This is the urgent one
If there is one page on this site to act on immediately, it is this one. String, thread, ribbon, tinsel, dental floss, and shredded rope fibres behave completely differently from anything else a dog swallows, and they are far more dangerous.
Call us straight away, even if your dog seems entirely well. Foreign body removal surgery treats linear cases as the highest-priority category we have.
If you can see string at your dog’s mouth or anus, do not pull it.
The other end may be anchored deep in the intestine. Pulling can tear the bowel wall from the inside. Leave it exactly where it is and call.
What makes a linear foreign body different
A solid object lodges in one place and stops. A linear foreign body does something far worse.
One end anchors — typically under the tongue, or caught at the pylorus where the stomach empties. The rest travels onward, and the intestine does what intestine does: it contracts rhythmically, trying to move the string along.
Because one end cannot move, the bowel instead gathers itself up along the string, like fabric bunching on a thread. This is called plication, and it has a characteristic appearance on imaging.
Meanwhile the string is drawn taut around the inside curves of the bunched intestine. Every contraction saws it a little deeper into the bowel wall. Given time, it cuts all the way through in several places at once, spilling gut contents into the abdomen and causing peritonitis.
The signs
- Repeated vomiting, particularly persistent vomiting
- Refusing food
- Lethargy that worsens rather than improves
- A painful abdomen
- Visible string at the mouth or anus — an emergency regardless of anything else
- Fever, which suggests perforation has already occurred
Some dogs with a linear foreign body look deceptively stable for the first day. That is not reassurance; it is the window in which the damage is being done quietly.
What we look for on imaging
String itself is invisible on radiographs, so diagnosis relies on the pattern. Plicated, bunched bowel loops have a distinctive look, often with small comma-shaped or teardrop gas bubbles trapped between the folds. Abdominal ultrasound shows the plication clearly and can sometimes visualise the string itself as a bright line running through it.
The surgery
Linear foreign body surgery is more involved than removing a single lodged object. The anchor point has to be identified and released first, then the string retrieved — often through several enterotomy incisions along the length of the tract, because it cannot simply be pulled through from one end.
Any section of bowel that has been sawn through or lost its blood supply is removed and the healthy ends joined. Where perforation has occurred, the abdomen is thoroughly lavaged and broad-spectrum antibiotic cover is given.
Cost starts at around $1,200 and rises with the extent of the damage. Every price includes pre-op radiographs, pre-anesthetic bloodwork, IV fluid support, anesthesia with continuous monitoring, and post-operative medications.
Common sources worth securing
Sewing thread and spools, dental floss, ribbon and gift wrap, tinsel and Christmas decorations, shredded rope toys, string from a roasting joint — which carries the additional appeal of tasting of meat — and elastic hair ties.
What to do right now
If your dog is collapsing, has a rigid painful abdomen, a fever, or cannot keep water down, go to your nearest emergency hospital immediately.
Otherwise contact us immediately. Tell us what type of string, roughly how long, when it was swallowed, and whether any is visible. With linear foreign bodies the time between swallowing and surgery is the single biggest factor in the outcome.