II. Definitions
- Hydrocarbon
- Molecules composed of a core carbon chain (open chain or or cyclic)
- Carbon chain is bound to hydrogen, as well as other elements (e.g. Oxygen, Nitrogen, Sulfur)
- Hydrocarbons are either aromatic or aliphatic
- Halogenated Hydrocarbon
- Hydrocarbons in which a hydrogen is substituted with halogen
- Examples: Chloroform, trichloroethylene
- Aromatic Hydrocarbon
- Cyclic chain (carbon rings, typically hexagonal)
- Examples: Benzene, Toluene, Phenol
- Aliphatic hydrocarbon
- Includes all open chain Hydrocarbons, as well as branched chain Hydrocarbons
- Saturated Aliphatic hydrocarbons contain all single bonds (alkanes)
- Unsaturated Aliphatic hydrocarbons contain double bonds (alkenes) or triple bonds (alkynes)
- Examples include molecules distilled from petroleum
- Gasoline
- Motor oil
- Lighter fluid
- Lamp oil
- Furniture polish
- Paint thinner
III. Epidemiology
- Acute toxic exposures in U.S.: 28,000 per year (50% are pediatric)
- Intentional (e.g. Huffing, Suicide) in 15% of cases
- Occupational Asthma
IV. Pathophysiology
- Types of Hydrocarbons (see definitions above)
- Straight or branched chain Hydrocarbons (aliphatic)
- Ring shaped Hydrocarbons (aromatic)
- Halogenated Hydrocarbons
- Toxicity
- Rapidly absorbed into the cellular lipid bilayer
- Interacts with cellular functionality
- Routes of Injury
- Chemical Burns to skin
- Ingestion (and aspiration risk, esp. in first 30 minutes)
- Inhalation Injury
V. Precautions
- Aspiration into lungs (with Vomiting) is greatest risk
- Common complication of ingestion with Vomiting (esp. in first 30 minutes of ingestion)
- Suspect aspiration if presents with coughing, gagging, Choking, respiratory distress, Hypoxia
- Aspiration is more likely with less viscous, low surface tension, high volatility Hydrocarbons
- Gasoline
- Kerosene
- Naphtha
- High viscosity aspirations (e.g. motor oil) are less likely except in decreased airway protection (low GCS)
- Hydrocarbons are directly toxic to pneumocytes (which produce surfactant)
- Results in pneumocyte destruction, non-compliant lungs and ARDS
VI. Findings: All Hydrocarbons
- Cardiovascular dysfunction
- Hypertension
- Tachyarrythmias (including Ventricular Tachycardia)
- Catecholamine surge
- Myocardial sensitization to Catecholamines and prolonged cardiac depolarization
- Risk of QTc Prolongation (risk of Ventricular Tachycardia, Torsades de Pointes)
- Common with Halogenated Hydrocarbons (e.g. chloroform)
- May occur with other Hydrocarbons
- Pulmonary (aspiration of low viscosity agent destroys surfactant producing cells)
- See Huffing
- Cough
- Dyspnea
- Pneumonitis
- Pulmonary Edema
- Asphyxia
- Neurologic (related to general Anesthetic effects of Hydrocarbons)
- Lethargy to Coma
- Seizures
- Euphoria
- Hallucinations
- Slurred speech
- Disorientation
- Dizziness
- Ataxia
- Gastrointestinal
- Skin
- Risk of Burn Injury, defatting with spills and skin exposure
VII. Findings: Specific Hydrocarbons
- Amyl nitrite
- Chlorinated Hydrocarbons
- Hepatic Dysfunction
- Chlorofluorocarbons
- Cold Injury
- Pulmonary Edema
- Methylene Chloride (Dichloromethane)
- N-Hexane
- Toluene (e.g. Huffing)
VIII. Labs
- See Unknown Ingestion
- Complete Blood Count
- Comprehensive metabolic panel
- Serum Magnesium
- Venous Blood Gas (or Arterial Blood Gas)
- Urinalysis
- Urine Toxicology Screening
IX. Imaging
-
Chest XRay
- Demonstrates aspiration findings within 6 hours in 90% of volatile Hydrocarbon Aspirations
X. Diagnostics
- Electrocardiogram
- Telemetry monitoring
XI. Management
-
Decontamination
- Use soap and water (except in phenol exposure)
- Use topical Polyethylene Glycol for phenol exposure
- Avoid charcoal
- Not effective and risk of further aspiration
- Avoid Nasogastric Tube in most Hydrocarbon Ingestions (NG ineffective)
- Exceptions: Organophosphates, carbon tetrachloride, Benzene, methylene chloride
-
ABC Management with Primary Survey and Secondary Survey
- Monitor full Vital Signs including Oxygen Saturation
- Evaluate for aspiration with secondary respiratory and airway compromise
- Evaluate for hemodynamic instability
- Evaluate for decreased mental status
- Consider Endotracheal Intubation (see Advanced Airway for indications)
- Toxicology
- See Unknown Ingestion for toxicologic evaluation
- Consider life threatening coingestions
- Camphor
- Other Hydrocarbon (aliphatic or Aromatic Hydrocarbon, Halogenated Hydrocarbon)
- Metals
- Pesticides
- Normalize electolyte abnormalities
- Correct Serum Potassium
- Correct Serum Magnesium
- Consider nebulized Bronchodilators (e.g. Albuterol)
- Avoid systemic Terbutaline (may worsen tachydysrhythmia)
- Avoid Corticosteroids (not effective)
- Stabilize Hypotension
- Fluid Resuscitation
- Avoid strong Beta adrenergic Vasopressors (e.g. Epinephrine, Dopamine)
- Decrease Positive End-Expiratory Pressure (PEEP)
- Consider Intravenous Phenylephrine if Vasopressor needed
- Manage Ventricular Arrhythmias
- Follow ACLS Protocol for Ventricular Fibrillation or Ventricular Tachycardia (with the following exceptions)
- Avoid Epinephrine
- Employ Antiarrhythmics (e.g. Amiodarone, Lidocaine) early
- Consider Beta Blocker in refractory ventricular Arrhythmia (decreases myocardial Hypersensitivity)
- Consider Esmolol 500 mcg/kg IV bolus, followed by 50 mcg/kg/min
- Disposition
- Admit all patients with persistent respiratory or neurologic effects
- Observe asymptomatic patients for 6 hours
- Obtain repeat Chest XRay at 6 hours
- If no signs or symptoms of aspiration at 6 hours, typically safe to discharge
- Arrange transfer to higher level of care if signs of aspiration
- ECMO may be considered
- Exogenous surfactant has been used in aspiration cases
XII. Complications
- Chronic neurologic hematologic or oncologic sequelae
XIII. References
- Swadron and Nordt in Herbert (2017) EM:Rap 17(7): 14
- Kinker and Glauser (2021) Crit Dec Emerg Med 35(9): 19-27
- Tomaszewski (2022) Crit Dec Emerg Med 36(5): 32