<aside> 📘 Role of endoscopy in caustic injury of the esophagus. World J Gastrointest Endosc. 2018

Ingestion of Caustic Substances. NEJM, 2020

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Flowchart

Pathophysiology

Type of Substance	pH Range	Mechanism	Primary affected site
Alkali	pH > 12	liquefactive necrosis	Esophagus (rapid liquefaction and damage continues until the alkali is neutralized or diluted)
Acid	pH < 2	coagulative necrosis	Stomach (Acidic substances have less surface tension; therefore, they pass rapidly through the esophagus)

Caustic injury to the duodenum is less frequent and less severe due to pyloric spasm.
Caustic injury to the esophagus starts within minutes after ingestion
Any attempt to induce vomiting or lavage can exacerbate the damage

Phase	Timeframe	Description
Phase of acute necrosis and thrombosis	1-4 days after caustic ingestion	Acute necrosis and thrombosis occur during this phase.
Phase of ulceration and granulation	3-12 days after caustic ingestion	Mucosal sloughing, bacterial invasion, and granulation formation are evident. The esophagus is in its most friable phase. Any manipulation, such as endoscopic examination or dilatation, should be done with great care.
Healing phase	Starts 3 weeks after injury, lasting 1-6 months	This phase marks the beginning of wound healing. Surgery for stricture cases unamenable to dilatation should be postponed until after this period.

The primary goal during acute injury is the stabilization of the patient.

What to Do	Airway management. Signs for airway injury e.g., hoarseness, stridor and poor ventilation
	Use Direct laryngoscopy to evaluate laryngeal edema.
	Take details about the substance ingested, amount, time of ingestion, pre-hospital treatment, and cause of ingestion.
	Volume resuscitation. Keep the patient NPO. Administer broad-spectrum intravenous antibiotics.
What Not to Do	Avoid Emetics and Neutralizing Agents
	Do not insert Nasogastric Tube

Treatments	Recommendations
Glucocorticoid	1. Prolong glucocorticoid therapy had no longer suggested in children or adult

However, 3 days of methylprednisolone(1g per 1.73m2 of BSA per day) showed shorter duration of parental nutrition in children with more than grade 2B injuries | | Sucralfate | Atypically rapid healing and significantly fewer symptomatic strictures | | Mitomycin C | Apply endoscopically show fewer subsequent dilatation and long strictures However, whether mitomycin C increases the long-term risk of malignant transformation still unclear |

Timing	Criteria	Description
< 24-48 hours	Early Endoscopy Timing	Performed ASAP. Recommended for initial diagnosis and to identify patients(about 30% with no injury) who can be discharged promptly
48-96 hours	Delayed Endoscopy	Esophagus becomes
fragile and easily perforated due to ulceration or granulation phase may be started.
> 96 hours	Safety Window for Endoscopy	Some reports confirm safety, but caution is advised after a certain point.