Petroleum compounds (hydrocarbons) poisoning occurs after ingestion, inhalation, or dermal exposure to volatile petroleum distillates. These substances are commonly found in households and garages and are a frequent cause of childhood accidental poisoning.

Common Agents

• Kerosene (paraffin)

• Petrol (gasoline)

• Diesel

• Turpentine and paint thinners

• Mineral spirits

• Lighter fluid

• Lubricating oils

The major danger is aspiration into the lungs, causing chemical pneumonitis, rather than systemic absorption.

2. Mechanism of Toxicity (Pathophysiology)

Hydrocarbons have:

• Low viscosity

• High volatility

• Low surface tension

These properties allow rapid spread in the lungs after aspiration → alveolar destruction

Main injury mechanisms

1. Surfactant dissolution → alveolar collapse

2. Direct epithelial injury → inflammation

3. Chemical pneumonitis

4. Hypoxia

5. Secondary bacterial infection

Some aromatic hydrocarbons (e.g., benzene-containing petrol) also cause:

• CNS depression

• Cardiac sensitization → arrhythmias

3. Risk Factors

• Toddlers (1–5 years) accidental ingestion

• Storage in beverage bottles

• Poor supervision

• Occupational exposure (mechanics, fuel attendants)

• Intentional ingestion (self-harm)

• Fire eaters (performers)

• Indoor fuel siphoning

4. Clinical Features

Symptoms usually appear within minutes to 6 hours after exposure.

A. Gastrointestinal

• Abdominal pain

• Bloody stool

• Vomiting

• Nausea

Vomiting increases aspiration risk

B. Respiratory (Most Important)

• Throat irritation/swelling

• Cough

• Tachypnea

• Cyanosis

• Crepitations

• Rhonchi

• Pneumonitis

• Pulmonary edema

• Respiratory failure

C. Central Nervous System

• Headache

• Dizziness

• Euphoria

• Restlessness

• Ataxia

• Convulsions

• Encephalopathy

• Coma

D. Cardiovascular

• Tachycardia

• Ventricular arrhythmias (especially petrol)

• Hypotension (severe cases)

5. Diagnostic Criteria

Diagnosis is mainly clinical + exposure history

Suggestive clues:

• Smell of fuel on breath/clothes

• Sudden coughing after ingestion

• Respiratory distress after vomiting

• Abnormal lung auscultation

6. Investigations

Essential

• Pulse oximetry

• Chest X-ray (after 4–6 hours)

• Arterial blood gases

• Serum electrolytes

Additional

• ECG monitoring (arrhythmias)

• FBC (secondary infection)

• CRP (if worsening)

• CT chest (severe pneumonitis)

Initial chest X-ray may be normal

7. Management

Golden Rule: Prevent aspiration

8. Non-Pharmacological Treatment

Immediate Care

• Remove from exposure

• Remove contaminated clothing

• Wash skin thoroughly with soap and water

• Irrigate eyes if exposed

Airway & Breathing

• Give oxygen if hypoxic

• Continuous monitoring

• Early intubation if respiratory distress

Gastrointestinal Care

DO NOT induce vomiting⚠ DO NOT give activated charcoal (ineffective & aspiration risk)

If large ingestion <1 hour:

• Consider gastric lavage ONLY AFTER INTUBATION

Positioning

• Left lateral head-down position (reduces aspiration)

9. Pharmacological Treatment

Supportive Therapy (Mainstay)

No specific antidote exists.

Bronchospasm

• Nebulized salbutamol

Severe Pneumonitis

• Mechanical ventilation

• PEEP support

Antibiotics

NOT routineOnly if:

• Fever after 48 hours

• Worsening infiltrates

• Elevated inflammatory markers

Suggested:

• Amoxicillin-clavulanateor

• Ceftriaxone

Corticosteroids

Not routinely recommendedMay be used in severe chemical pneumonitis (controversial)

Arrhythmias

Avoid catecholamines when possibleTreat per ACLS protocols

10. Monitoring

Observe at least 24 hours if symptomatic

Monitor:

• Respiratory rate

• Oxygen saturation

• Lung exam

• Neurological status

Repeat chest X-ray if worsening

11. Complications

• Chemical pneumonitis

• ARDS

• Secondary bacterial pneumonia

• Lung abscess

• Chronic lung disease

• Hypoxic brain injury

• Death

12. Prognosis

Good in mild exposurePoor if:

• Severe hypoxia

• ARDS

• CNS depression

Most deaths occur due to respiratory failure

13. Prevention

Do’s

• Store fuels locked away

• Keep in original containers

• Child-resistant caps

• Educate caregivers

Don’ts

• Never store in soda/water bottles

• Never siphon fuel by mouth

• Never induce vomiting after ingestion

• Never leave containers open