Corrosive injuries of the oesophagus Flashcards
What is the definition of corrosive injuries of the oesophagus
Tissue injury induced by chemical reaction on the oesophageal wall
Also referred to as caustic injuries/burns/ingetsion
Explain the epidemiology of corrosive injuries of the oesophagus
1st Peak: 1-5years
- Mostly ingested accidently
2nd Peak: 21years and older
- Suicidal and intentional, often more severe
- Inflicted by others: Spiked drinks
- Accidental
Which areas in the oesophagus are prone to caustic injury
3 areas of narrowing
- Upper Oesophageal sphincter
- Aorta makes an indentation
- Lower Oesophageal sphincter
Explain the pathophysiology of caustic injury
Caustic injury are caused by strong acid and strong alkali
Severity is determined by type, amount, concentration and duration
What are the possible extent of injuries of caustic injuries
Ingested corosives may affect any part of the aero digestive tract they come into contact with. From lips down to upper small intestine
Immediate threat is involvement of airway
Explain Solid lye injuries
Critical pH: >11
Lye is general term for alkali cleaning problems
Solid lye: crystals
- Tend to stick to mucosa
- Deep burns where they adhere
- Rarely cause injury beyond the oropharynx and proximal oesophagus
Explain liquid lye injuries
Easily swallowed and quickly cover the entire oesophagus and move into the stomach. Injury ccurs quickly within seconds to minutes
3 phases:
- 1st phase: Liquefactive necrosis 1 to 5 days.
- 2nd phase: Reparative phase: Begins from 5th day, Development of granulation tissue
- 3rd phase: Scar retraction in both longitudal and circumferetial direction resulting in oesophageal shortening and stricture formation
Explain acid injuries
Causes coagulative necrosis
Coagulum helps to limit penetration into deeper layers
Oesophagus is often spared or mildly damaged
Stomach is commonly involved, pooling of acid in the stomach and pyloric spasm
Explain the classification of caustic injury of the mucosa
Grade 0: Normal mucosa
Grade 1: Edema and erthema of mucosa
Grade 2A: Hemorrhage, erosions, blisters, superficial ulcres
Grade 2B: Circumferential lesions
Grade 3A: Focal deep gray or brownish black ulcers
Grade 3B: Extensive deep gray or brownish black ulcers
Grade 4: Perforation
What are the complications of caustic injuries of the oesophagus
Airway obstruction
Bleeding
Perforation
Stricture formation
Oesophageal carcinoma
What are the clinical presentation of caustic injury
History
Symptoms:
- Oropharyngeal pain, odynophagia
- Dysphagia
- Drooling of saliva
- Breathing difficulty
- Retrosternal or epigastric pain
What are the important signs of caustic injury during examination
Respiratory signs:
- Stridor
- Bronchospasm
General condition
- Shock
- Abdominal signs: Tenderness and peritonitis
What are the investigations for caustic injury of the oesophagus
Blood gas analysis
Urea and electrolytes/full blood count/CRP
Chest xrays - look for signs of aspiration of perforation
Endoscopic ultrasound - shows different layers of oesophagus
CTscan - can show depth of necrosis and transmural damage
What is the management of caustic injuries of the oesophagus
ABC principles of resuscitation
- Airway: Patient may need intubation
Supportive management:
- Intravenous lines and fluids
- Pain control
- Keep patient NPO
Management of complications
What are the precautions of management for caustic injuries of the oesophagus
Avoid induced emesis: Do not induce vomiting
- Further exposes the oesophagus to damage by the corrosive agent
Avoid acid neutralisation
- Causes an exothermic reaction and further damage to the oesophagus
Antibiotics
- Not routinely given unless there is perforation
Streroids:
- Controversial
Nasogastric tubes:
- Tend to indice retching and further injury to oesophagus
- Rather avoid until assessment by endoscopy