What is bowel obstruction?

A bowel obstruction is a blockage in the small or the large intestine. It is a potentially dangerous condition and has several causes.

Someone with a full obstruction will find passing a stool or gas difficult, if not impossible. A partial obstruction can cause diarrhea.

Obstructions cause a buildup of food, gastric acids, gas, and fluids. As these continue to build up, pressure grows.

This can result in a rupture, or split. Whatever was behind the blockage can enter the abdominal cavity and spread bacteria. This can be fatal.

In this article, we examine the symptoms and causes of a bowel obstruction. We also take a look at how doctors can treat this condition and what people can do to prevent it from occurring.

Symptoms

Bowel obstructions can be painful and distressing. Symptoms include:

• vomiting
• diarrhea
• bloating
• constipation
• cramping
• decreased appetite
• inability to pass stools or gas
• nausea
• severe pain
• swollen belly

Vomiting and diarrhea are early signs of bowel obstruction. Recognizing these symptoms means that a person can seek treatment before the condition progresses.

If a fever develops after some of these symptoms, speak to a doctor. It can be a sign of a split in the bowel.

Causes

There are many possible causes of bowel obstruction. The different causes are either mechanical or non-mechanical.

Mechanical obstructions are physical barriers that prevent or restrict the flow of matter through the bowels. These include:

• adhesion, or tissue that can develop after abdominal or pelvic surgery
• diverticulitis
• a foreign object, if swallowed
• gallstones, though this is a rarer cause of obstruction
• hernias
• impacted stools
• infection
• inflammatory bowel diseases (IBDs)
• intussusception, which is when a segment of the bowel pushes into the next segment, making it collapse
• meconium plug, which is the first stool that newborns pass
• tumors
• a twisted bowel

Some refer to non-mechanical obstructions as ileus, or paralytic ileus. These occur when something disrupts the working of the entire digestive system.

The large and small bowels move in coordinated contractions. If something interrupts this process, a non-mechanical obstruction can occur. If a doctor is able to detect and treat the cause, the bowel obstruction is usually a short-term issue.

Some long-term, or chronic, medical conditions may cause a non-mechanical obstruction, however.

Causes of non-mechanical bowel obstructions include:

• abdominal or pelvic surgery
• diabetes
• electrolyte imbalances
• hypothyroidism
• Hirschsprung's disease, a condition wherein nerve cells are missing from the end of the bowel
• infections
• some nerve and muscle disorders, such as Parkinson's disease
• opioid medication

Risk factors

Some conditions and events increase the risk of a bowel obstruction occurring. If a person's intestines have not developed properly, they will be more prone to blockages.

Other risk factors for developing a bowel obstruction include:

• cancer, especially in the abdomen
• Crohn's disease or other IBDs, which can thicken the walls of the intestines
• previous abdominal or pelvic surgery, which may increase the risk of adhesions
• radiation therapy

When to see a doctor

If severe abdominal pain develops, a person should contact their doctor immediately.

Bowel obstruction can have serious consequences. A person should seek medical advice if any of the symptoms listed above occur. It is especially important to see a doctor if any of these symptoms occur after surgery.

Diagnosis

Diagnosis tends to begin with a physical examination. An obstruction can cause a hard lump in the abdomen, which a doctor may be able to feel.

The doctor will also ask questions and look at a person's medical history.

A doctor can use a stethoscope to check a person's bowel activity. A lack of regular bowel sounds, or the sounds being unusually quiet, can suggest a bowel obstruction.

Depending on individual cases, a doctor may recommend further tests. These can include:

• blood tests to check levels of electrolytes, liver and kidney function, and blood counts
• endoscopy, in which a doctor uses a special camera to look inside the gut
• CT scan
• X-rays

Doctors may use administer a substance called contrast via an enema. Contrast allows doctors to view the bowels more clearly when carrying out imaging tests.

Source: Medical News Today