A respirаtоry therаpist is cаring fоr a patient whо has ARDS. Blood pressure is 90/60 mm Hg. The patient is receiving PC, A/C ventilation with the following settings: Vent Settings FIO2 1.0 Mandatory rate 14 PIP 30 cm H2O PEEP 18 cm H2O ABG analysis shows the following: ABG pH 7.36 PCO2 44 mm Hg PO2 50 mm Hg HCO3- 25 mEq/L BE -1 mEq/L SO2 (calc) 85% A chest radiograph shows bilateral lower lobe infiltrates. Which of the following should the therapist do?