A practical guide for resident doctors in the emergency department, focusing on recognising and managing paediatric foreign body inhalation and ingestion — where early decision-making really matters.

Foreign body inhalation and ingestion are common paediatric presentations, particularly in children aged 6 months to 3 years, reflecting developmental behaviours such as mouthing objects and incomplete chewing.

While the majority of ingestions are benign and self-limiting, foreign body aspiration and certain high-risk ingestions (e.g. button batteries, magnets) can rapidly become life-threatening. The challenge in the emergency department (ED) lies in early recognition, risk stratification and timely escalation.

This article provides a practical, ED-focused approach to both inhalation and ingestion, with an emphasis on red flags, decision-making, and common pitfalls.

Foreign Body Inhalation (Aspiration)

Why it matters

Foreign body aspiration is a potentially fatal but often subtle diagnosis. Delays in recognition can lead to complications such as:

• Airway obstruction
• Recurrent pneumonia
• Bronchiectasis

The peak incidence is in children under 3 years, with nuts (particularly peanuts), popcorn, fruit, seeds, and small toys being the most common AFB (aspirated foreign body) culprits. AFBs are most likely to lodge in the right main bronchus due to anatomical alignment.

Airway obstruction may initially present with choking, coughing and distress, but can progress quickly to an ineffective cough and respiratory arrest. In these cases, follow local resuscitation guidance (back blows, abdominal or chest thrusts depending on the child’s age, CPR if unresponsive). The Resuscitation UK Council website has the most up-to-date national guidelines for management of the choking child.

History

A clear choking episode reported by the parent is helpful – but do not rely on this.

Key features:

• Sudden onset coughing, choking or gagging – may or may not be intermittent
• “Strange” throat clearing noises
• Episode occurring during, or shortly after eating or playing
• Persistent cough or wheeze following an event
• Cyanosis during the choking episode

Note that symptoms may present days to weeks after the inhalation. Delayed presentation is common, with only 50-60% of cases presenting within 24hrs. Up to 40% of cases are unwitnessed.

Examination

Findings may include:

• Unilateral reduced air entry
• Monophonic, localised wheeze
• Stridor (upper airway obstruction)
• Crackles (late finding)

Note that the examination may be completely normal, as may the observations and PEWS score.

Red flags warranting urgent senior input

• Stridor
• Severe respiratory distress with increased work of breathing
• Cyanosis or hypoxia
• Silent chest

Investigations

First line: Chest X-ray (CXR) with inspiratory and expiratory views. Possible findings include:

• Hyperinflation (ball-valve effect – air cannot get past the AFB)
• Unilateral atelectasis and/or emphysema
• Mediastinal shift
• Radio-opaque object (if metallic)

A normal CXR does NOT exclude foreign body aspiration

Why inspiratory + expiratory views?

• The radiographic hallmark of an aspirated foreign body is a lung volume that does not change during the respiratory cycle (air trapping)
• On expiration, the affected side remains hyperinflated (ball-valve effect of the AFB)
• Particularly useful for radiolucent objects (e.g. food)
• In younger children, decubitus films may be used instead

Consider a neck x-ray in children with upper airway symptoms such as stridor or voice changes – assess for laryngotracheal AFB

Figure 1 – Paediatric CXR – Hyperinflated left lung with mediastinal shift to the right side. History “eating almonds” followed by 4 days of cough. Image link (Radiopaedia)

Management

Follow local paediatric inhaled foreign body guidelines.

If suspicion is high à urgent referral (ENT/paediatric/paediatric respiratory team depending on local setup)

Definitive management will depend on the FB and the location. Options include:

• Rigid bronchoscopy
• Flexible bronchoscopy
• Bronchoalveolar lavage

Do not delay referral for imaging if the clinical suspicion is strong

A Note on Specific Inhaled Foreign Bodies

• Metallic objects – mechanical obstruction +/- chemical irritation
• Peanuts – inflammatory response due to lipophilic content
• Starchy foods – can expand due to water retention and worsen obstruction

Foreign Body Ingestion

Why it matters

Foreign body ingestion is more common than aspiration, and often benign. The vast majority of ingested objects will pass through the gastrointestinal tract without incident.

However, certain objects can cause rapid and catastrophic complications, including:

• Oesophageal obstruction or perforation
• Fistulae into the trachea or vasculature
• Bowel obstruction or perforation

Management is determined by object type + location + symptoms.

This article does not cover the ingestion of absorbable toxic materials e.g. plants or chemicals. For the management of these ingestions, local policy should be followed, and TOXBASE should be utilised to guide management.

Commonly ingested objects include:

• Coins
• Small toys
• Batteries
• Magnets

History and examination

Ask:

• What was ingested? If more than one, how many?
• When did it happen?
• Has the child had any symptoms?

Most children are asymptomatic, however check for:

• Drooling
• Dysphagia or refusal to eat
• Vomiting (particularly haematemesis)
• Stridor, coughing or gagging (consider aspiration instead)
• Abdominal pain, abdominal distention
• Bowel movements since ingestion
• Sensation of FB

Investigations

First line: X-ray (neck, chest abdomen)

Assess:

• Location (oesophagus vs stomach vs beyond)
• The number of objects
• Progression on serial imaging
• FBs above the level of clavicles suggests upper oesophageal obstruction à ENT referral
• FBs below the level of the clavicles à paediatric surgery/endoscopy (local pathway dependant)

💡 We often use Hand Held Metal Detectors (HHMDs) to localise metallic objects, and to track progression through the gastrointestinal tract without repeated radiation exposure

Management Approach

• Low risk ingestion: asymptomatic, non-hazardous object
  • Discharge with safety netting advice
• Intermediate risk ingestion: unclear history, may have mild symptoms
  • Imaging and senior review
• High risk ingestion: button batteries, magnets, sharp or large objects, and/or a symptomatic child

High Risk Foreign Bodies – Must Not Miss!

⚠️ Button Batteries

• True time-critical emergencies
• The battery generates an electrical current à alkaline burns of the soft tissue
• Tissue damage can occur within 1~2 hours
• Complications include oesophageal perforation, tracheo-oesophageal fistulas and major haemorrhage.

If there is any uncertainty in the history, assume a button battery has been ingested until proven otherwise.

Note that many trusts will have button battery ingestion specific guidelines.

Management:

• Immediate senior clinician involvement
• Immediate X-ray (neck, chest, abdomen)
• The button battery will appear as a circular radio-opaque object, with a double ring or “halo” sign
• If oesophageal à urgent removal
• Top tip:
  • Honey or sucralfate solution can be given to patients >1 year of age, presenting within 12 hours of ingestion
  • Studies show that that early administration can reduce mucosal injury pending removal
  • Do NOT given honey in children <1 year due to the risk of botulism, if there is airway compromise, or if the child is unable to swallow

Figure 1 – Infant CXR – showing oesophageal button battery with “halo sign”. Image link (Radiopaedia)

⚠️ Magnets

• Particularly dangerous when multiple magnets are ingested
• Magnets can attract across the bowel walls à pressure necrosis, perforation and/or fistula formation
• Children may look clinically well despite serious pathology – perforation may already have occurred at presentation, and an asymptomatic well child may be perforated but compensating well.

If there is uncertainty in the regarding whether the child has swallowed one or multiple magnets, always assume that it is multiple.

Note that many trusts will have magnet ingestion specific guidelines.

Management:

• Immediate senior clinician involvement
• Immediate X-ray (neck, chest, abdomen) with frontal and lateral views
• One object on X-ray does not mean that there is only one magnet – magnets may be stacked
• Urgent surgical/paediatric referral depending on local guidelines
• DO NOT discharge suspected multiple magnet ingestion

Figure 3 – Paediatric X-ray (frontal and lateral views) showing metal dense radio-opaque foreign bodies in the Lt upper abdomen Image link (Radiopaedia)

⚠️ Sharp or Large Objects

• Fish bones, needles, glass are all extremely high risk for perforation
• Large objects >6cm long or >2cm wide are a risk for obstruction.
• Immediately involve a senior clinician when managing these patients.

High Yield Clinical Pearls

• Monophonic wheeze suggests obstruction, not asthma
• Normal investigations do not exclude pathology
  • CXR may be normal in aspiration
• Children compensate extremely well
  • A clinically well child may still have serious pathology
• Button battery ingestion is a time critical emergency
• Magnets are deceptively dangerous
  • A single radio-opaque object on X-ray does not exclude multiple magnets
• Always clarify the number of objects ingested – and assume worst case if uncertain

Common Mistakes to Avoid

• Discharging a child with suspected multiple magnet ingestion
  • Even if asymptomatic
• Over-reassurance from a normal examination or imaging
• Delaying referral while awaiting imaging
• Missing unwitnessed aspiration
• Assuming a well-appearing child is low risk
• Failing to consider safeguarding in recurrent or unusual ingestions
• Not considering mental health assessment in developmentally atypical ingestions (e.g. adolescents)

When in doubt, escalate early — these are presentations where delayed recognition carries significant morbidity.

Written by Dr Evy Phillips (Foundation Year 2 Doctor), reviewed by Dr Kiran Raju (Paediatric ST3)

References

Nicola Goodall. (2023). Foreign Body Inhalation in Children. [Online]. RCEM Learning. Last Updated: 8th September. Available at: https://www.rcemlearning.co.uk/foamed/foreign-body-inhalation-in-children/ [Accessed 8 April 2026].

Samual Danaher. (2022). Inhaled foreign bodies. [Online]. Don’t Forget the Bubbles. Last Updated: 13th October 2024. Available at: https://dontforgetthebubbles.com/inhaled-foreign-bodies/ [Accessed 8 April 2026]

D. James, Paed Emergency Medicine Consultant, UHS R. Broomfield, Paed Emergency. (2022). Paediatric Foreign Body Ingestion. [Online]. PIER (Paediatric Innovation, Education & Research Network) Guidelines. Last Updated: March 2022 Available at: https://www.piernetwork.org/foreign-body.html [Accessed 8 April 2026].

Anfang RR et al (2019) pH-neutralizing Esophageal Irrigations as a Novel Mitigation Strategy for Button Battery Injury Laryngoscope, 129:49-57