Fish bones are actually one of the most common reasons people end up in the emergency department – particularly in Asian countries, where diets tend to include a lot of fish. In fact, the problem is so great in China that specialist fish bone removal clinics have popped up all over the place, writes Adam Taylor in The Conversation.
Although fish are a good source of many minerals, protein and heart-healthy fatty acids, they also contain multiple small, delicate "pin" bones – usually in the fillet.
Cod, for instance, have about 17 pin bones, and salmon have around 30, though some fish can have more than 100.
This means that despite the care taken during the food prep process, some may inadvertently slip through. These bones can be dangerous if swallowed accidentally, and choking is just one of the serious complications that they can cause.
Fish bones typically become lodged in the tonsils at the back of the throat, in the pharynx at the back of the mouth, the piriform sinus (a small hollow that plays a role in swallowing) and, of course, the oesophagus (the canal connecting the throat to the stomach).
If you’ve ever accidentally swallowed a fish bone, you’ll have probably experienced coughing, a prickly or “something stuck” sensation in the throat, as well as pain or difficulty swallowing and spitting up blood.
However, they don’t always cause symptoms – and some people end up living unknowingly with a fish bone stuck in their throat.
For instance, in 2012, a 69-year-old Japanese woman went to hospital complaining of a swollen neck, only for doctors to discover she had a 32mm fish bone which had been lodged in her throat for nine months.
Undiscovered fish bones can also migrate around the neck. Repeated swallowing can also result in the bones penetrating the wall of the oesophagus and moving into the tight spaces in the neck.
Here, the bone poses a high risk to the vast number of critical nerves and blood vessels that pass through the neck, such as the carotid artery, one of the major vessels supplying blood to the brain.
Bones can also pierce the thyroid gland, which can cause abscesses and inflammation. This can also lead to sepsis, a rare but incredibly dangerous complication.
In some cases, lodged fish bones have even managed to migrate into the neck’s muscles and under the skin. They can even pop out of the skin too, as happened recently to one Thai woman.
Any bones that manage to migrate out of the throat are a surgical emergency as there’s no way to dislodge them otherwise. These bones can also cause infections in the spaces around the heart or migrate into the spinal cord, leading to secondary infections which could cause paralysis.
This is why it’s imperative to remove a bone as soon as possible after it has been accidentally swallowed.
What to do
Stuck fish bones can be removed in various ways. For some people, a forceful cough will be enough to eject it. This technique is most effective in cases where the bone is stuck in the airway, rather than the oesophagus.
But one problem with coughing is that instead of ejecting it, it could dislodge the bone and allow it to pass into the stomach and through the intestines, where there’s a risk of perforation.
Bones that are stuck in the wall of the oesophagus could potentially move through the body, but many cases will require endoscopic removal.
Some tips suggest that eating something like bread or banana can force the bone down, but there’s no scientific evidence to support this remedy. It may even further block the airway or oesophagus – and could potentially make things worse by lodging the bone further into the tissue.
So if coughing doesn’t help and you still have symptoms, seeking medical advice is the next sensible step.
Where a person is unable to speak or breathe, abdominal thrusts may be needed to help dislodge the offending fish bone (or other item). If necessary, call emergency services and seek urgent medical support.
Adam Taylor, Professor of Anatomy, Lancaster University
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