Management of Seizures in Organophosphate (OP) Poisoning
Benzodiazepines are the first-line treatment for seizures in organophosphate poisoning, with airway management and ventilatory support as critical concurrent interventions. 1
Initial Assessment and Management
- Secure airway, breathing, and circulation following standard resuscitation protocols as the first priority 1
- For patients in respiratory arrest, provide rescue breathing or bag-mask ventilation until spontaneous breathing returns 1
- If cardiac arrest is suspected, focus on high-quality CPR (compressions plus ventilation) as the primary intervention 1
- Activate emergency response systems immediately without delay 1
Seizure Management in OP Poisoning
- Benzodiazepines are the first-line anticonvulsant therapy for OP-induced seizures 1, 2
- Lorazepam IV is a preferred benzodiazepine option for status epilepticus, with a recommended dose of 4 mg given slowly (2 mg/min) for adults 3
- If seizures continue after 10-15 minutes, an additional 4 mg IV dose of lorazepam may be administered 3
- Maintain an unobstructed airway and have artificial ventilation equipment available, as respiratory depression is the most important risk associated with benzodiazepine use 3
Supportive Care
- Monitor vital signs closely, as stable vitals can deteriorate in poisoning situations 4
- Consider escalating to bag-mask ventilation if respiratory effort becomes inadequate 4
- Be prepared for endotracheal intubation if respiratory status continues to deteriorate despite supportive measures 4
Special Considerations for OP Poisoning
- The cornerstones of OP poisoning treatment include decontamination, atropine, benzodiazepines, and oximes 1
- Dermal decontamination through removal of contaminated clothing and copious irrigation with soap and water helps prevent further absorption 1
- Atropine blocks parasympathetic overstimulation, mitigating bronchorrhea, bradycardia, bronchospasm, and CNS effects 1
- Atropine does not block acetylcholine excess at the neuromuscular junction, so benzodiazepines are essential for controlling seizures 1
Role of Naloxone
- Naloxone has no role in the management of organophosphate-induced seizures 5
- If opioid co-ingestion is suspected, naloxone may be administered along with standard care if it does not delay components of high-quality care 1
- For suspected opioid overdose with a definite pulse but no normal breathing, it is reasonable to administer naloxone in addition to standard care 1
Monitoring and Disposition
- Observe patients closely for recurrent seizures and respiratory depression 3
- Be alert to the possibility of prolonged sedation from benzodiazepines, especially when multiple doses have been given 3
- Equipment necessary to maintain a patent airway and support respiration/ventilation should be available throughout treatment 3
Common Pitfalls to Avoid
- Failing to consider co-ingestions, which may require specific antidotes 6
- Focusing solely on one aspect of poisoning when polysubstance exposure may be present 4
- Delaying definitive airway management when initial interventions are ineffective 4
- Using phenytoin, which has no role in the treatment of drug-induced seizures 2