Small bowel obstruction in the virgin abdomen: time to challenge surgical dogma with evidence

Background: Although adhesions account for more than 70% of small bowel obstruction (SBO), they are thought to be less likely aetiologies in patients without previous abdominal surgery. Expedient surgery has historically been advocated as prudent management in these patients. Emerging evidence appears to challenge such a dogmatic approach.

Methods: A retrospective analysis was performed in all SBO patients with a virgin abdomen admitted between January 2012 and August 2014. Patients with obstruction secondary to abdominal wall hernias were excluded. Patient demographics, clinical presentation, management strategy and pathology involved were reviewed.

Results: A total of 72 patients were included in the study. The majority of patients were males (66.7%), with a median age of 58 years (range: 23-101). Abdominal pain (97%) and vomiting (86%) were the most common presentations while abdominal distention (60%) and constipation (25%) were reported less frequently. Adhesions accounted for the underlying cause in 44 (62%) patients. Other aetiologies included gallstone ileus (n = 5), phytobezoar (n = 5), intussusception (n = 4), internal herniation (n = 4), newly diagnosed small bowel tumour (n = 3), mesenteric volvulus (n = 3), stricture (n = 3) and Meckel's diverticulum (n = 1). Twenty-nine (40%) patients were successfully managed conservatively while the remaining 43 (60%) underwent surgery. The intraoperative findings were in concordance with the preoperative computed tomography scan in 76% of cases.

Conclusion: Adhesions remain prevalent despite the absence of previous abdominal surgery. Non-operative management is feasible for SBO in a virgin abdomen. Computed tomography scan can be a useful adjunct in discerning patients who may be treated non-operatively by elucidating the underlying cause of obstruction.