Small bowel obstruction
Small bowel obstruction, abbreviated SBO, is a common pathology managed by general surgeons.
This article gives an overview of SBOs. Its primary focus is benign causes of SBO that have nonspecific pathologic findings.
- Radiologic/clinical diagnosis.
- The conventional thinking is the sun should never set on a SBO in a virgin abdomen, i.e. a laparotomy is required to exclude serious pathology in an unoperated abdomen.
- Approximately 10% of virgin (or previously unoperated) abdomens (in a series from 2014) had an unknown malignancy as the underlying cause.
The usual causes of bowel obstruction (large & small) are (mnemonic) SHAVING:
- Adhesions > hernias > neoplasms.
In the context of bowel obstructions and IBD, pathologists often see resected stomas (that were put in place emergently). These specimens are usually fairly straight forward.
- Air-fluid levels.
- +/-Bowel contorted.
- +/-Luminal narrowing +/-proximal dilation.
- +/-Serosal exudate.
- Suggestive of perforation.
- +/-Adhesions (serosal).
- Dense fibrous tissue replaces the adipose tissue.
- +/-Increased vascularity.
- +/-Submucosal fibrosis.
- +/-Serositis - seen in small bowel perforation.
- +/-Foreign body-type granuloma - due to previous surgical intervention.
- Small bowel adenocarcinoma - most important differential diagnosis.
- Metastatic adenocarcinoma - classically on the serosal aspect.
- Signet ring cell carcinoma.
Small Bowel, Resection: - Small bowel wall with focal ischemia and fibrous adhesions, surgical margins appear viable. - NEGATIVE for significiant vascular disease in vessels examined. - NEGATIVE for malignancy.
SMALL BOWEL, RESECTION: - SMALL BOWEL WITH FIBROUS ADHESIONS (EXTENSIVE) ASSOCIATED WITH FOCAL LUMINAL NARROWING. - NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.
SMALL BOWEL, RESECTION: - SMALL BOWEL WITH FIBROUS ADHESIONS (EXTENSIVE), FOCAL LUMINAL NARROWING AND A FOREIGN BODY-TYPE GRANULOMA. - NEGATIVE FOR DYSPLASIA AND NEGATIVE FOR MALIGNANCY.
SMALL BOWEL, RESECTION: - SMALL BOWEL WITH ISCHEMIC CHANGES, FIBROUS ADHESIONS, FOCAL SEROSITIS AND MURAL MICROABSCESS FORMATION. - NO SIGNIFICANT VASCULAR PATHOLOGY APPARENT. - NEGATIVE FOR MALIGNANCY.
- Beardsley, C.; Furtado, R.; Mosse, C.; Gananadha, S.; Fergusson, J.; Jeans, P.; Beenen, E. (Aug 2014). "Small bowel obstruction in the virgin abdomen: the need for a mandatory laparotomy explored.". Am J Surg 208 (2): 243-8. doi:10.1016/j.amjsurg.2013.09.034. PMID 24565365.
- URL: http://www.emedicine.com/EMERG/topic66.htm. Accessed on: 19 April 2011.
- Greenwald, J.; Heng, M. (2007). Toronto Notes for Medical Students 2007 (2007 ed.). The Toronto Notes Inc. for Medical Students Inc.. pp. GS21. ISBN 978-0968592878.