Last reviewed: 28 Feb 2023
Last updated: 01 Mar 2019



History and exam

Key diagnostic factors

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

Other diagnostic factors

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

Risk factors

  • abdominal surgery
  • nonabdominal surgery
  • acute/systemic illness (e.g., myocardial infarction, pneumonia, acute cholecystitis, pancreatitis, sepsis, multiorgan trauma)
  • electrolyte imbalance
  • opioid analgesics, anticholinergics, or anesthetic gases
  • comorbidities (e.g., diabetes mellitus, cardiovascular insufficiency, Chagas disease, scleroderma)
More risk factors

Diagnostic investigations

1st investigations to order

  • serum electrolytes
  • serum magnesium
  • CBC
  • abdominal x-ray
More 1st investigations to order

Investigations to consider

  • serum LFTs
  • serum amylase
  • serum lipase
  • serum albumin and prealbumin
  • abdomen and pelvis CT scan (with intravenous contrast and oral water soluble contrast)
  • small bowel series
  • gastric emptying study
More investigations to consider

Treatment algorithm


postoperative ileus

nonsurgical cause


ileus lasting longer than 3 days or prolonging the postoperative recovery



Steven D. Wexner, MD, PhD (Hon), FACS, FRCS, FRCS (Ed), FRCSI (Hon)
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 - Intuitive Surgical, Karl Storz Endoscopy America, Medtronic, TiGenix. Royalties - Covidien, Intuitive Surgical, Karl Storz Endoscopy America, Unique Surgical Innovations. There are no relevant disclosures to the submitted work.


Dr Steven D. Wexner would like to gratefully acknowledge the contribution of Dr Stephen P. Sharp to the update for this topic. Dr Wexner would also like to acknowledge Dr Ahmed Sami Chadi, and Dr Paula I. Denoya, previous contributors to this topic.


SPS, ASC, and PID declare that they have no competing interests.

Peer reviewers

David J. Hackam, MD, PhD

Associate Professor of Pediatric Surgery

University of Pittsburgh School of Medicine




DJH declares that he has no competing interests.

John Jenkins, MB CHB, FRCP

Consultant Colorectal Surgeon

St. Mark's Hospital




JJ declares that he has no competing interests.

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