What is the recommended management for inhalation of alkaline caustic substances?

Management of Alkaline Fluid Inhalation

Immediate Airway Assessment and Stabilization

Airway assessment is the absolute first priority in alkaline inhalation injury, with immediate evaluation for signs of impending airway obstruction including hoarseness, dysphagia, drooling, wheeze, stridor, dyspnea, or desaturation—any of which mandate urgent intubation. 1

Clinical Features Requiring Urgent Intubation

• Dyspnea, desaturation, and stridor are absolute indications for urgent intubation 1
• Voice modification, laryngeal dyspnea, or stridor indicate glottic edema requiring immediate airway control 1
• Respiratory distress or severe hypoxia mandate intubation without delay 1
• Concomitant vapor aspiration from alkaline substances (particularly ammonia) causes direct airway burns requiring aggressive airway management 1

Intubation Technique

• Modified rapid sequence intubation (RSI) is the most appropriate technique for alkaline inhalation injury 1
• Use videolaryngoscopy when available, as it increases intubation success with minimal airway trauma 1
• Use an uncut tracheal tube to allow for subsequent facial and airway swelling 1
• Avoid succinylcholine from 24 hours post-injury onward to prevent hyperkalaemia 1
• Insert a gastric tube after securing the airway, as this may become difficult later 1

Conservative Management for Stable Patients

If urgent intubation is not indicated, patients must be observed in a high-dependency area, nursed head-up, kept nil-by-mouth, with regular reassessment to detect deterioration early. 1

Monitoring Strategy

• Nasendoscopy can be performed to assess mucosal appearance; normal findings are reassuring and can be repeated at intervals 1
• Clinical signs lack sensitivity and are unreliable predictors of the requirement for intubation 1
• Regular reassessment is mandatory as airway swelling can progress over the first 24-48 hours 1

Critical Pitfall

• Large volume fluid resuscitation will worsen airway swelling and should be avoided unless absolutely necessary 1

Bronchoscopic Management

Frequent bronchoscopy is useful to assess injury severity, remove debris and casts, and potentially avoid intubation in selected cases. 2

Therapeutic Bronchoscopy

• Prompt bronchoscopic diagnosis and suctioning to remove epithelial debris, fibrin clots, and inspissated mucus improves outcomes 3
• Nebulized heparin for fibrin casts and nebulized N-acetylcysteine for mucus casts are supported by available data 3
• Bronchodilators should be used to manage bronchospasm 3

Systemic Considerations

Alkaline substances cause liquefactive necrosis allowing deeper tissue penetration, and specific alkaline agents may cause severe systemic effects requiring monitoring. 4

Ammonia-Specific Management

• Ammonia inhalation results in high morbidity and can cause severe inhalation injury with both upper airway and bronchoalveolar involvement 2, 5
• Ammonia has high water solubility leading to immediate reactions with mucous membranes and rapid symptom onset 5
• Aggressive pulmonary toilet and lung-protective ventilator strategies are essential 5

Laboratory Monitoring

• Obtain CBC, electrolytes (particularly sodium, potassium, calcium, magnesium), renal function, liver function tests, arterial pH, and serum lactate 1
• Specific alkaline corrosives may cause hypocalcemia, hyponatremia, hypokalemia, and acidosis 1

Specialist Consultation

Obtain specialist advice early from a burns center, as the decision to intubate early versus manage conservatively is complex and requires senior decision-making. 1

Long-Term Sequelae

• A proportion of patients develop airway stenosis requiring aggressive treatment or even surgery due to persistent necrotic shedding and scarring contracture 6
• Hyperreactive bronchoconstrictive components and peripheral airway disease may persist long-term 7
• Regular follow-up is essential to monitor for delayed complications 6