Small Bowel Obstruction: When Do We Have to Worry?

Small bowel obstruction (SBO) continues to be one of the leading causes of emergency room visits and emergent surgery and is still associated with substantial morbidity and mortality rates. Most patients with SBO are treated successfully with nonoperative management. However, the mortality of SBO ranges from 2% to 8% and may increase to as high as 25% if bowel ischemia is present and there is a delay in surgical management. A challenge in the clinical management is that clinical symptoms and signs and laboratory findings are not sufficiently sensitive or specific to determine which patients with SBO are high risk for vascular compromise and ischemia from strangulation and so need immediate surgery. Imaging studies, conversely, provide invaluable management guidance.
CT is now established as the best imaging technique for the initial assessment of patients suspected of having SBO. CT helps confirm the diagnosis of mechanical SBO, locate the site of obstruction, establish the cause, and detect complications. Studies have sought to identify the CT signs of ischemia that can help accurately predict a need for emergent surgery and anticipate whether bowel resection is necessary.
Furthermore, Imaging could accurately differentiate between open-loop SBO and closed-loop SBO and determine how this difference may influence the management strategy. These issues including other worrisome imaging signs in SBO are discussed and relevant pictures will be illustrated. Finally, the ability of imaging studies to help predict the success or failure of nonoperative management will be demonstrated.
Keywords: small bowel obstruction, CT, strangulation