Small Bowel Obstruction (SBO)

Overview


Plain-Language Overview

A small bowel obstruction (SBO) is a blockage in the small intestine that prevents food, fluids, and gas from moving through normally. This condition affects the digestive system, specifically the small intestine, which is responsible for absorbing nutrients from food. When the bowel is blocked, it can cause symptoms like abdominal pain, vomiting, and constipation. The blockage can be caused by scar tissue, hernias, or tumors. Because the contents cannot pass through, the bowel may become swollen and painful, which can lead to serious complications if untreated. The main health impact is the disruption of digestion and potential damage to the bowel tissue.

Clinical Definition

Small bowel obstruction (SBO) is a clinical syndrome characterized by a mechanical or functional blockage of the small intestine that impairs the normal passage of intestinal contents. The core pathology involves luminal obstruction, commonly caused by adhesions from prior surgery, hernias, or tumors. This leads to proximal bowel dilation, increased intraluminal pressure, and impaired absorption and secretion. Clinically, SBO presents with colicky abdominal pain, vomiting, abdominal distension, and obstipation. It is a surgical emergency if complicated by bowel ischemia or perforation. Early recognition and differentiation from large bowel obstruction are critical for management and prognosis.

Clinical Presentation


Diagnostic Workup


Pathophysiology


Treatments


Prevention


Outcome & Complications


Differential Diagnoses


Medical Disclaimer: The content on this site is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. If you think you may be experiencing a medical emergency, call 911 or your local emergency number immediately. Always consult a licensed healthcare professional with questions about a medical condition.

Artificial Intelligence Use: Portions of this site’s content were generated or assisted by AI and reviewed by Erik Romano, MD; however, errors or omissions may occur.

Analytics Disclosure: If you allow analytics cookies, Doctogenic uses Google Analytics, Microsoft Application Insights, and Microsoft Clarity to understand site usage, diagnose issues, review heatmaps and session replay recordings, and improve the service on pages where those tools are enabled. Clarity is not enabled on account, purchase, billing, checkout, Stripe-related, or admin pages. You can change this choice through Cookie preferences.

USMLE® is a registered trademark of the Federation of State Medical Boards (FSMB) and the National Board of Medical Examiners (NBME). Doctogenic and Roscoe & Romano are not affiliated with, sponsored by, or endorsed by the USMLE, FSMB, or NBME. Neither FSMB nor NBME has reviewed or approved this content. "USMLE Step 1" and "USMLE Step 2 CK" are used only to identify the relevant examinations.