Overview

Bowel obstruction, also called intestinal obstruction, occurs when the normal flow of intestinal contents is partly or completely blocked. The blockage can be mechanical — a physical barrier — or functional, when the intestine cannot move contents despite being open. Either the small intestine or the large intestine may be involved, and both types have distinct clinical features and management considerations. For more general context see intestinal obstruction.

Signs and symptoms

Common complaints include crampy abdominal pain, nausea, repeated vomiting, visible abdominal swelling or bloating, and failure to pass stool or flatus such as not passing gas. Disturbance of bowel function often leads to dehydration and electrolyte imbalance. Patients may describe inability to tolerate oral intake and progressive discomfort that depends on the level and completeness of the obstruction. Symptoms reflect interruption of the normal products of digestion moving through the gut.

Causes and types

Causes vary by age and region but commonly include:

  • Postoperative adhesions (scar bands) that tether loops of bowel
  • Hernias that trap intestine in the abdominal wall
  • Tumors narrowing the lumen
  • Volvulus (twisting) and intussusception (telescoping) of bowel segments
  • Inflammatory strictures from Crohn disease or diverticulitis

Small-bowel obstruction often causes more vomiting and rapid dehydration, while large-bowel obstruction typically produces distension and constipation.

Diagnosis

Evaluation combines clinical examination with imaging and laboratory tests. Plain abdominal X-rays may show air-fluid levels and dilated loops; computed tomography (CT) provides more detailed information about level, cause, and complications such as ischemia. Contrast studies and ultrasound are useful in selected patients. Blood tests assess dehydration, infection, and organ function. Timely diagnosis helps prevent progression to strangulation or perforation.

Treatment and prognosis

Initial management stabilises the patient with fluid resuscitation, correction of electrolytes, and bowel rest. A nasogastric tube may relieve proximal distension. Some partial obstructions resolve with conservative care; others require urgent surgery to remove the blockage, repair hernias, resect nonviable bowel, or relieve strangulation. Complications include bowel ischemia, perforation, sepsis, and prolonged hospitalization. Outcomes depend on cause, patient health, and speed of treatment.

History and notable facts

Recognition of intestinal obstruction dates back to ancient medicine, but major advances came with antiseptic surgery, anesthesia, and modern imaging, which reduced mortality and improved decision-making. Prevention focuses on minimizing postoperative adhesions and prompt management of hernias and tumors. For further reading on clinical guidelines and summaries see abdominal pain resources, general references at clinical symptom guides, and broader overviews via digestive system references or surgical condition summaries.