Last reviewed: December 2018
Last updated: April  2018



History and exam

Key diagnostic factors

  • presence of risk factors
  • nausea and vomiting
  • abdominal distention
  • no features of mechanical obstruction or peritoneal inflammation (e.g., abdominal hernia, peritoneal signs)

Other diagnostic factors

  • obstipation (severe constipation with no passage of stool or flatus)
  • discomfort and abdominal cramping
  • decreased or hypoactive bowel sounds
  • hypovolaemia

Risk factors

  • abdominal surgery
  • non-abdominal surgery
  • acute/systemic illness (e.g., MI, pneumonia, acute cholecystitis, pancreatitis, sepsis, multi-organ trauma)
  • electrolyte imbalance
  • opioid analgesics, anticholinergics, or anaesthetic gases
  • comorbidities (e.g., diabetes mellitus, cardiovascular insufficiency, Chagas disease, scleroderma)

Diagnostic investigations

1st investigations to order

  • serum electrolytes
  • serum magnesium
  • FBC
  • abdominal x-ray
Full details

Investigations to consider

  • serum LFTs
  • serum amylase
  • serum lipase
  • serum albumin and pre-albumin
  • abdomen and pelvis CT scan (with intravenous contrast and oral water-soluble contrast)
  • small bowel series
  • gastric emptying study
Full details

Treatment algorithm


Authors VIEW ALL

Steven D. Wexner


Digestive Disease Center

Professor and Chair

Department of Colorectal Surgery

Cleveland Clinic




SDW has received consulting fees, stock options, and royalties from the following companies. These relationships are ongoing. Consulting - Axonics Medical, Intuitive Surgical, Karl Storz Endoscopy America, LifeBond, Medtronic, Novadaq, TiGenix. Stock options - Asana Medical, LifeBond, Pragma, Renew Medical. Royalties - Covidien, Intuitive Surgical, Karl Storz Endoscopy America, Unique Surgical Innovations. Inactive consulting agreements, but stock options retained for prior consulting - CRH Medical, Intuitive Surgical, Neatstitch, novoGI. There are no relevant disclosures to the submitted work.

Colorectal and Minimally Invasive Surgery

Division of General Surgery

Toronto Western Hospital

Assistant Professor

Department of Surgery

University of Toronto





ASC declares that he has no competing interests.

Dr Steven D. Wexner and Dr Ahmed Sami Chadi would like to gratefully acknowledge Dr Paula I. Denoya, a previous contributor to this monograph. PID declares that she has no competing interests.

Peer reviewers VIEW ALL

Associate Professor of Pediatric Surgery

University of Pittsburgh School of Medicine




DJH declares that he has no competing interests.

Consultant Colorectal Surgeon

St. Mark's Hospital




JJ declares that he has no competing interests.

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