Case presentation

A 59-year-old woman presents to the emergency department with 3 days of diffuse abdominal pain with profuse nausea and vomiting. The pain came on gradually and worsens after eating. The patient’s last bowel movement was 3 days ago and she has not passed gas in a day. She has not had any fever, blood in her stool or vomit, or any urinary discomfort.

Past medical history—dyslipidaemia, hypothyroidism. Past surgical history—partial bowel resection after bowel obstruction 40 years ago. Medications—levothyroxine, ezetimibe, rosuvastatin, aspirin.

Triage vital signs

Blood pressure 140/77 mm Hg, heart rate 94 bpm, temperature 36.8°C, respiratory rate 18, oxygen saturation 96%.

Physical examination

An uncomfortable appearing patient with mild tenderness to palpation in all abdominal quadrants, and maximal tenderness in the left lower quadrant without guarding. The patient’s abdomen is non-distended but is tympanitic to percussion.

Questions

1. What is the usefulness of point-of-care ultrasound (POCUS) in the evaluation for suspected small bowel obstruction (SBO)?

SBO is one of the most common intestinal emergencies, accounting for 15–20% of all patients admitted to surgical wards from the emergency department.1 2 CT is the 'gold standard' imaging modality for suspected SBO given its superior diagnostic accuracy, its ability to differentiate between ileus and obstruction, and its capacity to identify signs of intestinal ischaemia suggesting a need for emergent surgery.3–5 However, CT is costly and time intensive, exposes the patient to ionising radiation and may not be universally available. In view of these limitations, abdominal radiography is a commonly used examination for SBO despite being only 50–70% sensitive for detecting obstruction.1 6–9

In contrast, bedside ultrasound has emerged as an ideal screening modality for SBO, with many studies demonstrating a sensitivity of 91–100% in comparison with CT.1 4 …