TL;DR: A linear foreign body, such as swallowed string or yarn, is a life-threatening emergency for cats that requires immediate veterinary attention. Never attempt to pull visible string or induce vomiting at home, as this can cause fatal internal lacerations.
What is a linear foreign body and why is it dangerous for my cat?
When a cat swallows a long, thin object like string, yarn, dental floss, or sewing thread, it is medically classified as a linear foreign body. Unlike a solid object that might pass through the digestive tract, linear objects are particularly dangerous because one end often becomes anchored (frequently under the tongue or at the stomach exit), while the rest of the string moves into the intestines. As the intestines attempt to move the string along via peristalsis, they begin to bunch up or 'pleat' like a curtain on a rod, which can lead to fatal intestinal wall lacerations.
Is a linear foreign body a veterinary emergency for my cat?
- Contact an emergency veterinarian immediately; the urgency level for a linear foreign body is high and life-threatening.
- Understand that the sawing action of the string against the intestinal lining can cause perforations and lead to septic peritonitis within hours or days.
- Do not attempt to induce vomiting at home under any circumstances.
- Never pull on any string visible from the mouth or the rectum, as this can cause immediate, severe internal tearing.
How does taking a photo of the ingested object help with veterinary triage?
- Take a clear photo of the original object or the remaining piece of string next to a common item for scale, such as a coin or a pen.
- Show this photo to your veterinary team to help them estimate the length, material, and texture of the ingested object.
- Identify if the string was attached to a needle, bell, or lure, as this information changes the surgical approach and priority for diagnostic imaging like X-rays or ultrasound.
Clinical Context (Merck Veterinary Manual)
Linear foreign bodies, such as string, yarn, or dental floss, in cats can be particularly challenging as they may not be palpable, making assessment of their length difficult. Exploratory laparotomy is indicated if a foreign body distal to the pyloric region is present, if there are foreign bodies at multiple locations, or if there are signs of septic peritonitis. If a linear foreign body is present in the stomach and extends into the small intestine, gentle manipulation may free the foreign body from its distal attachments, allowing removal through a gastrotomy incision; otherwise, multiple enterotomies may be indicated. The entire gastrointestinal tract must be inspected for objects that could cause obstruction, and the vitality of the gastrointestinal tract must be assessed, with areas of perforation or ischemia resected. Radiographs should be taken before recovery from anesthesia to exclude the presence of multiple foreign bodies.
Chapter: Surgery, Gastroenterology
Source: The Merck Veterinary Manual, 11th Edition (Page 392)