Gastric foreign bodies

　　First, Etiology

　　Exogenous foreign bodies refer to the swallowing of foreign objects into the stomach, which is not uncommon in clinical practice. Foreign bodies are diverse, with common ones including buttons, dentures, safety pins, coins, tacks, keys, and animal bone spurs. In addition, foreign bodies left in the gastric cavity during surgery (such as instruments and sterilized gauze) can also be occasionally seen. Endogenous foreign bodies refer to those passing through the pylorus, such as roundworm clumps, and the perforation of the gallbladder into the duodenum causing gallstones to move into the stomach.

　　Second, Pathogenesis

　　1, Accidental ingestion or deliberate swallowing is more common in children, such as accidentally ingesting small toys, hairpins, keys, and coins. In adults, it is more common with dentures and animal bones. Deliberate swallowing is common in criminals and mentally disordered individuals, and the foreign bodies swallowed are diverse, such as pens, sewing needles, lighters, nails, broken glass, and toothbrushes.

　　2, Iatrogenic causes include residual sutures, drainage tubes, etc.

　　3, Gastric stones include four types: vegetable, animal, medicinal, and mixed. Clinically, vegetable gastric stones caused by eating persimmons, black jujubes, hawthorn, etc., are more common, and they are more likely to occur in patients with reduced gastric motility, such as those with dyspepsia, gastric atony, or after subtotal gastrectomy. After eating a large amount of persimmons on an empty stomach, tannic acid in the persimmons combines with protein under the action of gastric acid to form a larger molecule called tannic protein that is not easily soluble in water, which precipitates in the stomach. Tannic protein, gum, and fruit acids bind the persimmon skin, seeds, and plant fibers together, forming gastric persimmon stones.

　　Common complications caused by gastric foreign bodies include:

　　1. Foreign body retention

　　2. Gastrointestinal obstruction

　　3. Gastrointestinal perforation:An abrupt onset of severe upper abdominal pain, presenting as a continuous cutting or burning pain, quickly spreading to the entire abdomen; often accompanied by sweating. Cold extremities, palpitations, shortness of breath, and other shock symptoms; nausea and vomiting, bloating, fever may occur.

　　4. Formation of abscesses:This is caused by foreign bodies, and abscesses are localized accumulations of pus in the tissues, organs, or body cavities during the acute infectious process, which appear due to the necrosis and liquefaction of pathological tissue, surrounded by a complete pus wall.

　　5. Internal or external fistula

　　6. Gastrointestinal bleeding:If the blood remains in the stomach for a long time after bleeding, it becomes acidic hemoglobin due to the action of stomach acid and appears brownish. If the bleeding is fast and the amount is large, the vomit is bright red. Black stools or tarry stools indicate bleeding in the upper gastrointestinal tract.

　　Approximately 20% to 30% of ingested foreign bodies are obstructed in the esophagus and remain there, while more than 80% of gastric foreign bodies can be excreted from the stomach cavity and excreted from the intestines in feces, rarely causing discomfort or only mild upper abdominal dull pain, bloating, nausea, and other symptoms. When the foreign body is large, it may become lodged at the pylorus, duodenojejunal flexure, ileocecal valve, and other locations. Obstruction of the pylorus often causes the patient to experience upper abdominal pain, bloating, vomiting. Direct injury to the gastrointestinal mucosa by the foreign body or long-term obstruction can cause local mucosal erosion and ulceration, leading to gastrointestinal bleeding. When a foreign body causes perforation, the patient may exhibit signs of peritonitis. Sharp pointed foreign bodies such as needles can pierce the gastrointestinal wall to form localized abscesses or granulomas, and may also penetrate the gastrointestinal wall and migrate to other abdominal sites.

　　Prevention of gastric foreign bodies:

　　1. Prevent exogenous foreign bodies from entering the stomach (especially in children).

　　2. Children should not play games that lead to circular common objects entering the stomach.

　　3. Pay attention to prevent psychiatric patients or those with suicidal tendencies from ingesting certain items.

　　6. Avoid excessive intake of fresh persimmons, fresh jujubes, and certain foods.

　　Check for the presence of foreign bodies excreted in the feces.

　　1. X-ray examination

　　Metallic foreign bodies and gastric foreign bodies with metallic parts can be identified by X-ray examination for their shape, size, quantity, and position. It is also possible to dynamically observe the migration of foreign bodies. Larger metallic foreign bodies can be detected under X-ray fluoroscopy, but fine metallic foreign bodies are easily missed and require radiographic examination. Whether X-ray fluoroscopy or radiographic examination is used to examine gastric foreign bodies, it is necessary to instruct the patient to remove their upper clothing, initially understand the shape, size, and approximate position of the gastric foreign body under fluoroscopy, and turn the body position to observe whether the foreign body is in the stomach. If there is any suspicion, check the patient's abdominal and back skin condition to avoid mistaking abdominal and back skin metallic foreign bodies for gastric foreign bodies.

　　For X-ray examination of non-metallic gastric foreign bodies, it is advisable to use low-density barium or gas-barium contrast, which can display the outline and position of the gastric foreign body.

　　2. Fiberoptic endoscopic examination

　　Since fiberoptic endoscopic examination has been widely used in clinical practice, as long as the foreign body is not damaged or impaled in the esophagus at the time of swallowing, both metallic and non-metallic foreign bodies can be examined by fiberoptic endoscopy, especially for non-metallic foreign bodies that cannot be displayed by X-ray. If there is a reliable history of swallowing foreign bodies, routine fiberoptic endoscopic examination should be performed to avoid delaying the diagnosis and treatment.

　　Some patients may have a clear history of swallowing foreign bodies, but without X-ray or fiberoptic endoscopic examination equipment, and the patients do not have obvious symptoms or signs. They should be closely observed, and the stool should be checked carefully for the excretion of foreign bodies. If there is no excretion of foreign bodies within 5 to 7 days, and the patient has obvious abdominal symptoms and signs, it is necessary to transfer the patient to a higher-level hospital for further examination to clarify the diagnosis in a timely manner.

　　Diet should be regular and reasonable, mainly high-protein and high-vitamin foods. Choose high-nutritional value plant or animal proteins, such as milk, eggs, fish, lean meat, and various bean products. Various fresh vegetables and fruits are rich in vitamins and have high nutritional value.

　　First, treatment

　　1. Natural excretion method: Approximately 90% of foreign bodies that are accidentally swallowed can be excreted naturally. However, some sharp foreign bodies (such as toothpicks, nails, sewing needles, blades, glass fragments, etc.) and toxic substances (such as batteries containing strong alkali) are prone to damage the mucosa of the digestive tract, causing gastric perforation, and can lead to systemic poisoning symptoms. In such cases, active measures should be taken to deal with the foreign body. The average time for natural excretion of foreign bodies is about 5 days. Generally, round foreign bodies greater than 2cm, elongated foreign bodies greater than 5cm x 2cm, and those with blunt edges can be helped to excrete naturally with liquid paraffin or laxative herbs. If necessary, endoscopy or surgery can be performed to retrieve the foreign body.

　　2. Endoscopic retrieval method: Endoscopic retrieval of foreign bodies is convenient, simple, effective, and can avoid the pain of surgery, making it the main method for the treatment of gastric foreign bodies. When retrieving gastric foreign bodies under endoscopy, attention should be paid to the methods and techniques:

　　(1) Prepare for preoperative work:

　　① Inquire in detail about the history of swallowing foreign bodies to understand the location, shape, size, and time of swallowing. If it is a metal foreign body that can be easily detected by X-ray examination, X-ray fluoroscopy can be performed to select appropriate instruments and methods; it is generally not advisable to perform barium swallow examination. It is recommended to fast for more than 4 hours before the operation to prevent regurgitation of gastric contents that may affect the operation field. ② For foreign bodies with special shapes, it is necessary to use replicas for in vitro retrieval experiments before the operation, select simulated action plans, and test repeatedly in vitro to ensure accuracy before retrieval under endoscopy. ③ Children or some adults with excessive mental tension may be given appropriate amounts of sedatives (such as diazepam, midazolam, etc.) or choose intravenous anesthesia as needed.

　　(2) Select appropriate instruments and methods based on the shape of the foreign body:

　　① Sharp, irregular foreign objects: such as chicken bones, fish bones, etc., which are hard objects, can be securely held with forceps, rat teeth forceps, or a net basket, and the foreign object is withdrawn from the site of insertion, attention should be paid to make the long axis of the foreign object parallel to the esophagus and slowly withdraw the endoscope. To avoid injury to the stomach and esophageal wall of such foreign objects, the following methods can be used: valve protection method: use silk thread to tie the two wall valve tips forward and the root opposite to the tip of the endoscope, so that the two valves wrap each other to form a ring, and then fold the valve tips back to the rear and tightly adhere to the body of the endoscope, apply silicone oil on the surface, and fix it with a snare device outside the endoscope, and then pull it into the stomach together with the snare device. When the foreign object is snared, release the snare device and lift it up, so that the wall valves automatically open, then push the snare device forward to wrap the foreign object, even if it is not wrapped well, when the endoscope is withdrawn, the gastroesophageal junction can also tightly wrap the valves around the foreign object, thus smoothly and safely removing the foreign object from the body. Sheath protection method: put a reversible protective sheath on the outer side of the endoscope, wrap the foreign object after picking it up, and push the sheath to wrap the foreign object before withdrawing. ② Flat foreign objects: such as watches, keys, coins, buttons, button batteries, saw blades, knives, hairpins, etc., are usually picked up with rat teeth forceps or crocodile mouth forceps, and when the endoscope is withdrawn, the largest diameter of the foreign object should be placed on the forehead to make it easier to pass through the pharynx. If a watch is removed, take the side edges from left to right. ③ Long rod-shaped foreign objects: Commonly found objects such as pens, ballpoint pens, bamboo chopsticks, toothbrushes, thermometers, glass tubes, long batteries, etc., can usually be successfully removed with snare devices and net baskets. When removing such foreign objects, the assistant should make the patient's head tilt back as much as possible to make the pharynx and oropharynx form a straight line, which is conducive to passing through. ④ Spherical foreign objects: such as glass balls, fruit kernels, etc., are easy to fall off when snared, and basket-type or four-claw foreign body forceps are often used to tightly grasp or hold them with the endoscope. ⑤ Keys, rings, and other pierced foreign objects: can be removed using the pull-line method. One end of the line is left outside, and the other end is sent through the hole of the foreign object with a biopsy forceps, and then clamped on the other side of the hole to form a loop and pulled out. ⑥ For foreign objects in infants and young children's stomach, bronchoscopes can be used instead of endoscopes to remove foreign objects.

　　3. Surgical removal method When foreign objects are large and remain in the stomach, or when endoscopic treatment fails, or sharp and toxic foreign objects have entered the small intestine, causing harm to the body, foreign objects should be removed surgically in a timely manner.

　　II. Prognosis

　　Early detection and diagnosis, followed by internal medicine treatment, endoscopic biopsy or surgical treatment, have a relatively satisfactory clinical prognosis.