Battery ingestion

Ingestion "button" batteries

Airway for obstruction ensuring nothing is stuck in the piriform fossa.
Examine the mouth for signs of chemical burns which may indicate the battery was leaking before ingestion.

Nearest poisons centre who will have a list of battery numbers, sizes and contents Toxbase

Lateral neck and CXR to ensure the battery has gone through the oesophagus into the stomach
(X-ray the abdomen as well as the chest in older children to ensure that an adequate image is obtained)
If it remains in the oesophagus it must be removed immediately
Most batteries pass from the stomach without difficulty, but if a mercury battery remains in the stomach for more than 24 hours and/or is leaking it should be removed (limit for non-mercury batteries is up to 48 hours)
Although there is no strong evidence either way, those in the stomach should be re-xrayed next day [Bestbets]
Endoscopic or magnetic removal should be considered in the first instance
The Poisons Information Service can provide further specific advice.Toxbase

Fever, abdominal pain, vomiting or blood in the stools
Examine the battery once it has been passed to confirm the type and whether it is intact
Consider the need for estimation of blood and urine mercury concentrations