II. Definitions

  1. Hydrocarbon
    1. Molecules composed of a core carbon chain (open chain or or cyclic)
    2. Carbon chain is bound to hydrogen, as well as other elements (e.g. Oxygen, Nitrogen, Sulfur)
    3. Hydrocarbons are either aromatic or aliphatic
  2. Halogenated Hydrocarbon
    1. Hydrocarbons in which a hydrogen is substituted with halogen
    2. Examples: Chloroform, trichloroethylene
  3. Aromatic Hydrocarbon
    1. Cyclic chain (carbon rings, typically hexagonal)
    2. Examples: Benzene, Toluene, Phenol
  4. Aliphatic hydrocarbon
    1. Includes all open chain Hydrocarbons, as well as branched chain Hydrocarbons
    2. Saturated Aliphatic hydrocarbons contain all single bonds (alkanes)
    3. Unsaturated Aliphatic hydrocarbons contain double bonds (alkenes) or triple bonds (alkynes)
    4. Examples include molecules distilled from petroleum
      1. Gasoline
      2. Motor oil
      3. Lighter fluid
      4. Lamp oil
      5. Furniture polish
      6. Paint thinner

III. Epidemiology

  1. Acute toxic exposures in U.S.: 28,000 per year (50% are pediatric)
    1. Intentional (e.g. Huffing, Suicide) in 15% of cases
    2. Occupational Asthma

IV. Pathophysiology

  1. Types of Hydrocarbons (see definitions above)
    1. Straight or branched chain Hydrocarbons (aliphatic)
    2. Ring shaped Hydrocarbons (aromatic)
    3. Halogenated Hydrocarbons
  2. Toxicity
    1. Rapidly absorbed into the cellular lipid bilayer
    2. Interacts with cellular functionality
  3. Routes of Injury
    1. Chemical Burns to skin
    2. Ingestion (and aspiration risk, esp. in first 30 minutes)
    3. Inhalation Injury

V. Precautions

  1. Aspiration into lungs (with Vomiting) is greatest risk
    1. Common complication of ingestion with Vomiting (esp. in first 30 minutes of ingestion)
    2. Suspect aspiration if presents with coughing, gagging, Choking, respiratory distress, Hypoxia
    3. Aspiration is more likely with less viscous, low surface tension, high volatility Hydrocarbons
      1. Gasoline
      2. Kerosene
      3. Naphtha
    4. High viscosity aspirations (e.g. motor oil) are less likely except in decreased airway protection (low GCS)
  2. Hydrocarbons are directly toxic to pneumocytes (which produce surfactant)
    1. Results in pneumocyte destruction, non-compliant lungs and ARDS

VI. Findings: All Hydrocarbons

  1. Cardiovascular dysfunction
    1. Hypertension
    2. Tachyarrythmias (including Ventricular Tachycardia)
    3. Catecholamine surge
      1. Fever
      2. Hypertension
      3. Tachycardia
    4. Myocardial sensitization to Catecholamines and prolonged cardiac depolarization
      1. Risk of QTc Prolongation (risk of Ventricular Tachycardia, Torsades de Pointes)
      2. Common with Halogenated Hydrocarbons (e.g. chloroform)
      3. May occur with other Hydrocarbons
  2. Pulmonary (aspiration of low viscosity agent destroys surfactant producing cells)
    1. See Huffing
    2. Cough
    3. Dyspnea
    4. Pneumonitis
    5. Pulmonary Edema
    6. Asphyxia
  3. Neurologic (related to general Anesthetic effects of Hydrocarbons)
    1. Lethargy to Coma
    2. Seizures
    3. Euphoria
    4. Hallucinations
    5. Slurred speech
    6. Disorientation
    7. Dizziness
    8. Ataxia
  4. Gastrointestinal
    1. Nausea
    2. Vomiting
    3. Abdominal Pain
    4. Diarrhea
  5. Skin
    1. Risk of Burn Injury, defatting with spills and skin exposure

VII. Findings: Specific Hydrocarbons

  1. Amyl nitrite
    1. Methemoglobinemia
  2. Chlorinated Hydrocarbons
    1. Hepatic Dysfunction
  3. Chlorofluorocarbons
    1. Cold Injury
    2. Pulmonary Edema
  4. Methylene Chloride (Dichloromethane)
    1. Carbon Monoxide Poisoning
  5. N-Hexane
    1. Neuropathy
  6. Toluene (e.g. Huffing)
    1. Hypokalemia
    2. Acute Kidney Injury
    3. Hepatotoxicity
    4. High Anion Gap Metabolic Acidosis
    5. Altered Mental Status
    6. Ataxia

IX. Imaging

  1. Chest XRay
    1. Demonstrates aspiration findings within 6 hours in 90% of volatile Hydrocarbon Aspirations

X. Diagnostics

  1. Electrocardiogram
  2. Telemetry monitoring

XI. Management

  1. Decontamination
    1. Use soap and water (except in phenol exposure)
    2. Use topical Polyethylene glycol for phenol exposure
    3. Avoid charcoal
      1. Not effective and risk of further aspiration
    4. Avoid Nasogastric Tube in most Hydrocarbon Ingestions (NG ineffective)
      1. Exceptions: Organophosphates, carbon tetrachloride, Benzene, methylene chloride
  2. ABC Management with Primary Survey and Secondary Survey
    1. Monitor full Vital Signs including Oxygen Saturation
    2. Evaluate for aspiration with secondary respiratory and airway compromise
    3. Evaluate for hemodynamic instability
    4. Evaluate for decreased mental status
    5. Consider Endotracheal Intubation (see Advanced Airway for indications)
  3. Toxicology
    1. See Unknown Ingestion for toxicologic evaluation
    2. Consider life threatening coingestions
      1. Camphor
      2. Other Hydrocarbon (aliphatic or Aromatic Hydrocarbon, Halogenated Hydrocarbon)
      3. Metals
      4. Pesticides
  4. Normalize electolyte abnormalities
    1. Correct Serum Potassium
    2. Correct Serum Magnesium
  5. Consider nebulized Bronchodilators (e.g. Albuterol)
    1. Avoid systemic Terbutaline (may worsen tachydysrhythmia)
    2. Avoid Corticosteroids (not effective)
  6. Stabilize Hypotension
    1. Fluid Resuscitation
    2. Avoid strong Beta adrenergic Vasopressors (e.g. Epinephrine, Dopamine)
    3. Decrease Positive End-Expiratory Pressure (PEEP)
    4. Consider Intravenous Phenylephrine if Vasopressor needed
  7. Manage Ventricular Arrhythmias
    1. Follow ACLS Protocol for Ventricular Fibrillation or Ventricular Tachycardia (with the following exceptions)
    2. Avoid Epinephrine
    3. Employ Antiarrhythmics (e.g. Amiodarone, Lidocaine) early
    4. Consider Beta Blocker in refractory ventricular Arrhythmia (decreases myocardial Hypersensitivity)
      1. Consider Esmolol 500 mcg/kg IV bolus, followed by 50 mcg/kg/min
  8. Disposition
    1. Admit all patients with persistent respiratory or neurologic effects
    2. Observe asymptomatic patients for 6 hours
      1. Obtain repeat Chest XRay at 6 hours
      2. If no signs or symptoms of aspiration at 6 hours, typically safe to discharge
    3. Arrange transfer to higher level of care if signs of aspiration
      1. ECMO may be considered
      2. Exogenous surfactant has been used in aspiration cases

XII. Complications

  1. Chronic neurologic hematologic or oncologic sequelae

XIII. References

  1. Swadron and Nordt in Herbert (2017) EM:Rap 17(7): 14
  2. Kinker and Glauser (2021) Crit Dec Emerg Med 35(9): 19-27
  3. Tomaszewski (2022) Crit Dec Emerg Med 36(5): 32

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