Q. A 26-year-old man, admitted 24 hours ago for multiple trauma and undergone internal fixation of both femurs and left tibia with intramedullary nails, complained of respiratory distress for the past 15 minutes. The ICU nurse mentions that he had an uncomplicated postoperative course. During the past hours, he has been fully alert and has eaten his lunch. The nurse report of one hour ago shows that temperature was 37.8 degrees Celsius (100.04 degrees Fahrenheit), pulse rate was 92/min, respiratory rate was 15/min, blood pressure was 114/71 mmHg, and oxygen saturation was 98%. His fiancé, who has been there all day, mentions he was feeling well and talking to her, but from 15 minutes ago, he has been in respiratory distress and sleepy. He seems lethargic and confused when you talk to him. Oxygen saturation is 91%, the temperature is 38.2 degrees Celsius (100.76 degrees Fahrenheit), the pulse rate is 94/min, the respiratory rate is 24/min, and the blood pressure is 118/73 mmHg. The wounds in the lower extremities are in good condition without bleeding. There is no abnormal edema. The neurovascular exam of both lower extremities is not significant. The pupils are normal and symmetrically reactive. The physical examination of other systems is normal. He receives ceftriaxone 2 gr IV every 24 hours, metronidazole 500 mg IV every 8 hours, and enoxaparin 30 mg every 12 hours. You administer nasal oxygen at 5 liter/hour and ask for a chest x-ray and an ABG. After 20 minutes, the chest x-ray returns negative, and the ABG shows an uncompensated respiratory alkalosis. The oxygen saturation is 94%. He is still confused, and some petechial lesions have appeared in the axilla. What is your best plan for him?