A 2.

Button batteries lodged in the esophagus require urgent endoscopic removal due to risk of tissue necrosis, perforation, and tracheoesophageal fistula within hours. Batteries beyond the esophagus may pass spontaneously if the child is asymptomatic.

Toronto Notes 2023 – Pediatrics, “Foreign Body Ingestion”:

“Button batteries in the esophagus are medical emergencies and must be removed immediately. Batteries in the stomach or intestines may be observed if the child is asymptomatic.”

MCCQE1 Objectives (Pediatrics > 78-2: Gastrointestinal Emergencies):

“Candidates must identify when foreign body ingestion poses immediate risk and requires emergency intervention.”

Batteries in the stomach or intestines (A–C, E) usually pass without complication, especially if the child is asymptomatic and the battery is < 2 cm.

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