What happens if esophageal stent moves?

If an esophageal stent moves from its original implanted position, it can cause several potential complications:

- Migration - The stent could migrate either upwards into the pharynx/mouth or downwards into the stomach. This leaves the original area untreated and could cause obstruction where it migrates.

- Tissue injury - A dislocated esophageal stent may rub against or press into the esophageal wall, causing pain, irritation, or ulceration of the tissue. This can be quite dangerous if it leads to perforation.

- Obstruction - If the stent flips upside down or tilts, it can partially or fully obstruct the flow of food and liquids through the esophagus. This can make swallowing difficult.

- Gastroesophageal reflux - Normally the lower esophageal sphincter prevents stomach acid from flowing upwards. However, a migrated stent may disrupt this valve mechanism and allow the reflux of stomach contents back into the esophagus.

- Infection - Bacteria may gain access into the esophagus from the stomach if the stent compromises the esophageal barrier. This could lead to esophagitis or other infections. 

- Vomiting/coughing - A dislocated stent can stimulate the vagus nerve and cause chronic coughing or vomiting reflexes. 

To correct a migrated esophageal stent, removal, and repositioning or placement of a new stent is usually required. This is done endoscopically to avoid further tissue damage. Preventing stent migration relies on proper sizing and the use of stents with anti-migration features.