECMO is reserved for more severe, refractory cases.