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Last reviewed: 14 Mar 2025
Last updated: 22 Apr 2024

Summary

Definition

History and exam

Key diagnostic factors

  • constipation/failure to pass flatus or stool
  • risk factors
  • intermittent abdominal pain
  • vomiting
  • abdominal distention
  • abdominal tenderness
  • abdominal mass
  • palpable rectal mass
  • peritonitis

Other diagnostic factors

  • pyrexia
  • nausea (with or without vomiting)
  • tachycardia
  • groin swelling

Risk factors

  • previous abdominal surgery
  • malrotation
  • Crohn's disease
  • hernia
  • appendicitis
  • intestinal malignancy
  • intussusception
  • volvulus
  • intestinal atresia
  • foreign-body ingestion

Diagnostic investigations

1st investigations to order

  • computed tomography
  • water-soluble contrast study
  • arterial blood gases (including lactate)
  • full blood count
  • electrolytes
  • C-reactive protein
  • urea/creatinine ratio
  • serum lipase or amylase
  • glucose
  • clotting, group and save, or cross-match

Investigations to consider

  • urine or serum beta–human chorionic gonadotrophin (HCG)
  • urinalysis
  • ECG
  • magnetic resonance imaging

Treatment algorithm

Contributors

Expert advisers

John Abercrombie, FRCS

General and Colorectal Surgeon

Queen’s Medical Centre

Nottingham

UK

Biography

JA is Clinical Lead for General Surgery, Getting It Right First Time.

Disclosures

JA is trustee and council member of the Royal College of Surgeons of England.

Neena Randhawa, BSc (Hon), MSc, MBChB, FRCS

Consultant Colorectal Surgeon

Royal Victoria Infirmary

Newcastle-upon-Tyne

UK

Disclosures

NR declares she has no competing interests.

Acknowledgements

BMJ Best Practice would like to gratefully acknowledge the previous team of expert contributors, whose work is retained in parts of the content:

John T. Jenkins MD

Consultant Colorectal Surgeon

Department of Coloproctology

St. Mark's Hospital

London

UK

Disclosures: 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

London

UK

Disclosures: ETP declares that he has no competing interests.

George Malietzis

MBBS, MSc, MRCS

Honorary Clinical Lecturer

Department of Surgery and Cancer

Imperial College London

UK

Disclosures: GM declares that he has no competing interests.

Peer reviewers

Malcolm McFall, FRCS

Consultant Colorectal Surgeon

Western Sussex Hospitals NHS Foundation Trust

Chichester

West Sussex

UK

Disclosures

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