Nasal foreign body and button-battery injury — branching viva

Opening — the two-year-old with a missing battery

Examiner: A two-year-old is brought in after a button battery went missing from a remote control. He is well and afebrile, but a shiny metallic disc is wedged against the right side of the nasal septum. He ate 30 minutes ago. Talk me through your immediate thoughts and actions. [3]

Candidate should cover: recognition that a button battery in the nose is a time-critical emergency to be removed immediately, without waiting for a fasting period, because alkaline liquefactive necrosis begins within one to two hours of mucosal contact; the setting decision — theatre and ENT for the uncooperative or embedded case; and the application of topical decongestant and anaesthesia with direct-vision removal. The child's wellbeing does not change the urgency; the object type does. [5]

Branch 1 — the mechanism

Examiner: Explain to me why a small disc like this can perforate a septum within hours. [5]

Candidate should cover: the battery drives an electrolysis current against moist mucosa; hydroxide ions accumulate at the negative pole, the tissue turns alkaline, and alkaline (liquefactive) necrosis dissolves tissue; compounded by thermal injury from the local current and pressure necrosis from tight contact blocking the mucosal blood supply; damage begins within one to two hours and clinically significant septal injury can develop within hours. [6]

Branch 2 — the battery versus the coin

Examiner: If the disc had not been seen clearly, how would you tell a button battery from a coin on imaging? [9]

Candidate should cover: a plain lateral X-ray of the nasal cavity; a battery is thicker than a coin with a step-off or bevelled edge and often a double-ring (halo) sign where the cell faces meet the rim, whereas a coin is thin, flat and uniform; and the principle to treat an unidentifiable round metallic object in a young child as a battery until proven otherwise, and to look actively for a second battery. [9]

Branch 3 — the four-year-old with a bead

Examiner: Now a different child: a four-year-old with a week of foul-smelling, blood-stained left-sided discharge and a smooth round bead on examination. How do you remove it? [11]

Candidate should cover: the diagnostic maxim that a unilateral foul-smelling discharge in a two-to-five-year-old is a nasal foreign body until proven otherwise; first-line positive pressure (the parent's kiss) for an anterior inert object after topical decongestant; the instrument matched to the object — a right-angle hook passed behind a smooth round bead rather than forceps, which cannot grip a sphere and push it deeper; and the absolute contraindication of a blind finger sweep, which pushes the object toward the airway. [10] [1]

Branch 4 — after the battery is out

Examiner: Returning to the battery child — it has just been removed. What now? [3]

Candidate should cover: re-inspect for a second battery and for septal injury, irrigate the cavity, and consider a topical neutralising agent (medical honey or a carbomer gel) as an adjunct that may reduce tissue injury but does not substitute for the urgent removal already done; and refer to ENT for burn surveillance, because septal perforation, synechiae and stenosis can continue to evolve for days after the battery is out. [6] [7]