← Diagnosis and Management Guides
Small Bowel Obstruction
Key considerations: Strangulated/ischemic bowel, Closed-loop obstruction, Perforation
Cannot miss
- Strangulated/ischemic bowel
- Closed-loop obstruction
- Perforation
Likely diagnoses
- Adhesive SBO
- Hernia causing obstruction
- Crohn stricture
- Ileus
Red flags
- Fever
- Peritoneal signs
- Leukocytosis
- Lactate elevation
- CT signs of ischemia
Workup
- history: Prior abdominal surgery, obstipation, nausea/vomiting, crampy abdominal pain; exam: Distension, high-pitched bowel sounds, tenderness, hernia exam; labs: CBC, BMP, lactate, lipase; imaging: CT abdomen/pelvis with IV contrast (identifies transition point and ischemia signs); bedside: KUB: air-fluid levels (less sensitive than CT)
Management
- immediate: NPO, NG tube decompression, IV fluids, pain management; Correct electrolytes; general: Partial SBO: trial of conservative management 24-72hr; Surgical intervention if: complete obstruction, strangulation signs, closed-loop, failure to resolve
Disposition
- admit: All SBO patients; discharge: After resolution of obstruction and return of bowel function; consults: Surgery for all SBO
Clinical pearls
- Absence of gas in rectum on CT = complete SBO
- CT signs of ischemia: reduced wall enhancement, mesenteric haziness, pneumatosis — these need surgery
Source and review
- SAGES SBO Guidelines 2017. Last reviewed: 2024-11-01