Immediate Management of Organophosphate Poisoning
The immediate management of organophosphate poisoning requires prompt administration of atropine, early airway management, benzodiazepines for seizures, appropriate personal protective equipment, and dermal decontamination. 1
Initial Assessment and Protection
- Personal protection first: Use appropriate personal protective equipment when caring for patients with organophosphate exposure to prevent secondary contamination 1
- Decontamination: Immediately remove contaminated clothing and perform thorough irrigation with soap and water for external exposure 1
Primary Interventions (In Order of Priority)
1. Atropine Administration
- Administer atropine immediately for severe poisoning manifestations such as:
- Bronchospasm
- Bronchorrhea (excessive secretions)
- Bradycardia
- Seizures 1
- Dosing:
- Adults: 2-4 mg IV initially
- Double dose every 5 minutes until atropinization is achieved (clear lungs, HR >80/min, SBP >80 mmHg)
- Maintain atropinization for at least 48 hours 2
2. Airway Management
- Early endotracheal intubation for life-threatening organophosphate poisoning 1
- Ensure adequate oxygenation before administering atropine to prevent atropine-induced ventricular fibrillation 2
3. Seizure Control
- Administer benzodiazepines (diazepam preferred) to treat seizures and agitation 1
- Benzodiazepines help prevent and treat CNS effects of organophosphate poisoning 3
4. Oxime Therapy
- Administer pralidoxime (2-PAM) for organophosphate poisoning 1
- Dosing:
- Initial dose: 1000-2000 mg IV, preferably as infusion in 100 mL normal saline over 15-30 minutes
- If infusion not practical: administer slowly over at least 5 minutes as 50 mg/mL solution
- Second dose: 1000-2000 mg after one hour if muscle weakness persists
- Additional doses every 10-12 hours as needed 2
Supportive Care
- Fluid resuscitation to maintain adequate perfusion
- Monitor vital signs continuously
- Correct metabolic abnormalities as they arise
- Continue observation for at least 48-72 hours after exposure 2
Important Cautions
- Avoid certain medications that may worsen condition:
- Morphine
- Theophylline/aminophylline
- Reserpine
- Phenothiazine-type tranquilizers 2
- Do not use succinylcholine or mivacurium for intubation as these are metabolized by cholinesterase and may cause prolonged paralysis 1
Clinical Pearls
- Organophosphate poisoning presents with both muscarinic effects (DUMBELS: Diarrhea, Urination, Miosis, Bronchospasm/Bronchorrhea, Emesis, Lacrimation, Salivation) and nicotinic effects (fasciculations, paralysis) 3
- Secondary contamination of healthcare providers can occur through direct contact with the patient or their secretions, as documented in cases of mouth-to-mouth resuscitation 4
- Treatment should continue until clinical improvement is observed, as relapses can occur due to continued absorption from the GI tract 2
- Early recognition and aggressive treatment are essential to minimize morbidity and mortality 5