Intestinal Obstruction

Intestinal obstruction is a serious medical condition where food, liquid, gas, or stool cannot pass through the small or large intestine normally. This blockage requires immediate medical attention to prevent dangerous complications.

Table of contents

• What Is Intestinal Obstruction?
• Signs and Symptoms
• Common Causes
• When to Seek Emergency Care
• How Doctors Diagnose the Condition
• Treatment Options
• Possible Complications
• Preventing Future Obstructions

What Is Intestinal Obstruction?

Intestinal obstruction is a blockage that prevents food, liquid, gas, or stool from moving normally through your digestive system. This blockage can occur in either the small intestine or the large intestine, which is also called the colon^[1]. Your intestines are responsible for moving food and waste from your stomach to your rectum, where you pass it as stool. When an obstruction occurs, this normal flow stops or slows down significantly^[2].

The obstruction can be partial or complete. A partial obstruction means the intestine is narrowed but some material can still pass through. A complete obstruction means nothing can pass through, not even gas^[2]. Most intestinal obstructions—approximately 80%—occur in the small intestine, while about 20% affect the large intestine^[2].

Intestinal obstruction is a common reason people visit the emergency department. Without treatment, the blocked parts of the intestine can die, leading to serious problems. However, with prompt medical care, intestinal obstruction can often be successfully treated^[1].

• Small intestine
• Large intestine (colon)
• Stomach
• Rectum

Signs and Symptoms

The symptoms of intestinal obstruction can vary depending on which part of the intestine is blocked and whether the blockage is partial or complete. However, there are several common signs that indicate a possible obstruction^[1].

If the blockage is in the small intestine, you may experience sharp stomach pains that come in waves. These pains tend to be cramping and intermittent, lasting a few minutes at a time. The pain is usually located in the center and middle part of your abdomen. Eventually, the pain may become constant^[2][3].

Common symptoms include:

• Crampy abdominal pain that comes and goes
• Abdominal swelling or bloating
• Nausea and vomiting
• Loss of appetite
• Inability to pass gas or have a bowel movement
• Constipation
• Diarrhea (usually a sign of partial blockage)
• Signs of dehydration such as rapid heartbeat and dark-colored urine^[1][2]

In cases of complete obstruction, you will not be able to pass gas or stool at all. With a partial blockage, symptoms may come and go, and you might still pass some stool or gas^[6].

Children and infants can also experience intestinal obstruction. Infants cannot tell you where it hurts, but they may pull their legs up toward their bellies and cry. Other symptoms in children include fever, blood in stool, green or yellow-green vomit, lethargy, and a swollen, firm belly^[2].

Common Causes

Intestinal obstruction can result from mechanical causes, where something physically blocks the intestine, or from functional causes, where the intestine stops working properly even though there is no physical blockage^[3].

The most common cause of small bowel obstruction is adhesions—bands of scar-like tissue that form in the abdomen after surgery. These adhesions can cause loops of the intestine to stick together or to other organs, creating a blockage^[1][4].

Other common mechanical causes include:

• Hernias—when part of the intestine pushes through a weak spot in the abdominal wall
• Tumors—particularly colon cancer or other cancers that block the intestinal passage
• Volvulus—when the intestine twists on itself
• Intussusception—when one part of the intestine telescopes into another part
• Inflammatory bowel disease—conditions like Crohn’s disease that can cause narrowing or strictures
• Impacted stool or severe constipation
• Diverticulitis—inflammation of small pouches in the colon wall^[1][3]

Large bowel obstructions are most often caused by tumors and volvulus. About 40% of people with colon cancer are diagnosed because bowel obstruction symptoms from the tumor prompted them to seek emergency care^[2].

Functional obstructions, also called paralytic ileus or pseudo-obstruction, occur when the intestine stops working properly but there is no physical blockage. This can happen after abdominal surgery, due to infections, from certain medications (especially narcotics), or from chemical and electrolyte imbalances in the body^[13].

When to Seek Emergency Care

Intestinal obstruction is a medical emergency that requires immediate care. With a bowel obstruction, time is critical. If you notice symptoms of an obstruction, you should call a healthcare provider or go to an emergency department right away^[2].

You should seek immediate medical attention if you experience:

• Severe abdominal pain or other symptoms of intestinal obstruction
• Inability to pass gas or have bowel movements
• Persistent vomiting
• Abdominal swelling that does not go away
• Unexplained abdominal pain that does not go away^[1][13]

If you had recent abdominal surgery and develop these symptoms, contact your doctor immediately. Some types of bowel obstruction can lead to very serious complications and even death if not treated promptly^[6].

How Doctors Diagnose the Condition

When you arrive at the hospital with suspected intestinal obstruction, doctors will first examine you and ask about your medical history, including any previous surgeries. During the physical exam, your doctor may check if your abdomen is swollen or tender, feel for any lumps, and listen for bowel sounds with a stethoscope^[8].

To confirm the diagnosis, doctors typically order imaging tests. An X-ray of the abdomen is often the first test performed. X-rays can show signs of blockage, such as dilated loops of intestine filled with air and fluid. However, some intestinal obstructions cannot be seen clearly on standard X-rays^[8][12].

A computed tomography (CT) scan is more accurate than X-rays and is recommended if the suspicion of obstruction is high or if X-rays are unclear. CT scans can reliably determine the cause of the obstruction, identify the exact location where the blockage occurs (called the transition point), and detect serious complications such as reduced blood flow to the intestine or perforation^[3][12].

For children or pregnant women, doctors may use ultrasound or MRI scans instead of CT to avoid radiation exposure. Ultrasound can be particularly helpful in diagnosing intussusception in children^[3][8].

In some cases, doctors may use other tests such as a barium enema or water-soluble contrast studies. These involve giving you a special liquid to drink or inserting it through your rectum, which helps make the blockage more visible on X-rays. These contrast studies can serve both diagnostic and therapeutic purposes^[8][12].

Treatment Options

Treatment for intestinal obstruction depends on the location and severity of the blockage, as well as what is causing it. In almost all cases, you will need to be hospitalized^[8].

Initial treatment focuses on stabilizing your condition. You will receive intravenous (IV) fluids to correct dehydration and restore electrolyte balance. To relieve pressure and symptoms, doctors will insert a nasogastric (NG) tube through your nose into your stomach. This tube removes gas and fluids from your digestive tract, helping to decompress the intestines and relieve pain and pressure. You will not be given anything to eat or drink while the obstruction is being treated^[7][8].

Doctors may also prescribe antibiotics to protect against bacterial infection, pain medications as needed, and sometimes medicines to help increase contractions in your intestines^[10][14].

Many partial obstructions get better on their own with this conservative treatment. About 65-81% of partial small bowel obstructions without complications resolve without surgery. Most people improve within 72 hours of starting this treatment^[12][14].

However, surgery is needed in certain situations:

• Complete blockages that do not resolve with conservative treatment
• Signs of strangulation—when the blood supply to the intestine is cut off
• Evidence of tissue death or perforation (a hole in the intestine)
• Obstructions that do not resolve within 48-72 hours of conservative treatment
• Symptoms that worsen despite treatment^[12][14]

Surgery aims to remove the blockage and repair any damage to the intestinal tissue. In some cases, surgeons may need to remove damaged portions of the intestine. You may need a colostomy or ileostomy after surgery—a procedure where the healthy part of the intestine is connected to an opening in your abdominal wall, and stool passes into a bag. Sometimes this is temporary until you recover, and the intestine can be reconnected later^[10].

For some types of obstructions caused by tumors or inflammation, doctors may use other approaches such as placing small mesh tubes called stents to open up the blockage, or using air or liquid enemas for certain conditions like intussusception^[8][10].

Possible Complications

Without prompt treatment, intestinal obstruction can lead to serious and potentially life-threatening complications^[1].

When the intestine is blocked, waste, gas, and digestive juices build up behind the blockage, causing the intestine to swell. This increased pressure can damage the tissue and compromise blood flow to the affected area. If blood supply is cut off, the intestinal tissue can die—a condition called bowel ischemia or gangrene^[2][7].

Other serious complications include:

• Perforation—a hole develops in the intestinal wall, allowing bacteria and intestinal contents to leak into the abdominal cavity
• Peritonitis—a life-threatening infection of the abdominal cavity
• Sepsis—a widespread infection that enters the bloodstream
• Severe dehydration and electrolyte imbalances
• Respiratory problems from pressure on the diaphragm by a distended abdomen
• Aspiration of vomit into the lungs^[3][13]

The risk of these complications is higher with certain causes of obstruction. Hernias, volvulus, and intussusception carry a higher risk of tissue death because they are more likely to cut off blood supply^[13].

These serious complications are why intestinal obstruction is considered a medical emergency requiring immediate attention. Early diagnosis and treatment significantly reduce the risk of complications^[6].

Preventing Future Obstructions

While not all intestinal obstructions can be prevented, there are steps you can take to reduce your risk, especially if you have had an obstruction before^[16].

If you have a history of bowel obstructions, doctors may recommend dietary changes. Eating smaller meals more frequently throughout the day can help. Chew your food very well—try to chew each bite until it becomes liquid. Some doctors recommend avoiding high-fiber foods and raw fruits and vegetables, as these may increase the risk of another blockage^[16].

Drinking plenty of water may help prevent obstructions. However, if you have kidney, heart, or liver disease and need to limit fluids, talk with your doctor before increasing your fluid intake. You should check with your doctor before eating whole grain products or using fiber supplements^[16].

Some doctors may recommend medications such as stool softeners or mild laxatives to help keep things moving through your intestines. For people with a history of adhesion-related obstructions, a low-residue diet (which limits high-fiber foods) and medications like MiraLAX can help make material flow more easily through the bowel^[17][20].

Staying physically active can also help. Try to get at least 2½ hours of moderate physical activity each week. Walking is a good choice that most people can do^[16].

Treating underlying conditions that can lead to obstruction is important. This includes managing inflammatory bowel disease, treating hernias before they cause problems, and following up with cancer screening recommendations^[13].

It is common for people to experience repeat bowel obstructions, especially if they have conditions like Crohn’s disease or extensive abdominal scar tissue. If you have had an obstruction before, work closely with your healthcare team to develop a prevention plan tailored to your specific situation^[17][19].