Abdominal radiography findings in small-bowel obstruction: relevance to triage for additional diagnostic imaging

Our aim was to determine which findings on abdominal radiography are relevant for distinguishing complete or high-grade partial small-bowel obstruction from low-grade partial or no small-bowel obstruction.

Admitting abdominal radiographs with the patients in the supine and upright positions were scored for 25 different findings in 81 patients with clinically suspected small-bowel obstruction. Forty-one patients had complete or high-grade partial small-bowel obstruction, and 40 had low-grade partial small-bowel obstruction or no obstruction as determined by enteroclysis examination. Abdominal radiography findings were subjected to statistical analysis for correlation with degree of obstruction.

Of 12 radiographic findings strongly associated (p < 0.05) with the severity of obstruction, two findings were found to be the most significant (p < or = 0.0003) and predictive of a higher grade small-bowel obstruction: the presence of air-fluid levels of differential height in the same small-bowel loop and the presence of a mean air-fluid level width greater than or equal to 25 mm on upright abdominal radiographs.

When both critical findings are present, the degree of small-bowel obstruction is likely high-grade or complete. When both signs are absent, small-bowel obstruction is likely low-grade or nonexistent. Upright abdominal radiographs are important in the examination of patients with suspected small-bowel obstruction and may contribute to the imaging triage of these patients.