History An 86-year-old male patient underwent a perforated peptic ulcer repair. A day after the procedure a rise in body temperature was observed in the patient. There was minimal peritoneal soiling at the time of the operation. He has a morphine infusion, but his pain is poorly controlled. A urinary catheter remains from his operation and the urine output is adequate. Prior to his surgery, he was fit, but he was a heavy smoker.

Examination His blood pressure is 130/90 mmHg, pulse rate 110/min, respiratory rate 30/min and temperature 38°C. His saturations have remained at 99 per cent on 24 per cent oxygen. On examination of his chest, bilateral coarse basal crepitations can be heard and the lung bases are dull on percussion. Abdominal examination reveals tenderness around the incision site and the urinalysis is clear. Blood tests and a portable chest x-ray are ordered as shown.…