Toxicology - Hydrocarbon Flashcards
refers to the general “thickness” of a liquid
Viscosity
lower viscosity flow more easily than ones with high viscosity
measured in Saybolt universal seconds (SUS)
low viscosity
gasoline, kerosene, mineral seal oil, and turpentine
high viscosity (>100 SUS)
diesel fuel, grease, mineral oil, paraffin wax, and petroleum jelly
refers to the property where liquid molecules tend to cohere to each other
Surface tension
refers to the ability of the liquid or solid to vaporize and is inversely related to the boiling point
Volatility
highly volatile liquids have a low boiling point.
Ingestion of liquids with low viscosity and surface tension and high volatility increases the risk for aspiration because these substances flow easily, spreading out widely on the oral mucosa, and vaporize at body temperature.
Pulmonary effects
Tachypnea, grunting respirations, wheezing, retractions
Necrotizing pneumonitis and hemorrhagic pulmonary edema may develop within minutes to hours
With less severe d age, symptoms usually subside within 2 to 5 days, except in the case of pneumatoceles and lipoid pneumonias
Cardiac effects
Ventricular dysrhythmias (may occur after exposure to halogenated hydrocarbons and aromatic hydrocarbons)
Central nervous
Slurred speech, ataxia, lethargy, coma
(1) direct toxic response to the systemic absorption of the hydrocarbon,
(2) indirect result of severe hypoxia secondary to aspiration, (3) simple asphyxiation due to the displacement of oxygen by the volatile hydrocarbon, or
(4) volatile substance abuse with a plastic bag that prevents adequate oxygenation
Peripheral nervous
Numbness and paresthesias in the extremities
GI AND HEPATIC EFFECTS
Nausea, vomiting, abdominal pain, hepatotoxicity, loss of appetite (mostly with halogenated hydrocarbons)
Renal and metabolic
Muscle weakness or paralysis secondary to hypokalemia in patients who abuse toluene
metabolic profile of renal tubular acidosis is a normal anion gap hyperchloremic acidosis with hypokalemia and a urine pH of >5.5.
Hematologic effects
Lethargy (anemia), shortness of breath (anemia), neurologic depression/syncope (carbon monoxide from methylene chloride), cyanosis (methemoglobinemia from aminecontaining hydrocarbons)
aplastic anemia, acute myelogenous leukemia, and multiple myeloma
Naphthalene exposure is associated with hemolytic anemia
Dermal
Local erythema, papules, vesicles, generalized scarlatiniform eruption, exfoliative dermatitis, “huffer’s rash,” cellulitis
most common radiologic finding
bilateral infiltrates at the bases.
Multilobar involvement is more c mon than single-lobe involvement, and right-sided involvement is more common than left-sided involvement
Changes may be seen on radiology
early as 30 minutes after aspiration, but the initial radiograph in a symptomatic patient may be deceptively clear. Conversely, an asymptomatic patient can still have abnormal chest radiographic findings.
usually appear by 2 to 6 hours;
almost always present by 24 hours