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Caustic ingestion, button batteries and foreign bodies
In caustic ingestion, protect the airway first, do not neutralise, do not induce vomiting and do not give charcoal, and grade the injury by endoscopy within 12–24 hours; a button battery lodged in the oesophagus is an emergency that needs endoscopic removal within two hours.
Why it matters in the exam
Questions on this topic are built on a child who swallowed a cleaning product or a battery, or an adult who swallowed a caustic in a suicide attempt. The correct answer starts with assessing the airway — drooling, stridor and voice change signal pharyngeal and laryngeal injury — and continues with early endoscopy. Common distractors are milk or vinegar "to neutralise", induced vomiting, activated charcoal and a blind gastric tube.
The difference between agents is also tested: alkalis (drain cleaners, concentrated bleach) cause liquefactive necrosis that penetrates deeply, mainly in the oesophagus; acids cause coagulative necrosis and mainly injure the stomach. The absence of mouth burns does not exclude oesophageal injury. The late complication is oesophageal stricture after weeks, and the risk of oesophageal cancer rises after years.
Button batteries are a separate and important topic: the battery generates an electric current within the oesophageal mucosa and causes a deep burn within hours, so an X-ray showing a "double ring" in the oesophagus demands urgent removal. In a child aged one year or more who swallowed a battery within the last 12 hours, honey can be given on the way to hospital to limit the damage. Once a battery has moved on into the stomach in a patient without symptoms is usually observed, but swallowing several magnets needs a surgical opinion because of the risk of perforation.
Key points
- Airway first — drooling, stridor and voice change are warning signs.
- No neutralising, no vomiting, no charcoal, no blind gastric tube.
- Endoscopy within 12–24 hours to grade the injury.
- Button battery in the oesophagus — removal within two hours; honey on the way for a child aged one year or more.
- Late complications: oesophageal stricture and an increased cancer risk.
Summary table
| Situation | Typical finding | Danger | Action |
|---|---|---|---|
| Alkali ingestion | Drooling, painful swallowing, sometimes no mouth burns | Deep oesophageal necrosis, perforation, stricture | Airway, nil by mouth, endoscopy within 12–24 hours |
| Acid ingestion | Abdominal pain, bloody vomiting | Gastric injury, acidosis | As above; CT if perforation is suspected |
| Button battery in the oesophagus | Double ring on X-ray, drooling, food refusal | Burn within two hours, aorto-oesophageal fistula | Endoscopic removal within two hours |
| Battery in the stomach or bowel | No symptoms | Usually low | Observation and repeat X-ray according to age and size |
| Several magnets | Sometimes no symptoms | Bowel perforation between loops | Surgical opinion, early removal |
| Impacted food bolus | Drooling, cannot swallow saliva | Aspiration, perforation | Urgent endoscopy; look for eosinophilic oesophagitis |
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Sources
- ESGE Guideline: Removal of foreign bodies in the upper gastrointestinal tract in adults, 2016 — Indications and timing
- NASPGHAN Clinical Report: Management of ingested foreign bodies in children, 2015 — Button batteries and magnets
- Goldfrank's Toxicologic Emergencies, 11th edition (2019) — Caustics
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.