Caustic Oesophageal Injury: Characteristics and Management
Acids primarily cause severe gastric rather than oesophageal injury in caustic ingestion cases, as they tend to affect the stomach more significantly than the esophagus. 1
Mechanism of Injury by Caustic Agents
Acids vs. Alkalis
Acids:
- Cause coagulative necrosis that limits penetration
- Primarily affect the stomach rather than esophagus 1, 2
- Rapidly transit through the esophagus and pool in the stomach, causing more severe gastric damage 2
- Still can cause esophageal injury in 87.8% of cases, but the pattern of injury differs from alkalis 2
Alkalis:
- Cause liquefactive necrosis (not coagulative) 1
- Penetrate deeper into tissues
- More commonly cause severe esophageal damage
- Can lead to higher rates of esophageal stricture formation
Diagnostic Approach
Endoscopy in Caustic Injuries
- Upper endoscopy is NOT contraindicated in the acute phase 1
- Endoscopy should be performed within the first 12-48 hours after caustic ingestion 1
- Endoscopy remains the mainstay diagnostic tool to define extent and severity of injury 3
- Absence of oral lesions or symptoms does not reliably predict esophageal injury severity 1, 3, 4
Imaging Studies
- CT is increasingly preferred over endoscopy for initial evaluation 1, 5
- Contrast-enhanced CT outperforms endoscopy in detecting transmural injuries
- Better predicts esophageal stricture formation
- Avoids risk of perforation during endoscopy
- Can evaluate surrounding tissue damage
Management Considerations
Inappropriate Interventions
- Early induced emesis is NOT helpful and is contraindicated 6
- May cause additional trauma or perforation
- Increases mucosal contact time with the caustic agent
- Recommended by the American Heart Association not to induce vomiting 6
Proper Management
- Initial laboratory evaluation should include CBC, electrolytes, liver tests, pH, lactate 1
- Radiographic evaluation to assess for perforation 1
- Early endoscopic evaluation (within 12-48 hours) 1
- Timely management of strictures with dilatation 1
Prognostic Factors
- The degree of burns correlates with outcomes 2
- Grade 0,1, and 2a injuries typically recover without sequelae
- Grade 2b and 3 injuries often develop esophageal or gastric strictures
- Voluntary ingestion and acid use are associated with greater severity of lesions 7
- Mortality rate of approximately 5-12% in severe cases 2, 7
Common Pitfalls
- Relying on symptoms alone to predict injury severity
- Delaying endoscopic evaluation beyond 48 hours
- Attempting to neutralize the caustic agent, which can generate heat and worsen injury
- Inducing vomiting, which increases risk of re-exposure and aspiration
Remember that the pattern of injury differs between acids and alkalis, with acids typically causing more severe gastric injury while still potentially affecting the esophagus. Early and appropriate evaluation with imaging and endoscopy is crucial for determining prognosis and management.