Value of water-soluble contrast (meglumine amidotrizoate) in the diagnosis and management of small bowel obstruction.

INTRODUCTION

The object of the present study was to determine the effectiveness of a water-soluble contrast follow-through study for differentiating complete from incomplete small bowel obstruction (SBO) and for predicting the need for surgery.

METHODS

This prospective study was conducted at Riyadh Medical Complex, Saudi Arabia and spanned 2 years. All adult patients admitted with SBO were included, except those with obstructed hernias, peritonitis, or postabdominal irradiation. The initial resuscitation meglumine amidotrizoate (Gastrografin) follow-though was performed and was considered positive for complete obstruction if the contrast failed to reach the colon as shown on the 24-hour film. Patients were operated on only if they developed signs of strangulation or failed to improve within 48 hours.

RESULTS

Our study group consisted of 73 patients, 48 (65.7%) of whom were male. The mean age was 35.70+/-12.65 years. In 60 (82.2%) patients, contrast reached the ascending colon within 24 hours, giving a definitive diagnosis of incomplete obstruction; among these 60 cases, 49 (81.7%) resolved on conservative management. The other 13 (17.8%) patients were diagnosed as having a complete obstruction; 4 (30.8%) of them were treated conservatively, and 9 (69.2%) underwent surgery. Therefore the sensitivity, specificity, positive predictive value, and negative predictive value for meglumine amidotrizoate follow-through as an indicator for operative treatment of SBO were 45.0, 92.5, 81.7, and 69.2, respectively. The P value using Fisher's exact test was 0.0006.

CONCLUSIONS

We can confidently diagnose complete and incomplete SBO and differentiate one from the other. This accurate diagnosis indicates a high chance of success with conservative management for incomplete obstruction but does not always correlate with the need for surgical intervention.