What is Bowel Obstruction?

There are many ways to address a bowel obstruction: it is sometimes called paralytic illeus, intestinal obstruction or pseudo-volvolus. Bowel obstruction is a medical condition where a blockage prevents the normal flow of intestinal contents through the intestinal tract. It occurs mostly in the small intestine, probably because the small bowel has a tubular shape and is not as anchored as the large intestine, thus making it prone to unintentional kinking. The blockage can be partial or complete, but it can occur anywhere distal to the duodenum.

Bowel obstruction is a medical emergency that requires immediate clinical attention, and depending on the extent and severity of the obstruction, might require surgery. It's an emergency because the increasing intra-intestinal pressure can rupture the tract causing contamination of the peritoneal cavity with intestinal contents, potentially leading to peritonitis with internal bleeding. Tissue death may occur as a result from twisting of the bowel and strangulation of its circulation.

Bowel obstruction is relatively common and is responsible for a large number of hospitalizations, constituting about 15% of all emergencies related to abdominal pain. Prior abdominal surgery is the most common cause of bowel obstruction. This condition is frequently observed as a complication of advanced cancer with an incidence of about 3% in these patients. Advanced ovarian cancer patients have a particularly high risk of bowel obstruction in the order of 25-­45%.

What Causes Bowel Obstruction?

Intestinal obstruction is not classified as a disease itself, but occurs as a complication of intestinal surgery or from certain diseases such as cancer or Chron's disease. In infants, bowel obstruction may be caused by chemical disturbances, abdominal surgery, decrease in blood supply to the abdominal area, or the use of certain medications used to treat a medical condition. In children, most cases are due to viral or bacterial infection, simply food poisoning (gastroenteritis), or may be associated with appendicitis or peritonitis.

The obstruction can be of mechanical or functional nature. In mechanical obstructions, the pressure from the intestinal walls causes intraluminal or intramural blockage. Examples are sliding of the intestine walls or the telescoping of the bowel into another segment of the intestines, tumors and abscesses that block the passageway, polyps and stenosis in the bowel. A hernia can also cause bowel obstruction when it leads to narrowing of the intestinal lumen. Adhesion of intestinal walls is a common complication from intestinal surgery which leads to bowel obstruction. As an example, resection of the appendix (appendectomy) is a common bowel surgery that is associated with a 3% rate of bowel obstruction. In functional obstruction (also called pseudo-obstruction), the intestinal musculature is incapable of propelling the contents along the bowel. This condition can be caused by neurologic disorders such as Alzheimer's, Parkinson's, and strokes that affect the part of the brain that controls digestion. Hormonal disorders such as diabetes and Adrenal Hyperactivity can affect the intestinal muscles and halt regular autonomous movement of the intestinal muscles (peristalsis). Muscular dystrophy and Guillain-Barre syndrome can also affect the intestinal muscles.

Symptoms of Bowel Obstruction

The symptoms of bowel obstruction depend on whether it occurred on the small or large intestine. These can help with the diagnosis because symptoms also differ depending on the level of obstruction.

In a small bowel obstruction:

  • Initial symptom is cramping pain described as wave-like and colicky, located in the peri-umbilical region of the abdomen.
  • Unable to pass gas.
  • Bloating with gurgling sounds from the abdomen.
  • Vomiting, sometimes with blood and mucus. Upper small intestinal obstruction is indicated by green colored vomit.
  • Enlargement of the abdomen.
  • Signs of dehydration, such as dry mouth, intense thirst, drowsiness and shock (late sign) – at this point, patients need immediate emergency medical treatment.

In a large bowel obstruction:

  • Abdominal Pain: Pain is located in the hypogastric area of the abdomen.
  • Bloating
  • Vomiting is not common. If the obstruction is in the large bowel, the patient first vomits the stomach's contents, then bile-stained vomitus and then darker more fecal-like contents from the large intestine.
  • Bad breath is common in the later stage.

In both types of obstruction, constipation or diarrhea (in partial obstruction) might be observed.

Diagnosis of Bowel Obstruction

Doctors base their initial findings on a person's complaints and physical examination, including their bowel sounds. An unusually high-pitched bowel sound is heard when listening to the abdomen if the early stage of obstruction is present, as the intestine is working hard in attempting to recover from the obstruction. Later on, if strangulation develops, an absent or low-pitched bowel sound may be heard. However, the diagnostic value of intestinal sounds are debated and further tests are required to confirm diagnosis.

The diagnosis based on the symptoms are initially confirmed by abdominal X-rays. The radiograph often presents bowel enlargement and presence of multiple gas levels on different areas. The doctor may order further tests such as Computerized Tomography (CT) scanning with barium-contrast swallowed or given as an enema to the patient. The barium is a substance that increases the contrast in X-rays, and is used to more clearly define the obstruction. In cases of tumors and polyps, endoscopy is done to define the affected areas. This intervention is performed by the insertion of a tube with a camera in the esophagus. The tube can also be attached with lasers or forceps to gather tissue for biopsy. An alternative is to perform colonoscopy, a procedure similar to endoscopy, but in which the tube is inserted into the rectum. The decision of which test is to be used depends on the suspected location of the blockage. After gathering a tissue sample, biopsy is done to assess whether the tumor is benign or malignant. Barium enema used as a diagnostic tool could also serve as a treatment in some cases, as it loosens that part of the intestine with blockage when inserted inside the abdomen. If the diagnosis is inconclusive, a laparotomy could provide a definite diagnosis and potentially correct a strangulated obstruction.

Blood tests may reveal dehydration and infection. A high white blood cell count means rupture with infection, and high hematocrit signifies dehydration and lost blood plasma.

Treatment of Bowel Obstruction

Treatment may vary depending if the obstruction is partial or complete, simple or strangulated. If the doctor has determined the nature and location of the obstruction, the first treatment is usually conservative because the obstruction may resolve by itself. Treatment for either partial or complete obstruction, usually starts with IV drops and different medications, including antibiotics to relieve symptoms and potentially resolve the obstruction. If initial treatment fails, nasogastric suction is commonly performed. Anti-emetics are not recommended, instead restrict food and water. The patient is monitored and periodic X-rays are done to ensure that the condition is not getting worse.

Strangulated bowel obstruction is considered a medical emergency, so patients must be hospitalized in order to receive adequate treatment. Immediate decompression is the initial goal as delayed treatment is fatal; contents of the intestines are removed via lavage. Some may resolve spontaneously, but many need immediate surgery especially if there is complete obstruction, rupture and infection. Before the surgery, the patient is given fluids intravenously to replace the lost electrolytes combined with antibiotics when an infection is suspected. The surgeon can relieve the cause by repairing a hernia, remove the blocked bowel, connect the remaining parts and dividing the adhesions. The surgeon may remove the intestine if its circulation is compromised and resects the remaining parts. In cases where the obstruction is caused by a malignant cancer, care is taken not to spread the tumor through surgery, and the patient will undergo chemotherapy for treatment or palliation. If the obstruction is found on the large intestine, permanent or temporary resection of the colon (colostomy) is necessary.

Ileostomy could also be performed. On those cases where partial obstruction is present, and surgical treatment is not necessary, symptoms should be medically managed. If constipation is present, education is important for supporting lifestyle modification. Exercise and high-fiber diets are always beneficial. Magnesium containing compounds could also be taken as help. Suppositories could also help to loosen the bowel, but laxatives and enemas are being cautioned, for abuse of these products could impede the normal movements of the stomach.

If the obstruction is on the late stage, medical emergency is instituted. It is very important to always note the patient's vital signs and be alert for an indication of shock, like low blood pressure (hypotension), accelerated heart beat (tachycardia), and rapid breathing (tachypnea). It is also important to monitor the patient's vomit including its color, odor, amount and consistency.

Prognosis of Bowel Obstruction

The prognosis is usually excellent, especially if the condition is recognized earlier. Many resolve spontaneously and the cause can be removed surgically. If there is a cancer, the part with the tumor is resected and the patient will undergo chemotherapy to prevent its spread. The prognosis is better if the intestine did not rupture, or dehydration did not develop. Problems usually arise if the patient is severely dehydrated, if the condition involves death of intestinal tissue due to strangulation, or if the spread of cancer and massive infection can occur after the distended intestine ruptures.

Preventing Bowel Obstruction

Bowel obstruction can happen to anyone, and there is no known genetic tendency that directly leads to the development of this condition. However, people with tendencies to develop certain cancers are at higher risk of bowel obstruction. A diet high in complex carbohydrates and fiber can maintain a healthy digestion and reduce risks of polyps. If you had a relative with colon cancer, perhaps living on a diet free of carcinogens can help. Avoid processed and barbecued meats, reduce alcohol intake and take lots of colorful fruits and vegetables. For people with hernia, try pelvic exercises regularly to strengthen pelvic muscles and consult your doctor for immediate treatment.

Living with Bowel Obstruction

In cases of partial obstruction, care should be taken not to block the already small opening of the intestine. Meals should be small and frequent, foods should be served in small pieces and easily digested, and plenty of fluid should be administered. Improvement is monitored and worsening signs are reported immediately to the doctor for treatment.

When a colostomy is performed, the patient might experience feelings of loss and disfigurement, and a change in lifestyle is necessary. The family and close friends should be informed about the procedure and help the patient to understand and cope with the situation. After colostomy, the intestinal waste will be collected in an appliance outside of the body. The so-called ostomy appliance itself may be a hindrance to performing a job or activities of daily living.

For people with malignant tumors of the bowel, the condition requires profound changes and can be a source of great anxiety. It is emotionally disturbing, and it may hamper treatment. Providing facts and right information can be helpful, encourage verbalization of fears and expectations. The important thing is emotional awareness and support. The patient should be accepted by his or her family, usual activities should be resumed if possible, or alternatives should be found.

Having a hobby that does not require movement on the abdomen such as computers, reading and teaching are helpful and may persist as careers to replace any lost income and gain back one's self confidence. Search for ways to manage and work even with a colostomy appliance attached, join a group or association for people with colostomies. Be a friend to someone who has a colostomy as well, and help other people who have problems with their colostomies.

Current Research of Bowel Obstruction

Ongoing research involves the development of algorithms for early and accurate diagnosis of bowel obstruction. They aim to quickly locate the location of the obstruction and early treatment.

The use of corticosteroids is being investigated for use in adhesions. Patients should be careful with this medication as it may aggravate the condition and can only be taken with medical prescription.

Fat cell cancer (lipoma) on the abdominal wall might cause intestinal obstruction, especially to people with Proteus Syndrome. Aggressive treatment often causes severe functional and cosmetic consequences, and surgery is not done until it is absolutely necessary. Research for an alternative treatment is being developed.

Myopathies and celiac disease often result in bowel obstruction, and research is ongoing to alleviate its manifestations in the bowel.

Octreotide is being researched for use as an analgesic for chronic pain due to malignant bowel obstruction. It has produced positive results in providing comfort to patients suffering from bowel obstruction. It is especially good in relieving a patient's nausea and vomiting, symptoms that are often associated with this condition.

Last Updated: Tuesday, February 7, 2012