Small bowel obstruction

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Last reviewed: 9 Apr 2025
Last updated: 26 Mar 2025

Summary

Definition

History and exam

Key diagnostic factors

  • abdominal pain
  • constipation/failure to pass flatus or stool
  • vomiting
  • abdominal distention
  • abdominal tenderness
  • peritonitis
  • presence of risk factors
  • palpable abdominal mass
Full details

Other diagnostic factors

  • nausea
  • fever
  • tachycardia
  • tachypnea
  • severe lethargy
  • hypotension
  • diarrhea
  • groin swelling
Full details

Risk factors

  • previous abdominal surgery
  • intestinal malignancy
  • malrotation
  • Crohn disease
  • hernia
  • intussusception
  • volvulus
  • intestinal atresia
  • appendicitis
  • foreign body ingestion
Full details

Diagnostic tests

1st tests to order

  • abdominal CT scan
  • CBC
  • BUN
  • electrolyte panel
Full details

Tests to consider

  • abdominal x-rays
  • water-soluble contrast study
  • laparotomy/laparoscopy
  • abdominal ultrasound
  • abdominal MRI
Full details

Treatment algorithm

ACUTE

complicated or strangulated SBO: surgical candidate

complicated or strangulated SBO: surgery not indicated

simple SBO

Contributors

Expert advisers

Adrian Maung, MD, MBA, FACS, FCCM

Associate Professor of Surgery

Division of General Surgery, Trauma and Surgical Critical Care

Department of Surgery

Yale School of Medicine

New Haven

CT

Disclosures

AM declares that he has no competing interests.

Acknowledgements

Dr Adrian Maung would like to gratefully acknowledge Dr John T. Jenkins, Dr Edward T. Pring, Dr George Malietzis, Dr Frances J. McNicol, and Dr David J. Hackam, previous contributors to this topic.

Disclosures

JTJ , ETP, GM, FJM, and DJH declare that they have no competing interests.

Peer reviewers

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

FL

Disclosures

SDW declares that he has no competing interests.

References

Our in-house evidence and editorial teams collaborate with international expert contributors and peer reviewers to ensure that we provide access to the most clinically relevant information possible.

Key articles

Maung AA, Johnson DC, Piper GL, et al; Eastern Association for the Surgery of Trauma. Evaluation and management of small-bowel obstruction: an Eastern Association for the Surgery of Trauma practice management guideline. J Trauma Acute Care Surg. 2012 Nov;73(5 suppl 4):S362-9.Full text  Abstract

Jackson P, Vigiola Cruz M. Intestinal obstruction: evaluation and management. Am Fam Physician. 2018 Sep 15;98(6):362-7. Abstract

American College of Radiology. ACR appropriateness criteria: suspected small-bowel obstruction. 2019 [internet publication].Full text

Ten Broek RPG, Krielen P, Di Saverio S, et al. Bologna guidelines for diagnosis and management of adhesive small bowel obstruction (ASBO): 2017 update of the evidence-based guidelines from the World Society of Emergency Surgery ASBO Working Group. World J Emerg Surg. 2018 Jun 19;13:24.Full text  Abstract

Reference articles

A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.
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