2. INTRODUCTION
▪ Hydrocarbons are a diverse group of organic compounds consisting
primarily of carbon and hydrogen atoms.
▪ Products containing hydrocarbons are found in many household and
workplace settings and include fuels, lighter fluids, paint removers,
pesticides, polishers, degreasers, and lubricants.
▪ Some volatile substances may be recreationally abused. Exposure
may cause mild to severe toxicity and, rarely, sudden death.
3. CLINICAL FEATURES
▪ Chemical pneumonitis is the most common pulmonary complication
and is most likely to occur following aspiration of a hydrocarbon with
low viscosity (ability to resist flow), high volatility (tendency for a
liquid to become a gas), and low surface tension (cohesive force
between molecules).
▪ Symptoms occur quickly and include cough, gagging, choking, and
dyspnea. Physical examination may reveal tachypnea, wheezing,
grunting, and an elevated temperature.
▪ Radiographic abnormalities do not always occur. If radiographic
findings occur, they may lag behind the clinical picture by 4 to 24
hours, but most are apparent within 6 hours.
4. CLINICAL FEATURES
▪ Cardiac toxicity manifests as potentially lethal dysrhythmias
resulting from myocardial sensitization to circulating catecholamines
(“sudden sniffing death syndrome”). Halogenated hydrocarbon
solvents are most frequently implicated, but all classes of
hydrocarbons have been associated with dysrhythmias.
▪ Central nervous system toxicity may present as intoxication, ranging
from initial giddiness, agitation, and hallucinations to seizures,
slurred speech, ataxia, and coma. Chronic exposure may cause
recurrent headaches, cerebellar ataxia, and mood lability.
5. CLINICAL FEATURES
▪ Gastrointestinal toxicity can include vomiting (which can lead to
aspiration), abdominal pain, anorexia, and hepatic damage
(particularly from halogenated hydrocarbons such as carbon
tetrachloride, methylene chloride, trichloroethylene, and
tetrachloroethylene).
▪ Dermal toxicity includes contact dermatitis and blistering with
progression to full-thickness burns. Injection of hydrocarbons can
cause tissue necrosis. Burns can result after cutaneous contact with
hot tar and asphalt.
▪ Less common acute toxicities include hematologic disorders such as
hemolysis, methemoglobinemia, carboxyhemoglobinemia (from
methylene chloride), and renal dysfunction.
6. DIAGNOSIS
▪ Determine the specific hydrocarbon-containing product, because
identification can help anticipate specific potential toxicity and guide
management.
▪ Pulse oximetry is useful to evaluate oxygenation status.
▪ Arterial blood gas analysis can be used to assess ventilation and acid-
base status.
▪ Cardiac rhythm monitoring and an ECG are indicated in symptomatic
patients and patients who ingest halogenated hydrocarbons.
7. ▪ Chest radiographs may be normal for as long as 8-12 hr after
aspiration, but more often will be positive after 6 hr or longer from
the time of exposure. whenever possible, chest radiograph should be
delayed until 6 hr or longer after the hydrocarbon exposure.
▪ Chest radiographs may remain abnormal long after the patient is
clinically normal, and they should not be used to guide acute
treatment.
▪ Pneumatoceles may appear on the chest radiograph 2-3 wk after
exposure.
8. DIAGNOSIS
▪ There are no specific quantitative hydrocarbon tests in standard use
when evaluating suspected hydrocarbon intoxication.
▪ A basic metabolic panel is indicated in patients with a history of
toluene abuse or in whom electrolyte abnormalities and renal
insufficiency are suspected.
▪ Obtain hepatic function studies, serum ammonia, and prothrombin
time in patients who ingest or inhale halogenated hydrocarbons.
▪ A CBC is indicated if anemia, bleeding disorder, hemolysis, or
leukemia is considered.
▪ Measure carboxyhemoglobin level in patients with exposure to
methylene chloride; repeat measurements may be necessary.
9. DIAGNOSIS
▪ Determination of methemoglobin level is indicated in patients with
exposure to hydrocarbons containing amine functional groups.
▪ Abdominal radiographs may show evidence of ingestion of
chlorinated hydrocarbons such as carbon tetrachloride or chloroform
because of the radiopaque nature of polyhalogenated substances.22
▪ An outpatient nerve conduction study and electromyography can be
considered in patients who present with chronic numbness and
paresthesias in the extremities and who have a history of n-hexane
exposure.
11. EMERGENCY DEPARTMENT CARE AND DISPOSITION
▪ 1. Secure the airway and maintain ventilation support in patients with
respiratory insufficiency or neurologic depression. Administer oxygen to
symptomatic patients and place them on a cardiac monitor (seeTable 111-
2). An EKG should be obtained.
▪ 2.Treat hypotension with intravenous crystalloid infusion. Avoid
catecholamines except in cases of cardiac arrest.Treat tachydysrhythmias
with propranolol, esmolol, or lidocaine. Avoid class IA and III agents.
▪ 3. Follow standard hazardous material measures for decontamination of
the patient. Initial decontamination should ideally be done at the scene and
should include removal of the patient from the exposure (including clothing
or dermal contact). Skin may be irrigated with soap and water. Activated
charcoal is not indicated following isolated hydrocarbon ingestions.The use
of gastric emptying is not beneficial, and this decontamination technique is
not regularly employed following ingestion.
12. EMERGENCY DEPARTMENT CARE AND DISPOSITION
▪ 4. Meticulous wound care with potential surgical debridement is
indicated for dermal exposures.Treat tar and asphalt injuries with
immediate cooling and cold water, and application of ointment
combined with surface-active agents (e.g., Polysorbate 80).
▪ 5. Prophylactic antibiotics are not generally indicated. Corticosteroid
use is not indicated.
▪ 6. Admit symptomatic patients, those exposed to hydrocarbons
capable of producing delayed toxicity (e.g., halogenated
hydrocarbons), and those exposed to hydrocarbons with toxic
additives (e.g., pesticides or organic metal compounds). Patients
with severe respiratory distress may need
13.
14. DISCHARGE
▪ For pediatric hydrocarbon ingestions, the presence of wheezing,
altered consciousness, or tachypnea within 2 hours predicts the need
for further treatment.
▪ Children with history of exposure are safe to discharge if they have:
1. no symptoms.
2. very transient coughing or gagging.
3. normal physical exam after 4 hours.
4. normal CXR after 6 hours.
