Post-Operative Ileus

Post-operative ileus (POI): functional cessation of GI motility post-surgery, lasting >3–5 days (small bowel typically returns within 24h, gastric within 24–48h, colon within 3–5 days). Prolonged POI: >5 days. Symptoms: nausea, vomiting, abdominal distension, no passage of flatus / stool, absent bowel sounds. Distinguish from mechanical obstruction (SBO): • POI: usually all bowel quiet, distension, no specific transition point. • SBO: localised colicky pain, bowel sounds high-pitched / tinkling early, later absent; potential transition point on imaging. Imaging: AXR (dilated loops), CT abdo with contrast (rules out mechanical obstruction, identifies cause).