ENT: Foreign Body (FB) in Air Passages
High-Yield Diagnostic & Clinical Management for Board Review
A Foreign Body (FB) in the airway is a common pediatric emergency. It is critical to distinguish between laryngotracheal FBs (life-threatening) and bronchial FBs (may be occult).
1. Clinical Presentation: “The Classic Triad.”
- The classic triad for bronchial foreign body is: Wheeze, Cough, and Decreased breath sounds.
- History: Often an acute episode of choking/gagging followed by a symptom-free interval.
2. Localization & Imaging Findings
| Site | Key Radiographic Findings |
|---|---|
| Larynx/Trachea | May present with stridor and neck soft tissue swelling. |
| Bronchus | Obstructive emphysema (hyperinflation) or atelectasis. |
3. High-Yield Clinical Pearls
- Right Main Bronchus: The most common site for FB impaction due to the bronchus being wider, shorter, and more vertical.
- “Ball-Valve” Effect: Partial obstruction allowing air in but preventing expiration leads to mediastinal shift away from the affected side during expiration.
- Diagnostic Gold Standard: Rigid Bronchoscopy is both diagnostic and therapeutic.
- Crucial Caveat: A normal chest X-ray does NOT rule out a foreign body. If clinical suspicion is high, proceed to bronchoscopy.
- Peanut FB: Highly irritating to the bronchial mucosa, leading to vegetal bronchitis (severe inflammatory response).