Grading Hydrocarbon Pneumonitis

 

Examples of commonly aspirated hydrocarbons: petroleum solvents, lighter fluid, dry cleaning fluids, spot removers, gasoline. Other chemicals dissolved in the hydrocarbon (as in cleaning fluids) may be more toxic than the hydrocarbons.

 

The viscosity of the hydrocarbon correlates with its aspiration potential.

(1) hydrocarbons with low viscosity (35 Saybold Universal Seconds, or SUS) like gasoline have a very high aspiration potential)

(2) hydrocarbons with viscosity of 60 SUS show moderate aspiration potential

(3) hydrocarbons with viscosity of 80 SUS show low aspiration potential

(4) hydrocarbons with high viscosity may produce a lipoid pneumonia rather than a pneumonitis

 

Situations of exposure include accident ingestion by small children, aspiration while siphoning, or suicide intent. Chemical pneumonitis is uncommon in persons abusing hydrocarbons as a volatile intoxicant.

 

Moderate fever (38 to 39°C) can be shortly (30-60 minutes) after ingestion but tends to resolve in 24 hours. The presence of high fever several days after exposure may indicate a secondary infection such as aspiration pneumonia.

Airways and Lungs	CNS (affected by type of hydrocarbon)	Severity
coughing, choking, tachypnea, rales, rhonchi	irritability, drowsiness	mild
grunting, bronchospasm, continuing nonproductive cough	lethargy, flaccid	moderate
grunting respirations, cyanosis, hemoptysis	coma, seizures	severe

 

Changes on chest X-ray do not correlate with the severity of clinical symptoms:

(1) fine punctuate, mottled densities in perihilar area

(2) basal pneumonitis and/or atelectasis

(3) areas of consolidation

(4) peripheral obstructive emphysema

(5) pleural effusions

(6) pneumatoceles and cysts

 

In severe cases death may occur within the first 24 hours. In children who survive the illness usually lasts 3-5 days. In adults it may persist for weeks.

 

Vomiting should not be induced since this can result in aspiration and may worsen the choking and coughing.