Hydrocarbons Toxicity Clinical Presentation

Updated: Dec 17, 2019
  • Author: Mityanand Ramnarine, MD, FACEP; Chief Editor: Stephen L Thornton, MD  more...
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Typical features of unintentional hydrocarbon ingestion include the following:

  • The most common scenario involves a young child whose ingestion is often not witnessed; the parent may smell the chemical on the child's skin, clothing, or breath, or they may report that their child is coughing, choking, cyanotic, or vomiting

  • If the ingestion is unwitnessed, the amount ingested is usually impossible to quantify

  • Sources of ingested hydrocarbons range from cleaning products in the kitchen to solvents in the garage; often, these chemicals are not properly labeled, or they are inadvertently stored in a beverage container

  • A history of coughing, choking, vomiting, or cyanosis is highly correlated with the likelihood of pulmonary aspiration

Intentional inhalation of volatile hydrocarbons uses the following techniques:

  • Sniffing involves inhaling the fumes of a liquid from an open container

  • Huffing involves applying the chemical to a cloth or rag and then inhaling the hydrocarbon by covering the nose and mouth with the cloth or rag

  • Bagging involves placing the hydrocarbon in a bag and then placing the bag over the face to inhale the fumes


Physical Examination

In cases of hydrocarbon aspiration, the patient's temperature may be elevated due to the body's reaction to the foreign substance. Respiratory, central nervous system (CNS), and gastrointestinal (GI) findings may be present, as well as cardiac arrhythmias, mucosal irritation, and chemical burns of the skin.

Respiratory findings may include the following:

  • Coughing
  • Choking
  • Tachypnea
  • Grunting
  • Cyanosis
  • Rales
  • Wheezing

CNS findings may include the following:

  • Dizziness
  • Lethargy
  • Ataxia
  • Seizures
  • Coma

GI findings may include the following:

  • Nausea
  • Vomiting
  • Abdominal pain

Acute Inhalation

CNS intoxication occurs in three stages. [10]  Stage 1 includes mild effects that users may find enjoyable, and thus lead to chronic abuse.These effects include euphoria, excitability, disinhibition, and impulsive behavior. However, stage 1 also commonly features headache, dizziness, and nausea, followed by dysesthesia of tongue, numbness of legs, muscular weakness, tinnitus, blurry vision/diplopia, tremors, and ataxia. Some users may also exhibit aggressive behavior, irritability, amnesia, and slurred speech.

Stage 2 involves CNS depression. Slurred speech, confusion, and hallucination are the most common findings in this stage. In stage 3, the CNS depression seen in stage 2 further progresses to obtundation, coma, seizures, and possibly death.

Sudden cardiac death may occur after an acute heavy exposure to high concentrations of hydrocarbons, followed by physical exertion or extreme excitation due to the myocardial sensitization to the surge in epinephrine circulating during such instances. Coronary vasospasm may also occur, leading to acute myocardial infarction.

Chronic Inhalation

The most common sequelae of long-term use include muscle weakness, tremor, and peripheral neuropathy. No definite timeframe of use has been determined for onset of signs of chronic inhalation, with no clear cumulative dose-response relationship. However, most of the signs do not develop until the persons has been inhaling hydrocarbons two to three times weekly for about 6 months. [10]

Chronic use leads to memory impairment and may place users at higher risk of psychiatric disorders. In one study of adult inhalant users, the prevalence of such disorders was as follows [10] :

  • Mood disorders – 48%
  • Anxiety disorders – 36%
  • Personality disorders – 45%

Disorders that result from long-term hydrocarbon inhalation may be reversible with discontinuation of use. Resolution of the disorder may be incomplete, however.