Self-Evaluation Therapist Multiple-Choice Examination IIQuestion 6A 75 kg male patient is being mechanically ventilated following cardiac surgery. Current ventilator settings are: SIMV mode, rate 12/min, tidal volume 400 mL, FIO2 0.35, PEEP 5 cm H20. Arterial blood gases are obtained and the results are: pH 7.28, PaCO2 59 mm Hg, HCO3 26 mEq/L, Pa02 78 mm Hg. Which of the following should the respiratory therapist INITIALLY recommend?setting the FIO2 at 0.40 setting the tidal volume at 600 mL setting the PEEP at 7.5 cm H20 switching to the assist/control mode