Paediatricsniche
A 20-month-old girl is brought to a metropolitan emergency department 45 minutes after her brother saw her swallow a 20 mm lithium button battery from a remote control. She is settled, swallowing her own saliva, and has taken a small drink without difficulty; her airway is clear and her observations are normal. A chest radiograph shows the battery, with a halo around its rim, lodged in the upper oesophagus. The surgical and endoscopy teams have been called and theatre is being organised. Which one of the following should be done while she waits for theatre?