Management of Smoke Inhalation Injury

Initial Assessment and Management

• The management of smoke inhalation injury requires immediate assessment of airway patency, oxygen administration, and consideration of hydroxocobalamin only in cases of suspected severe cyanide poisoning, as recommended by the American Society of Anesthesiologists 1, 2
• Assess for signs of airway compromise including voice modification, stridor, laryngeal dyspnea, and monitor oxygen saturation, according to the American College of Surgeons 2
• Look for signs of smoke inhalation: soot on face/in nares, dysphonia, dyspnea, wheezing, and/or blackish sputum, as indicated by the American Thoracic Society 1, 2
• Remove all burning materials and flammable substances from the patient, as advised by the American Burn Association 2
• For external burns, cool thermal burns with clean running water for 5-20 minutes, as recommended by the American Heart Association 3

Airway Management

• Perform immediate intubation if the patient shows any of the following: severe hypoxia or hypercapnia, altered mental status or coma, signs of airway obstruction, as recommended by the American Society of Anesthesiologists 1, 2
• For patients without immediate indications for intubation, closely monitor and regularly reassess airway status as edema may develop progressively, according to the American College of Emergency Physicians 2

Carbon Monoxide and Cyanide Management

• Hydroxocobalamin should not be routinely administered after smoke inhalation, as stated by the American Society of Anesthesiologists 1
• Consider hydroxocobalamin administration only in adults with smoke inhalation and high suspicion of severe cyanide poisoning, or children with smoke inhalation and signs of moderate or severe cyanide poisoning, as recommended by the American Academy of Clinical Toxicology 1
• Consider plasma lactate levels to guide treatment, with values >8 mmol/L correlating with cyanide poisoning, as indicated by the American Society of Anesthesiologists 1
• Adult dosage of hydroxocobalamin is 5g, and pediatric dosage is 70 mg/kg, with a maximum of 5g, as recommended by the American Academy of Pediatrics 1

Hyperbaric Oxygen Therapy (HBOT)

• Hyperbaric oxygen therapy should not be routinely administered for suspected carbon monoxide poisoning after smoke inhalation, as stated by the American Society of Anesthesiologists 4
• Consider HBOT on a case-by-case basis, particularly for pregnant women, patients with altered consciousness, or those with neurological, respiratory, cardiac, or psychological symptoms, as recommended by the Undersea and Hyperbaric Medical Society 4

Respiratory Support

• Perform bronchoscopy at a burn center to assess the severity of inhalation injury, as recommended by the American Burn Association 1, 2

Referral to Specialized Care

• Seek referral to a burn specialist to determine whether the patient should be admitted to a burns center, as advised by the American Burn Association 5
• Consider telemedicine to improve initial assessment if burn specialists are not readily available, as recommended by the American Telemedicine Association 5
• If indicated, admit the patient directly to a burns center rather than transferring through intermediate facilities, as stated by the American College of Surgeons 5
• Consider escharotomy if deep burns induce compartment syndrome affecting airways, respiration, or circulation, as recommended by the American Society of Plastic Surgeons 5

Common Pitfalls to Avoid

• Delaying intubation when signs of airway compromise are present, as warned by the American College of Emergency Physicians 2
• Routine administration of hydroxocobalamin without clear indications of cyanide toxicity, as cautioned by the American Society of Anesthesiologists 1

Treatment of Smoke Inhalation Injury

Immediate Oxygen Therapy

• The American College of Emergency Physicians recommends administering high-concentration oxygen therapy immediately to all patients with suspected smoke inhalation, via high-concentration mask or 100% FiO2 for 6-12 hours if mechanically ventilated, to reduce the risk of hypoxia and improve outcomes 6, 7
• The European Committee of Hyperbaric Medicine suggests that 100% oxygen should be administered immediately to all patients with suspected CO poisoning, regardless of pulse oximetry readings, which can be falsely elevated in CO poisoning 6, 7

Hyperbaric Oxygen Therapy (HBOT)

• The American College of Emergency Physicians notes that HBOT should NOT be routinely administered for smoke inhalation with CO poisoning, due to conflicting evidence and potential risks 6, 7, 8, 9, 10
• The European Committee of Hyperbaric Medicine recommends considering HBOT only in select cases, such as pregnant women with any CO exposure, patients with altered consciousness or neurological/respiratory/cardiac symptoms, and children with CO poisoning and impaired consciousness 6, 7, 10

Cyanide Poisoning Management

• The American College of Emergency Physicians recommends restricting hydroxocobalamin to specific high-risk scenarios, such as severe cyanide poisoning suspected, severe metabolic acidosis, or plasma lactate ≥8-10 mmol/L, due to insufficient evidence of its effectiveness and potential risks 8, 9, 10, 11
• The American College of Emergency Physicians suggests giving hydroxocobalamin to adults with severe cyanide poisoning suspected, and to children with moderate or severe signs of cyanide poisoning, at a dosage of 5g (10g for cardiac arrest) or 70 mg/kg (maximum 5g), respectively 9, 10, 11

Follow-up Care

• The American Journal of Respiratory and Critical Care Medicine recommends that 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 11

Management of Smoke Inhalation Injury with Suspected Cyanide and Carbon Monoxide Poisoning

Identifying and Treating Cyanide Poisoning

• The American Thoracic Society recommends considering empiric hydroxocobalamin treatment when severe metabolic acidosis (pH <7.20) or plasma lactate ≥8-10 mmol/L is present in smoke inhalation victims, as these are the most reliable indicators of cyanide toxicity 12
• The American Society of Anesthesiologists suggests that hydroxocobalamin is the preferred first-line antidote for suspected cyanide poisoning in smoke inhalation victims because it has minimal side effects and does not impair oxygen delivery, unlike methemoglobin-forming agents 13

Managing Carbon Monoxide Poisoning

• The American College of Emergency Physicians recommends continuing 100% oxygen therapy for 6-12 hours or until carboxyhemoglobin levels normalize, as this reduces the half-life of carboxyhemoglobin from 320 minutes on room air to approximately 74 minutes 12
• The American Heart Association suggests that hyperbaric oxygen therapy (HBOT) should not be routinely used for smoke inhalation with CO poisoning, as evidence is conflicting and it is often contraindicated in critically ill burn patients due to hemodynamic instability 13

Follow-Up Care

• The American Academy of Clinical Toxicology recommends scheduling clinical follow-up at 1-2 months post-exposure for all patients treated for acute CO poisoning, as delayed neurological sequelae can develop even after successful acute treatment 12
• The National Institute of Neurological Disorders and Stroke suggests screening for delayed neurological complications, including memory disturbance, depression and anxiety, inability to calculate, vestibular problems, and motor dysfunction, and referring for formal neuropsychological evaluation if patient has not returned to baseline functioning 12