Overview
Why a Blockage Can Become a Surgical Emergency
A mechanical bowel obstruction occurs when a physical barrier prevents intestinal contents from moving forward.
REx-PN
REx-PN
A mechanical bowel obstruction occurs when a physical barrier prevents intestinal contents from moving forward. Adhesions after abdominal surgery, hernias, tumours, inflammation, and twisting of bowel can all create a blockage. The bowel proximal to the obstruction continues to fill with swallowed air, intestinal fluid, and secretions. It dilates, and pressure within the lumen rises. That pressure causes bowel-wall edema and can progressively impair blood flow. A simple blockage can therefore become strangulation: bowel with compromised perfusion. Untreated ischemia may progress to necrosis, perforation, peritonitis, sepsis, and shock. The clinical priority is not merely to confirm that stool is not passing. It is to determine whether the bowel remains viable.
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