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Related to ileus: postoperative ileus




Ileus is a partial or complete non-mechanical blockage of the small and/or large intestine. The term "ileus" comes from the Latin word for colic.


There are two types of intestinal obstructions, mechanical and non-mechanical. Mechanical obstructions occur because the bowel is physically blocked and its contents can not pass the point of the obstruction. This happens when the bowel twists on itself (volvulus) or as the result of hernias, impacted feces, abnormal tissue growth, or the presence of foreign bodies in the intestines.
Unlike mechanical obstruction, non-mechanical obstruction, called ileus or paralytic ileus, occurs because peristalsis stops. Peristalsis is the rhythmic contraction that moves material through the bowel. Ileus is most often associated with an infection of the peritoneum (the membrane lining the abdomen). It is one of the major causes of bowel obstruction in infants and children.
Another common cause of ileus is a disruption or reduction of the blood supply to the abdomen. Handling the bowel during abdominal surgery can also cause peristalsis to stop, so people who have had abdominal surgery are more likely to experience ileus. When ileus results from abdominal surgery the condition is often temporary and usually lasts only 48-72 hours.
Ileus sometimes occurs as a complication of surgery on other parts of the body, including joint replacement or chest surgery.
Ileus can also be caused by kidney diseases, especially when potassium levels are decreased. Heart disease and certain chemotherapy drugs, such as vinblastine (Velban, Velsar) and vincristine (Oncovin, Vincasar PES, Vincrex), also can cause ileus. Infants with cystic fibrosis are more likely to experience meconium ileus (a dark green material in the intestine). Over all, the total rate of bowel obstruction due both to mechanical and non-mechanical causes is one in one thousand people (1/1,000).

Causes and symptoms

When the bowel stops functioning, the following symptoms occur:
  • abdominal cramping
  • abdominal distention
  • nausea and vomiting
  • failure to pass gas or stool


When a doctor listens with a stethoscope to the abdomen there will be few or no bowel sounds, indicating that the intestine has stopped functioning. Ileus can be confirmed by x rays of the abdomen, computed tomography scans (CT scans), or ultrasound. It may be necessary to do more invasive tests, such as a barium enema or upper GI series, if the obstruction is mechanical. Blood tests also are useful in diagnosing paralytic ileus.
Barium studies are used in cases of mechanical obstruction, but may cause problems by increasing pressure or intestinal contents if used in ileus. Also, in cases of suspected mechanical obstruction involving the gastrointestinal tract (from the small intestine downward) use of barium x rays are contraindicated, since they may contribute to the obstruction. In such cases a barium enema should always be done first.


Patients may be treated with supervised bed rest in a hospital and bowel rest. Bowel rest means that nothing is taken by mouth and patients are fed intravenously or through the use of a nasogastric tube. A nasogastric tube is a tube inserted through the nose, down the throat, and into the stomach. A similar tube can be inserted in the intestine. The contents are then suctioned out. In some cases, especially where there is a mechanical obstruction, surgery may be necessary.
Drug therapies that promote intestinal motility (ability of the intestine to move spontaneously), such as cisapride and vasopressin (Pitressin), are sometimes prescribed.

Alternative treatment

Alternative practitioners offer few treatment suggestions, but focus on prevention by keeping the bowels healthy through eating a good diet, high in fiber and low in fat. If the case is not a medical emergency, homeopathic treatment and traditional Chinese medicine can recommend therapies that may help to reinstate peristalsis.


The outcome of ileus varies depending on its cause.


Most cases of ileus are not preventable. Surgery to remove a tumor or other mechanical obstruction will help prevent a recurrence.
Some measures that have been recommended to minimize the severity of postoperative ileus or shorten its duration include making sure that any electrolyte imbalances are corrected, and using nonopioid medications to relieve pain, as opioid drugs (including morphine, oxycodone, and codeine) tend to cause constipation. One group of drugs that shows promise for treating abdominal pain is a class of medications known as kappa-opioid agonists. As of 2004, however, these drugs are still under investigation for controlling visceral pain in humans.



Beers, Mark H., MD, and Robert Berkow, MD, editors. "Ileus." Section 3, Chapter 25. In The Merck Manual of Diagnosis and Therapy. Whitehouse Station, NJ: Merck Research Laboratories, 2004.


Baig, M. K., and and S. D. Wexner. "Postoperative Ileus: A Review." Diseases of the Colon and Rectum 47 (April 2004): 516-526.
Lassandro, F., N. Gagliardi, M. Scuderi, et al. "Gallstone Ileus Analysis of Radiological Findings in 27 Patients." European Journal of Radiology 50 (April 2004): 23-29.
Pavone, P., T. Johnson, P. S. Saulog, et al. "Perioperative Morbidity in Bilateral One-Stage Total Knee Replacements." Clinical Orthopaedics and Related Research 421 (April 2004): 155-161.
Riviere, P. J. "Peripheral Kappa-Opioid Agonists for Visceral Pain." British Journal of Pharmacology 141 (April 2004): 1331-1334.


"Bowel Paralysis." Trigan Oncology Associates Page.
"Intestinal Obstruction." 〈〉.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.


failure of appropriate forward movement of bowel contents. It may be secondary to either mechanical obstruction of the bowel (mechanical ileus) or a disturbance in neural stimulation (adynamic ileus). Ileus is a surgical emergency that may or may not require surgical intervention; the cause needs to be established promptly.

Adynamic (or paralytic) ileus often accompanies peritonitis and is also found accompanying the colicky pains of gallstones or kidney stones; following spinal cord injury, pneumonia, or other generalized conditions; or being caused by peritoneal contamination by pus (from a perforated appendix) or acid (from a perforated ulcer). Mechanical ileus is that due to adhesions, ischemia, tumor, or stone and requires prompt decompression of the bowel to prevent perforation.
Symptoms. The principal symptoms of ileus are abdominal pain and distention, constipation, and vomiting in which the vomitus may contain fecal material. If the intestinal obstruction is not relieved, the circulation in the wall of the intestine is impaired and the patient appears extremely ill with symptoms of shock and dehydration.
Treatment. Distention of the abdomen is relieved by decompression, which involves intubation with a long, balloon-tipped tube (e.g., miller-abbott tube) that extends to the site of the obstruction, and use of constant suction. Because of the disruption in absorption of fluids and nutrients from the intestinal tract, fluids, electrolytes, and glucose are given intravenously. Surgical intervention to remove the cause of ileus is usually necessary when the obstruction is complete or the bowel is likely to become gangrenous. The type of surgical procedure will depend on the condition of the bowel and the cause of the obstruction. In some cases ileostomy or colostomy, either temporary or permanent, may be necessary. In cases of paralytic ileus due to causes other than contamination by pus or acid, tube decompression may be sufficient, but even in these patients, surgery may be needed to protect the bowel from overdistention and perforation. See also intestinal obstruction for patient care.
adynamic ileus that caused by inhibition of bowel motility; see ileus.
dynamic ileus (hyperdynamic ileus) spastic ileus.
mechanical ileus that caused by a mechanical cause, such as hernia, adhesions, or volvulus; see ileus.
meconium ileus ileus in the newborn due to intestinal obstruction by thick meconium.
paralytic ileus adynamic ileus.
spastic ileus that due to persistent contracture of a bowel segment.
ileus subpar´ta ileus due to pressure of the gravid uterus on the pelvic colon.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


Mechanical, dynamic, or adynamic obstruction of the intestines; may be accompanied by severe colicky pain, abdominal distention, vomiting, absence of passage of stool, and often fever and dehydration.
[G. eileos, intestinal colic, from eilō, to roll up tight]
Farlex Partner Medical Dictionary © Farlex 2012


Intestinal obstruction causing colic, vomiting, and constipation.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


GI disease Impairment of the fecal flow of GI contents Clinical Sx reflect point of obstruction and type of ileus; paralytic ileus causes little pain and is first evident through abdominal distension and vomiting; post-operative paralytic ileus may manifest itself through ↑ nasogastric secretions or oliguria; mechanical ileus is associated with vomiting, abdominal colic, distension and constipation, which may be episodic with intermittent relief by production of voluminous, watery stools Management Stabilize, decompress, repair. See Meconium ileus, Paralytic ileus.
Ileus types
Adynamic Paralytic ileus, 2º to electrolyte derangements, mesenteric arterial vascular accidents, peritoneal irritation, surgery, trauma, paraneoplastic phenomena
• Obstructive Intraluminal tumors, intussusception, gallstones, bezoar, feces, foreign bodies
• Intrinsic lesions Atresia, stenosis, strictures due to neoplasms, inflammation, chemicals, vascular lesions
• Extrinsic lesions Adhesive bands from C-sections, previous surgery, hernias, neoplasia, abscesses, volvulus, hematomas 
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


Mechanical, dynamic, or adynamic obstruction of the intestines; may be accompanied by severe colicky pain, abdominal distention, vomiting, absence of passage of stool, and often fever and dehydration.
[L., fr. G. eileos, intestinal obstruction, fr. eileō, to roll up, + -os, noun suffix]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


Failure, usually temporary, of the process of PERISTALSIS by which the bowel contents are moved onwards. More correctly known as adynamic ileus, or sometimes paralytic ileus, the condition is caused by injury, severe infection, loss of blood, shock, or deficiency of potassium, calcium or magnesium. There is persistent vomiting and abdominal distention. Treatment is to keep the bowel as empty as possible by use of a suction tube and to deal with the original cause.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005


Mechanical, dynamic, or adynamic obstruction of the intestines; may be accompanied by severe colicky pain, abdominal distention, vomiting, and absence of passage of stool.
[L., fr. G. eileos, intestinal obstruction, fr. eileō, to roll up, + -os, noun suffix]
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
Acute, subacute, and chronic classification can also be performed according to the onset of gallstone ileus. The chronic type is referred to as Karewsky syndrome and is characterized by chronic repetitive pain attacks and asymptomatic periods, resulting from the passage of bile duct stones through the bowel (3).
Chewing Sugar-Free Gum Reduces Ileus After Cesarean Section in Nulliparous Women: A Randomized Clinical Trial.
Fourteen patients presented to the emergency department with ileus; phytobezoar was diagnosed via abdominal CT.
The reasons for the delayed ambulation in Group B were as follows: (1) to prevent the anastomotic portion from being compressed by parts of the small bowel falling into the pelvic cavity due to gravity, resulting in intestinal anastomotic ischemia and leakage and (2) to decrease the rate of occurrence of an adhesive ileus. The pelvic inflammatory response is most severe a few days following surgery due to rectal operative trauma.
Kurokawa, "Vincristine-induced paralytic ileus during induction therapy of treatment protocols for acute lymphoblastic leukemia in adult patients," International Journal of Clinical Pharmacology and Therapeutics, vol.
In our case, the initial diagnosis made was paralytic ileus and bowel perforation, yet the final diagnosis of Ogilvie's syndrome was reached only after laparotomy, when several areas of necrosis and perforation were seen.
This case illustrates a primary enterolith ileus that was initially thought to be a gallstone ileus.
Short-term postoperative outcomes including verbal rating pain scores at 4, 8, 12, 24, and 48 hours after PACU discharge, postoperative opiate consumption (in oral morphine equivalents (OME)), postoperative ileus (defined as requirement of NGT postoperatively, inability to tolerate general diet by postoperative day 5, or clinician's documentation of ileus in postoperative course), and length of stay (LOS; prolonged length of stay was defined as >3 days) were collected from the colorectal surgical database.
In the past, staff members at Palm Beach Atlantic felt budgets were mandates handed down to them, says Ileus. The new system allows users to help create the budget from the bottom up, and stay in the loop.
Bunlar; MI, mekonyum ileus esdegeri (MIE) sendromu, mekonyum peritoniti ve mekonyum tikac sendromu (MTS)'dur [5].
Other causes were colonic tumor 9%, volvulus 7%, paralytic ileus 4%, internal hernias 3% and intossusceptions 2%.