Small bowel obstruction is a mechanical disruption in the patency of the gastrointestinal tract.
it is a medical emergency that requires early diagnosis and intervention.
It typically presents with the combined symptoms of abdominal pain, bloating, vomiting, and failure to pass flatus or stool per rectum.
Diagnosis is generally based upon clinical and radiographic features.
Treatment involves a combination of nasogastric decompression and intravenous fluids. Surgery may be required, so the diagnosis requires urgent surgical assessment.
Patients who are treated in a timely manner have a very good prognosis. If untreated, it is often fatal.
Small bowel obstruction (SBO) is a mechanical disruption in the patency of the gastrointestinal tract, resulting in a combination of emesis (that may be bilious), absolute constipation, and abdominal pain.
History and exam
Key diagnostic factors
- constipation/failure to pass flatus or stool
- abdominal pain
- abdominal distention
- abdominal tenderness
- palpable abdominal mass
- palpable rectal mass
Other diagnostic factors
- severe lethargy
- groin swelling
- previous abdominal surgery
- Crohn disease
- intestinal malignancy
- intestinal atresia
- foreign body ingestion
1st investigations to order
- abdominal CT scan
- electrolyte panel
Investigations to consider
- abdominal x-rays
- water-soluble contrast study
- abdominal ultrasound
- abdominal MRI
complete or complicated or strangulated SBO: surgical candidate
complete or complicated or strangulated SBO: surgery contraindicated
John T. Jenkins, MD
Consultant Colorectal Surgeon
Department of Coloproctology
St. Mark's Hospital
JTJ declares that he has no competing interests.
Edward T. Pring, BSc(Hons), MBChB, MRCS
Surgical Registrar and Clinical Research Fellow
St. Mark's Hospital
ETP declares that he has no competing interests.
George Malietzis, MBBS, MSc, MRCS
Honorary Clinical Lecturer
Department of Surgery and Cancer
GM declares that he has no competing interests.
Dr John T. Jenkins, Dr Edward T. Pring, and Dr George Malietzis would like to gratefully acknowledge Dr Frances J. McNicol and Dr David J. Hackam, previous contributors to this topic.
FJM and DJH declare that they have no competing interests.
Steven D. Wexner, MD, FACS, FRCS, FRCS (Ed)
Chief Academic Officer
Emeritus Chief of Staff (1997-2007)
Chairman Department of Colorectal Surgery
Professor of Surgery Ohio State University
Affiliate Professor Department of Surgery
Division of General Surgery
University of South Florida College of Medicine
Cleveland Clinic Florida
SDW declares that he has no competing interests.
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