Management of Paraquat Poisoning
In paraquat poisoning, oxygen should be administered only if the saturation falls below 85% and reduced or stopped if the saturation rises above 88%, as supplemental oxygen may worsen paraquat toxicity. 1
Initial Assessment and Management
- Paraquat poisoning is a medical emergency with high mortality rates, requiring immediate intervention 2, 3
- Contact poison control center immediately for expert guidance (1-800-222-1222 in the United States) 1
- Remove all contaminated clothing and jewelry to prevent continued exposure 4
Oxygen Management
- Paraquat poisoning creates a unique situation where oxygen therapy may be harmful 1
- Target oxygen saturation is 85-88%, significantly lower than typical critical care targets 1
- Avoid supplemental oxygen unless the patient is severely hypoxemic (SpO2 <85%) 1
- If oxygen saturation rises above 88%, reduce or stop oxygen therapy 1
Decontamination Measures
- Immediate gastrointestinal decontamination is crucial for survival 3, 5
- Perform gastric lavage as soon as possible after ingestion 5
- Administer activated charcoal orally in large quantities to bind paraquat in the GI tract 5
- Continue activated charcoal administration as much as possible in the early phase 5
Extracorporeal Elimination
- Hemoperfusion with activated charcoal is the most effective method to eliminate paraquat from blood and tissues 5
- Initiate "continuous hemoperfusion" approximately 8 hours/day over a period of 2-3 weeks 5
- Hemodialysis may be used to manage renal failure, which commonly occurs in paraquat poisoning 6
Monitoring and Supportive Care
- Monitor for multi-organ failure, particularly focusing on respiratory, renal, and hepatic function 3
- Assess for development of pulmonary fibrosis, which may not manifest for days or weeks 3
- Standard airway management and treatment of hypotension or dysrhythmias should be provided alongside specific paraquat management 1
Prognosis and Complications
- Prognosis is generally poor with high mortality rates despite aggressive treatment 2
- Severity of poisoning correlates with amount ingested 3:
- Mild poisoning (<20 mg/kg): Generally recoverable with GI symptoms only
- Moderate-severe poisoning (20-40 mg/kg): Renal failure and delayed pulmonary fibrosis
- Acute fulminant poisoning (>40 mg/kg): Multiple organ failure with rapid death