Acute Caremiddle twist
A 58-year-old man is admitted with three days of fever and a productive cough. He weighs 138 kg, uses continuous positive airway pressure at home for witnessed apnoeas, and falls asleep mid-conversation during the day. He has never smoked and has no diagnosed lung disease. He is alert and speaking in short phrases. Respiratory rate 26, heart rate 104, blood pressure 132/78 mmHg, oxygen saturation 86% on room air. Coarse crackles are heard at the right base. Which one of the following is the most appropriate way to begin his oxygen?