Nursing care
Smoke Inhalation Injury nursing care: what to assess and what to do first
Written and reviewed by Dana Whitfield, RN, MSN · 5 min read · Updated September 2026
Short answer
Smoke inhalation injury damages the airway and lungs through heat, chemical irritants, and asphyxiant gases carried in smoke. Singed nasal hair, soot around the mouth or nose, and a hoarse voice are warning signs that the airway will swell and close over the following hours, even if the patient looks stable now. These findings call for early intubation, before obstruction makes it impossible.
Recognising it at the bedside
Look first at the face and airway, not the chest. Singed facial or nasal hair, soot in the sputum, mouth, or nostrils, and a hoarse or brassy voice are the classic triad pointing to thermal and chemical injury above the vocal cords. A history of being trapped in an enclosed, smoky space raises suspicion regardless of how the patient currently sounds.
Below the cords, expect a productive cough with carbonaceous sputum, wheezing or stridor, and tachypnoea as the lower airways react to soot particles and toxic combustion products such as cyanide and carbon monoxide. Facial burns and singed eyebrows often accompany inhalation injury but the inhalation component is what kills faster than the skin burns do.
Why the classic presentation misleads
A patient who can still speak clearly and has an SpO2 in the high 90s in the first hour after exposure looks reassuring, and that is exactly the danger. Airway oedema from thermal and chemical injury develops progressively over the following 12 to 24 hours, not instantly. By the time stridor or visible distress appears, the airway may already be too swollen for an easy intubation.
Pulse oximetry is also unreliable here for a second reason beyond the airway: carbon monoxide bound to haemoglobin reads as saturated on standard pulse oximetry, so a normal-looking SpO2 can coexist with significant carboxyhaemoglobin poisoning. A stable-looking patient with a clean-sounding voice can still be hours from a closed airway and carrying a toxic CO load neither the oximeter nor a calm demeanour will reveal.
Priority nursing actions
Any patient with singed nasal hair, oral or nasal soot, or a change in voice quality after smoke exposure should be treated as a probable airway at risk, and early intubation should be anticipated and prepared for rather than waiting for stridor to confirm it. Assemble airway equipment, have suction ready, and alert the provider immediately with these specific findings rather than a general 'patient exposed to smoke' report.
Give 100% humidified oxygen via non-rebreather regardless of the pulse oximetry reading, since the reading cannot rule out carbon monoxide or cyanide toxicity. Obtain a carboxyhaemoglobin level and an ABG with co-oximetry, not a standard ABG alone. Monitor voice, work of breathing, and secretions continuously, and reassess airway status at short, defined intervals rather than once at triage. If burns are also present, address airway before fluid resuscitation calculations, since an unsecured airway kills faster than burn shock.
Labs and diagnostics to expect
Carboxyhaemoglobin level is essential and must be drawn early, since it falls over time with oxygen therapy and a delayed sample understates the peak exposure. An ABG with co-oximetry gives an accurate oxygen saturation, unlike standard pulse oximetry, and can also flag metabolic acidosis suggestive of cyanide toxicity.
Expect fibreoptic bronchoscopy to directly visualise the airway and lower tracheobronchial tree for erythema, oedema, soot, or mucosal sloughing — this is often more decisive than clinical signs alone in deciding whether to intubate. A chest X-ray is frequently normal in the first hours even with significant injury, so a clear film should not be used to rule out inhalation injury. Serial ABGs and lactate trend help track evolving hypoxia and tissue perfusion as the injury progresses.
Complications and their early signs
Upper airway obstruction from progressive oedema is the earliest life-threatening complication, signalled by stridor, drooling, inability to handle secretions, or a voice that becomes progressively more muffled. This can evolve over hours, which is why a one-time airway assessment is never sufficient.
Later complications include acute respiratory distress syndrome from chemical injury to the alveoli, pneumonia from impaired mucociliary clearance and soot-laden airways, and bronchospasm mimicking an asthma exacerbation. Cyanide toxicity should be suspected with persistent lactic acidosis and cardiovascular instability disproportionate to the apparent burn size, particularly after exposure to burning synthetic materials or plastics.
Teaching that changes outcomes
Before discharge, teach the patient and family to recognise delayed voice changes, increasing work of breathing, or new cough as reasons to return immediately, since airway swelling and lower airway inflammation can worsen after the initial event has passed and the patient has been observed as stable.
Reinforce home fire safety specific to what caused the exposure — working smoke detectors, an escape plan, and closing doors behind them when evacuating to slow smoke spread. For patients being discharged after a milder exposure, explain that a normal-sounding voice and normal oxygen saturation at discharge do not exclude ongoing lower airway inflammation, and that follow-up for pulmonary function assessment may be advised depending on exposure severity.
The next step on this is the same as on everything else here: answer questions and read the rationales. Our respiratory practice questions are the closest set to what this page covers.
Common questions
What are the earliest warning signs of smoke inhalation injury?
Singed nasal or facial hair, soot around the mouth or nostrils, a hoarse or brassy voice, and a history of enclosed-space smoke exposure are the earliest red flags. These findings predict airway swelling that has not yet occurred, so they justify preparing for intubation before stridor or distress develops.
Why is pulse oximetry unreliable in smoke inhalation injury?
Standard pulse oximetry cannot distinguish oxyhaemoglobin from carboxyhaemoglobin, so a patient with significant carbon monoxide poisoning can show a normal or near-normal SpO2. An ABG with co-oximetry, plus a specific carboxyhaemoglobin level, is needed to see the true picture.
When should a patient with smoke exposure be intubated?
Intubation should be considered early, based on singed nasal hair, oral soot, voice change, or bronchoscopic evidence of airway oedema, rather than waiting for stridor or visible respiratory distress. Airway swelling progresses over hours, and delaying until obstruction is obvious can make intubation far more difficult or impossible.
How does smoke inhalation injury typically appear on the NCLEX?
Expect a scenario describing a fire victim with singed nasal hair, soot in the mouth, and a hoarse voice, asking you to select the priority action — usually preparing for early intubation rather than reassurance based on a normal SpO2 or calm appearance. Questions may also test recognition that a normal chest X-ray does not rule out inhalation injury.
What should be given immediately for suspected smoke inhalation, before test results return?
High-flow humidified oxygen via non-rebreather mask should be started immediately, regardless of pulse oximetry reading, because it cannot be trusted to reflect true oxygenation or carbon monoxide load in this population. Airway equipment should be at the bedside in case rapid intubation becomes necessary.