The button battery in the nose — a paediatric time-critical emergency

(a) Diagnosis, mechanism, and urgency (3 marks).

• The diagnosis is a button battery retained in the right nasal cavity for approximately three days — the foul smell, the blood-stained discharge, and the visible metallic disk against the septum, confirmed by the halo sign on the X-ray, are diagnostic.
• The mechanism of injury is electrolysis — the battery, lodged against the mucosal surface of the septum, drives an electrolytic current through the tissue fluid. At the negative pole, electrolysis generates hydroxide, producing a locally alkaline environment that liquefies the tissue. This is an alkaline liquefactive necrosis — every lodged ear or nose battery in the reported series produced tissue destruction, including septal perforation and canal necrosis with exposed bone.^[4]
• The urgency is time-critical — the necrosis progresses within hours and continues after removal. A button battery in the nose is removed promptly, never observed. Three days of retention far exceeds the reported median impaction of 4 hours; in a 10-year series of 45 children, late septal perforation reached 18% against 4.4% early, so delayed structural injury must be assumed.^[1][4]

(b) Immediate ED management, the removal technique, and the post-removal care (6 marks).

• Position and immobilise the child — upright on a parent's lap with the bear-hug hold, or in a papoose; consider procedural sedation (ketamine 1 to 1.5 mg/kg intravenously or 4 mg/kg intramuscularly) for the uncooperative child to allow a single best attempt.^[6][7][8]
• Anaesthetise and vasoconstrict — place a cotton pledget soaked in topical lidocaine with a vasoconstrictor in the right nostril to anaesthetise the mucosa and shrink the turbinate.
• Remove under direct vision with the headlamp and the nasal speculum — grasp the battery with the alligator forceps at the rim (taking care not to push it deeper), or pass a right-angle hook behind the battery and lever it forward. Never irrigate blindly — fluid provides an electrolyte bath that enhances the electrolytic current and hydroxide formation.
• Irrigate the cavity with saline after removal to clear the alkaline residue and reduce the ongoing injury.
• Inspect both nostrils for a second FB, and assess the septum for the extent of the mucosal injury and any exposed cartilage.
• Post-removal care — analgesia and refer immediately to ENT for endoscopic assessment; saline irrigation is the commonest reported post-removal care with topical mupirocin also commonly used; do not discharge without an ENT review of the septal injury, since two in five children historically left with no follow-up plan.^[1][4]

(c) Complications and disposition (4 marks).

• The acute complications are the mucosal eschar and necrosis, the septal perforation (the alkaline necrosis erodes through the cartilage), and the epistaxis from the mucosal slough — eschar in 44.4%, necrosis in 31% and early perforation in 4.4% in the reported series.
• The delayed complications include the late septal perforation (18% — a fourfold rise from early evaluation) and persistent symptoms among those followed: nasal discharge (44.4%), obstruction (17%) and epistaxis (12%).
• The disposition is admission or observation for the septal assessment, definite ENT follow-up for the delayed perforation review, and parental counselling on the long-term outlook — post-removal care varies considerably and low follow-up rates are a critical gap in management.
• The safety-net — return for any epistaxis, fever, obstruction, or visible deformity.^[1]

(d) The X-ray distinction and the duration of retention (2 marks).

• A button battery on X-ray shows the double-rim (halo) sign on the anteroposterior view — reliable in batteries 20 mm and above — and a step-off on the lateral view, visible in batteries of all diameters. A coin shows a homogeneous density at all angles. The two-view X-ray (anteroposterior and lateral) distinguishes them, though a pot magnet can simulate the double-rim sign.^[5]
• The duration of retention is the key prognostic variable — the reported median impaction is only 4 hours, yet late perforation still reached 18%; three days of retention (as here) mandates assuming delayed structural injury. The mechanism continues after removal because the alkali is already in the tissue; hence the saline irrigation and the ENT review.^[1][5]