Foreign Body Ingestion in Children: From a Harmless Incident to a Life-Threatening Emergency

1. Introduction

Accidental ingestion of foreign bodies is a common occurrence in childhood; in young children, introducing objects into the oral cavity is a normal developmental stage as they explore their environment [1]. In older children, it occurs mainly in those with psychological or neuropsychological disorders [2].

2. Epidemiology

In most cases, ingested foreign bodies are evacuated through the stool within a few days without complications; endoscopic removal is necessary in only 10-20% of cases, and surgical intervention in less than 1% of patients. The majority of ingestions are accidental, particularly in children younger than 5 years old, with the highest incidence reported in those aged 2-3 years [3,4].

In recent years, the incidence of accidental ingestion of button batteries and magnets has increased significantly, due to their growing use and the presence in children’s toys [5,6].

3. Pathophysiology

Complications are more likely in children with pre-existing gastrointestinal (GI) tract disorders, but they are also reported in children with no known risk factors, some of them having previously unidentified anatomical or functional abnormalities [7]. Most foreign bodies can become lodged in the esophagus at the site of physiological strictures, such as the thoracic inlet, the aortic arch in the middle esophagus, and the gastroesophageal junction, leading to different grades of obstruction.

Batteries, especially button types, even when discharged, react with saliva and with moist esophageal mucosa, generating a local stream that triggers electrical hydrolysis, which leads to the release of hydroxyl radicals at the negative pole of the battery, causing severe damage through corrosion. These burns occur within 1 hour, followed by severe coagulative necrosis [8]. The electrical voltage and especially the impact duration are determining factors that determine the severity of the injury. Lithium batteries, in particular, can generate higher voltage and electrical current, leading to increased hydroxide accumulation. Other mechanisms by which complications arise include local pressure necrosis, corrosive injuries caused by battery leakage, and heavy metal poisoning [9].

Neodymium magnets are 20-30 times stronger than standard magnets. Even if they are swallowed separately and pass individually through the GI tract, they strongly attract to each other through the intestinal walls, eroding the tissues between them, causing perforations in up to 50% of cases of ingestion within 12 to 48 hours [10].

A particularly serious situation arises when a magnet and a coin-type battery are swallowed simultaneously, as the combination of injuries produced by local current flows and erosion caused by strong magnetic attraction leads to serious complications.

Superabsorbent polymers, which are derived from hydrophilic acrylic acid polymers, are those water-filled bead toys that can increase their initial volume by up to 60 times when ingested, expanding considerably in wet conditions, but also diapers and feminine hygiene products. Their ingestion poses significant risks, such as intestinal obstruction, perforations, and even death, usually requiring surgical intervention for their removal [11].

Sharp objects can become lodged at the base of the tongue, in the vallecula, in the tonsillar fossa, in the pyriform sinuses, or can perforate the pharyngeal wall and penetrate deep structures [12]. In fact, they can cause perforations at any level of the digestive tract.

Trichobezoar is the result of chronic hair ingestion (one’s own, from dolls, or from pets), a behavior called trichotillomania. This can fill the stomach and extend into the duodenum or even the colon. Inspired by the Grimm brothers’ fairy tale, the extension of the bezoar into the small intestine is called "Rapunzel syndrome" [13].

4. Evaluation

4.1. Clinical Evaluation

In all cases, the clinical examination must be preceded by a detailed medical history. However, the caregivers may not have noticed the ingestion, and therefore, clinical suspicion is extremely important.

Most foreign bodies pass through the GI tract without causing any complaints. When symptoms do occur, they are mild and nonspecific: abdominal pain, nausea, vomiting, or a feeling of abdominal fullness. Severe symptoms arise from complications and depend on the type of foreign body, the time since ingestion (e.g., for batteries), the location where it is lodged, and any preexisting conditions of the patient. In all children, after a detailed oropharyngeal examination, it is also important to assess the airway to exclude a proximal airway obstruction.

A foreign body lodged in the esophagus can cause complications manifested by chest pain, a foreign body sensation, coughing, dyspnea, odynophagia, dysphagia, and vomiting. In severe cases, hematemesis or signs of mediastinitis may occur. Complete obstruction of the esophagus can lead to excessive salivation, which can indirectly compromise the airways due to secretions accumulation and the risk of aspiration. When complications occur in the stomach or gut, abdominal pain, vomiting, hematemesis, or GI bleeding may occur [14].

Trichobezoar symptoms include abdominal pain, growth disorders or weight loss, anorexia, GI hemorrhage, vomiting, anemia, and even symptoms of ileus or perforation [15].

It is important to note that foreign body ingestion should be considered in any child admitted to the hospital with digestive or respiratory symptoms that do not respond to treatment.

4.2. Imagistic Evaluation

Plain radiographs of the neck, thorax, and of the entire abdomen are useful for identifying the type, size, and location of ingested objects, especially the radiopaque ones (batteries, magnets, coins, etc.), though they are less effective for radiolucent materials such as food fragments, fish bones, or glass shards.

An important point is that button batteries can be confounded with coins on a simple X-ray, leading to management errors with potentially catastrophic consequences. The batteries are visible on chest X-rays as a "double contour" or "halo" sign in the anteroposterior projection, due to their architecture, which has an upper part (the positive pole) and a lower part (the negative pole), creating two concentric outlines.

Radiographic investigation is not routinely necessary and should not delay endoscopic removal; it is most indicated for detecting complications such as esophageal perforation (pneumomediastinum) and gastric or intestinal perforation (pneumoperitoneum).

Multiple neodymium magnets can appear on X-ray as a single magnet; in these cases, lateral radiographs should be taken in order to confirm their number.

Serial radiographs allow the displacement and elimination of radiopaque bodies to be monitored. Additionally, lateral neck X-rays play a crucial role in revealing edema or inflammation, potentially caused by impaction of a foreign body and perforation of the cervical esophagus [16].

Contrast radiography should not be performed when a perforation is suspected. In addition, aspiration of the contrast medium is associated with a significant risk of pulmonary edema.

Computed tomography (CT) offers greater sensitivity for identifying radiolucent objects and complications, while magnetic resonance imaging (MRI) has a higher sensitivity, but it is not available as an emergency investigation, being used primarily for post-extraction monitoring (e.g., button batteries) [17,18].

5. Management

The management of a child who has ingested a foreign body begins with determining whether endoscopic removal is necessary and, if this is the case, in establishing the degree of urgency. Treatment depends on the type, size, and location of the object, as well as the patient’s symptoms. Objects impacted in the oropharynx require ENT examination.

In this context, we emphasize the role of the multidisciplinary team, which includes the pediatrician or emergency physician who first examined the patient, the imaging specialist, the otolaryngologist, the gastroenterologist, the anesthesiologist, and, when the situation requires it, the surgeon.

Once the indication for endoscopy has been established, the appropriate equipment must be prepared: a standard adult flexible gastroscope is suitable for children over one year of age or weighing more than 10 kg, while a smaller endoscope, < 6 mm, is recommended for children weighing less than 10 kg or when esophageal narrowing is suspected [19].

It should be pointed out that there is no absolute consensus among the different guidelines, but the recommendations are very similar. For example, the NASPGHAN (North American Society for Pediatric Gastroenterology, Hepatology & Nutrition) guidelines (in 2015) and the ESGE (European Society of Gastrointestinal Endoscopy) clinical guidelines (in 2016) divide procedures into three categories: major emergencies, emergencies, and non-emergencies [20,21].

Some countries have their own national guidelines. In this context, it is important to mention the guidelines of the Italian Society of Pediatric Gastroenterology, Hepatology, and Nutrition (SIGENP) and the Italian Association of Hospital Gastroenterologists and Endoscopists (AIGO), which provide clear and very useful recommendations, classifying cases into four categories of urgency: emergency (<4 hours), urgency (<24 hours), early elective (<48 hours), and elective (>48 hours) [22].

Table 1. Recommended timing for foreign bodies extraction, according to SIGENP and AIGO [22].

1. Emergency (requires immediate intervention, in<4 h ): -button batteries (< 2 hours) -sharp-pointed foreign bodies in the esophagus. stomach or duodenum -proximal blunt foreign bodies and food bolus causing complete esophageal obstruction (inability to manage secretions) and/or respiratory symptoms -airway compromise: stridor, choking, severe respiratory distress -button batteries in the stomach in children ˂5 years old -blunt foreign bodies in the duodenum causing symptoms

2. Urgency (requires intervention in <24 h) -asymptomatic or mildly symptomatic blunt foreign bodies in the esophagus -non-sharp/non-battery objects lodged in the esophagus without complete obstruction -multiple magnets/long objects in the stomach -blunt foreign bodies in the stomach causing symptoms -disk batteries in asymptomatic patients and/or in >5years old

3. Early elective (requires intervention in <48 h) -objects > 2.5 cm in diameter or >6 cm in length in the stomach in asymptomatic patients -asymptomatic button batteries passed into the stomach can be monitored for 48h

4. Elective (requires intervention in >48 h) -blunt foreign bodies failing to pass spontaneously through the stomach or duodenum after 4 weeks -blunt foreign bodies failing to pass spontaneously through the colon

Table 1. Recommended timing for foreign bodies extraction, according to SIGENP and AIGO [22].

1. Emergency (requires immediate intervention, in<4 h ): -button batteries (< 2 hours) -sharp-pointed foreign bodies in the esophagus. stomach or duodenum -proximal blunt foreign bodies and food bolus causing complete esophageal obstruction (inability to manage secretions) and/or respiratory symptoms -airway compromise: stridor, choking, severe respiratory distress -button batteries in the stomach in children ˂5 years old -blunt foreign bodies in the duodenum causing symptoms

2. Urgency (requires intervention in <24 h) -asymptomatic or mildly symptomatic blunt foreign bodies in the esophagus -non-sharp/non-battery objects lodged in the esophagus without complete obstruction -multiple magnets/long objects in the stomach -blunt foreign bodies in the stomach causing symptoms -disk batteries in asymptomatic patients and/or in >5years old

3. Early elective (requires intervention in <48 h) -objects > 2.5 cm in diameter or >6 cm in length in the stomach in asymptomatic patients -asymptomatic button batteries passed into the stomach can be monitored for 48h

4. Elective (requires intervention in >48 h) -blunt foreign bodies failing to pass spontaneously through the stomach or duodenum after 4 weeks -blunt foreign bodies failing to pass spontaneously through the colon

This guide also notes that asymptomatic individuals with no prior medical history who have ingested small, non-hazardous objects will receive conservative treatment.

Patients exhibiting respiratory symptoms, hypersalivation, or recurrent vomiting are also considered emergencies. However, certain high-risk objects require urgent endoscopic removal within the first two hours, even in the absence of symptoms, to prevent serious complications such as perforation, obstruction, or fistula formation. These include button or disc batteries lodged in the esophagus, multiple magnets or a magnet ingested alongside a metal object, large or obstructive foreign bodies in the esophagus, and sharp objects in the esophagus, stomach, or duodenum.

Any button battery detected in the esophagus is an emergency and requires immediate endoscopic removal. If this is not possible, oral administration of honey in the first 12 hours (10 mL every ten minutes in children older than 1 year) or sucralfate (10 mL every 10 minutes, maximum 3 doses) is recommended to limit tissue necrosis and prevent subsequent perforation, without delaying its emergent endoscopic removal [20].

During endoscopy, if no local perforations are seen, the battery site should be irrigated with 50–150 ml 0.25% acetic acid, and additional endoscopic airway evaluation should be considered in cases of extensive mucosal necrosis. After endoscopic removal, an examination of the esophageal mucosa should be performed to anticipate potential complications [23].

All cases where the diagnosis is delayed, or there is clinical suspicion of perforation, mediastinitis, or sepsis, where swallowing difficulties are observed, must be treated with the greatest caution and monitored for several days, until complications are ruled out.

Most complications occur more than 30 days after initial ingestion, so careful monitoring of these patients is important. The onset of symptoms, at any time, requires urgent reassessment and, most likely, surgical intervention [24].

In cases where the battery was successfully extracted shortly after ingestion, the initial injuries may not be very severe, so that endoscopy should be repeated at least 48–72 hours after the first evaluation [25]. Long-term follow-up after endoscopic removal depends on the presence and extent of esophageal injury.

Batteries that have passed into the stomach or beyond do not rule out esophageal injury, but this must be excluded. In these patients, a second-look examination may be considered within 2-4 days after gastric removal.

Urgent endoscopic removal within the first 24 hours is necessary for multiple magnets or long objects in the stomach and for sharp objects in the esophagus, stomach, or duodenum. Sharp foreign bodies should be also endoscopically removed without delay, using protective devices (cap, latex protection, or outer tube), in order to reduce the risk of retrograde mucosal injury and perforation during extraction [26].

Superabsorbent object ingestion management is difficult because they are radiolucent and pass quickly through the proximal GI tract, so that CT and ultrasound are important diagnostic tools. Asymptomatic patients with recent ingestion may be managed conservatively under close monitoring. Endoscopy may be prioritized for superabsorbent objects with an initial diameter >3.5 mm [27]. Favorable outcomes have also been reported by crushing the beads during laparotomy and advancing them into the colon for enema-assisted expulsion [28].

For asymptomatic, non-hazardous objects that have reached the small intestine, endoscopic removal is not an emergency and can be performed within the first 72 hours. Large coins or those that do not pass through the stomach within 3 days must be endoscopically removed [29].

Smaller trichobezoars can be extracted endoscopically after fragmentation, while larger ones often require surgical intervention [30]. A psychological evaluation and, if necessary, pediatric psychiatric therapy should always be performed to prevent recurrence [31].

Conservative treatment with serial imaging and observation may be indicated for asymptomatic, previously healthy children who have ingested small, non-hazardous objects, because most often they pass spontaneously. Children who have swallowed one or multiple magnets and are asymptomatic can be monitored by serial imaging at 24-hour intervals [16].

In healthy patients, small, inert objects near the gastroesophageal junction typically pass into the stomach within a few hours and move through the intestines without complications. However, the onset of symptoms is an indication for urgent intervention: either endoscopic removal of gastric foreign bodies or surgical extraction in case of intestinal obstructions.

Endoscopic extraction typically requires general anesthesia with orotracheal intubation. In cases requiring urgent extraction, pre-anesthetic fasting (NPO rules) is not required, as postponing the procedure can lead to serious and potentially life-threatening consequences. In these situations, airway protection is ensured by rapid sequence induction.

6. Complications

Although over 80% of foreign bodies that enter the esophagus pass spontaneously into the stomach without complications, the rest become lodged in the esophagus. Esophageal obstruction carries the highest risk of complications (25% higher than in other parts of the digestive tract), which can be life-threatening given its proximity to vital organs. Risk factors include esophageal strictures (congenital or acquired), prior esophageal atresia repair, eosinophilic esophagitis, motility disorders, achalasia, esophageal diverticulum, extrinsic compression by tumors, and psychiatric disorders [7].

Partial or complete obstruction of the esophagus is the most common complication, but foreign bodies can also become lodged in any other segment of the digestive tract. Some of them may erode the GI tract walls, causing perforation and subsequent migration outside the lumen. In patients with pre-existing anatomical or functional abnormalities, the risk of complications is increased [32].

Complications following battery ingestion include tracheoesophageal strictures and fistulas, mediastinitis, vocal cord paralysis, or spondylodiscitis. Button batteries with a diameter of more than 20mm can lodge in the upper esophageal sphincter with subsequent perforation and fistulization in the major blood vessels or in the trachea, which can be fatal. Perforations are typically diagnosed within 2 days (rarely within the first 12 hours), but fistulas may appear up to 4 weeks after removal. Deaths can occur from fistulas in major blood vessels like the aorta, subclavian artery, or thyroid arteries, while aorto-esophageal fistulas carry a particularly high mortality rate [33].

It is important to highlight that even after the button battery has been removed, the esophageal lesions may continue to develop for several days or weeks; necrosis of the esophagus and surrounding tissue is an ongoing process that can lead to fistula formation, with further serious complications.

In cases of important esophageal mucosa injury, a nasogastric tube must be inserted endoscopically to maintain the patency of the lumen, and the patient must not be fed orally until perforations or other complications are excluded.

If significant bleeding occurs during or after the impaction of a button-cell battery in the upper esophagus, fistulas to large blood vessels, such as the aorta, subclavian artery, or thyroid artery, must be considered, and immediate coordination of all available specialty departments (including cardiac and thoracic surgery, interventional radiology, and critical care) is required to establish an urgent multidisciplinary therapeutic strategy.

In all cases with severe complications, such as aorto-esophageal fistula, respiratory symptoms secondary to tracheo-esophageal fistula, tracheal stenosis, or sepsis from mediastinitis, complex anesthetic management is required, with invasive monitoring and subsequent follow-up in the intensive care unit [34].

According to NASPGHAN guidelines, MRI scan has to be performed 3–5 days after the ingestion incident, followed by scans every 5–7 days, until the inflammation of the tissue surrounding the esophagus has subsided, with the expected significant risk of a fistula forming into large blood vessels expected to resolve after 21 days. More recent data reveal that serial MRIs do not predict the development of severe complications. In one case with battery ingestion, a total of 3 MRI scans were performed on days 1, 5, and 11 after its removal, documenting a sustained improvement in mediastinal damage; nevertheless, an aortoesophageal fistula developed after 25 days [35].

Button batteries that have passed through the esophagus should be monitored by X-ray every 3 to 4 days. If there is suspicion of blockage in the small intestine, surgical intervention is indicated, as even at this stage, if they remain lodged, they can cause mucosal damage and complications.

Besides button batteries, high-powered neodymium magnets are among the most dangerous objects children can swallow, causing ischemia, necrosis, perforation, fistula with consequent sepsis, obstruction, or even death [36].

Foreign bodies with a sharp edge are associated with an increased risk of impactation and perforation, followed by extraluminal migration, abscess, peritonitis, liver, bladder, heart, or lung penetration, carotid artery lesion, aortoesophageal fistula, and death.

Coins can cause significant morbidity and mortality when retained in the GI tract for long time periods, such as esophageal impaction, tracheoesophageal fistulas, esophageal perforation, esophageal ulceration, peri-esophagitis, esophageal or tracheal stenosis, mediastinitis, pneumothorax, pyothorax, and unilateral vocal cord paralysis [37].

7. Conclusions

Although foreign body ingestion in children generally does not result in complications, it can sometimes lead to serious, even fatal outcomes.

Therefore, suspected diagnosis in cases with nonspecific symptoms, even in the absence of medical history, together with appropriate assessment and prompt treatment, is important in preventing severe consequences. It is also important to know which patients require hospitalization and monitoring, but above all, to accurately identify the situations that require immediate medical intervention.

Most foreign body ingestions pass spontaneously through the GI tract, but it must be kept in mind that there are high-risk foreign body ingestions: button batteries lodged in the esophagus, concomitant ingestion of magnets and batteries, magnets and metal objects, multiple magnets, sharp objects, expandable foreign bodies (superabsorbent polymers, and all cases with complete GI obstruction.

Prevention plays a crucial role; therefore, parents and caregivers need to be made aware that dangerous objects should be kept away from children’s reach.