INTRODUCTION — Tracheobronchial foreign body aspiration (FBA) is a potentially life-threatening event because it can block respiration by obstructing the airway, thereby impairing oxygenation and ventilation. FBA in children may be suspected on the basis of a choking episode if such an episode is witnessed by an adult or remembered by the child. In contrast, the clinical presentation of unwitnessed FBA may be subtle, and diagnosis requires careful review of the history, clinical assessment, and the judicious use of radiography and bronchoscopy.

Aspiration of foreign bodies in children will be reviewed here. A discussion of FBA in adults and older children is presented separately. (See "Airway foreign bodies in adults".)

EPIDEMIOLOGY — Foreign body aspiration (FBA) is a common cause of mortality and morbidity in children, especially in those younger than two years of age. During 2000, ingestion or aspiration of an FB was responsible for more than 17,000 emergency department visits in children younger than 14 years in the United States [1].

Before the 20^th century, aspiration of an FB had a 24 percent mortality rate. With the development of modern bronchoscopy techniques, mortality has fallen dramatically [2]. Nonetheless, in the United States, FBA was responsible for approximately 4800 deaths in 2013, or approximately 1 death per 100,000 children 0 to 4 years old [3]. Death caused by suffocation following FBA is the fifth most common cause of unintentional-injury mortality in the United States and the leading cause of unintentional-injury mortality in children younger than one year [4]. In 2016, there were 118 deaths due to suffocation in the one- to four-year-old age group, and 49 of these (41 percent) were due to FBA [4]. In a review of the Nationwide Inpatient Sample from 2009 to 2011 of all cases with pediatric FBA in the United States, the combined rate of death or anoxic brain injury was around 4 percent and the annual associated inpatient cost was close to $13 million [5].

Approximately 80 percent of pediatric FBA episodes occur in children younger than three years, with the peak incidence between one and two years of age [6-13]. At this age, most children are able to stand and be mobile independently and are apt to explore their world via the oral route. They also have the fine motor skills to put a small object into their mouths, but they do not yet have molars to chew food adequately and may have uncoordinated or immature swallowing mechanisms [14]. Additional predisposing factors to FBA in this age group include access to improper foods or small objects, activity while eating, and older siblings (who may place food or objects into the mouths of infants or toddlers). Young children are also particularly vulnerable to FBA because of the smaller diameter of their airway, which is prone to obstruction [15]. In older children and adults, neurologic disorders [16], loss of consciousness, and alcohol or sedative abuse predispose to FBA [17]. Most case series in children report a male predominance, with a sex ratio ranging from 1.5:1 to 2.4:1 [6,11,18]. (See "Airway foreign bodies in adults".)

Commonly aspirated FBs in children include peanuts (36 to 55 percent of all FBs in Western society), other nuts, seeds (particularly watermelon seeds in Middle Eastern countries), popcorn, food particles, hardware, and pieces of toys (picture 1A-B) [8-10,12,13]. Food items are the most common items aspirated by infants and toddlers, whereas nonfood items (eg, coins, paper clips, pins, pen caps) are more commonly aspirated by older children [19-22]. Jewelry, followed by coins, are the most common consumer products aspirated, at 30 and 10 percent, respectively, in one study [23]. Toy balloons or similar objects (eg, inflated gloves or condoms) are the most common objects involved in fatal childhood FBA [15]; balls, marbles, and other toys also are commonly involved. Inert foreign bodies remain in place longer and cause less complications [14]. Factors that make FBs more dangerous include roundness (round objects are most likely to cause complete airway obstruction and asphyxiation); failure to break apart easily; compressibility; and smooth, slippery surface [15]. The effects of pill aspiration depend on the properties of the medication. Certain medications such as iron or potassium may dissolve in the airways and cause intense inflammation and eventually stenosis, so early diagnosis and timely extraction is important to minimize long-term consequences [24,25].

The majority of aspirated FBs in children are located in the bronchi [6,10,26]. Laryngeal and tracheal FBs are less common. In a large case series of FBA aspirations in children, the sites of the FB were as follows [6]:

●Larynx – 3 percent

●Trachea/carina – 13 percent

●Right lung – 60 percent (52 percent in the main bronchus, 6 percent in the lower lobe bronchus, and <1 percent in the middle lobe bronchus)

●Left lung – 23 percent (18 percent in the main bronchus and 5 percent in the lower bronchus)

●Bilateral – 2 percent

Although most aspirated FBs are located in the bronchi, large, bulky FBs (eg, food) or those with sharp, irregular edges may become lodged in the larynx [10,27]. This is particularly common in infants younger than one year. Tracheal narrowing or weak respiratory effort may predispose to tracheal FB [10]. Compared with bronchial FBs, laryngotracheal FBs are associated with increased morbidity and mortality [27,28].

PRESENTATION — The presentation of foreign body aspiration (FBA) depends to some extent upon degree of airway blockage and the location of the object, as well as the age of the child, type of object aspirated (particularly, its size and composition), and elapsed time since the event (which often depends on whether the event was witnessed). Unfortunately, delayed presentation is common: Presentation and diagnosis within 24 hours of aspiration occurs in only 50 to 60 percent of cases [10,14]. To avoid delayed diagnosis and associated morbidity, a high index of suspicion for FBA is warranted.

Signs and symptoms — Children who present with severe respiratory distress, cyanosis, and altered mental status have a true medical emergency that demands prompt recognition, life support, and rigid bronchoscopic removal of the FB. (See 'Life-threatening foreign body aspiration' below.)

More commonly, children with FBA present with partial airway obstruction. The most common symptom is cough, followed by tachypnea and stridor, often with focal monophonic wheezing or decreased air entry. Regional variation in aeration is an important clue to the diagnosis and is often detected only if the clinician completes a thorough examination when the child is quiet and with minimal ambient noise. Nonspecific findings of cough and generalized wheezing are often present. The classic triad of wheeze, cough, and diminished breath sounds [29] is not universally present [10,29]. In a review of 135 cases of airway FB in children, the classic triad was present in only 57 percent [10]. The presence of the triad has high specificity (96 to 98 percent) for the diagnosis of FBA, but the sensitivity is low (27 to 43 percent) [30].

The signs and symptoms of FBA vary according to the location of the FB [31,32]:

●Laryngotracheal – Laryngotracheal FBs are uncommon (5 to 17 percent of FBs) but are particularly likely to be life-threatening. Symptoms include stridor, wheeze, salivation, dyspnea, and sometimes voice changes. FBs in this location are most likely to present with acute respiratory distress, which must be addressed promptly [27,28]. Laryngeal FBs or large penetrating FBs with sharp edges also may cause symptoms related to the esophagus. (See 'Life-threatening foreign body aspiration' below.)

●Large bronchi – The usual symptoms are coughing and wheezing. Hemoptysis, dyspnea, choking, shortness of breath, respiratory distress, decreased breath sounds, fever, and cyanosis may also occur [6,7,33]. The right main bronchus (image 1) is the most common location, followed by left bronchus (image 2) and bilateral bronchi. Compared with adults, children have less predilection for the right versus left main bronchus because the airway in children is not fully developed and there are few significant anatomical differences between left and right bronchial tree [14].

●Lower airways – Children with these FBs may have little acute distress after the initial choking episode (algorithm 1).

History of choking — A witnessed episode of choking, defined as the sudden onset of cough and/or dyspnea and/or cyanosis in a previously healthy child, has a sensitivity of 76 to 92 percent for the diagnosis of FBA (table 1) [6,10,11,34-36]. The choking phase occurs immediately after the episode and lasts a few seconds to several minutes. The acute episode usually is self-limited and may be followed by a symptom-free period, which must not be misinterpreted as a sign of resolution, since it may delay the diagnosis [20]. In other cases, children continue to have respiratory distress, wheezing, and/or persistent coughing (algorithm 1).

Although highly suggestive of FBA, a history of choking may not be recalled during initial evaluation; detailed and repeated questioning of all caregivers may be necessary to stimulate recall of the choking episode. In one review of 200 cases of FBA, 19 percent presented more than one month after aspiration, even though a history of choking was present in 88 percent [35].

Delayed diagnosis — Patients who present days or weeks after the aspiration often develop symptoms due to complications related to the presence of the FB, such as infection and inflammation of the airway. Thus, they may present with fever and other signs and symptoms of pneumonia. In the absence of a history of choking, FBA may not be suspected. These patients with occult FBA may improve with antibiotic therapy. However, the infiltrate on chest radiograph usually does not resolve and recurrence of pneumonia is common.

One reason for delay in diagnosis is that children with lower airway FBs may present with subtle or nonspecific symptoms [37]. As a result, they may come to medical attention only when they develop dyspnea, wheezing, chronic cough, or recurrent pneumonia (algorithm 1) [35]. Other factors contributing to diagnostic delay include unwitnessed aspiration; decision by the parents or clinician not to pursue evaluation once the acute choking episode has resolved; and misinterpretation of symptoms as evidence supporting the diagnosis of de novo pneumonia, asthma or asthma exacerbation, or bronchiolitis [10,37-39]. (See "Evaluation of wheezing in infants and children" and "Approach to chronic cough in children".)

EVALUATION — The sequence of evaluation and management depends on the clinical characteristics of the patient at presentation and during the initial work-up. Patients with complete or impending airway obstruction move immediately to intervention, whereas stable patients with suspected foreign body aspiration (FBA) undergo further evaluation, as described below.

Life-threatening foreign body aspiration — If a child presents with complete airway obstruction (ie, is unable to speak or cough), dislodgement using back blows and chest compressions in infants, and the Heimlich maneuver in older children, should be attempted. In contrast, these interventions should be avoided in children who are able to speak or cough since they may convert a partial to a complete obstruction [10]. For the same reason, "blind" sweeping of the mouth should be avoided.

The recommendations of the American Heart Association regarding interventions for choking represent the standard in acute life-threatening events (algorithm 2) [40]. When the obstructing FB is below the larynx and does not move with the American Heart Association-recommended procedures, intubation may permit some ventilation until rigid bronchoscopy is possible. The administration of oxygen and other life-sustaining care should be provided until bronchoscopy can be performed. Occasionally, extracorporeal oxygen support (ECMO) has been used before and/or after FB removal to stabilize a gravely ill, hypoxemic patient [41]. (See "Emergency evaluation of acute upper airway obstruction in children" and "Basic airway management in children".)

Suspected foreign body aspiration — All children with suspected FBA who are stable should undergo a focused history and physical examination, followed by plain radiography of the chest (see 'Imaging' below). The caregivers should be specifically asked about a history of a choking episode in the hours or days prior to symptom onset. A history of choking, when specifically sought, is found in approximately 80 to 90 percent of confirmed cases (see 'History of choking' above). The physical examination should evaluate for wheezing, stridor, and regional variation in breath sounds, which may be subtle and difficult to detect in a young, uncooperative child.

Level of suspicion — The extent of the evaluation depends on the clinical suspicion for FBA (algorithm 3).

●A moderate or high suspicion of FBA is suggested by any of the following:

•Witnessed FBA, regardless of symptoms.

•History of choking, with any subsequent symptoms or suspicious characteristics on imaging.

•Young child with suggestive symptoms without other explanation, especially if there are suspicious characteristics on imaging. Suspicious symptoms include cyanotic spells, dyspnea, stridor, sudden onset of cough or wheezing (often focal and monophonic), and/or unilaterally diminished breath sounds.

The tracheobronchial tree should be examined in all cases with a moderate or high suspicion of FBA, using rigid bronchoscopy (or, in some cases, computed tomography [CT]). On occasion, the adjunctive use of a flexible bronchoscope may be helpful. Normal chest radiographs are not sufficient to rule out FBA, primarily because most FBs are radiolucent. The morbidity and mortality may be increased if bronchoscopic evaluation is delayed [10,11,38,42,43]. Therefore, the clinical suspicion of FBA is the most important step in diagnosis. (See 'Bronchoscopy' below.)

●A low suspicion of FBA is appropriate if none of the above features are present. In this case, normal results of plain radiographs are sufficient to provisionally exclude FBA. However, such patients should be observed, with follow-up in two to three days and further evaluation (eg, bronchoscopy) if symptoms persist or progress. (See 'Imaging' below.)

Imaging — For patients with suspected FBA who are asymptomatic, or symptomatic but stable, the first step in the evaluation is to perform plain radiography of the chest. Subsequent steps depend on the degree of clinical suspicion for FBA and may include CT or other modalities (algorithm 3).

Conventional radiography — Conventional ("plain") radiographic evaluation of the chest may or may not be helpful in establishing the diagnosis of FBA, depending upon whether the object is radiopaque and whether and to what degree airway obstruction is present. The diagnosis of FBA is easily established with conventional radiographs when the object is radiopaque (approximately 10 percent of FBs) (image 3). However, most objects aspirated by children are radiolucent (eg, nuts, food particles) [44] and are not detected with conventional radiographs, unless aspiration is accompanied by airway obstruction or other complications [6,44-46]. As a result, normal findings on radiography do not rule out FBA, and the clinical history is the main determinant of whether to perform a bronchoscopy [47].

In children with lower airway FBA, the most common radiographic findings in lower airway FBA are [18,31,32,48]:

●Hyperinflated lung (lucency distal to the obstruction) – This is caused by partial airway obstruction with air trapping, such that air passes with inspiration but not with exhalation (image 4A-B).

●Atelectasis – This is usually caused by complete obstruction of an airway since air is resorbed from the distal alveoli over time. (See "Atelectasis in children".)

●Mediastinal shift – The mediastinum tends to shift away from the lung field containing the FB.

●Pneumonia – Infection often develops distal to an obstructed airway. Therefore, a consolidated infiltrate is also a possible finding. (See "Community-acquired pneumonia in children: Clinical features and diagnosis", section on 'Radiologic evaluation'.)

Pulmonary abscesses and bronchiectasis are late manifestations of a retained airway FB [49,50].

The chest radiograph is normal in at least 30 percent of cases [6,18,36]. The sensitivity of chest radiography has been reported to be 68 to 76 percent and the specificity 45 to 67 percent when evaluating for FBs in the airway [51]. Ideally, both inspiratory and expiratory radiographs should be obtained, if this is possible, because this may increase the sensitivity for detecting a radiolucent FB. In young children in whom it is difficult to obtain expiratory radiographs (either because they are tachypneic or because they cannot cooperate), left decubitus films may simulate expiratory radiographs. However, two retrospective studies suggested that these films did not add diagnostic value, at least as routinely performed [52,53].

If a laryngotracheal FB is suspected based on symptoms (stridor, wheeze, dyspnea, and sometimes hoarseness), a neck radiograph should be performed. These should include posteroanterior and lateral views, with the arms and shoulders positioned inferiorly and posteriorly to optimize the image of the larynx and trachea. Even if the FB is radiolucent, these films may suggest the diagnosis if they show a subglottic density or swelling [28].

Advanced imaging — CT or (to a lesser extent) magnetic resonance imaging (MRI) are possible diagnostic options for patients who are asymptomatic or symptomatic but stable, who have normal or inconclusive conventional radiographs but an ongoing clinical suspicion of FBA. However, this imaging is only helpful if the provider judges that negative imaging would be sufficient to preclude bronchoscopy [54,55]. In most cases, such patients proceed directly to bronchoscopy without these studies.

●CT – CT is potentially a valuable tool in diagnosing FBA, with a sensitivity of almost 100 percent and specificity of 66.7 to 100 percent [56]. Unlike conventional radiography, CT usually can detect radiolucent foreign bodies such as vegetables. It is available in most institutions with high-resolution, multiplanar, three-dimensional, and other image reconstruction capabilities. CT can indicate the exact location of the FB and detect associated complications (image 2 and image 1) [14]. The main disadvantage of any CT technique is the exposure to ionizing radiation and delay in proceeding to therapeutic bronchoscopy. Where low-dose CT protocols are available, early use of this modality may be appropriate for many patients and may reduce the need for bronchoscopy [56,57].

●MRI – MRI is a good tool for FB imaging because of its multiplanar and tissue differentiation properties. MRI is particularly useful for identifying aspirated peanuts due to their high fat content, which provides high contrast differentiation. However, MRI is rarely used for the evaluation of FBA in young children due to the need for sedation [14].

Fluoroscopy — Fluoroscopy may be used in selected patients as an adjunct to conventional radiography to help identify and localize a radiolucent FB. Findings suggesting FBA include abnormal mediastinal shift with decreased excursion of the diaphragm, representing air trapping. Tracheal and bronchial narrowing demonstrated via digital subtraction fluoroscopy suggest the presence of an adjacent radiolucent FB. However, findings are only positive in approximately 50 percent of pediatric cases [14].

Bronchoscopy — The tracheobronchial tree should be examined in all cases with a moderate or high suspicion of FBA, typically using rigid bronchoscopy so that the object can be safely removed. (See 'Foreign body removal' below.)

Flexible rather than rigid bronchoscopy may be used for diagnostic purposes in cases in which the diagnosis is unclear or if the FBA is known but the location of the object is unclear [58]. In this case, most centers also arrange to have rigid bronchoscopy available on standby because this is the preferred approach for FB removal. In some centers, flexible bronchoscopy is also used for FB removal, as discussed below. (See 'Foreign body removal' below.)

MANAGEMENT — Once the diagnosis of foreign body aspiration (FBA) has been established by imaging and/or flexible bronchoscopy, the object should be removed as quickly as possible. Laryngeal or tracheal FBs require particularly urgent management.

Foreign body removal — If FBA is known to have occurred or is strongly suspected, rigid bronchoscopy is the procedure of choice to identify and remove the object [31,58,59]. Rigid bronchoscopy permits control of the airway, good visualization, manipulation of the object with a wide variety of forceps, and ready management of mucosal hemorrhage [22,60-62]. Bronchoscopy is successful in removing the FB in approximately 95 percent of cases, with a complication rate of less than 1 percent [6,63,64]. Thoracotomy is occasionally indicated in the rare cases in which FBs are visualized but cannot be removed through a rigid bronchoscope.

FB extraction should be performed by an experienced operator to minimize the risk of complications. Unsuccessful attempts to remove the FB may push it into a distal position, making it more difficult to retrieve. In addition, dislodgement of all or part of the FB, or a fragment of the FB, into the mainstem bronchus of the contralateral lung are potentially lethal complications if the originally involved bronchus remains obstructed by inflammation or a residual FB [65]. Major complications of FB extraction include pneumothorax, hemorrhage, and respiratory arrest, but they occur rarely.

Alternatively, flexible (rather than rigid) bronchoscopy is used to remove the FB in some centers with high levels of experience in this technique. [32,61,66,67]. This technique usually is limited to older adolescents or young adults and uses a removal tool using biopsy, grasping forceps, or wire baskets, with varying success rates [32,68,69]. Potential advantages of using flexible bronchoscopy for FB extraction are avoidance of general anesthesia and the ability to reach subsegmental bronchi. In a large case series, the FB was successfully removed by flexible bronchoscopy in 91 percent of patients [32]. The main disadvantage of flexible bronchoscopy for FB removal is the risk of dislodging the FB and further compromising the airway. Because of these concerns, the American Thoracic Society states, "In general, rigid instruments are superior for detailed anatomic assessment of the larynx and cervical trachea and for operative manipulation, principally foreign body extraction" [62]. Flexible bronchoscopy is also used by most centers for management of FBA in adults. (See "Airway foreign bodies in adults", section on 'Foreign body removal'.)

If there is a suspicion for multiple small FBs or fragments, we recommend performing a complete flexible bronchoscopy after FB removal to evaluate the entire tracheobronchial tree [35,70]. If the FB has been retained long enough for an infection to occur, a Gram stain and culture should be obtained through the bronchoscope to guide postoperative antibiotic management. If clinical symptoms, signs, or abnormal radiographs persist after the FB removal and treatment of infection, repeat bronchoscopic examination is warranted to look for a second, previously unseen FB.

Occasionally, an FB that has been retained for several weeks will cause such intense airway inflammation and infection that it cannot be removed. In such cases, antibiotics should be administered, guided by Gram stain and cultures obtained at bronchoscopy. In addition, a three- to seven-day course of systemic corticosteroids (methylprednisolone [or equivalent] 1 to 2 mg/kg per day either by mouth or intravenously) may help reduce inflammation [71], although the use of corticosteroids has not been objectively studied in this situation. After appropriate antibiotic and corticosteroid therapy, the FB may be removable at a second rigid bronchoscopy. Corticosteroid therapy may result in dislodgement of the FB, followed by unwitnessed expectoration and swallowing; therefore, these patients should have a repeat physical examination and radiographic evaluation to determine if the FB is still present before bronchoscopy is repeated. Thoracotomy may be required if the second procedure is unsuccessful.

Complications — When FBA is diagnosed soon after the event, there is usually little damage to the airway or lung parenchyma. Complications such as atelectasis, postobstructive pneumonia, or bronchiectasis may develop if the diagnosis is delayed. As examples, studies have reported complication rates of 64, 70, and >95 percent if diagnosis is delayed by 4 to 7 days, 15 to 30 days, or greater than 30 days, respectively [37,42,72,73]. An FB that causes chronic or recurrent distal infection may lead to bronchiectasis in 25 percent of cases if the FB is present for 30 days or more [35,49,50,74,75]. This complication should be treated after the FB is removed. Cultures obtained during bronchoscopy guide the initial antibiotic choice in treating infected areas of bronchiectasis. Failure to promptly diagnose the FBA may also cause complications from the use of non-indicated treatments, such as steroids, antibiotics, or bronchodilators [76,77].

PREVENTION — As a general rule, primary passive intervention strategies to reduce the risk of foreign body aspiration (FBA), such as legislation that eliminates choking hazards from the market, are more effective than active intervention strategies (strategies that require constant parental supervision) [78]. (See "Pediatric injury prevention: Epidemiology, history, and application", section on 'Principles of injury prevention and control'.)

Legislation — In the United States, legislative efforts to prevent FBA in children were initiated in 1927 with passage of the Federal Caustic Act, which prohibited misbranded shipments of dangerous caustic or corrosive substances in interstate or foreign commerce. This act was the first child-environmental safety act, and its passage was due largely to the efforts of the pioneering laryngologist, Chevalier Jackson [75].

Additional legislative efforts to prevent FBA in children include various portions of the Federal Hazardous Substances Act (FHSA, 1979). The Consumer Products Safety Act banned from interstate commerce any toy or other article intended for use by children younger than three years old that is potentially hazardous for choking, aspiration, or ingestion because of small parts [19]. "Small parts" are objects that fit into the Small Parts Test Fixture (SPTF), a cylinder with a diameter of 3.17 cm and a depth between 2.54 and 5.71 cm [79,80]. Similar standards are included in the European Toy Safety Directive of 2009 [81,82] and the Canada Consumer Product Safety Act of 2010 [83].

Use of the SPTF has not been universally successful in preventing choking deaths [19,84,85]. In a review of the characteristics of FBs involved in choking episodes, objects that were spherical or had spherical parts caused asphyxiation even when they met SPTF standards [19]. Based upon the sizes and shapes of the FBs in this study, the authors suggest that spherical objects should be at least 4.44 cm in diameter and linear objects should be at least 7.62 cm in length to prevent fatal choking [19].

Since 1995, packaging for toys with small parts, balls with diameters <4.44 cm, and marbles must contain a label stating that the item contains small parts, is a choking hazard, and should not be used by children younger than three years. In addition, packages of balloons must contain a label stating that balloons are a choking hazard, that children younger than eight years can choke or suffocate on uninflated or broken balloons, and that adult supervision is required [86].

The Consumer Product Safety Improvement Act of 2008 [87] amended the FHSA to require choking hazard warnings to be displayed on or adjacent to product advertisements on websites, catalogs, or other printed materials that provide direct means for purchase of a product for which a warning is required under the FHSA [15].

Of note, food items, which are the most commonly aspirated FB in infants and toddlers, are not regulated by the FHSA and are not subject to SPTF testing. Actions by the federal government to prevent choking on food by young children should include surveillance, cautionary food labeling, recalls when necessary, and public education. Legislation has been proposed but never enacted [15].

The Consumer Product Safety Commission (CPSC) maintains information on hazardous toys; product defects can be reported to the CPSC on their website or to their telephone hotline (800-638-2772).

Education — Education is another strategy to prevent FBA in children. Although educational efforts may change safety-related knowledge and behavior, direct evidence that educational counseling results in lower injury rates is lacking. Nonetheless, the American Academy of Pediatrics recommends that anticipatory guidance to prevent choking/FBA be provided to caregivers beginning when the child is six months of age [15,88]. At this age, children begin to develop the fine motor dexterity to pick up small objects and put them into their mouths. Important aspects of anticipatory guidance include the following [15,21,89]:

●Marbles, small rubber balls, and latex balloons should be mentioned specifically since aspiration of these items may be fatal. Latex balloons are the leading non-food cause of fatal choking episodes among children [15].

●Hard and/or round foods should not be offered to children younger than four years of age; these include (but are not limited to) hard candy and other candies, peanuts, meat chunks, hot dogs, grapes, raisins, apple chunks, nuts, popcorn, watermelon seeds, and raw carrots [12,13]. Among these items, peanuts are the most common single food causing injury and hot dogs and candy are the most common causes of fatal injury [13].

●Infants should be fed solid food only by adults and only when the infant is sitting upright; all meals for young children should be supervised by an adult.

●Children should be taught to chew their food well; shouting, talking, playing, running, crying, and laughing while eating should be discouraged.

●Chewable medications should be given only after the age of three years (when molars are present).

●Coins and other small items should not be given to young children as rewards.

●The practice of using the mouth to hold school supplies or other small objects should be discouraged.

●Avoid toys with small parts, and keep other small household items out of the reach of infants and young children.

●Follow the age recommendations on toy packages.

●Be aware of the actions of older children. They may give dangerous objects to younger siblings.

●Parents, teachers, child care providers, and others who care for children should be encouraged to take a course in basic life support and choking first aid.

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Airway foreign bodies in children".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Basics topics (see "Patient education: Starting solid foods during infancy (Beyond the Basics)" and "Patient education: Cough in children (The Basics)" and "Patient education: Coughing up blood (The Basics)" and "Patient education: Bronchiectasis in children (The Basics)")

●Beyond the basics topics (see "Patient education: Starting solid foods during infancy (Beyond the Basics)")

SUMMARY

●Foreign body aspiration (FBA) should be suspected in children who have sudden onset of lower respiratory symptoms or those who do not respond to standard management of other suspected etiologies such as pneumonia, asthma, or croup. The risk is highest in children between one and three years of age. (See 'Presentation' above.)

●A history of choking is highly suggestive of FBA, even if it occurred days or weeks before presentation. The episode may be immediately followed by respiratory symptoms or there may be a symptom-free period, which must not be misinterpreted as a sign of resolution, since it may delay the diagnosis. The absence of choking history does not rule out FBA, since choking events may be unwitnessed or unrecalled. (See 'History of choking' above.)

●The presence of asphyxia indicates the need for immediate resuscitation and examination of the airway (algorithm 2). (See 'Life-threatening foreign body aspiration' above.)

●For patients with suspected FBA who are asymptomatic or symptomatic but stable, the first step in the evaluation is to perform plain radiography of the chest (algorithm 3). Ideally, both inspiratory and expiratory radiographs should be obtained, if this is possible, because this may increase the sensitivity for detecting a radiolucent FB. Subsequent steps depend on the degree of clinical suspicion for FBA and may include computed tomography (CT) or bronchoscopy. Normal radiographic studies do not exclude the presence of an aspirated FB. (See 'Imaging' above.)

•A moderate or high suspicion of FBA is appropriate for all children with a witnessed FBA (regardless of symptoms), as well as for young children with suspicious respiratory symptoms or characteristics on imaging, especially if there is a history of choking. Suspicious symptoms include cyanotic spells, dyspnea, stridor, sudden onset of cough or wheezing (often focal and monophonic), and/or unilaterally diminished breath sounds. (See 'Level of suspicion' above.)

•A low suspicion of FBA is appropriate if none of the above features are present. In this case, normal results of plain radiographs are sufficient to exclude radiopaque FBA and lessen (but not completely eliminate) the concern for a radiolucent FBA. However, such patients should be observed, with follow-up in two to three days and further evaluation (eg, bronchoscopy) if symptoms persist or progress.

●Stable patients with a high clinical suspicion of FBA usually should proceed to bronchoscopy, even if the plain radiographs are normal or inconclusive. Alternatively, CT can be performed first to help clarify the diagnosis, if the provider judges that negative imaging would be sufficient to preclude bronchoscopy. Flexible rather than rigid bronchoscopy may be used for diagnostic purposes in cases in which the diagnosis is unclear or if the FBA is known but the location of the object is unclear. (See 'Bronchoscopy' above.)

●We suggest rigid rather than flexible bronchoscopy for removal of most aspirated FBs in children (Grade 2C); this procedure should be performed by an experienced operator. Flexible bronchoscopy is also used to remove the FB in some centers with high levels of experience in this technique. (See 'Suspected foreign body aspiration' above and 'Foreign body removal' above.)

●Prevention of pediatric FBA is possible through legislation, caregiver education, and continued product safety vigilance. (See 'Prevention' above.)