A mechanical bowel obstruction is a partial or complete blockage in the intestine, which is also called the bowel. Blockages can occur at any point along the small or large bowel. They are more common in the small bowel. When the bowel is blocked, food and liquid cannot pass through. Over time, food, liquid, and gas build up in the area above the blockage.

Mechanical Bowel Obstruction
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Most small bowel blockages are due to adhesions. An adhesion is a band of scar tissue that causes the bowel to attach to the abdominal wall or other organs. Most large bowel obstructions are caused by tumors.

Specific causes of bowel obstructions include:

  • Hernia
  • Tumors
  • Bowel inflammation or swelling
  • Foreign matter in the intestines
  • Gallstones
  • Impacted feces
  • Volvulus—twisting of the intestine
  • Intussusception —when the intestine pulls inward into itself
  • Scar tissue from a previous abdominal or pelvic surgery, particularly gynecologic or gastrointestinal operations