Clinical diagnosis
Only necessary in patients with significant injury or volume of ingestion
CBC, metabolic panel, lactate, serum calcium (if concern for hydrofluoric<unk>  exposure
ECG
Tylenol/ASA levels if concerned about coingestion (suicidal patients)
Ingestion, consider:
3-View CXR: look for free air under diaphragm or mediastinal free air
CT: if suspect perforation but CXR negative
3-View CXR: look for free air under diaphragm or mediastinal free air
CT: if suspect perforation but CXR negative
Hydrochloric acid
Caustic ingestion
Hydrofluoric acid
Caustic eye exposure 
Agent orange
Caustic dermal burn
Selenium sulfide
Airbag-related burns