2. • Hydrocarbons are a heterogenous group of organic
substances that are primarily composed of carbon and
hydrogen molecules. They are quite abundant in modern
society.
• Some of the most commonly ingested hydrocarbons
include gasoline, lubricating oil, motor oil, mineral spirits,
lighter fluid/naphtha, lamp oil, and kerosene.
• Other common sources of hydrocarbons include dry
cleaning solutions, paint, spot remover, rubber cement,
and solvents.
• In addition, many volatile substances that contain
hydrocarbons (eg, glue, propellants) are commonly
abused for their euphoric effects.
3. • Hydrocarbons can be classified as being
aliphatic, in which the carbon moieties are
arranged in a linear or branched chain, or
aromatic, in which the carbon moieties are
arranged in a ring.
• Halogenated hydrocarbons, in which one of the
hydrogen molecules is substituted by a halogen
group. The most important halogenated
hydrocarbons include carbon tetrachloride,
trichloroethylene, tetrachloroethylene,
trichloroethane, chloroform, and methylene
chloride.
4. • Toxicity from hydrocarbon ingestion can
affect many different organs, but the lungs
are the most commonly affected organ.
• The chemical properties of the individual
hydrocarbon determine the specific toxicity,
while the dose and route of ingestion affect
which organs are exposed to the toxicity.
• Unlike the aromatic or aliphatic
hydrocarbons, the halogenated
hydrocarbons tend to cause a wider range
of toxicity.
5. Pathophysiology
• The toxicity of hydrocarbons is directly related
to their physical properties, specifically the
viscosity, volatility, surface tension, and
chemical activity.
• lower viscosity is associated with a higher
chance of aspiration.
• the surface tension is also inversely related to
aspiration risk
• the degree of volatility is directly related with
the risk of aspiration.
6. Pulmonary
• Pulmonary complications, especially aspiration,
are the most frequently reported adverse
effect of hydrocarbon exposure.
• While most aliphatic hydrocarbons have little
GI absorption, aspiration frequently occurs,
either initially or in a delayed fashion as the
patient coughs or vomits, thereby resulting in
pulmonary effects.
• Once aspirated, the hydrocarbons can create a
severe pneumonitis.
7. • Cardiovascular
• Exposure to hydrocarbons can result in cardiotoxicity.
• Most importantly, the myocardium becomes
sensitized to the effects of catecholamines, which
can predispose the patient to tachydysrhythmias,
which can result in syncope or sudden death.
• Gastrointestinal
• Many of the hydrocarbons create a burning
sensation because they are irritating to the GI
mucosa.
• Vomiting has been reported in up to one third of all
hydrocarbon exposures.
8. Hepatic
• The chlorinated hydrocarbons, in particular carbon
tetrachloride, are hepatotoxic.
• Usually, the hepatotoxicity results after the
hydrocarbon undergoes phase I metabolism, thereby
inducing free radical formation.
• These free radicals subsequently bond with hepatic
macromolecules and ultimately cause lipid
peroxidation. This metabolite creates a covalent bond
with the hepatic macromolecules, thereby initiating
lipid peroxidation.
• The common histopathologic pattern is centrilobular
(zone III) necrosis.
9. • Renal chronic exposure to toluene, an
aromatic hydrocarbon, can result in a distal
renal tubular acidosis
• Hematologic
• Prolonged exposure to certain aromatic
hydrocarbons (especially benzene) can lead to
an increased risk of aplastic anemia, multiple
myeloma.
• In addition, hemolysis has been reported
following the acute ingestion of various types
of hydrocarbons.
10. Signs and symptoms
• Pulmonary toxicity most often occurs
following ingestion and subsequent aspiration
of hydrocarbon. Respiratory symptoms (eg,
coughing, gagging, choking) usually occur
within 30 minutes of exposure but often can
be delayed several hours.
• Lack of coughing does not exclude the
possibility of aspiration.
•
11. • The most common CNS symptoms include headache,
lethargy, and decreased mental status.
• in addition, because of sensitization of the myocardium to
catecholamines, a relatively young and previously healthy
patient can present in full cardiac arrest after being
suddenly startled or following strenuous athletic events.
• A common scenario for the cardiac arrest patient is the
teenager who is huffing, or bagging alone in a dark room,
who then gets startled when a parent opens the door.
This "sudden sniffing death syndrome" results in
ventricular fibrillation or ventricular tachycardia, following
a large catecholamine exposure to a myocardium that is
already sensitized to the effects of the catecholamines.
12.
13. Work up
• 1- CBC
• 2- LIVER ENZYMES
• 3- CHEST RADIOGRAPHY
• All symptomatic patients should have a chest x-
ray performed.
• Patients who are asymptomatic (eg, no coughing
or signs/symptoms of respiratory distress) should
not have a chest radiograph obtained
immediately. Rather, asymptomatic patients
should have chest radiography performed at the
end of a 6-hour observation period.
• 4- ECG
14. Managment
1. remove any remaining hydrocarbon that might be on the
clothes or skin
2. Patients should be kept calm to prevent arrhythmia as a
result of myocardial sensitization.
3. All patients should have their airway, breathing, and
circulation managed per routine advanced life support
protocols.
4. Symptomatic patients should receive intravenous access
and cardiac monitoring.
5. The hydrocarbon agent should be transported with the
patient to the hospital, if this can be done in a safe manner.
Bringing the substance to the hospital can permit
identification.
15. • Management for hydrocarbon intoxication
is largely supportive.
• Asymptomatic patients should be observed
with continual pulse-oximetry for a period
of at least 6 hours. If the patient remains
asymptomatic (eg, no coughing, vomiting,
tachypnea, or other evidence of respiratory
difficulties), then a chest radiograph may
be obtained to evaluate for aspiration.
16. • Patients who show signs of impending respiratory failure
despite supplemental oxygen may require rapid sequence
intubation for definitive airway management. Intubation
and positive pressure ventilation may be required for
evidence of on-going respiratory distress.
• If arrhythmias occur, electrolytes, including magnesium
and potassium, should be replaced.
• If ventricular fibrillation occurs, and the thought is that the
arrhythmia is because of myocardial sensitization,
catecholamines, including epinephrine, should be avoided.
In this setting, lidocaine or beta-blockers can be used.
• Decontamination of the GI tract remains controversial.
17. • The use of ipecac-induced emesis is
contraindicated, and activated charcoal does
not absorb hydrocarbons well.
• Antibiotics are frequently given to patients
who develop a pneumonitis following
hydrocarbon aspiration. In animal models,
the empiric administration of antibiotics
altered the lung flora compared with
controls and did not yield any benefit.
Clinically, superinfection can definitely occur
• Steroids have not been proven to be
beneficial.
