A 72-year-old woman with severe ARDS secondary to pneumonia (PaO₂/FiO₂ ratio = 95 on FiO₂ 0.8, PEEP 12 cm H₂O) is deeply sedated and paralyzed. She is currently on Pressure Control Ventilation (PCV) with a set inspiratory pressure of 25 cm H₂O and respiratory rate of 18/min. The bedside chest X-ray shows bilateral consolidation. Over the next 6 hours, her oxygenation worsens (PaO₂/FiO₂ = 75) despite increasing FiO₂ to 1.0 and PEEP to 16 cm H₂O. Which ventilation mode change would provide the best recruitment strategy for this patient?