A 56-year-old woman presents to the emergency department complaining of abdominal pain. Twenty-four hours previously she developed a continuous pain in the upper abdomen which has become progressively more severe. The pain radiates into the back. She feels nauseated and alternately hot and cold. Her past medical history is notable for a duodenal ulcer which was successfully treated with Helicobacter eradication therapy 5 years earlier. She smokes 15 cigarettes a day, and shares a bottle of wine each evening with her husband. Examination The patient looks unwell and dehydrated.

She weighs 115 kg. She is febrile, 38.5°C, her pulse is 108/min and blood pressure 124/76 mmHg. Cardiovascular and respiratory system examination is normal. She is tender in the right upper quadrant and epigastrium, with guarding and rebound tenderness. Bowel sounds are sparse. A plain abdominal X-ray is also…