Sewing Thread: A Little-Known Menace to Cats
It is common sense that cars, coyotes, and falling bookshelves are dangerous to cats. Most people know that lilies can cause kidney failure, and that Tylenol is poisonous to our feline friends. Folks on the West Coast are generally aware that foxtails can lodge in cats' eyes.
But then there are the little-known menaces. I'm talking about seemingly innocuous items that can lead to catastrophic complications when mixed with cats. For instance, several months ago I wrote about a cat who could have died as a result of a grass blade lodged in his pharynx (throat). Grass seems harmless enough, but if a cat coughs at just the right time when he's trying to swallow a grass blade, or if he vomits grass, the blade can get stuck in the throat. Pain and infection result. The cat's sore throat makes it impossible to eat or drink. Starvation and dehydration occur. The problem can be fatal if not treated.
Fortunately it is relatively easy to remove a blade of grass from a cat's throat. Even a cat with advanced symptoms can usually withstand the brief anesthetic procedure to remove the foreign body, and recovery is generally rapid.
However, not all seemingly-innocous-but-in-fact-dangerous items can be so easily treated. One, in particular, is especially devastating. I am referring to sewing thread.
What image is more iconic than that of a kitten with a ball of yarn? Cats and kittens generally love to play with yarn, thread, dental floss, fishing line, ribbon, and Christmas tinsel. Although these objects seem completely benign, they in fact have the potential to wreak devastation when swallowed. They can lead to a condition called gastrointestinal obstruction secondary to linear foreign body.
All of these items have something in common: they are long, thin, and thread-like. In a word, they are linear. Why are they dangerous?
In fact, cats often can swallow these types of items without any problem. As long as the item moves freely through the intestinal tract, it can pass and be cleared in the feces.
The issues occur when a linear item becomes anchored somewhere in the digestive system. The most common anchor point is the tongue; in these cases the item is caught under the tongue and then swallowed, resulting in an anchored linear item descending into the stomach and intestines. In other cases a portion of the linear item balls up and lodges in a hairball or other piece of foreign material. The result is the same: an anchored linear item descending through the gastrointestinal tract.
Intestines move food and other ingested items from the front of the system to the rear of the system by means of a process called motility. Motility involves coordinated movement of the smooth muscles of the bowels. If an item is freely mobile, it moves from front to back. If, however, a linear item is anchored it cannot move when the intestines take hold of it. Instead, the intestines move. They bunch up tightly towards the front and the system grinds to a halt. Sometimes even worse things happen.
Many years ago I treated an adorable young male orange tabby. His owner had noticed lethargy, vomiting, and lack of appetite and thirst for several days.
When I evaluated him I could tell immediately that he was very ill. He was lethargic and he sat with his back arched in pain. His head lolled towards the ground. He was dehydrated, and his hair was unkempt. Unkempt hair is a sign that a cat is too sick to groom. He looked like he had recently lost weight. He vocalized in pain when I gently palpated his abdomen. And his breath was atrocious.
Whenever I see a sick cat, I always look under the tongue. This can be done by opening the cat's mouth and gently pressing on the soft portion of the chin between the mandible bones. The cat did not like this and I couldn't get a very good look, but I was able to see enough to make my diagnosis. The underside of the cat's tongue was severely inflamed with a linear laceration extending around the base. There had to be a linear item buried in there.
I explained the diagnosis and its gravity to the shocked owner. I recommended immediate treatment, and the owner approved. The cat was started on IV fluids, gastrointestinal protectants, pain killers, and antibiotics. Radiographs showed a classical "string of pearls" pattern of gas in the abdomen consistent with a linear foreign body. It was also hard to distinguish the individual organs in the abdomen. This was an ominous sign, implying that the intestines might have perforated or been lacerated leading to fluid in the abdomen. Surgery was urgently needed.
Bloodwork showed an elevation in blood urea nitrogen -- or BUN -- consistent with dehydration. However, my level of concern continued to rise. An elevated BUN also can be a sign of intestinal bleeding. A complete blood count showed a decrease in white blood cells. This was consistent with sepsis.
My patient was far from a good anesthetic candidate, but he was only going to get worse until the foreign item was removed. Once he was stabilized and rehydrated, we proceeded to surgery.
Evaluation under the tongue revealed black sewing thread within the linear laceration. It was very firmly embedded, and I cut it and affixed hemostats to the ends in order to keep the thread from disappearing into the esophagus (although in many cases the thread is pulled through the esophagus and removed through the stomach, it is best to keep control of the thread until the situation is fully evaluated).
When I opened the abdomen, my worst fears were confirmed. Almost the entirety of the small intestine was bunched up near the stomach. There was abnormal fluid in the abdomen consistent with intestinal leakage. My assistant released the hemostats, and by making a series of incisions, I was able to remove the foreign body and relieve the intestinal bunching.
The intestines had suffered grave insult. Several areas were purple, consistent with segmental death due to lack of blood flow. Worse than this, however, was the damage that had been done by the thread itself. As the intestines had bunched around the thread, the thread had acted like a saw. It had lacerated the walls of almost the entire intestinal tract. The damage was so severe that there was absolutely no hope of the cat recovering.
I called the owner with a heavy heart and gave her the news. She asked that the cat be euthanized immediately on the surgical table. I performed the act.
Fortunately linear foreign bodies do not always lead to such devastation. I have been involved in many successful surgeries that led to complete recoveries. But with linear foreign bodies time is of the essence. They need to be treated before intestinal damage occurs.
Remember that it is not normal for a healthy animal to go even a full day without eating. Loss of appetite does not simply mean that the cat isn't hungry. It means something's wrong. If your cat stops eating, or shows other symptoms such as lethargy and vomiting, it's best to get to the vet that same day. Rapid action can help to prevent tragedies like the one I just described.
Remember as well that thread, string, yarn, ribbons, tinsel, and other linear items, unfortunately, can kill cats.
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