Bowel obstruction
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An introductory overview for this topic. The article introduction is reproduced here, so you do not need to leave MedAtlas to read it. It may not match the latest official medical guidance.
Bowel obstruction, also known as intestinal obstruction, is a mechanical or functional obstruction of the intestines that prevents the normal movement of the products of digestion. Either the small bowel or large bowel may be affected. Signs and symptoms include abdominal pain, vomiting, bloating and not passing gas. Mechanical obstruction is the cause of about 5 to 15% of cases of severe abdominal pain of sudden onset requiring admission to hospital.
Causes of bowel obstruction include adhesions, hernias, volvulus, endometriosis, inflammatory bowel disease, appendicitis, tumors, diverticulitis, ischemic bowel, tuberculosis and intussusception. Small bowel obstructions are most often due to adhesions and hernias, while large bowel obstructions are most often due to tumors and volvulus. The diagnosis may be made on plain X-rays; however, CT scan is more accurate. Ultrasound or MRI may help in the diagnosis of children or pregnant women.
The condition may be treated conservatively or with surgery. Typically intravenous fluids are given, a nasogastric (NG) tube is placed through the nose into the stomach to decompress the intestines, and pain medications are given. Antibiotics are often given. In small bowel obstruction about 25% require surgery. Complications may include sepsis, bowel ischemia and bowel perforation.
About 3.2 million cases of bowel obstruction occurred in 2015, which resulted in 264,000 deaths. Both sexes are equally affected and the condition can occur at any age. Bowel obstruction has been documented throughout history, with cases detailed in the Ebers Papyrus of 1550 BC and by Hippocrates.
How this connects to General Surgery
Molecular investigation links DNA variation and gene regulation to RNA, proteins and cellular function. Assays measure selected molecular features with finite sensitivity and specificity; a detected variant or transcript does not automatically establish biological causation or a clinical diagnosis.
Text credit: Wikipedia contributors, “Bowel obstruction”, original article · authors & revision history · CC BY-SA 4.0. Unmodified opening extract, accessed 24 September 2026. This Wikipedia-derived section is provided under CC BY-SA 4.0; the independent MedAtlas notes and design are separate works.
Bowel obstruction · visual study map
Scalable vector illustration. Labeled conceptual map, not a precise anatomical, histological or diagnostic image.The wording in this learning map is adapted from the attributed Wikipedia background section below (CC BY-SA 4.0).
What the underlying subject studies
Surgery concerns anatomical conditions for which operative and nonoperative strategies may be considered. Understand the region, potential pathology, tissue blood supply, wound response and overall patient health before thinking about procedures.
How mechanisms and evidence connect
The perioperative period includes assessment, informed consent, infection prevention, physiological support, operative planning, recovery and follow-up. Technical procedures depend on specialist training and case-specific risk.
How to develop a sound explanation
Use a sequence diagram to connect indication, anatomy, pathophysiology and anticipated complications. A conceptual figure here is not a guide to performing an operation or managing an emergency.
References and verification (optional)
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