Foreign-body aspiration — structured clinical encounter

Station brief (candidate)

You are the paediatric registrar in the emergency department. A 2-year-old boy is brought in an hour after a witnessed choking episode while eating peanuts: he coughed forcefully, went briefly blue, then settled and now looks well. On examination he is alert, pink and playing, afebrile, with an intermittent cough, a subtle monophonic wheeze over the right chest and slightly reduced air entry on the right. Oxygen saturations are 98 percent in air, and his chest radiograph is reported as normal. The team asks you to establish the diagnosis and the reasoning, decide on investigation and management, and set a prevention plan. You have 12 minutes with the team and 5 minutes for examiner discussion. [1]

Information available on request

• Previously well, fully immunised 2-year-old; witnessed choking on peanuts an hour ago. [1]
• Coughed forcefully and went briefly blue, then settled within a minute. [1]
• Examination: alert, pink, playing; intermittent cough; subtle right-sided monophonic wheeze; slightly reduced air entry on the right; afebrile; saturations 98 percent. [3]
• Chest radiograph reported as normal; no radio-opaque object seen. [7]
• Cough is currently effective; the child is not in distress. [6]

Tasks

1. Give the diagnosis and explain why the history outweighs the normal examination and radiograph. [3]
2. Explain why the chest radiograph can be normal and what indirect signs and additional views you would consider. [7]
3. State your definitive management and justify proceeding despite the normal radiograph. [8]
4. State what you would do if he suddenly deteriorated with an ineffective cough. [6]
5. Give a prevention plan for the family. [6]

Marking anchors

Must-hit

• Diagnoses a probable inhaled foreign body (aspirated peanut) on the strength of the witnessed choking history, which is the strongest single predictor and outweighs a well examination and a normal radiograph, both of which have imperfect sensitivity. [3] [1]
• Explains that most objects are radiolucent so the film is often normal, and looks for indirect signs — unilateral air trapping and hyperinflation with mediastinal shift, or lobar collapse — using expiratory or lateral decubitus views to unmask air trapping. [7]
• Proceeds to rigid bronchoscopy under general anaesthesia as the definitive diagnostic and therapeutic step, justified because a convincing choking history is itself an indication regardless of the radiograph. [8] [1]

Merit

• Names the anatomical reason for a right-sided object (wider, shorter, more vertical right main bronchus) and cites the meta-analytic evidence that history, examination and imaging each have imperfect sensitivity, so none excludes aspiration. [7] [1]

Fail

• Discharges the child because he looks well and the radiograph is normal, missing the retained object. [1]
• In a sudden deterioration with an ineffective cough, fails to apply the choking algorithm (five back blows then five abdominal thrusts in this child over one year, progressing to CPR if unconscious, no blind finger sweeps). [6]