Accidental Petrol (Hydrocarbon) Ingestion

Epidemiology

• Accidental pediatric ingestion is the most common exposure scenario, typically in children under 6 years old
• U.S. poison centers reported >28,500 hydrocarbon exposures in 2018 alone, with ~4,000 pediatric cases/year; ~10% were hospitalised
• Most accidental small-volume ingestions in children have a favourable outcome

Pathophysiology

Why aspiration is the key danger

• Spread rapidly across the oral mucosa and tracheobronchial tree
• Vaporize at body temperature
• Be aspirated easily during swallowing, gagging, or vomiting

Pulmonary injury mechanism

1. Direct toxicity to pulmonary parenchyma
2. Alteration/destruction of surfactant function
3. Destruction of alveolar and capillary membranes → increased vascular permeability → pulmonary oedema
4. Can progress to necrotising pneumonitis and haemorrhagic pulmonary oedema in severe cases

GI absorption

Systemic toxicity

• Aromatic hydrocarbons (benzene, toluene, xylene) — CNS, hepatic, renal, haematologic toxicity
• Halogenated hydrocarbons — ventricular arrhythmias ("sudden sniffing death"), hepatotoxicity
• Petrol containing additives (lead, pesticides) — heavy metal or insecticide toxicity on top

Clinical Features

Key clinical rule: Any patient with coughing, choking, gagging, or dyspnoea after ingestion should be assumed to have aspirated.

Diagnosis

• History is usually straightforward — characteristic petrol odour on breath or clothing
• Chest X-ray at 6 hours after ingestion (bilateral infiltrates; right-sided predominance; multilobar involvement common)
  • Note: CXR findings do not reliably correlate with clinical severity
• Investigations for symptomatic or significant ingestions:
  • Pulse oximetry / ABG
  • Chest X-ray
  • ECG (arrhythmia screening, especially for aromatic/halogenated hydrocarbons)
  • LFTs, renal function if systemic toxicity suspected
  • Screening for co-ingestants in intentional cases

Management

1. Immediate priorities

• Remove contaminated clothing
• Skin: copious irrigation with warm water
• Airway, Breathing, Circulation — assess and support
• Do NOT induce vomiting — this increases aspiration risk
• Do NOT perform gastric lavage or give activated charcoal — not indicated; risks outweigh benefits
• Contact Poison Control Centre / Toxicologist for guidance

2. Respiratory support (if aspiration has occurred)

• Supplemental oxygen for hypoxia
• Inhaled β₂-agonists (e.g., salbutamol) for bronchospasm
• Endotracheal intubation and mechanical ventilation (± PEEP) for severe hypoxia or respiratory failure

3. What NOT to do

4. Monitoring period

• Asymptomatic patients: observe for a minimum of 6 hours
• If still asymptomatic at 6 hours with normal SpO₂ and normal chest exam → can consider discharge with safety-net advice

Discharge Criteria

• Normal GCS
• Normal ECG
• No respiratory symptoms (cough, dyspnoea, wheeze)
• Normal observations including pulse oximetry
• Completed observation period

When to Escalate / Admit

Lethality Reference

• In adults: ~20–50 g can cause severe intoxication; ~350 g may be fatal in a 70 kg adult
• In children: as little as 10–15 g (<0.5 oz) may be fatal — lower threshold for aggressive management in paediatric cases

Clinical bottom line: Do not induce vomiting. The danger is aspiration pneumonitis, not GI absorption. Supportive care, airway monitoring, β-agonists for bronchospasm, and observation for 6 hours are the cornerstones of management. Most small accidental ingestions in children resolve without complication.

Accidental Petrol Ingestion — 26-Year-Old Male

Immediate Priorities on Presentation

1. Call Poison Control immediately (1800 222 1222 USA / National Poisons Information in your region)
2. Do NOT induce vomiting — this is the single most dangerous mistake; it massively increases aspiration risk
3. Remove any petrol-soaked clothing; wash skin with soap and water
4. Assess — is he symptomatic or asymptomatic?

Pathophysiology

• Direct toxicity to pulmonary parenchyma
• Destruction of surfactant
• Breakdown of alveolar-capillary membranes → increased permeability → oedema
• Chemical pneumonitis, potentially progressing to haemorrhagic pulmonary oedema

Risk Stratification for This Patient

Clinical Features to Assess

Early / Immediate

• Burning in mouth and throat
• Coughing, choking, gagging
• Nausea and vomiting
• Petrol odour on breath

Pulmonary (Aspiration)

• Tachypnoea, grunting respirations, wheezing, retractions
• Hypoxia (SpO₂ ↓)
• Fever ≥39°C — may appear 6–8 hours post-exposure (inflammatory pneumonitis)
• Can progress to necrotising pneumonitis, ARDS

Systemic (Large-Volume Ingestion / Aromatic Components)

Any cough, choking, dyspnoea, or gagging = assume aspiration — treat as pulmonary emergency

Emergency Department Management

Step 1 — Decontamination

• Remove contaminated clothing (protect staff from vapour exposure)
• Copious skin washing with soap and water
• Eye irrigation with saline if ocular exposure

Step 2 — Airway and Breathing

• Supplemental oxygen for any hypoxia
• Inhaled β₂-agonists (salbutamol) for bronchospasm/wheeze
• CPAP/BiPAP if oxygenation inadequate on O₂ alone
• Endotracheal intubation + mechanical ventilation (with PEEP) for severe hypoxia, respiratory failure, or CNS depression
• In refractory cases: high-frequency jet ventilation or ECMO (case reports)
• Surfactant therapy — consider for severe pneumonitis

Step 3 — Cardiac Monitoring

• Continuous cardiac monitoring + 12-lead ECG
• Treat ventricular arrhythmias with propranolol, esmolol, or lidocaine
• AVOID catecholamines (adrenaline/epinephrine, dopamine, noradrenaline) — these sensitise the myocardium and can precipitate fatal arrhythmias
• Avoid class IA (procainamide) and class III (amiodarone, sotalol) antiarrhythmics — risk of QT prolongation

Step 4 — IV Access & Fluids

• IV access in symptomatic patients
• IV crystalloid for hypotension

Step 5 — What NOT to Do

Investigations

CXR findings do not reliably predict clinical severity — manage based on symptoms.

Chest radiograph at 6 hours after hydrocarbon ingestion — note bilateral airspace infiltrates consistent with aspiration pneumonitis. — Rosen's Emergency Medicine, p. 2995

Observation Period & Disposition

Discharge Criteria (all must be met)

• Normal GCS and orientation
• Normal ECG
• No respiratory symptoms (no cough, dyspnoea, wheeze)
• Normal SpO₂ on room air
• Normal observations throughout 6-hour period
• Asymptomatic without CXR findings

Prognosis

• Most accidental small-volume petrol ingestions in adults — if no aspiration occurs — have a favourable outcome
• Aspiration pneumonitis is the main cause of morbidity and mortality
• If symptomatic, most patients improve within 2–5 days with supportive care
• Severe cases can progress to ARDS with significant mortality
• A 26-year-old otherwise healthy male has favourable reserve, but prompt assessment is essential

Bottom line for this patient: Transport to ED. Do not induce vomiting. Monitor for 6 hours minimum. Respiratory symptoms = aspiration until proven otherwise — treat aggressively with O₂ and bronchodilators. Avoid all catecholamines if arrhythmia develops.