Airway Foreign Bodies

OVERVIEW

Airway foreign bodies (AFBs) are potentially life‑threatening

• AFBs predominantly affect children under 5 years and adults over 65 years – they are rare in other age groups
• A foreign body is any object or substance that is not naturally found in the body and is present where it does not belong.
• Presentations are often subtle – only ⅓ of FB aspirations are recalled by adults – and are misdiagnosed as asthma, COPD, pneumonia, or malignancy. 
• CT is highly sensitive, but radiolucent organic material may be missed — persistent suspicion mandates bronchoscopy.
• In ICU settings, bronchoscopic foreign body removal is usually performed for blood clot removal or aspirated foreign bodies in the setting of trauma 

Flexible bronchoscopy is first‑line in most adults (>90% success), while rigid bronchoscopy remains essential for large, sharp, proximal, or asphyxiating objects.

• See Bronchoscopic removal of foreign bodies for indications, assessment and planning, flexible versus rigid bronchoscopy, retrieval tools and techniques, and critical care scenarios.

CAUSES & RISK FACTORS

In general, consider:

• Impaired swallow (stroke, neuromuscular disease)
• Reduced cough reflex (sedation, intoxication)
• Altered mental status
• Dental procedures, poor dentition
• Elderly patients with occult aspiration

In critical care settings, also consider:

• Head and facial trauma (especially if associated with altered mental status)
• Bleeding (pulmonary haemorrhage or aspiration of blood from other sources, e.g. epistaxis)
• Iatrogenic (e.g. artificial airway fragments from ETT cuff rupture, suction catheter tips, bite block fragments, bronchoscopy tool failure, or tracheostomy care)
• Inhalational injury debris (e.g. burns, soot inhalation)
• Mucus plugs, obstructing casts, bronchiolitis (e.g. prolonged sedation and ventilation, ineffective cough, severe lung inflammation, chronic lung disease)

One may argue whether blood and mucus are really “foreign” as they are not from an exogenous source, however they can be treated as “endogenous” foreign bodies.

PATHOPHYSIOLOGY

Location of FB lodgement

• The right main bronchus is the most common site of lodgment
  • Occurs in 60–70% of cases
  • due to its larger diameter, shorter length, and more vertical angulation compared to the left main bronchus
• FB location varies with patient positioning during aspiration and may occur anywhere within the respiratory tract
• In children, foreign bodies are more likely to lodge in the subglottic region or proximal trachea due to their smaller airway caliber, and life-threatening airway obstruction is more likely

Pathophysiological effects

• Mechanical obstruction – foreign bodies block airflow at the larynx, trachea, or bronchi.
  • Complete obstruction → no airflow → rapid hypoxia → LOC → arrest (classic in laryngeal/tracheal impaction) 
  • Partial obstruction → turbulent flow, wheeze, cough, stridor
  • Distal obstruction → segmental/lobar collapse or hyperinflation depending on valve effect
• Valve (ball‑valve) physiology – airflow pattern varies according to nature of airflow obstruction:
  • Check‑valve (ball‑valve): air enters but cannot exit → air trapping, hyperinflation, mediastinal shift
  • Stop‑valve: no air entry or exit → atelectasis
  • Bypass‑valve: partial obstruction → wheeze, recurrent infection
• Local mucosal injury – foreign bodies cause:
  • Pressure necrosis
  • Ulceration
  • Granulation tissue formation
  • Bleeding (especially with sharp or organic material)
  • Chronic inflammation
• Infection and impaired clearance
  • Obstruction impairs mucociliary clearance → stasis → bacterial overgrowth.
  • Leads to post‑obstructive pneumonia, abscess, fever, productive cough
  • Particularly common with organic material (nuts, seeds) which absorb water and swell, worsening obstruction
• Chemical and inflammatory reactions
  • Some organic foreign bodies release oils and proteins that cause an intense inflammatory response (e.g. Nuts can cause llipid pneumonia, plant matter may lead to granulomatous reactions).
  • Batteries (rarely inhaled) cause caustic injury within a few hours
  • Pill aspirations are also concerning, e.g. iron tablets → rapid disintegration → chemical necrosis → bronchial stenosis; tablet often unrecognisable on bronchoscopy and may require tissue biopsy to to identify iron deposits.
• Impaired gas exchange due to obstruction
  • Ventilation-perfusion (V/Q) mismatch
  • Shunt physiology (atelectasis)
  • Dead space (hyperinflated but poorly perfused segments)
  • Hypoxia and respiratory distress

CLINICAL FEATURES

Children:

• typically present with acute, severe symptoms
• greater risk of immediate life-threatening obstruction

In ambulatory patients:

• Chronic cough (60–85%)
• Dyspnoea
• Unilateral wheeze
• Recurrent same‑lobe pneumonia
• Haemoptysis
• Chest pain
• Up to 10% asymptomatic

In patients who are intubated and ventilated:

• Clinical findings
  • Hypoxia or rising CO₂ not explained by other causes
  • Failure to improve with suctioning (suction is often effective for proximal mucus plugs)
  • Difficulty hand‑bagging: increased resistance, poor chest rise
  • Unilateral breath sounds: decreased or absent on affected side
  • Unilateral hyperinflation or collapse on exam or imaging
  • Wheeze or high‑pitched sounds audible through the ventilator circuit
• Ventilator findings
  • Sudden rise in PIP with normal plateau pressure → increased airway resistance
  • High PIP + high plateau if distal collapse or hyperinflation develops
  • Low delivered tidal volumes despite unchanged settings
  • Obstructive flow waveform: scooped expiratory limb, incomplete return to baseline
  • Auto‑PEEP / air trapping, prolonged expiration
• Haemodynamic instability in severe obstruction due to hypoxia or dynamic hyperinflation (tachycardia, hypotension)
• Post‑obstructive changes
  • fever, consolidation, collapse on CXR
  • Other complications (see below)

COMPLICATIONS

Acute

• Asphyxia and respiratory arrest (especially laryngeal/tracheal FBs)
• Severe respiratory distress, cyanosis
• Stridor, choking, drooling
• Haemoptysis
• Pneumothorax (from distal air trapping)
• Failure to ventilate during resuscitation

Subacute

• Persistent cough, wheeze, dyspnoea
• Recurrent or non‑resolving pneumonia
• Fever
• Unilateral decreased breath sounds
• Hyperinflation or collapse on imaging

Chronic (occurs when diagnosis is delayed, such as when aspiration is unwitnessed)

• Bronchiectasis (due to chronic infection/inflammation)
• Pulmonary abscess
• Granulation tissue and potential for fixed airway stenosis
• Chronic cough and wheeze
• Lobar collapse
• Bronchial strictures
• Misdiagnosis as asthma, COPD, malignancy

INVESTIGATIONS

Bedside

• Ventilator waveform analysis (in intubated patients)
  • increased airway resistance, air trapping, obstructive flow pattern (inferred from standard ICU practice; not directly cited in search results)
• Capnography
  • shark‑fin waveform, delayed upstroke, rising EtCO₂ with obstructive physiology
• Blood gas
  • hypoxia, hypercapnia, respiratory acidosis in significant obstruction 
• Bedside spirometry
  • obstructive pattern, flattened expiratory limb, variable intrathoracic obstruction appearance
  • Decreased peak expiratory flow

Imaging

• Chest X‑ray
  • may show radio‑opaque FB but only directly visualises about 25% of airway FBs
  • Indirect features are more common: segmental/lobar collapse, unilateral hyperinflation, mediastinal shift, post‑obstructive consolidation, or pneumothorax
  • normal CXR does NOT exclude FB (~35% of presentations have normal CXRs)
  • Inspiratory/expiratory films (or lateral decubitus in non‑cooperative patients) may show air trapping on expiratory view, asymmetric lung inflation 
• CT chest
  • High sensitivity (98.8%) and specificity (96.6%) reported
  • Defines site, size, shape, density, complications
  • Radiolucent organic material may still be invisible
  • Virtual bronchoscopy may assist planning of removal
  • Indirect features may be seen: airway obstruction, atelectasis, hyperinflation, post‑obstructive infection
  • often used when diagnosis uncertain 
• Lung ultrasound
  • emerging modality
  • may show absent lung sliding, atelectasis, or consolidation in affected region 

Other

• Flexible bronchoscopy
  • definitive diagnostic test
  • directly visualises FB and associated granulation, mucosal injury, purulence, or airway collapse
  • also therapeutic in many cases (allows removal)
• Rigid bronchoscopy
  • used when flexible bronchoscopy fails or for large/complex FBs
  • confirms diagnosis and allows removal 

MANAGEMENT

From a management perspective, AFB presentations fall into two major categories:

• Asphyxiating — immediately life‑threatening, requires rigid bronchoscopy
• Non‑asphyxiating — stable, allowing planned evaluation, with flexible bronchoscopy 

Resuscitation

• Assess for immediate life threat (asphyxiating AFB)
  • Severe respiratory distress, hypoxemia (e.g. SpO2 <90%)
  • Inspiratory or biphasic stridor, inability to vocalise
  • Loss of consciousness, cardiac arrest
• Conscious patient with suspected AFB
  • Effective cough present
    • Encourage coughing
    • Keep patient calm, avoid agitation
    • Position upright/ semi-upright in position of comfort
    • Do not perform back blows or abdominal thrusts
    • Continuous monitoring; prepare for deterioration
    • Avoid positive pressure ventilation if possible, due to risk of FB impaction
  • Ineffective cough / severe obstruction
    • Adults & children >1 year
      • 5 back blows
      • If ineffective perform 5 abdominal thrusts
      • Alternate until relief or patient becomes unconscious
    • Infants (<1 year)
      • 5 back blows
      • If ineffective perform 5 chest thrusts (no abdominal thrusts).
      • Alternate until relief or unconscious.
• Unconscious patient with suspected AFB
  • Assess responsiveness; call for help; activate resuscitation team (including senior airway support)
  • Begin CPR immediately (ALS/APLS), beginning with compressions
  • Airway
    • Open airway, look for visible FB prior to ventilations
      • Remove FB only if easily graspable (e.g. with Magill’s forceps)
      • Do not perform blind finger sweeps
    • Attempt bag‑mask ventilation with high flow O2
    • Perform laryngoscopy to remove visible FB using Magills forceps ASAP
      • This must be performed as soon as personnel and equipment are available – do not delay
      • Do not interrupt compressions
    • If unable to remove FB during laryngoscopy
      • If FB is at or above the vocal cords,perform emergency front‑of‑neck access (FONA)
      • If FB is below the vocal cords
        • Perform intentional right main bronchus intubation to advance FB into right main bronchus intentionally
        • Retract ETT back into trachea above carina
        • Position patient right side down to ventilate the left lung
        • If unable to intubate, perform positive pressure ventilation to force FB into either the left or right main bronchus to allow ventilation of one lung
  • Breathing
    • Once airway secured, ventilate with FiO2 1.0 to target SpO2 94-98%
    • Prepare for bronchoscopy (rigid preferred for asphyxiating FB).
  • Circulation
    • Continue standard ALS algorithm if cardiac arrest.
  • Post-resuscitation
    • Supportive care and monitoring (see below)
    • Identify complications (see below)
    • Expedite transfer to OT for bronchoscopy and ensure complete FB removal
• If complete obstruction with arrest, FB removal takes precedence over all other resuscitation measures

Management of asphyxiating AFB

• Rigid bronchoscopy (gold standard)
  • Advantages: airway control, ventilation capability, large working channel.
  • Technique:
    • Supine with neck extension; shoulder roll/occiput bolster.
    • TIVA (e.g. ketamine/propofol/dexmedetomidine); short‑acting paralytics for intubation.
    • Jet ventilation in children; closed‑circuit ventilation in adults.
    • Systematic airway inspection; flexible scope may be passed through rigid barrel.
  • Extraction principles
    • Three steps: dislodge → secure → remove.
    • Retrieval tools:
      • Graspable: serrated rigid forceps / rat‑tooth forceps.
      • Smooth/rounded: Dormia basket or fish‑net forceps.
      • Organic: cryoprobe (“adheres the object to the frozen probe tip”).
      • Impacted: Fogarty balloon.
      • Sharp: fine grasping forceps with withdrawal into rigid barrel.
      • Granulation‑covered: electrocautery debridement.
      • Large objects → en bloc removal of bronchoscope + forceps + foreign body.
    • Mandatory post‑extraction re‑inspection for residual fragments.
• Flexible bronchoscopy in asphyxiation
  • Can be used via SGA or ETT when rigid unavailable.
  • Limitations: small working channel, poorer airway and ventilation control, 15–25% conversion rate to rigid.
  • Should only be attempted with immediate rigid backup.

Management of Non‑Asphyxiating AFBs (adequate ventilation, no hypoxemia, no immediate compromise)

• Diagnostic approach
  • Imaging first in adults: multidetector CT preferred.
  • Planned Flexible bronchoscopy technique (~90% success rate) under appropriate anaesthesia
• Equipment
  • Flexible bronchscope sizes:
    • Infants: 3.2 mm OD / 1.7 mm channel
    • Older children: 4.0–4.9 mm OD / 2.0 mm channel
    • Adults: 5.8–6.2 mm OD / 2.8–3.2 mm channel
  • Full retrieval toolkit available (forceps, baskets, cryoprobe, Fogarty).
• Sedation
  • Adults/older children → conscious sedation + local anaesthesia
  • Infants/small children → GA with SGA
  • Adults with cardiopulmonary disease require optimisation.
• Extraction principles
  • En bloc withdrawal of bronchoscope, instrument, and foreign body.
  • Oral route preferred (avoid nasal impaction).
• Failed flexible bronchoscopy should be followed by immediate rigid bronchoscopy, not repeated attempts.

Supportive care and monitoring

• SpO₂, ECG, BP, capnography monitoring during bronchoscopy

Seek and treat complications

• Hypoxemia
• Pneumothorax
• Airway edema
• Post-obstructive pulmonary oedema
• Post‑obstructive pneumonia

Referrals

• ENT for rigid bronchoscopy (may be performed by other specialities such as cardiothoracic surgeons)
• Respiratory physician for flexible bronchoscopy (may be performed by intensivist in ICU patients)

REFERENCES AND LINKS

LITFL

• Inhalational emergency (case-based Q&A)
• CCC – Bronchoscopic removal of foreign bodies

Journal articles

• Chi J, Bai Y. Bronchoscopic management of airway foreign bodies in adults: a narrative educational review. Front Med (Lausanne). 2026 Mar 4;13:1779715. doi: 10.3389/fmed.2026.1779715. PMID: 41859138; PMCID: PMC12996173.
• Goyal R, Sehgal IS, Agarwal R. Foreign body removal. Curr Opin Pulm Med. 2026 Jan 1;32(1):63-73. doi: 10.1097/MCP.0000000000001225. Epub 2025 Oct 10. PMID: 41076577.
• Hewlett JC, Rickman OB, Lentz RJ, Prakash UB, Maldonado F. Foreign body aspiration in adult airways: therapeutic approach. J Thorac Dis. 2017 Sep;9(9):3398-3409. doi: 10.21037/jtd.2017.06.137. PMID: 29221325; PMCID: PMC5708401.
• Küpeli E, Khemasuwan D, Lee P, Mehta AC. “Pills” and the air passages. Chest. 2013 Aug;144(2):651-660. doi: 10.1378/chest.13-0080. PMID: 23918109.
• Kupeli E, Khemasuwan D, Tunsupon P, Mehta AC. “Pills” and the air passages: a continuum. Chest. 2015 Jan;147(1):242-250. doi: 10.1378/chest.14-0531. PMID: 25560862.

FOAM and web resources

• RCH Melbourne – Clinical Practice Guidelines : Foreign bodies inhaled