Browse categories and answer follow-up questions to refine your symptom profile.
History
Exposure details
Exposure timeline and setting
Enclosed space exposure
Duration of exposure
Time since last exposure
Source material
Structural fire smoke
Wildfire smoke
Chemical smoke
Explosion
Loss of consciousness
Estimated proximity to flame
Rescue details
Self extricated
Found down
Required CPR
Co exposed individuals
Other symptomatic contacts
Pets affected
Presenting symptoms OPQRST
Symptom characterization
Primary symptom
Dyspnea
Cough
Chest tightness
Sore throat
Hoarseness
Associated symptoms
Wheeze
Stridor
Sputum
Carbonaceous sputum
Headache
Dizziness
Nausea
Confusion
Syncope
Seizure
Chest pain
O onset
Sudden onset
Gradual onset
Delayed onset after exposure
P provocation and palliation
Worse with exertion
Worse when supine
Relief with oxygen
Q quality
Burning throat
Tightness
Irritative cough
R region and radiation
Upper airway symptoms
Lower chest symptoms
S severity
Dyspnea at rest
Dyspnea on exertion
Speech limitation
T timing
Progressive symptoms
Improving symptoms
Episodic symptoms
Baseline and prior episodes
Baseline respiratory and neurologic status
Baseline exercise tolerance
Baseline oxygen requirement
Prior smoke inhalation
Prior CO exposure
Prior asthma exacerbations
Prior COPD exacerbations
Alarm Features
Immediate airway and respiratory threats
High risk airway features
Stridor
Voice change
Drooling
Inability to handle secretions
Progressive facial or neck swelling
Oropharyngeal blistering
Extensive facial burns
Shock and end organ threat
High risk vital sign patterns
SpO2 below 90 percent on room air
Respiratory rate 30 or higher
Systolic BP below 90 mmHg
Heart rate 130 or higher
Temperature 38.5 C or higher
GCS 14 or less
Toxic exposure red flags
CO and cyanide red flags
Altered mental status
Syncope
Seizure
Severe metabolic acidosis
Lactate 10 mmol per L or higher
Hemodynamic instability despite oxygen
Escalation triggers
Immediate escalation logic
If impending airway compromise then early intubation
If persistent hypoxemia on high flow oxygen then ventilatory support
If suspected cyanide toxicity with shock or lactate 10 mmol per L or higher then antidote per protocol
Medications
Current medications and interactions
Medication reconciliation relevance
Inhaled bronchodilators
Inhaled corticosteroids
Systemic steroids
Beta blockers
Sedatives
Opioids
Anticoagulants
Antiplatelets
High risk medication considerations
Medication related risks
Chronic opioid use
Hypoventilation risk
Higher aspiration risk
Benzodiazepines
Delirium risk
Respiratory depression risk
Warfarin or DOAC
Airway bleeding risk with instrumentation
Trauma related bleeding risk
Treatment medication contraindication screen
Contraindications to common therapies
Nebulized beta agonist caution
Significant tachyarrhythmia
Severe ischemic chest pain
Systemic steroid caution
Active uncontrolled infection concern
Poorly controlled diabetes
Hyperbaric contraindication prompts
Untreated pneumothorax
Inability to equalize pressure
Diet
Intake and hydration
Recent intake status
Poor oral intake
Vomiting
Dehydration risk
Aspiration risk
Inhalational exposure modifiers
Recent exposures
Alcohol use around exposure
Smoking or vaping baseline
Recent inhaled drug use
Occupational smoke or fumes exposure
Review of Systems
Respiratory and ENT
Airway and breathing symptoms
Dyspnea
Wheeze
Stridor
Cough
Hemoptysis
Sore throat
Hoarseness
Dysphagia
Neurologic and systemic
Neuro and constitutional symptoms
Headache
Dizziness
Confusion
Syncope
Seizure
Weakness
Fever
Chills
Cardiovascular and GI
Cardiac and GI symptoms
Chest pain
Palpitations
Nausea
Vomiting
Abdominal pain
Collateral History and Family History
Collateral and scene information
Collateral reliability
EMS report
Fire service report
Bystander report
Family report
Family history relevant to risk
Family history
Premature coronary artery disease
Sudden cardiac death
Inherited anemia or hemoglobinopathy
Malignant hyperthermia history
Risk Factors
Patient factors increasing severity
High risk patient groups
Age 65 years or older
Pregnancy
Chronic lung disease
Asthma
COPD
Interstitial lung disease
Coronary artery disease
Heart failure
Anemia
Chronic kidney disease
Immunocompromised state
Exposure and environmental risks
Exposure features increasing toxicity
Enclosed space fire
Prolonged exposure time
Found down
Synthetic material combustion
Industrial chemical exposure
Airway edema and delayed deterioration risks
Predictors of airway compromise
Facial burns
Neck burns
Oropharyngeal burns
Soot in mouth or nose
Hoarseness
Stridor
Need for large volume resuscitation
Thrombosis and bleeding risks
Co morbid risks
Active anticoagulation
Recent surgery or trauma
Prior VTE history
Differential Diagnosis
Life threatening
Life threatening causes
Upper airway thermal injury with obstruction
Rapidly progressive stridor
Oropharyngeal burns
Carbon monoxide poisoning (T58)
Headache with exposure
Altered mental status
Ischemic ECG changes
Cyanide poisoning (T65.0)
Shock
Severe lactic acidosis
Acute respiratory failure (J96.00)
Persistent hypoxemia
Hypercapnia
ARDS (J80)
Bilateral infiltrates
High oxygen requirement
Inhalation associated bronchospasm with impending fatigue
Rising CO2
Exhaustion
Burn associated inhalation injury with systemic toxicity (T27)
Enclosed space fire
Carbonaceous sputum
Pneumothorax related to blast or barotrauma (J93.9)
Unilateral decreased breath sounds
Pleuritic chest pain
Common
Common causes
Smoke induced bronchitis
Cough
Normal imaging early
Asthma exacerbation (J45.901)
Wheeze
Triggered by irritant smoke
COPD exacerbation (J44.1)
Increased dyspnea
Increased sputum
Chemical irritant exposure without burns
Burning eyes
Throat irritation
Anxiety or panic reaction (F41.0)
Paresthesias
Normal oxygenation
Less common
Less common and mimics
Aspiration pneumonitis (J69.0)
Vomiting
New focal infiltrate
Pneumonia (J18.9)
Fever
Focal consolidation
Acute coronary syndrome (I21.9)
Chest pain
Troponin elevation
Toxic inhalation pneumonitis from specific chemicals (T59)
Delayed pulmonary edema
Exposure specific odor history
Past Medical History
Respiratory and cardiac history
Relevant chronic disease history
Asthma
Prior ICU admission
Prior intubation
COPD
Baseline home oxygen
Baseline hypercapnia history
Obstructive sleep apnea
Home CPAP use
Opioid sensitivity history
Coronary artery disease
Prior MI
Prior PCI or CABG
Heart failure
Baseline EF
Baseline diuretic use
Other relevant history
Other comorbidities and procedures
Diabetes mellitus (E11.9)
Chronic kidney disease (N18.9)
Seizure disorder (G40.909)
Prior airway surgery
Prior tracheostomy
Psychiatric disease with self harm risk
Baseline functional status
Functional baseline
Baseline ADL independence
Baseline mobility
Caregiver support reliability
Physical Exam
General and vital signs interpretation
General assessment
Work of breathing
Ability to speak full sentences
Mental status
Signs of distress
Vital sign patterns
Hypoxemia on room air
Tachypnea
Fever
Hypotension
Tachycardia
Airway and ENT
Upper airway exam
Facial burns
Singed nasal hairs
Soot in nares
Soot in oropharynx
Oral burns
Uvular edema
Tongue swelling
Hoarseness
Stridor
Pulmonary and chest
Lung exam
Wheeze
Crackles
Diminished breath sounds
Prolonged expiratory phase
Accessory muscle use
Chest wall and burn survey
Circumferential chest burns
Restrictive chest excursion
Associated trauma signs
Cardiovascular and perfusion
Perfusion and hemodynamics
Capillary refill delay
Cool extremities
New murmur
Dysrhythmia
Neurologic
Neurologic status
GCS
Focal deficits
Ataxia
Agitation
Seizure activity
Skin
Burn and exposure findings
Total body surface area estimate prompt
Burn depth prompt
Cyanosis
Cherry red skin prompt
Urticaria or angioedema signs
Lab Studies
Core labs for inhalation toxicity
Initial laboratory evaluation
Venous blood gas or arterial blood gas
pH trend for acidosis
PaCO2 for ventilatory failure
PaO2 for hypoxemia
Co oximetry
Carboxyhemoglobin level
Methemoglobin level
Lactate
Cyanide toxicity support if markedly elevated
Trend with resuscitation
CBC
Leukocytosis for infection or stress
Hemoglobin for anemia risk
CMP
Creatinine for renal dosing
AST ALT for hypoxic injury
Troponin
Myocardial ischemia from CO exposure
Serial testing if symptoms or ECG changes
Point of care testing and pitfalls
Diagnostic limitations
Pulse oximetry limitation with CO exposure
Normal PaO2 does not exclude CO poisoning
Early imaging may be normal despite inhalation injury
Infection and aspiration evaluation
When fever or focal findings
Blood cultures
Sputum culture
Procalcitonin local protocol dependent
Viral testing local protocol dependent
Imaging
Scoring Systems
Severity tools and structured assessment
CO poisoning severity markers
Neurologic symptoms
Cardiac ischemia
Pregnancy
High carboxyhemoglobin
Cyanide toxicity markers
Lactate 10 mmol per L or higher in enclosed space fire
Shock not responding to oxygen
Burn inhalation injury structured approach
Enclosed space exposure
Soot in airway
Facial burns
MRI
MRI considerations
Indications
Delayed neurologic deficits after CO exposure
Persistent altered mental status with unclear etiology
Contraindications
MRI incompatible implanted device
Hemodynamic instability
Interpretation pearls
Basal ganglia injury pattern in CO exposure
Alternative diagnoses if atypical pattern
CT
CT considerations
CT chest indications
Suspected inhalation pneumonitis with severe hypoxemia
Concern for occult trauma
CT neck indications
Concern for deep neck space injury
Concern for airway structural injury
Contrast cautions
Kidney injury risk
Contrast allergy history
Interpretation pearls
Airway edema
Ground glass changes for inhalation injury
Ultrasound
POCUS applications
Lung ultrasound
B lines for pulmonary edema
Pneumothorax evaluation
Cardiac ultrasound
LV function assessment
RV strain assessment if alternative diagnosis concern
IVC assessment
Volume status support
Integration with overall shock assessment
Special Tests
Airway evaluation adjuncts
Airway focused tests
Flexible nasolaryngoscopy
Supraglottic edema assessment
Soot and thermal injury assessment
Bronchoscopy
Lower airway soot burden assessment
Airway edema and sloughing assessment
Gas exchange and monitoring adjuncts
Additional physiologic testing
Serial blood gases
Rising PaCO2 for fatigue
Worsening acidosis trend
Serial lactate
Response to resuscitation
Persistent elevation suggesting ongoing toxicity
Continuous end tidal CO2
Ventilation adequacy
Early hypoventilation detection
ECG
Indications and high risk patterns
ECG use cases
Any suspected CO poisoning
Chest pain
Syncope
Palpitations
Older age or cardiac risk factors
High risk ECG findings
ST elevation
ST depression
T wave inversion in ischemic pattern
Ventricular arrhythmia
High grade AV block
Serial ECG logic
Repeat ECG triggers
Persistent symptoms
Rising troponin
Hemodynamic instability
Assessment
Problem representation and severity
Working problem list
Suspected smoke inhalation injury (T27)
Upper airway risk features present
Lower airway symptoms present
Oxygen requirement trend
Suspected carbon monoxide poisoning (T58)
Exposure context supportive
Neurologic symptoms supportive
Carboxyhemoglobin level supportive
Suspected cyanide toxicity (T65.0)
Enclosed space fire supportive
Lactate markedly elevated supportive
Shock supportive
Complications to rule out
Immediate complications
Airway obstruction progression
Acute respiratory failure
Aspiration
ARDS
Myocardial ischemia
Dysrhythmia
Diagnostic uncertainty and alternatives
Alternative diagnoses if discordant data
Asthma exacerbation
COPD exacerbation
Pneumonia
Pulmonary embolism
ACS
Plan
First 5 minutes
Immediate stabilization workflow
Resuscitation bay triggers
Stridor
Altered mental status
SpO2 below 90 percent on oxygen
Hypotension
Monitoring
Continuous pulse oximetry
Continuous cardiac monitoring
End tidal CO2 when available
Access
Two large bore IV if moderate to severe symptoms
IO if unable to obtain IV in unstable patient
Oxygen
Non rebreather 15 L per minute for suspected CO exposure
Escalate to HFNC or NIV for persistent hypoxemia
Airway
Early intubation if high risk airway features
Prepare difficult airway and backup plan
Diagnostics and sequencing
Initial diagnostic bundle
Co oximetry and lactate early
Blood gas early if respiratory distress
ECG within 10 minutes if chest pain or CO concern
Chest radiograph for moderate to severe symptoms
Reassessment loop
Recheck vitals every 15 minutes until stable
Repeat airway exam for evolving edema
Repeat blood gas if rising work of breathing
Repeat lactate if suspected cyanide toxicity
Therapeutics
Respiratory support and symptom control
Bronchodilator for bronchospasm
Salbutamol 5 mg nebulized
Repeat every 20 minutes times 3 then reassess
Ipratropium for moderate to severe bronchospasm
0.5 mg nebulized
Repeat every 20 minutes times 3 then reassess
Systemic steroid for asthma or COPD trigger local protocol dependent
Prednisone 50 mg PO once
Methylprednisolone 125 mg IV once if unable to take PO
Humidified oxygen
Comfort
Secretion clearance
Carbon monoxide poisoning treatment
High flow oxygen until asymptomatic and levels improving
Hyperbaric consult triggers local protocol dependent
Pregnancy
Loss of consciousness
Persistent neurologic symptoms
Myocardial ischemia
Severe metabolic acidosis
Suspected cyanide toxicity treatment
Hydroxocobalamin IV local protocol dependent
Adult dose 5 g IV over 15 minutes
Repeat 5 g IV if severe or persistent instability
Supportive shock care
Balanced crystalloid bolus 500 mL
Repeat based on perfusion and ultrasound findings
Norepinephrine infusion if persistent hypotension
Analgesia and sedation
Avoid respiratory depression when possible
Titrate to effect with close monitoring
Consultation
Specialty involvement
Burn center consult for suspected inhalation injury with burns
Toxicology or poison center consult for CO or cyanide concern
Hyperbaric service consult when criteria met
ICU consult for ventilatory support or significant toxicity
Disposition
ICU and admission criteria
ICU level care criteria
Intubation or impending airway compromise
Persistent hypoxemia requiring HFNC NIV or mechanical ventilation
Hemodynamic instability
Severe acidosis
Significant neurologic impairment
Significant cardiac ischemia or dysrhythmia
Inpatient admission criteria
Oxygen requirement beyond initial ED period
Abnormal chest imaging with symptoms
Persistent bronchospasm after ED therapy
Elevated carboxyhemoglobin with symptoms
Lactate elevation requiring serial monitoring
Observation pathway criteria
Observation appropriate when
Mild to moderate symptoms improving
Stable vitals on minimal oxygen
No high risk airway features
Reliable reassessment capability
Discharge criteria and follow up
Discharge criteria
Normal mentation
No stridor
No hoarseness progression
SpO2 94 percent or higher on room air or baseline requirement
Tolerating oral intake
No concerning ECG changes
Reliable supervision and return access
Follow up timing
Primary care within 48 to 72 hours
Burn clinic follow up if burns present
Pulmonary follow up if persistent symptoms
Discharge Instructions
Copy discharge instructions
Summary
You were evaluated after breathing in smoke
Your breathing and oxygen levels were stable at discharge
Medications
Use your inhaler as prescribed if you have asthma or COPD
If a new inhaler was prescribed take it exactly as directed
Avoid sedating medicines unless prescribed
Activity
Rest for 24 hours
Avoid smoke exposure and strong fumes
Avoid heavy exercise for 24 to 48 hours if symptoms return with exertion
Follow up
See your clinician within 2 to 3 days
Return sooner if symptoms are not improving
Return to the ED immediately for
Trouble breathing at rest
Noisy breathing
New hoarse voice
Trouble swallowing
Chest pain
Fainting
Confusion
Severe headache
Vomiting that prevents drinking fluids
Fever
Worsening cough or coughing blood
References
Guidelines and key sources
Evidence based sources
Advanced Trauma Life Support ATLS 10th edition American College of Surgeons 2018
American Burn Association guidelines for burn care and burn center referral most recent update local protocol dependent
CDC clinical guidance for carbon monoxide poisoning most recent update local protocol dependent
Undersea and Hyperbaric Medical Society UHMS indications for hyperbaric oxygen therapy most recent update local protocol dependent
European Resuscitation Council guidance on toxic exposures and resuscitation relevant sections most recent update local protocol dependent
Goldfrank Toxicologic Emergencies cyanide and carbon monoxide chapters most recent edition
SymptomDx is an educational tool for medical professionals. It does not replace clinical judgment. Verify all clinical data and drug dosages with authoritative sources.