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

OBJECTIVE: 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.

MATERIALS AND METHODS: 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.

RESULTS: 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.

CONCLUSION: 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.