Brief overview
- Symptoms: Usually severe abdominal pain, nausea and vomiting, distended abdomen, possibly fever, poor general condition.
- Course of disease and prognosis: Intestinal obstruction is a life-threatening emergency! The earlier it is treated, the better the chances of survival.
- Treatment: Shock therapy, fluid supply via venous drip, emptying of the intestine via gastric or small intestinal tube, medication (painkillers, anti-nausea and anti-vomiting agents, antibiotics, etc.); if necessary, surgical removal of the obstruction, artificial anus.
- Causes and risk factors: mechanical obstructions such as tumors, scarring, intestinal entrapment in case of inguinal hernia, paralysis or cramping of the intestinal wall
- Examination and diagnosis: patient interview (history), physical examination, imaging procedures (X-ray, ultrasound, computed tomography if necessary)
- Prevention:There is no known general prevention. Measures to support regular digestion are advisable.
Intestinal obstruction (ileus) is described as an interruption of the passage through the small or large intestine. The preliminary stage of ileus is called subileus. It is a clinically not yet fully developed intestinal obstruction.
If the intestine is no longer able to pass its contents as usual, bacteria proliferate there. If they enter the bloodstream, there is a risk of blood poisoning (sepsis). Due to the accumulation of food residues and the formation of gas, the intestine expands considerably. Its wall becomes thin and susceptible to ruptures and holes.
There is a risk of leakage of intestinal contents and peritonitis.
At the same time, in an ileus, the intestine no longer absorbs blood salts (electrolytes) and fluids that are important for the body into the bloodstream. This increases the risk of circulatory shock.
What are the symptoms of intestinal obstruction?
Mechanical ileus: symptoms
Bowel obstruction symptoms in the mechanical type are:
- Violent, cramping (colicky) abdominal pain that increases and decreases in waves
- Acute wind and stool retention
- Nausea and vomiting
- Bloated abdomen
- Increased intestinal wind (flatulence)
- Belching
- Accelerated heartbeat
- Fever
In strangulated ileus (i.e., due to intestinal impaction or strangulation), the affected section of the intestine is no longer supplied with blood. The pain is then permanent. In addition, blood pressure drops, the pulse accelerates and affected persons vomit heavily – in extreme cases even feces (vomiting of feces).
Paralytic intestinal obstruction: symptoms
Intestinal obstruction symptoms in the paralytic (paralyzed) type are less severe and delayed in onset. It is true that patients also suffer from signs such as nausea and vomiting in this form of bowel obstruction. However, because the bowel is paralyzed, no bowel sounds are heard. Doctors then also speak of “grave or dead silence”.
As a symptom of paralytic ileus, affected individuals sometimes vomit intestinal contents as it progresses.
Location of the ileus influences symptoms
Symptoms differ depending on which part of the intestine the intestinal obstruction occurs. The higher it sits in the intestine (such as in the small intestine), the earlier and more severely the affected person vomits. Often, with a high intestinal obstruction, bowel movements are still possible at first.
In the case of a deep bowel obstruction, the symptoms begin more gradually with loss of appetite, a feeling of fullness, nausea and increasing abdominal girth.
As it progresses, vomiting also occurs.
Intestinal obstruction or constipation?
Sometimes the symptoms of persistent constipation resemble those of intestinal obstruction, such as colicky abdominal pain or a distended abdomen. During the examination, a doctor clarifies what the problem is and initiates the right treatment for the particular case.
What is the life expectancy with an intestinal obstruction?
The earlier an intestinal obstruction is detected, the better it can be treated. Without treatment, ileus is life-threatening. Life-threatening complications of intestinal obstruction include such things as:
- Breakthrough of the intestinal wall (perforation).
- Bacterial toxin enters the bloodstream via the intestine (blood poisoning = sepsis)
- Circulatory or multi-organ failure as a result of sepsis
- Shock due to fluid and electrolyte deficiency
Because the food pulp remains in the intestine, the pressure on the intestinal wall increases dangerously. The sensitive mucosa is injured (mucosal erosions). There is a risk that parts of the intestinal wall will die (intestinal wall necrosis). Bacteria then migrate through it and cause peritonitis.
The mortality rate for intestinal obstruction is five to 25 percent. Every hour that passes without treatment increases the risk of death by about one percent.
How is intestinal obstruction treated?
Treatment depends on what caused the bowel obstruction and in which section of the bowel it occurs. Conservative measures are often sufficient. In any case, the patient must refrain from eating and drinking for the time being. Usually, he or she is given a stomach or small intestine tube to drain the backlogged intestinal contents.
Patients also receive an infusion (venous drip) to quickly supply the body with nutrients and fluids. Drugs (e.g., for nausea and vomiting) can also be administered directly into the bloodstream. To control urine output, the doctor sometimes places a bladder catheter.
Other conservative measures that may be useful in the treatment of intestinal obstruction include enemas, warm and moist abdominal compresses and the administration of medications to stimulate intestinal peristalsis.
After the operation, the patient receives an infusion for several days. Only after the first bowel movement does one slowly begin to get the bowel moving – first with tea, then with liquid and later with strained food. Finally, after about ten days, easily digestible food in the form of rusks, bananas or potatoes is allowed.
What are the causes of intestinal obstruction?
There are various causes of intestinal obstruction. In principle, the following main groups of an ileus are distinguished:
- Mechanical intestinal obstruction: Most common form of bowel obstruction due to a mechanical obstruction, e.g., tumors, adhesions or adhesions, foreign bodies, or entrapment of the bowel
- Functional bowel obstruction: bowel obstruction due to a disorder of the bowel muscles. This primarily includes paralytic ileus (cause: paralysis of the intestinal muscles). Rarely, spastic ileus (cause: spasm of the intestinal muscles) occurs.
Mechanical ileus
A mechanical intestinal obstruction is caused, for example, by strangulation of the blood vessels supplying the intestine (strangulated ileus). This happens, for example, in the case of an inguinal hernia when a piece of intestine is trapped in the hernial orifice (incarceration). However, a strangulation ileus also results when the intestine rotates on its own axis (volvulus) or when a piece of intestine overlaps the following intestinal segment (intussusception).
In other cases, mechanical intestinal obstruction results from obstruction of the intestinal lumen, for example, by a foreign body, worms, or a tumor (such as colon cancer). Hard fecal stones also sometimes obstruct the intestine (more precisely: colon).
Sometimes mechanical bowel obstruction is due to a narrowing of the bowel lumen from the outside. One possible cause is adhesions in the abdominal cavity as a result of inflammation or surgery. Such adhesions are called “briden”, which is why this is also referred to as bridenileus.
Tumors in the abdominal cavity also sometimes press on the intestine in such a way that intestinal passage is obstructed or interrupted. This happens, for example, in some cases of extensive cancer of the peritoneum (peritoneal carcinomatosis).
Often, ringing bowel sounds, also called peristalsis, are heard when the bowel is pressed hard from the outside. The sounds occur when the food pulp is forced with pressure through the constriction in the intestine.
Pathological processes in the intestinal wall, such as in chronic inflammatory bowel diseases (Crohn’s disease, ulcerative colitis) or inflamed intestinal protrusions (diverticulitis) are also possible causes of mechanical bowel obstruction.
In contrast to mechanical intestinal obstruction, in paralytic ileus it is not an obstruction that blocks the onward transport of the food pulp, but a paralysis of the intestinal muscles.
This paralysis is the result, for example, of vascular occlusion, such as blood clots (thrombi). In this case, experts speak of primary paralytic ileus.
More common is secondary paralytic ileus: In this case, the intestinal muscles are paralyzed by mechanical stimuli, for example, due to surgery or severe abdominal diseases (such as peritonitis or appendicitis).
You can learn more about the causes, signs and treatment of intestinal obstruction due to paralysis of the intestinal wall in the article Paralytic ileus.
Spastic ileus
Intestinal obstruction in the elderly
The elderly are more likely to suffer from chronic constipation, so they are sometimes at risk of bowel obstruction. The risk is higher for seniors because they more often suffer from diseases (such as diabetes mellitus) or take medications (such as certain painkillers) that promote constipation and ileus.
Often, elderly people drink insufficient amounts of fluids, exercise less, and their digestion is slower. It is therefore particularly important that the elderly themselves – or, in the case of those in need of care, their relatives and caregivers – keep an eye on their regular digestion.
In the case of chronic constipation, some people turn to laxatives. However, certain laxatives deprive the body of fluids and lead to habituation in the long term – in the longer term, there is a risk that constipation will worsen. It is therefore advisable to take laxatives only in consultation with a doctor.
Intestinal obstruction in infants
Intestinal obstruction sometimes occurs in babies as well. One reason, for example, is that a section of the intestine is blocked from birth (intestinal atresia). Another possible cause is that the newborn’s first, tough stool (meconium) blocks the intestine. Doctors refer to this as meconium ileus.
The meconium consists of hair, skin and mucous membrane cells swallowed in utero, among other things.
Meconium ileus is usually an early indication of a congenital metabolic disease, cystic fibrosis.
Intestinal obstruction: examinations and diagnosis
If intestinal obstruction is suspected, the physician will ask the patient in detail about his or her medical history (anamnesis): Among other things, he asks how long the symptoms have existed, where exactly the pain occurs, when the stool and bowel movements last occurred, and whether the patient has undergone abdominal surgery.
If bowel sounds are heard, this is more likely to indicate mechanical bowel obstruction. In the absence of bowel sounds (“grave/dead silence in the abdomen”), on the other hand, it is probably a case of paralytic ileus.
A physical examination in the case of intestinal obstruction also involves the physician palpating the rectum with a finger via the anus (rectal examination).
An ileus can be visualized with the aid of an X-ray examination. As early as four to five hours after the onset of ileus, the X-ray images show distended intestinal loops containing fluid.
If a large bowel obstruction is suspected, the patient is often given an enema with a contrast medium before the X-ray. The images show exactly where the obstruction is located.
In certain cases, a computed tomography (CT) scan is useful, for example if tumors are suspected or in preparation for surgical treatment.
Intestinal obstruction: prevention
Intestinal obstruction or its various causes cannot generally be prevented. However, some measures are helpful for regular bowel movements. These include a high-fiber diet with plenty of fruits, vegetables and whole grains. Fiber stimulates bowel activity.
Sufficient fluid intake (1.5 to 2 liters per day) and regular exercise are also important for regular digestion.
After abdominal surgery, adhesions sometimes form in the abdominal cavity, which can sometimes trigger an ileus. After abdominal surgery, it is therefore advisable to watch out for possible signs of intestinal obstruction (abdominal pain, failure to have a bowel movement, etc.) and, if necessary, see a doctor at an early stage.