Inhaled foreign body

Definition | Aetiology | Pathophysiology | Risk Factors | Signs and Symptoms | Investigations | Management

Definition

Inhaled foreign body refers to the aspiration of a foreign object into the respiratory tract, leading to partial or complete airway obstruction, with potential for severe respiratory distress or secondary complications such as pneumonia.

Aetiology

  • Accidental aspiration of food particles (e.g., nuts, seeds, grapes).
  • Non food items (e.g., small toys, beads, coins).
  • Neuromuscular disorders increasing aspiration risk.
  • Poor chewing ability in young children.

Pathophysiology

  • Obstruction may occur in the larynx, trachea, or bronchi (most commonly the right main bronchus).
  • Partial obstruction may allow air movement but cause stridor, wheezing, or coughing.
  • Complete obstruction leads to asphyxia and requires urgent intervention.
  • Delayed presentation may result in infection, lung collapse, or chronic cough.

Risk Factors

  • Age under 3 years (incomplete chewing and immature protective reflexes).
  • Eating while laughing, crying, or running.
  • Neurological or developmental conditions affecting swallowing.
  • Lack of parental supervision during feeding or play.

Signs and Symptoms

  • Acute symptoms:
    • Sudden onset coughing, choking, or gagging.
    • Stridor or wheezing (indicative of upper airway involvement).
    • Cyanosis and respiratory distress in severe cases.
    • Apnoea or loss of consciousness in complete obstruction.
  • Delayed symptoms (missed diagnosis):
    • Persistent cough.
    • Recurrent pneumonia or localised wheeze.
    • Unilateral decreased breath sounds.

Investigations

  • Clinical assessment: history of choking event, examination for stridor or asymmetric breath sounds.
  • Chest X-ray: may show air trapping, atelectasis, or a visible foreign body if radiopaque.
  • Fluoroscopy: assesses dynamic airway collapse in subtle cases.
  • CT scan: indicated if chest X-ray is inconclusive but suspicion remains high.
  • Rigid bronchoscopy: definitive investigation and treatment.

Management

1. Immediate Management:

  • Partial obstruction: encourage coughing if the child is stable.
  • Complete obstruction: perform back blows and chest thrusts (infants) or Heimlich manoeuvre (older children).
  • Emergency airway management: intubation or tracheostomy if conventional methods fail.

2. Definitive Management:

  • Rigid bronchoscopy: gold standard for foreign body removal.
  • Flexible bronchoscopy: used in selected cases for diagnostic purposes.

3. Post-removal Care:

  • Monitor for airway oedema, aspiration pneumonia, or persistent symptoms.
  • Consider prophylactic antibiotics if secondary infection is suspected.

4. Referral:

  • Paediatrics: all cases of suspected inhaled foreign body should be urgently referred.
  • Respiratory specialist: if there is persistent respiratory compromise or secondary complications.
  • ENT: if upper airway obstruction requires specialised intervention.