Downeast Dog News

Foreign Bodies

By April Guille, DVM, DACVS - Portland Veterinary Specialists | Aug 01, 2018

Unfortunately, most people know a pet that has eaten something it shouldn't have. These objects, termed "foreign bodies" by the veterinary medical world, can wreak havoc in a pet's gastrointestinal tract. While some objects are small enough they can pass through with little to no damage, larger objects, objects with sharp edges, and linear objects (such as threads or ribbons) can cause life threatening problems for our pets.

Food normally passes through the esophagus into the stomach. After partial digestion, the food will move into the small intestine for further digestion and absorption. The colon, or large intestine, allows for reabsorption of water and is the last step before stool exits via the rectum. In addition to food, fluids in the form of water, saliva, stomach acid, bile, and pancreatic digestive enzymes move through the gastrointestinal tract. All parts of the GI tract move to assist in the passage of food. Foreign material becomes an issue when it blocks or partially blocks the passage of food and fluids in the gastrointestinal tract or causes a hole in the GI tract, allowing the leakage of contents and bacteria into the abdominal cavity.

The most common signs owners will see are vomiting, lethargy, and lack of an appetite. Vomiting can range from mild to severe, depending on the location of the obstruction. Blockage effectively stops the forward movement of the intestinal contents, causing dilation, spasms, pain, and eventually the complete cessation of movement in the GI tract. Partial obstructions can be tricky to diagnose because the vomiting may be intermittent, and some food gets by the obstruction. These pets will often lose a significant amount of weight as time progresses.

While many of the foreign body offenders are dogs, cats can also get into mischief and especially like to go after string. Objects like this are termed linear foreign bodies and cause an issue when one end becomes fixed in place, either because they are too long or they become stuck on something. The intestines continue to move and bunch up on the string, much like an elastic in a hair scrunchie. As the intestines move back and forth, they cut themselves on the string and multiple holes form in the intestines. Any perforation in the GI tract will lead to septic peritonitis from the leakage of fluid and bacteria. A perforation is a surgical emergency and will result in death without prompt treatment.

Many foreign bodies are not visible on radiographs (X-rays) but a pattern can be seen in the intestines that raise suspicion for an obstruction. Ultrasound can be very helpful in seeing a foreign body and the obstruction it causes, but ultrasound is not foolproof. However, as the saying goes, it is better to have a negative surgical exploratory (in which case we can take surgical biopsies and look at all the organs for the source of the vomiting) than a positive necropsy, meaning a foreign body is found after the pet has died from complications.

If the foreign body cannot pass on its own and is located in the stomach, endoscopy may allow for its removal without surgery. An endoscope has a small camera on the long end of a flexible tube. Small tools, such as graspers or a small net, can be passed through the endoscope and trap the foreign body, allowing its removal. If an object is too slippery, heavy, or dangerous to remove back up the esophagus, or if it is already entering into the small intestine, surgery is the next step. Some objects can stay in the stomach for months. Corn cobs are a common offender. Dogs should never be allowed to chew on corn cobs. While highly appetizing, they eventually break down into smaller pieces, passing into the intestines and causing a complete obstruction. Please always mention to your regular veterinarian if you are suspicious your pet ate something it shouldn't have.