Ileus
Ileus
Definition
Ileus is a partial or complete non-mechanical blockage of the small and/or large intestine.
Description
There are two types of intestinal obstructions , mechanical and non-mechanical. Mechanical obstructions occur because the bowel is physically blocked and its contents cannot 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. By contrast, non-mechanical obstruction, called ileus, occurs because the rhythmic contractions that move material through the bowel (called peristalsis) stop.
Demographics
The total rate of bowel obstruction due both to mechanical and non-mechanical causes is one in 1,000 people. Meconium ileus accounts for 9–33 percent of bowel obstructions in newborns.
Causes and symptoms
Ileus is most often associated with an infection of the peritoneum (the membrane lining the abdomen) or other intra-abdominal infections such as appendicitis . 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.
Ileus can also be caused by kidney diseases, especially when potassium levels are decreased (a condition called hypokalemia). Narcotics and certain chemotherapy drugs, such as vinblastine (Velban, Velsar) and vincristine (Oncovin, Vincasar PES, Vincrex) can also cause ileus. Infants with cystic fibrosis are more likely to experience meconium ileus (obstruction of a dark green material in the intestine in newborns).
When the bowel stops functioning, the following symptoms occur:
- abdominal cramping
- abdominal distention (pain often increases as distention increases)
- nausea, vomiting , and/or diarrhea
- failure to pass gas or stool
When to call the doctor
A healthcare professional should be contacted if a child experiences persistent abdominal distention, is unable to have normal bowel movements, or exhibits other symptoms of ileus. Persistent abdominal pain and chronic or prolonged constipation are also reasons to call the doctor.
Diagnosis
When a doctor listens with a stethoscope to the abdomen of a child suffering from ileus, 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 may also be useful in diagnosing 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.
Treatment
Patients may be treated with supervised bed rest in a hospital and bowel rest, where nothing is taken by mouth, and patients are fed intravenously or through the use of a nasogastric tube, 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 or death (necrosis) of intestinal tissue, 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, homeopaths and practitioners of traditional Chinese medicine can recommend therapies that may help to reinstate peristalsis.
Nutritional concerns
Following abdominal surgery, uncomplicated cases of ileus can be managed by minimizing the amount of food the patient consumes, ensuring adequate fluid intake, and correcting any electrolyte disturbances such as low potassium.
Prognosis
The outcome varies depending on the cause of ileus. When ileus results from abdominal surgery, the condition is usually temporary and lasts approximately 24–72 hours. The prognosis is less certain in cases in which death of intestinal tissue occurs; surgery becomes necessary to remove the necrotic tissue. In children with cystic fibrosis in which meconium ileus becomes evident soon after birth, the prognosis is linked with the primary disease; the median age of survival for cystic fibrosis patients is 30 years. However, new interventions in the treatment of CF are increasing the age span of people with CF every year.
Prevention
Most cases of ileus are not preventable. Surgery to remove a tumor or other mechanical obstruction may help to prevent a recurrence.
Nutritional concerns
In cases in which electrolyte imbalance is the cause of ileus, it is important to treat the underlying cause of the imbalance, which in many cases is related to chronic vomiting and/or diarrhea, poor fluid and/or food intake, or abuse of laxatives and diuretics (such as in individuals with bulimia nervosa ).
Parental concerns
When their child is diagnosed with ileus, parents may be concerned about the necessity of surgery to correct the problem. Surgery, however, is considered only in medical emergencies and for patients for whom more conservative treatments have failed.
KEY TERMS
Bulimia nervosa —An eating disorder characterized by binge eating and inappropriate compensatory behavior, such as vomiting, misusing laxatives, or excessive exercise.
Computed tomography (CT) —An imaging technique in which cross-sectional x rays of the body are compiled to create a three-dimensional image of the body's internal structures; also called computed axial tomography.
Meconium —A greenish fecal material that forms the first bowel movement of an infant.
Peritoneum —The transparent membrane lining the abdominal and pelvic cavities (parietal peritoneum) and the membrane forming the outer layer of the stomach and interstines (visceral peritoneum). Between the visceral and parietal peritoneums is a potential space called the peritoneal cavity.
Resources
BOOKS
Turnage, Richard H., and Patricia C. Bergen. "Intestinal Obstruction." In Sleisenger & Fordtran's Gastrointestinal and Liver Disease, 7th ed. Edited by Mark Feldman et al. Philadelphia: Saunders, 2002.
Wyllie, Robert. "Ileus, Adhesions, Intussusception, and Closed-Loop Obstructions." In Nelson Textbook of Pediatrics, 17th ed. Edited by Richard E. Behrman, Robert M. Kleigman, and Hal B. Jenson. Philadelphia: Saunders, 2004.
PERIODICALS
Miedema, Brent W., and Joel O. Johnson. "Methods for Decreasing Postoperative Gut Dysmotility." The Lancet Oncology 4, no. 6 (June 2003): 365–72.
ORGANIZATIONS
American Gastroenterological Association. 4930 Del Ray Ave., Bethesda, MD 20814. Web site: <www.gastro.org>.
WEB SITES
Beers, Mark H. and Robert Berkow, eds. "Ileus." The Merck Manual of Diagnosis and Therapy, 2004. Available online at <www.merck.com/mrkshared/mmanual/section3/chapter25/25c.jsp> (accessed January 6, 2005).
Bernstein, Linda R. "Clinic and Cost Impact of Postoperative Ileus." Medscape, April 30, 2002. Available online at <www.medscape.com/viewarticle/429661_1> (accessed January 6, 2005).
Irish, Michael. "Surgical Aspects of Cystic Fibrosis and Meconium Ileus." eMedicine. October 17, 2003.
Available online at <www.emedicine.com/ped/topic2995.htm> (accessed January 6, 2005).
Tish Davidson, AM Stephanie Dionne Sherk
Ileus
Ileus
Definition
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.
Description
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
Diagnosis
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.
Treatment
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.
Prognosis
The outcome of ileus varies depending on its cause.
Prevention
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.
Resources
BOOKS
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.
PERIODICALS
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.
OTHER
"Bowel Paralysis." Trigan Oncology Associates Page. 〈http://www.trigan.com/ileus.htm〉.
"Intestinal Obstruction." HealthAnswers.com. 〈http://www.healthanswers.com/database/ami/converted/000260.html〉.