A 5-year-old girl is brought to the ENT clinic 3 weeks after accidental ingestion of a button battery while playing. Her parents report she initially had mild cough and throat discomfort, which resolved within 2 days. She is currently asymptomatic with normal oxygen saturation and no stridor. On flexible laryngoscopy, the larynx appears normal. A neck X-ray (anteroposterior and lateral views) shows a radiopaque disc-shaped object at the level of the proximal trachea, just below the vocal cords. What is the most appropriate next step in management?

Explanation

## Clinical Context and Diagnosis **Key Point:** A button battery lodged in the **proximal trachea** (below the vocal cords) is a **surgical emergency** requiring urgent rigid bronchoscopy for removal, regardless of symptom duration or current clinical stability. ### Why Button Battery Is Different From Other Foreign Bodies **High-Yield:** Button batteries pose a unique hazard because of **electrochemical injury**, not mechanical obstruction: 1. **Alkaline electrolyte leakage** — creates caustic hydroxide ions 2. **Thermal injury** — exothermic reaction generates heat (up to 70°C) 3. **Tissue necrosis** — occurs within **2–4 hours** of contact 4. **Perforation risk** — can erode through tracheal wall, larynx, or esophagus **Warning:** The **absence of symptoms does not indicate safety**. Electrochemical injury progresses silently. Perforation, mediastinitis, and tracheal stenosis can develop even after symptom resolution. ### Timeline of Injury in This Case ```mermaid flowchart TD A[Button battery ingestion]:::outcome --> B[Initial symptoms: cough, throat discomfort]:::outcome B --> C[Symptoms resolve by day 2]:::outcome C --> D[Silent electrochemical injury continues]:::urgent D --> E[Mucosal ulceration, necrosis]:::urgent E --> F[Risk: perforation, mediastinitis, stenosis]:::urgent G[Day 0-4: Urgent removal needed]:::action G -.->|If delayed| H[Irreversible tissue damage]:::urgent ``` **Clinical Pearl:** The **3-week delay** in this case is concerning. While the battery has not yet caused complete perforation (patient is asymptomatic), electrochemical injury is ongoing. Urgent removal is still indicated to prevent late complications like tracheal stenosis or mediastinitis. ### Management Algorithm for Airway Foreign Bodies | Foreign Body Type | Location | Management | |-------------------|----------|-------------| | Button battery | Larynx/trachea | **Urgent rigid bronchoscopy** (< 4 hours) | | Button battery | Esophagus | Urgent removal (< 12 hours) | | Food/organic | Trachea, asymptomatic | Rigid bronchoscopy (elective) | | Food/organic | Trachea, symptomatic | Urgent rigid bronchoscopy | | Inert object | Trachea, stable | Rigid bronchoscopy (urgent) | **Key Point:** Button batteries in the **airway** (larynx, trachea) require removal within **4 hours** of ingestion. Even if symptoms resolve, electrochemical injury continues and perforation risk remains high. ### Why Other Options Are Inappropriate **Observation with serial imaging:** Button batteries cause **progressive tissue necrosis** that is not halted by waiting. Serial X-rays delay definitive treatment and allow irreversible damage. **PPI therapy:** Acid suppression is used for esophageal button battery ingestion to slow corrosive injury, but it does NOT prevent airway perforation. A battery in the trachea requires mechanical removal. **Local anaesthesia removal:** Topical anaesthesia is inadequate for tracheal foreign body removal because: - No airway control during instrumentation - Risk of FB dislodgement into lower trachea - Inability to ventilate if complete obstruction occurs - Rigid scope under general anaesthesia is the standard **High-Yield Mnemonic — Button Battery Airway (BBA):** - **B** — Burn (electrochemical injury, not mechanical) - **B** — Below vocal cords (proximal trachea is highest risk) - **A** — Airway emergency (remove urgently, not expectantly) [cite:Cummings Otolaryngology 6e Ch 197; American Academy of Pediatrics 2023 Button Battery Ingestion Guidelines]