Adhesive small bowel obstruction: predictive value of oral contrast administration on the need for surgery.

INTRODUCTION: adhesive small bowel obstruction (SBO) is a common cause of hospital admission. Nonoperative management is initially recommended unless there is suspicion of strangulation, but its optimal duration is controversial. The aims of our study was to evaluate the usefulness of radiographic small bowel examination with contrast medium to predict the need for surgery in SBO.

MATERIAL AND METHODS: this prospective study carried out from January 1999 to December 2001, included 100 patients with clinical and radiological criteria of adhesive SBO. We described the past medical history, as well as clinical picture, blood tests and radiological findings in these patients. Fifty cubic centimeters of 5% barium suspension were given orally, and plain abdominal radiographs were taken at 4, 8, 16, and 24 hours afterwards. A liquid diet was given as soon as the contrast medium appeared in the right colon. Otherwise, surgical intervention was considered based on the outcome of the patient and the criteria of the emergency surgical team.

RESULTS: in 70 patients, barium contrast appeared in the right colon, and a liquid diet was tolerated by 69 of them (98.6%). Mean hospitalization time for this group was 43 +/- 17 hours. In the remaining 30 patients, no evidence of barium contrast in the right colon was seen, and 25 of them underwent surgery (75%), while the other 5 tolerated a liquid diet. Mean hospitalization time for this second group of patients was 13.8 +/- 11 days. Sensitivity, specificity, positive predictive value, and negative predictive value for the absence of contrast medium in the right colon within 24 hours as a predictor of surgery were 93, 96, 98 and 83%, respectively. There was a statistical significant relationship (p < 0.01) between the "Presence of contrast medium in the right colon" and "Oral diet tolerance". Only the variable "Number of previous surgical interventions" tended to reach statistical significance (p = 0.07). Tolerance of liquid diet was more likely when patients had more than one previous abdominal surgery.

CONCLUSIONS: early oral administration of a radiological contrast medium in patients with adhesive SBO can effectively predict the need for a surgical procedure. It can shorten not only hospital stay, but also the potential morbidity of late surgery, secondary to a prolonged and unsuccessful nonoperative treatment.