What is the management of acid fume inhalation?

Management of Acid Fume Inhalation

Immediately remove the patient from the exposure source, ensure airway patency, and administer 100% oxygen while assessing for respiratory distress and systemic toxicity.

Immediate Scene Safety and Decontamination

• Remove the patient from the contaminated environment immediately to prevent continued exposure 1
• Remove all contaminated clothing and jewelry to stop ongoing chemical contact 2
• Wear appropriate protective equipment (gloves, respiratory protection) when handling the patient or contaminated materials to avoid secondary exposure 1
• If eye exposure occurred, flush eyes immediately with copious amounts of tepid water for at least 15 minutes 2
• Avoid public transportation; use ambulance or private vehicle with windows open for ventilation 2

Airway Assessment and Management

The critical decision is whether immediate intubation is required, as acid fume inhalation can cause rapid airway compromise.

Indications for Immediate Intubation:

• Severe respiratory distress with hypoxia or hypercapnia 1
• Altered mental status or coma 1
• Stridor or signs of upper airway obstruction 1
• Inability to protect airway 1
• Severe facial burns or oropharyngeal edema 1

If Not Immediately Intubated:

• Monitor continuously for deterioration, as pulmonary edema can be delayed 3, 4
• Reassess frequently during transport and after hospital admission 1
• Be prepared for difficult intubation if airway edema develops 1

Oxygen Therapy

• Administer 100% oxygen immediately via non-rebreather mask to all patients with suspected toxic inhalation 5, 6
• Do not wait for laboratory confirmation before initiating oxygen therapy 5
• Titrate to maintain oxygen saturation ≥90% 1
• If CO₂ retention occurs with acidemia, consider noninvasive or invasive mechanical ventilation rather than reducing oxygen 1

Assessment for Specific Toxicities

Cyanide Poisoning (if exposure from fire/combustion):

• Measure plasma lactate; levels >8 mmol/L suggest cyanide poisoning 1
• Administer hydroxocobalamin 5 g IV (10 g for cardiac arrest) in adults if severe cyanide poisoning suspected with cardiac arrest, shock, or coma 1
• In children: hydroxocobalamin 70 mg/kg (maximum 5 g) for moderate-to-severe signs 1
• Do NOT give hydroxocobalamin routinely to all acid fume inhalation patients 1

Carbon Monoxide Poisoning (if exposure from fire):

• Measure carboxyhemoglobin (COHb) levels 5
• Continue 100% oxygen regardless of COHb level 5
• Consider hyperbaric oxygen therapy (HBOT) for: loss of consciousness, neurological deficits, ischemic cardiac changes, significant metabolic acidosis, or COHb >25% 5
• HBOT is NOT routinely indicated for isolated acid fume inhalation without CO exposure 1

Respiratory Support

For Pulmonary Edema/ARDS:

• Acid fume inhalation commonly causes noncardiogenic pulmonary edema from direct alveolar injury 3, 4, 7
• Provide mechanical ventilation with lung-protective strategies if ARDS develops 3, 4
• Consider advanced therapies (ECMO, inhaled nitric oxide, surfactant) for refractory cases, though outcomes remain poor 3
• No specific antidote exists for direct chemical pulmonary injury 7

Bronchodilators:

• Administer short-acting β-agonists (albuterol) and ipratropium via MDI with spacer or nebulizer for bronchospasm 1

Corticosteroids:

• Corticosteroids are frequently used but efficacy is not proven for chemical pulmonary injury 7
• If used, consider prednisone 30-40 mg daily orally or equivalent IV dose 1

Monitoring and Diagnostic Evaluation

• Obtain arterial blood gas to assess oxygenation, ventilation, and acid-base status 1
• Chest X-ray (may be initially normal; pulmonary edema can be delayed) 4, 7
• Continuous pulse oximetry and cardiac monitoring 1
• Bronchoscopy should NOT be performed in the field or emergency department as it may worsen respiratory status and delay transfer to specialized care 1
• If bronchoscopy is needed, perform only after intubation in a controlled setting 1

Critical Pitfalls to Avoid

• Do not underestimate delayed pulmonary edema: Patients may present with minimal symptoms initially but develop fulminant respiratory failure hours later 3, 4
• Do not delay oxygen therapy while awaiting diagnostic tests 5
• Do not assume mild initial symptoms mean benign course; acid fume inhalation can progress to ARDS requiring mechanical ventilation 8
• Do not perform bronchoscopy outside specialized centers as it delays definitive care 1
• Recognize that even with maximal therapy including ECMO, mortality from severe acid inhalation can be very high 3

Disposition and Follow-up

• Admit all patients with significant exposure for observation, as pulmonary edema may be delayed up to 24-48 hours 3, 4, 7
• Transfer to burn center or tertiary care facility for severe cases 1
• Follow-up at 1-2 months to assess for chronic sequelae: bronchiectasis, chronic airflow obstruction, bronchial hyperreactivity, or reactive airways dysfunction syndrome 5, 7
• Most patients recover with little residual dysfunction, but disabling long-term sequelae can occur 7