On postoperative day 3 after a total hip replacement, a 68-year-old woman has abdominal distension, continuous vague discomfort, and vomiting. The abdomen is silent on auscultation with no colicky episodes. Plain radiograph shows gas distributed throughout both small bowel and colon. Which statement correctly distinguishes this condition from mechanical small bowel obstruction?

• A Gas is absent from the large bowel on radiograph
• B Colicky pain with high-pitched tinkling bowel sounds is present
• C Water-soluble contrast fails to reach the colon at 24 hours
• D Both small bowel and colon contain gas, and bowel sounds are absent ✓

Explanation

Postoperative paralytic (adynamic) ileus produces diffuse gaseous distension involving the small bowel and colon together, with absent bowel sounds and continuous rather than colicky pain. Mechanical obstruction shows dilated small bowel loops with collapsed distal bowel, colicky pain, and tinkling sounds. The discriminating radiological fact is gas throughout the whole gut in ileus versus air-fluid levels with colonic collapse in mechanical obstruction.

Reference: Bailey and Love's Short Practice of Surgery, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.