A foreign body is an object that, once swallowed, is likely to get stuck in the gut and cause a blockage.
Some dogs are notorious offenders when it comes to eating foreign bodies — and certain breeds, such as Labrador retrievers who snack first and ask questions never, being especially at risk.
This does not mean cats never get foreign bodies, but they are more likely to swallow the end of a piece of wool or tinsel, which then travels into their intestine and causes the bowel to accordion into pleats.
Left untreated, a foreign body can be fatal.
If your pet swallows something he shouldn’t, it is always best to seek veterinary advice.
If you are lucky, the object may pass out the other end without a problem, but there are times when surgery is necessary to remove the errant object.
The symptoms range from the subtle to the dramatic, depending on the foreign body’s location.
If your Labrador has a piece of chewed toy lodged in his stomach, this forms an intermittent plug at the stomach exit. Thus the dog may be able to drink water and keep that down, but food is vomited back up. In this case it is difficult to predict the outcome because he might vomit the toy up, but equally the toy may pass into the intestine and cause a full-blown blockage farther down.
If the intestine is blocked, things quickly become serious.
Taking our Labrador example (sorry if you have a Lab, but you know what they are like!), if the toy enters the small intestine it becomes like a cork in a bottle, and nothing else (food or fluid) can get past this intestinal foreign body in the dog.
Initially, the dog vomits profusely, including fluids. If the bowel wall is damaged, it starts to die off and release toxins. The dog becomes unwell and is lethargic to the point of collapse. Left untreated, the dog gets dehydrated, the bowel may perforate and the patient could die.
Anything that fits into the bowel and is indigestible can potentially get stuck with devastating consequences.
Diagnosis can be a thorny issue — not only is it a matter of seeing if a foreign body is present but also working out if surgery is necessary or not.
Another problem is that not all foreign bodies show up on an X-ray. Certain objects, such as rubber balls and cloth toys, can be the same density as soft tissue of the abdomen, and thus radiographs may not be particularly helpful. One way around this is a barium meal, which tracks the passage of barium through the bowel to see if it gets stuck anywhere.
Another option is an ultrasound scan, which requires a skilled operator to identify subtle signs, such as dilated loops of bowel or gut contents, that are sloshing around and not passing down.
Some signs do flag that emergency surgery is necessary, such as distended loops of bowel or dense foreign bodies, like stones, causing a complete obstruction.
A firmly wedged foreign body is a definite case for surgical removal. This surgery is not without risk because the complication rate for bowel surgery is high.
This video shows Clover the dog after swallowing a stone (warning: minor graphic surgical scenes after the 1:00 mark):
Leaving a foreign body in place, however, carries a much higher risk of bowel perforation, peritonitis and death.
Sometimes if the object seems like it is slowly making its way out, then close monitoring of its progress is appropriate until it is safely passed or stops moving and becomes critical.
Vigilance is the answer!
Check your garden for hazards such as stones or fruit. Don’t leave a pet unattended with a toy (in case they chew and swallow pieces) unless it is designed to be indestructible.
There are dogs — serial offenders — who will run off and eat things they shouldn’t. Rather than risk a foreign body, it is best to muzzle these animals for their own good during walks.
- Small Animal Surgery. 4th edition. Theresa Welch Fossum. Publisher: Mosby.
This pet health content was written by a veterinarian, Dr. Pippa Elliott, BVMS, MRCVS. It was last reviewed Dec. 11, 2014.