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Closed-loop small-bowel obstruction with suspected ischaemia — MRCEM SBA MCQ

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HardGastrointestinal and surgical emergenciesClosed-loop small-bowel obstruction with suspected ischaemiaMRCEM SBA

A 63-year-old woman presents with eight hours of worsening abdominal pain, vomiting and inability to pass flatus. She underwent an open sigmoid colectomy five years ago. Her blood pressure is 126/78 mmHg, pulse 98/min and venous lactate 1.3 mmol/L. Her abdomen is distended and tender without guarding. Intravenous fluids, analgesia and nasogastric decompression have been started. Contrast-enhanced CT shows small-bowel obstruction with two adjacent transition points enclosing a C-shaped loop. The enclosed bowel has reduced mural enhancement and adjacent mesenteric fluid; there is no free intraperitoneal gas. What is the most appropriate next management plan?

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Correct answer: A — Arrange urgent operative exploration with the emergency general surgical team.

Previous abdominal surgery makes adhesions a plausible cause of the obstruction, but it does not establish that a conservative trial is safe. The two adjacent transition points enclose a closed loop. Reduced enhancement of the enclosed bowel indicates threatened perfusion; both closed-loop configuration and reduced enhancement are CT findings predictive of ischaemia in small-bowel obstruction. ([pubmed.ncbi.nlm.nih.gov](https://pubmed.ncbi.nlm.nih.gov/42053388/)) **A** is therefore the best plan: continue resuscitation and nasogastric decompression while arranging urgent surgical exploration. UK emergency general surgery guidance recommends surgery as soon as possible when ischaemia or strangulation is suspected. Normal lactate, preserved blood pressure, absence of guarding and absence of free gas do not negate the concerning CT findings. **B** is appropriate for selected uncomplicated adhesional obstruction, but observation would delay treatment here. **C** may aid a conservative trial in uncomplicated adhesional obstruction; it must not postpone surgery for suspected ischaemia. **D** might resolve uncertainty after equivocal initial imaging, whereas this CT already identifies the complication that determines management. **E** is an option for selected colonic volvulus, not for a compromised closed loop of small bowel. ([whittington.nhs.uk](https://www.whittington.nhs.uk/document.ashx?id=6115))

Reference: Association of Surgeons of Great Britain and Ireland, Commissioning guide: Emergency general surgery (acute abdominal pain), section 1.8 (April 2014) — https://www.whittington.nhs.uk/document.ashx?id=6115 Diagnostic Performance of Individual CT Signs for Identifying Ischemia and Necrosis in Small Bowel Obstruction: A Systematic Review and Meta-Analysis (August 2026) — https://pubmed.ncbi.nlm.nih.gov/42053388/