Large bowel obstruction

Last reviewed: 24 Aug 2023
Last updated: 16 Aug 2022



History and exam

Key diagnostic factors

  • colicky abdominal pain
  • abdominal distention
  • tympanic abdomen
  • change in bowel habits
  • hard feces
  • empty rectum
  • soft stools
  • recent weight loss
  • rectal bleeding
  • abnormal bowel sounds
  • palpable rectal mass
  • palpable abdominal mass
  • positive fecal occult blood test
  • fever
  • abdominal tenderness
  • abdominal rigidity
More key diagnostic factors

Other diagnostic factors

  • tenesmus
  • history of radiotherapy
  • history of gynecologic symptoms
  • nausea and vomiting
  • groin swelling
  • pelvic mass
  • ingestion of foreign body
Other diagnostic factors

Risk factors

  • older age
  • female sex
  • institutionalization
  • mental illness
  • megacolon
  • low or high dietary fiber
  • previous colorectal resection
  • previous abdominal surgery
  • inflammatory bowel disease
  • laxative abuse
  • diabetes
More risk factors

Diagnostic investigations

1st investigations to order

  • CBC
  • serum electrolytes
  • renal function
  • serum amylase/lipase
  • coagulation studies
  • plain abdominal x-ray
More 1st investigations to order

Investigations to consider

  • CT abdomen and pelvis
  • contrast enema
  • flexible/rigid endoscopy
  • biopsy
More investigations to consider

Treatment algorithm


acutely ill


sigmoid volvulus

cecal volvulus

colorectal malignancy

diverticular disease

foreign body ingestion

benign strictures


pelvic abscess



Adrian A. Maung, MD, FACS, FCCM

Associate Professor of Surgery

Division of General Surgery, Trauma and Surgical Critical Care

Department of Surgery

Yale School of Medicine

Surgical Director of Perioperative Services

Adult Trauma Medical Director

Yale New Haven Hospital

New Haven



AAM declares that he has no competing interests.


Dr Adrian A. Maung would like to gratefully acknowledge Dr George Malietzis, Dr John T. Jenkins, and Dr Alisdair J. MacDonald, previous contributors to this topic.


GM, JTJ, and AJM declare that they have no competing interests.

Peer reviewers

Alessandro Fichera, MD, FACS, FASCRS

Assistant Professor

Department of Surgery

University of Chicago




AF declares that he has no competing interests.

Robert H. Diament, MD

Consultant Surgeon

Crosshouse Hospital





RHD declares that he has no competing interests.

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