Hydrocarbon Aspiration

Hydrocarbon Aspiration

Juan C. Martinez, MD, FAAP

Introduction/Etiology/Epidemiology

•The main pediatric exposures to hydrocarbons include accidental ingestion and intentional inhalational abuse by adolescents.

•Most accidental ingestions occur in children <5 years of age. The highest-risk exposures occur in boys 1–2 years of age.

Pathophysiology

•Toxicity is related to the amount of hydrocarbons ingested, as well as volatility, surface tension, viscosity, and lipid solubility. Vomiting increases the risk of pulmonary involvement.

•Rapid and severe pulmonary edema is likely related to loss of surfactant and direct tissue destruction.

•Hydrocarbons with low viscosity and surface tension and high volatility (eg, gasoline, kerosene, lighter fluid) are associated with increased respiratory symptoms and greater risk of aspiration (Figure 81-1).

•Hydrocarbons disrupt surfactant and dampen pulmonary compliance.

•They can cause direct pulmonary injury, with direct inflammatory response and pulmonary edema, necrosis, and chemical pneumonitis.

•Bronchospasm, edema, and ventilation perfusion mismatch may all contribute to hypoxemia.

•Inhaled hydrocarbons are absorbed through the lungs and act as central nervous system (CNS) depressants. Inhibition of N-methyl-D-aspartate receptors with acute exposure is believed to contribute to CNS depression.

•Pneumatoceles can occur and usually resolve over weeks to months.

Clinical Features

•Respiratory symptoms usually develop quickly after the aspiration event, but there may be a delay in presentation (Table 81-1). Forty-six percent to 65% of patients are asymptomatic at presentation.

•The most common signs and symptoms include fever, vomiting, cough, and tachypnea.

•Symptoms typically worsen during the initial 24–48 hours and resolve over 10–14 days.

•Fever, tachypnea, and tachycardia suggest pneumonia.