Pete the Vet: When dogs swallow objects that obstruct their digestive tract
Even adult dogs don’t think rationally, and so foreign bodies are seen in dogs of all ages
Dogs are prone to a particular digestive hazard: the risk of swallowing an indigestible object that becomes lodged in the stomach or intestines. This is common: dogs have an enthusiastic appetite, with no cognitive understanding of the risk of swallowing such objects.
Gastrointestinal foreign bodies are seen less often in other species, but they can still happen, as I know from personal experience. When I was just three years old, my brother gave me a glass of orange juice with brightly coloured wooden toy cubes floating in it: “pretend” ice cubes. I happily drank the drink and swallowed the “ice cubes” at the same time. My parents were horrified, and soon I was too, because for the next three days I had to squat on a plastic potty while my poor mother inspected my output. In due course, the “ice cubes” emerged, and there was no need for an operation to remove them.
Unfortunately, even adult dogs don’t think rationally, and so foreign bodies are seen in dogs of all ages. The most common objects include plastic/rubber balls, stones, squeaky toys, bones, corks, bottle caps, corn cobs, large fruit stones and small items of clothing. Generally, these objects are (just) small enough to be swallowed, but then either too big to pass from the stomach into the intestines (a gastric foreign bodies) or small enough to leave the stomach, but then too big to pass down the small intestines through the remainder of the digestive tract (intestinal foreign bodies). Sometimes, sharp objects (needles, fish hooks, etc.) are swallowed, and these can be even more dangerous, causing physical punctures and lacerations to the lining of the stomach or intestines. So-called linear foreign bodies (strings, ribbons, threads) can also cause serious problems, as one end can become stuck, and the rest of the object can continue to move down the digestive tract. The intestines then become corrugated, like a shirt sleeve being pushed up an arm. Serious damage to the intestines follows.
Sometimes, owners witness a hazardous object being swallowed. A typical example would be a dog stealing a bone and being chased by their owner. The dog hungrily bolts the bone as fast as possible, to stop their owner grabbing it off them. In some cases, the owner is too late, and the bone has been swallowed. Other examples of objects being seen as they are swallowed include toys, balls and items of clothing.
I was recently consulted about a dog who had scoffed a visiting relative’s sock. The family knew that their pet was prone to chewing (and swallowing) socks, as he had previously needed surgery to have a sock removed. The visitor didn’t know about this risk, and he took off his socks in a public room, moments later noticing that one of his socks had gone missing. The family knew exactly what had happened: twenty minutes later, the dog was in my consulting room. I gave him an injection to induce vomiting, and the sock duly emerged from his stomach. The need for a complex and hazardous operation to remove it from his stomach was avoided.
It’s more common for an object to be swallowed without the owner realising. The issue only becomes apparent when the animal becomes unwell as a consequence of the obstruction which later develops, two or three days later.
The most common signs noticed by owners are dullness, inappetence and vomiting. Affected dogs may become thirsty, sometimes bringing the water back up again. Such animals need to be brought promptly to the vet. Occasionally, a simple physical examination is enough to make the diagnosis: I remember many cases where I have been able to feel a solid object like a stone by pressing my fingers in to a dog’s side. More often, further investigations such as x-rays or ultrasound are needed. So-called radio-opaque foreign bodies (such as stones and bones) can be seen very easily on x-rays, while “radio-lucent” objects (such as some plastics and fabrics) are invisible. In these cases, vets check x-rays for unusual gas patterns that suggest that the normal flow of intestinal contents has been held up, like the build up of traffic that results from the obstruction of a road by a car crash.
The operation to remove intestinal obstructions is delicate and hazardous: there’s a 20% mortality rate. However there’s no other answer: such obstructions absolutely need to be surgically removed.
Last week, I treated an unusual seasonal foreign body. Poppy, an eight month old Labrador cross, was brought to my clinic because she had broken her leg while out on a walk. The vet who initially examined her noticed that as well as the damaged, painful leg, she seemed to have an unusually uncomfortable abdomen. The broken leg needed to be x-rayed, so an x-ray of the abdomen was taken at the same time. A 5cm long sewing needle was visible in the area of her stomach. I had to carry out an emergency operation to remove this: the needle had already punctured her stomach, which is why she was in pain. The operation went well, and she made a full recovery. It turned out that she had been watching while the stuffing was stitched into the turkey, the needle must have been left on the counter afterwards. Poppy had a habit of taking objects off kitchen counters when nobody was watching, so she must have quietly scoffed the needle, coated with turkey flavour as it must have been.
The best answer, of course, is to prevent dogs from swallowing foreign bodies in the first place. Keep all potentially hazardous objects out of dogs’ reach. Easy to say, but more difficult to achieve in practice.
