What is the initial management of smoke inhalation in the emergency room?

Initial Emergency Department Management of Smoke Inhalation Injury

All patients with suspected smoke inhalation should receive immediate high-concentration oxygen therapy (100% FiO2 via non-rebreather mask or mechanical ventilation for 6-12 hours), undergo rapid airway assessment with early intubation for any signs of compromise, and have hydroxocobalamin administration restricted only to cases with high suspicion of severe cyanide poisoning. 1, 2

Immediate Assessment and Recognition

Clinical Signs to Identify

• Airway compromise indicators: voice changes, stridor, laryngeal dyspnea, hoarseness, or dysphonia 2, 3
• Direct exposure signs: facial burns, soot on face/in nares/oropharynx, singed nasal hairs, carbonaceous or blackish sputum 2, 3, 4
• Respiratory distress: dyspnea, wheezing, polypnea, or increased work of breathing 2, 3
• History: entrapment in enclosed space during fire, loss of consciousness at scene 5

Initial Actions

• Remove all burning materials and flammable substances from the patient 2
• Cool thermal burns with clean running water for 5-20 minutes if external burns present 2
• Obtain IV access immediately for resuscitation fluids 6
• Monitor oxygen saturation, though recognize pulse oximetry can be falsely elevated in CO poisoning 2

Airway Management

Immediate Intubation Indications

Intubate without delay if any of the following are present: 2, 3, 7

• Severe hypoxia or hypercapnia
• Altered mental status or coma (GCS ≤8)
• Signs of airway obstruction (stridor, severe hoarseness)
• Severe respiratory distress
• Deep circular neck burns or extensive facial burns with TBSA ≥40% 3

Critical pitfall: Do not delay intubation when signs of airway compromise are present, as progressive edema can rapidly convert a manageable airway into a surgical emergency. 2, 6 Early intubation, preferably with fiberoptic bronchoscopy guidance, is prudent before airway edema develops. 6

For Patients Without Immediate Intubation Needs

• Close monitoring with frequent reassessment, as edema may develop progressively over hours 2
• Approximately 12% of smoke inhalation patients without burns require intubation versus 62% with concomitant burns 8

Oxygen Therapy

Administer 100% oxygen immediately to all patients with suspected smoke inhalation: 1, 2

• Via high-concentration non-rebreather mask if spontaneously breathing
• 100% FiO2 for 6-12 hours if mechanically ventilated
• Continue until carboxyhemoglobin levels normalize and symptoms resolve 3

This is the cornerstone of treatment regardless of pulse oximetry readings, which can be falsely reassuring in CO poisoning. 2

Carbon Monoxide and Cyanide Poisoning Management

Hydroxocobalamin Administration

Do NOT routinely administer hydroxocobalamin after smoke inhalation. 1, 2 Restrict to specific high-risk scenarios only:

Adults: Consider only with high suspicion of severe cyanide poisoning: 1, 2

• Cardiac or respiratory arrest
• Shock or coma
• Plasma lactate ≥8 mmol/L (83% of cyanide-poisoned patients have lactate >8 mmol/L) 1
• Dosing: 5g IV (10g for cardiac arrest) 1, 2

Children: Administer for moderate or severe cyanide poisoning signs: 1, 3

• Moderate: GCS ≤13, confusion, stridor, hoarse voice, polypnea, dyspnea, soot in airways 1, 3
• Severe: GCS ≤8, seizures, coma, mydriasis, severe hemodynamic instability, collapse, respiratory depression 1, 3
• Dosing: 70 mg/kg IV (maximum 5g) 1, 2, 3

Important caveat: Hydroxocobalamin has been associated with oxalate nephropathy, making routine administration potentially harmful. 1

Hyperbaric Oxygen Therapy (HBOT)

HBOT should NOT be routinely administered for suspected CO poisoning after smoke inhalation. 1, 2 The Cochrane systematic review found no evidence that HBOT decreases neurological sequelae of CO poisoning. 1

Consider HBOT only on a case-by-case basis for: 1, 2, 3

• Pregnant women with any CO exposure
• Patients with altered consciousness or coma
• Neurological, respiratory, cardiac, or psychological symptoms
• Children with impaired consciousness

Practical limitations: HBOT is often contraindicated in severe burns due to hemodynamic or respiratory instability, and technical difficulties carry significant risks. 1 Evaluation must consider patient stability, time to HBOT availability, and presence of specialized teams. 1

Diagnostic Evaluation

Bronchoscopy

• Perform flexible bronchoscopy at the burn center to assess severity of inhalation injury 2, 3
• Bronchoscopic findings correlate with morbidity, ICU length of stay, duration of mechanical ventilation, and hypoxemia severity 3
• Should not delay transfer to burn center if indicated 1

Laboratory Assessment

• Plasma lactate levels to guide cyanide poisoning suspicion (>8 mmol/L correlates with cyanide toxicity) 1, 2
• Carboxyhemoglobin levels (though treatment decisions should not wait for results) 2

Respiratory Support and Ventilation

• Mechanical ventilation with PEEP for pulmonary injury if intubated 8
• Lung protective ventilation strategies for patients requiring mechanical support 7
• Bronchial hygiene: therapeutic coughing, chest physiotherapy, deep breathing exercises, early ambulation 6
• Pharmacological adjuncts (at burn center): beta-2 agonists, racemic epinephrine, N-acetylcysteine, aerosolized heparin 6

Transfer to Specialized Care

Seek immediate referral to a burn center for: 2, 3

• Any smoke inhalation injury with suspected significant exposure
• Second- or third-degree burns involving face, hands, feet, or genitals
• Burns >5% body surface area in children
• TBSA ≥40% in adults

Direct admission to burn center is preferred over transfer through intermediate facilities, as it reduces time to definitive treatment and improves outcomes. 3 Consider telemedicine consultation if burn specialists are not readily available. 2

Critical context: Smoke inhalation increases mortality three-fold in children and raises mortality to 30-50% in burn patients (versus <10% in inhalation injury alone), emphasizing the importance of specialized care. 1, 3, 8

Pain Management

• Multimodal analgesia with titrated medications based on validated assessment scales 1
• Titrated IV ketamine can be combined with other analgesics for severe burn-induced pain 1
• Over-the-counter analgesics for pain control during transport 3

Follow-Up Care

All patients treated for acute CO poisoning require clinical follow-up at 1-2 months post-event to assess for delayed neurological sequelae, including memory disturbance, depression, anxiety, vestibular problems, and motor dysfunction. 2, 3