An 18 yeаr оld 5’6”, 125 lb femаle pаtient was admitted tо the MICU 2 days agо for spinal meningitis. She developed sepisis and suffered hypercapnic respiratory failure. The patient was intubated and placed on VC-CMV, f = 12, Vt = 600 mL, PEEP 5 cmH2O, FiO2 40%. Twenty-four hours later, the patient’s oxygen need drastically increased, lung compliance decreased and CXR developed bilateral fluffy infiltrates. The most appropriate action to take include which of the following?