Intestinal Obstruction in Dogs

When a dog eats a toy or other non-food object, the indigestible material can become lodged in the gastrointestinal tract, creating an intestinal obstruction. This problem can happen as a result of tumors or physical abnormalities as well. Blockage of the intestines is dangerous, potentially resulting in an infection or rupture. Although some obstructions may pass on their own, many will require surgery.

What Is Intestinal Obstruction?

An intestinal obstruction happens when a dog has a complete or partial blockage of the intestines. These obstructions are a bit like clogged pipes; the blockage impairs digestion and intestinal motility, preventing the dog from passing food and waste through the gastrointestinal (GI) tract. Partial obstruction allows the dog to pass some stool and gas, but this constriction will eventually damage the intestines if not remedied.

A complete GI obstruction is an emergency that can swiftly lead to death if untreated. The longer the blockage remains, the more likely it will restrict blood flow and lead to necrosis (death) of intestinal tissues. Bacterial infections may develop, and the intestines can even perforate, causing the dog to bleed internally.

Symptoms of Intestinal Obstruction in Dogs

Signs of obstruction may vary depending on the cause. A dog with a partial obstruction may have subtle signs at first, giving the impression of a simple upset stomach. These symptoms may progress without treatment over the course of several days. A full obstruction will be very uncomfortable and rapidly present with more severe symptoms.

Each of the symptoms associated with intestinal obstruction involves gastrointestinal distress and the cascade of problems that occur when the GI tract is not functioning as it should. Initial vomiting, diarrhea, and appetite loss will precede a swollen abdomen due to fluid and fecal retention. A dog may become lethargic and depressed due to discomfort, and if the obstruction persists or worsens, dehydration and malnutrition will follow.

Causes of Intestinal Obstruction

The most common cause of canine intestinal obstruction is the ingestion of a foreign body. Some dogs will eat the most surprising things: toys, bones, corn cobs, and clothing (especially socks and underwear). Sharp objects can both block and perforate the lining of the GI tract, causing dangerous internal bleeding. Strings, rope, and similar items can cause a linear foreign body, an obstruction that can cause parts of the intestines to bunch up the way a drawstring cinches a hood or waistband. Many foreign bodies cannot be digested or dissolved completely by gastric acids. Contact your vet right away if you see your dog eat something that can cause blockage.

Intestinal blockages may occur for reasons other than foreign body ingestion, including:

• Tumors: A growth or mass inside the intestines can gradually decrease motility and eventually grow large enough to cause a blockage. A tumor in the abdomen may grow large enough to put pressure on the intestines, blocking them from the outside.
• Intussusception: This condition occurs when the intestines fold into themselves in a telescopic manner. Foreign bodies and tumors can lead to intussusception, but other potential causes include infections, intestinal parasites, and dietary changes. Intussusception may also occur as a complication after intestinal surgery.
• Pyloric stenosis: This narrowing of the passage from the stomach to the small intestine can lead to a GI obstruction. Pyloric stenosis may be caused by a congenital abnormality (birth defect) or may develop over time in older dogs for reasons unknown.

Diagnosing Canine Intestinal Obstruction

It's important to contact a veterinarian right away if you detect the signs of intestinal obstruction in your dog. Don't allow mild to moderate signs to continue for more than one to two days as it can lead to irreversible damage. A dog with severe signs should be taken to the nearest emergency veterinary office for immediate attention.

Your vet will examine your dog and discuss its history before recommending further testing. If a GI obstruction is suspected, then the next step is to perform x-rays of the abdomen to look for abnormalities. The dog must ingest a radiopaque substance that will appear on x-rays of soft tissue. This substance is typically barium, a white liquid that shows up bright white on film. A series of x-rays are taken at timed intervals to watch the movement of the contrast travel through the GI tract. This allows the veterinarian to visualize the flow of the GI tract and determine the location of the blockage.

Blood and urine tests may also be needed to assess blood cell counts and organ function. These tests help your veterinarian assess the dog's overall health and determine the best treatment to support recovery.

Treatment and Prognosis

Most GI obstructions must be removed to restore normal GI function. This is often done through an abdominal surgery called an exploratory laparotomy. The vet will open the abdomen, locate the blockage, and remove it. After this, the vet will examine the intestinal tissue to determine if permanent damage has occurred. If damage is present, the vet may need to remove part of the intestine. The intestine is then carefully sutured closed to allow healing and prevent leakage.

If the obstruction is in the upper part of the small intestine (upper duodenum), an endoscopy may be effective in removing the blockage. This is far less invasive than surgery and may allow the vet to pass through the pylorus (the sphincter between the stomach and small intestine) and reach the upper duodenum. With the dog under anesthesia, a mechanical tube with a small camera is passed through the mouth into the esophagus. Special tools can be passed through the scope to retrieve or sample the obstruction. If a foreign body is found, it may be possible for the vet to grasp it with a tool and pull it out with the endoscope.

Some intestinal blockages will pass on their own and will not require surgery or endoscopy. These dogs may still need supportive care to recover fully. Your vet will likely give your dog fluids for rehydration and medications to soothe the GI tract and prevent infection.

Prognosis for a Dog with Intestinal Obstruction

If the obstruction can be removed easily, and there is minimal damage to the intestines, a dog should recover quickly and regain full health. More severe blockages with complications or the presence of a tumor may carry different prognoses based on the individual situation.

How to Prevent Intestinal Obstruction

You can prevent foreign body ingestion by keeping dangerous objects away from your dog. Make sure toys are too large to swallow. If your dog likes to chew up toys and eat them, be sure to only allow your dog to have them under direct supervision. Keep your dog away from trash. Watch your dog closely when outdoors. Keep laundry in a closed container. If you know your dog likes to eat certain items, be sure to keep them out of reach.

Tumors and other intestinal conditions may not be preventable, but early detection can keep partial obstructions from becoming complete. It can also minimize the damage done to the intestines. Be sure to contact your vet soon after signs appear.

Visit the vet for a routine wellness checkup every year or more as recommended by your vet. There's a chance your vet will find a complication during the exam that you are not yet aware of.