View source for Smoke inhalation injury

==Background==
*Main cause of mortality in fire-related death
*Associated with closed-space fires, especially when patient has decreased mental status (e.g. substance use, head injury)
*Thermal injury: 
**Due to inhaling superheated gases in an enclosed space
**Direct thermal trauma and associated edema usually limited to upper airway, but lower respiratory tract may be injured if steam inhaled
*Chemical injury:
**Direct toxicity to airways and lung parenchyma from noxious chemicals combusted

==Clinical Features==
===Thermal injury===
*Soot around nares or in mouth
*Carbonaceous sputum
*Singed nasal or facial hair
*[[Dyspnea]], [[stridor]], drooling, [[dysphonia]], [[respiratory distress]]

===Chemical injury===
''Varies depending on substance burned in fire''
*Acrolein: found in wood and petroleum
**[[Pulmonary edema]], bronchorrhea, bronchospasm, VQ mismatch which can cause [[hypoxemia]]
**Tearing, [[conjunctivitis]]
*[[Hydrochloric acid]]: product of polyvinyl chloride (structural component of high-rise buildings, plastics) combustion. 
**Can persist in air up to an hour after fire extinguished
**PVCs and other [[arrhythmias]]
**Delayed onset (2-12 hours) [[pulmonary edema]]
**[[Dyspnea]], [[chest pain]]
*Tuolene diisocyanate: seat cushions, carpet, insulation
**Severe bronchospasm
*Nitrogen dioxide: fires involving automobiles, agrecultural waste
**Uncommon but brief exposure can be lethal
**Severe bronchospasm, laryngospasm, [[pulmonary edema]]
**Later: [[interstitial lung disease]]

===Systemic chemical injury===
*[[Carbon monoxide toxicity]]
*[[Cyanide toxicity]]

==Differential Diagnosis==
{{Burn DDX}}
{{Inhalation exposure}}
{{Toxic gas exposure DDX}}

==Evaluation==
*Assess ABCs, [[burns]] resuscitation
*[[ABG]] or VBG, carboxyhemoglobin
*[[ECG]], monitor on telemetry
*[[Chest x-ray]]
*Low threshold for direct or video [[laryngoscopy]], fiberoptic airway eval

==Management==
'''AIRWAY'''
*[[Intubate]] if:
**Respiratory distress, respiratory depression, or altered mental status
**Progressive hoarseness
**Supraglottic or laryngeal edema/inflammation on bronchoscopy or NPL
**Full thickness burns to face or perioral region
**Circumferential neck burns
**Major burns over 40-60% of [[Estimating body surface area|body surface area]]
''Remember, the intubation will only get more difficult as edema worsens!''
*[[Bronchodilators]] if evidence of bronchospasm
*See [[Carbon monoxide toxicity]]
*See [[Cyanide toxicity]]

==Disposition==
* Respiratory distress or airway compromise will need admission
* Observe for 1-4 hours if no signs or symptoms of inhalation injury develop or if all resolved within 1 hour consider discharging patient home with instructions for return for re-evaluation next day or sooner if pulmonary and/or airway symptoms develop

==See Also==
*[[Inhalation injury]]
*[[Burns]]
**[[Carbon monoxide toxicity]]
**[[Cyanide toxicity]]
*[[Intubation]]

==External Links==

==References==
<references/>

[[Category:Trauma]]
[[Category:Pulmonary]]