Corrosive Poisoning: Acids, Alkalis and Why You Must Not Lavage

Corrosive ingestion is a surgical emergency dressed up as a poisoning. The examinable core is a single contrast — acids and alkalis injure tissue by different mechanisms, and that difference determines where the damage lands and what happens afterwards.

At a glance

Acids form a firm eschar that acts as a barrier and partly limits how deep the burn goes, and they tend to pass through the oesophagus quickly to pool in the stomach. Alkalis dissolve tissue progressively and keep penetrating, which is why oesophageal perforation and later stricture are so characteristic.

Clinical features

• Immediate severe pain in the mouth, throat, retrosternally and in the epigastrium.
• Drooling, odynophagia, refusal to swallow — a useful early marker of significant oesophageal injury.
• Burns and staining of lips, tongue and palate. Sulphuric acid stains blackish-brown, nitric acid yellow, hydrochloric acid greyish.
• Hoarseness and stridor indicate laryngeal oedema and a threatened airway.
• Haematemesis, shock, and signs of perforation — a rigid abdomen or surgical emphysema in the neck.

Absence of visible oral burns does not exclude serious oesophageal or gastric injury. This is the single most important safety point in the topic, and it is why endoscopy rather than inspection decides management.

What not to do

• No gastric lavage — the tube may perforate already necrotic tissue, and re-exposing the oesophagus to the corrosive on the way back up doubles the injury.
• No emetics — for the same reason.
• No neutralisation — acid-base reactions are exothermic and add a thermal burn to a chemical one.
• No activated charcoal — it does not bind corrosives and obscures the endoscopic view.
• No blind nasogastric tube insertion.

Management

1. Airway first. Assess for stridor and oedema; secure the airway early if there is any doubt, because swelling progresses.
2. Nil by mouth, intravenous fluids, analgesia, proton pump inhibitor.
3. Erect chest and abdominal radiographs to look for free air or mediastinal emphysema; CT if perforation is suspected.
4. Upper gastrointestinal endoscopy within 12 to 24 hours (and generally not after 48 hours, when tissue is weakest) to grade injury. The Zargar classification runs from grade 0 (normal) through mucosal oedema and erythema, superficial and deep ulceration, to grade 3 with necrosis and grade 4 perforation. Grade determines feeding, stricture risk and follow-up.
5. Surgery for perforation, full-thickness necrosis or uncontrolled bleeding.
6. Long-term follow-up: strictures typically appear from two to eight weeks and are managed with dilatation; oesophageal carcinoma risk is raised for decades after significant alkali injury, so surveillance is warranted.

Forensic points

Vitriolage is the throwing of corrosive acid on a person, usually the face, to disfigure rather than to kill. It carries specific statutory offences and mandatory reporting duties in India. Document injuries meticulously with photographs and measurements, preserve stained clothing, and record the exact pattern of splash and run-off marks — these establish the direction from which the substance was thrown.

Last-minute checklist

• Acid, coagulative, stomach. Alkali, liquefactive, oesophagus.
• No lavage, no emetics, no neutralisation, no charcoal.
• Absent oral burns prove nothing.
• Endoscopy at 12–24 hours; Zargar grading.
• Stricture at weeks; carcinoma at decades.

Frequently asked questions

Why is gastric lavage contraindicated in corrosive poisoning?

The tube can perforate tissue that is already necrotic, and bringing the corrosive back up exposes the oesophagus to a second injury. The risk far outweighs any benefit.

Why do alkalis damage the oesophagus more than acids?

Alkalis cause liquefactive necrosis, dissolving protein and fat so the injury keeps penetrating. They also cause less immediate pain, so more is swallowed and it lingers longer in the oesophagus.

Why should a corrosive burn not be neutralised?

Neutralisation reactions release heat. Adding a thermal burn to chemically damaged tissue makes the injury worse rather than better.

References

• Bailey & Love’s Short Practice of Surgery — corrosive injury of the oesophagus.
• Reddy KSN. The Essentials of Forensic Medicine and Toxicology.
• Zargar SA et al., endoscopic classification of corrosive injury.