Overview
Obstruction Turns Inflammation into a Surgical Emergency
Appendicitis usually begins when the appendiceal lumen becomes blocked.
REx-PN
REx-PN
Appendicitis usually begins when the appendiceal lumen becomes blocked. Secretions and bacteria remain trapped behind the obstruction, pressure rises inside the narrow tube, and the appendiceal wall becomes inflamed. As pressure compromises blood flow, localized ischemia develops. The wall can then perforate, releasing contaminated material into the surrounding tissues. The clinical danger is not simply abdominal pain. A contained perforation may form a localized abscess, while free leakage can cause generalized peritonitis and sepsis. The patient’s condition can change quickly when inflammation that was initially localized becomes diffuse. Pain often begins near the umbilicus because early visceral pain is poorly localized. As inflammation reaches the parietal peritoneum, pain commonly settles in the right lower quadrant and becomes sharper with movement, coughing, or walking. This progression is suggestive, not mandatory: older adults, pregnant patients, and immunocompromised patients may have less typical findings.
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