Template:Cholinergic Toxicity Treatment: Difference between revisions

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==Antidotes==
==Antidotes==
===[[Atropine]]===
===[[Atropine]]===
*'''First-line antidote''' — muscarinic antagonist; treats bronchorrhea, bronchospasm, bradycardia, and secretions<ref name="medscape">Eddleston M, Buckley NA, Eyer P, Dawson AH. Management of acute organophosphorus pesticide poisoning. Lancet. 2008;371(9612):597-607. doi:10.1016/S0140-6736(07)61202-1</ref>
*'''First-line antidote''' — muscarinic antagonist; treats bronchorrhea, bronchospasm, bradycardia, and secretions<ref>Eddleston M, Buckley NA, Eyer P, Dawson AH. Management of acute organophosphorus pesticide poisoning. Lancet. 2008;371(9612):597-607. doi:10.1016/S0140-6736(07)61202-1</ref>
*'''Does NOT reverse nicotinic symptoms''' (weakness, fasciculations, paralysis)
*'''Does NOT reverse nicotinic symptoms''' (weakness, fasciculations, paralysis)
*Starting dose: {{MedicationDose|drug=Atropine|dose=1-2 mg IV (double q5min until atropinization)|route=IV|context=Cholinergic toxicity antidote (muscarinic)|indication={{PAGENAME}}|population=Adult|notes=May need 100+ mg in first 24h; endpoint is drying of secretions}}
*Starting dose: {{MedicationDose|drug=Atropine|dose=1-2 mg IV (double q5min until atropinization)|route=IV|context=Cholinergic toxicity antidote (muscarinic)|indication={{PAGENAME}}|population=Adult|notes=May need 100+ mg in first 24h; endpoint is drying of secretions}}
*Pediatric: {{MedicationDose|drug=Atropine|dose=0.02-0.05 mg/kg IV (min 0.1 mg), double q5min|route=IV|context=Cholinergic toxicity antidote (muscarinic)|indication={{PAGENAME}}|population=Pediatric}}
*Pediatric: {{MedicationDose|drug=Atropine|dose=0.02-0.05 mg/kg IV (min 0.1 mg), double q5min|route=IV|context=Cholinergic toxicity antidote (muscarinic)|indication={{PAGENAME}}|population=Pediatric}}
*'''Doubling protocol''': If inadequate response after 5 minutes, double the dose (1 → 2 → 4 → 8 → 16 mg...) until atropinization is achieved<ref name="medscape"/>
*'''Doubling protocol''': If inadequate response after 5 minutes, double the dose (1 → 2 → 4 → 8 → 16 mg...) until atropinization is achieved<ref>Eddleston M, Buckley NA, Eyer P, Dawson AH. Management of acute organophosphorus pesticide poisoning. Lancet. 2008;371(9612):597-607. doi:10.1016/S0140-6736(07)61202-1</ref>
*Massive doses may be required — total doses of 100+ mg in the first 24 hours have been reported<ref name="bmj">Eddleston M, Chowdhury FR. Pharmacological treatment of organophosphorus insecticide poisoning: the old and the (possible) new. Br J Clin Pharmacol. 2016;81(3):462-470. doi:10.1111/bcp.12784</ref>
*Massive doses may be required — total doses of 100+ mg in the first 24 hours have been reported<ref>Eddleston M, Chowdhury FR. Pharmacological treatment of organophosphorus insecticide poisoning: the old and the (possible) new. Br J Clin Pharmacol. 2016;81(3):462-470. doi:10.1111/bcp.12784</ref>
*'''Endpoints of adequate atropinization''' (goal of therapy):
*'''Endpoints of adequate atropinization''' (goal of therapy):
**Drying of bronchial secretions ('''most important endpoint''')
**Drying of bronchial secretions ('''most important endpoint''')
**Heart rate >80 bpm
**Heart rate >80 bpm
**Systolic BP >80 mmHg
**Systolic BP >80 mmHg
*'''Do NOT target''': Fully dilated pupils, absent bowel sounds, or HR >150 — these indicate atropine toxicity<ref name="wfsa">Mitra RL, Mohan S. Anaesthesia and organophosphorus poisoning. World Federation of Societies of Anaesthesiologists. Anaesthesia Tutorial of the Week. 2011.</ref>
*'''Do NOT target''': Fully dilated pupils, absent bowel sounds, or HR >150 — these indicate atropine toxicity<ref>Mitra RL, Mohan S. Anaesthesia and organophosphorus poisoning. World Federation of Societies of Anaesthesiologists. Anaesthesia Tutorial of the Week. 2011.</ref>
*After initial atropinization: Consider atropine infusion (10-20% of loading dose per hour) to maintain effect
*After initial atropinization: Consider atropine infusion (10-20% of loading dose per hour) to maintain effect
*'''Optimize oxygenation before giving atropine''' to reduce risk of dysrhythmias (though in resource-limited settings, do not withhold atropine waiting for oxygen)<ref name="bmj"/>
*'''Optimize oxygenation before giving atropine''' to reduce risk of dysrhythmias (though in resource-limited settings, do not withhold atropine waiting for oxygen)<ref>Eddleston M, Chowdhury FR. Pharmacological treatment of organophosphorus insecticide poisoning: the old and the (possible) new. Br J Clin Pharmacol. 2016;81(3):462-470. doi:10.1111/bcp.12784</ref>




===[[Pralidoxime]]===
===[[Pralidoxime]]===
*AKA 2-PAM
*AKA 2-PAM
*Oxime that reactivates phosphorylated AChE → primarily reverses '''nicotinic''' symptoms (weakness, fasciculations, respiratory muscle paralysis)<ref name="pralidoxime_statpearls">Bhatt MH, Bhatt S. Pralidoxime. [Updated 2023 Jul 4]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024.</ref>
*Oxime that reactivates phosphorylated AChE → primarily reverses '''nicotinic''' symptoms (weakness, fasciculations, respiratory muscle paralysis)<ref>Bhatt MH, Bhatt S. Pralidoxime. [Updated 2023 Jul 4]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024.</ref>
*'''Must give atropine BEFORE pralidoxime''' to prevent worsening of muscarinic symptoms
*'''Must give atropine BEFORE pralidoxime''' to prevent worsening of muscarinic symptoms
*'''Must be given before aging occurs''' (see [[#Aging and Oxime Window|aging table above]])
*'''Must be given before aging occurs''' (see [[#Aging and Oxime Window|aging table above]])
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*Continue until clinical improvement or patient is off ventilator
*Continue until clinical improvement or patient is off ventilator
*'''Controversies''':
*'''Controversies''':
**Evidence for benefit of pralidoxime is inconsistent; several meta-analyses have not shown clear mortality benefit when added to atropine<ref name="prognosis">Peter JV, Sudarsan TI, Moran JL. Clinical features of organophosphate poisoning: A review of different classification systems and approaches. Indian J Crit Care Med. 2014;18(11):735-745. doi:10.4103/0972-5229.144017</ref>
**Evidence for benefit of pralidoxime is inconsistent; several meta-analyses have not shown clear mortality benefit when added to atropine<ref>Peter JV, Sudarsan TI, Moran JL. Clinical features of organophosphate poisoning: A review of different classification systems and approaches. Indian J Crit Care Med. 2014;18(11):735-745. doi:10.4103/0972-5229.144017</ref>
**However, per AHA 2023 guidelines and expert consensus, oximes should still be given for significant OP poisoning, particularly when fasciculations, weakness, or paralysis are present<ref name="medscape"/>
**However, per AHA 2023 guidelines and expert consensus, oximes should still be given for significant OP poisoning, particularly when fasciculations, weakness, or paralysis are present<ref>Eddleston M, Buckley NA, Eyer P, Dawson AH. Management of acute organophosphorus pesticide poisoning. Lancet. 2008;371(9612):597-607. doi:10.1016/S0140-6736(07)61202-1</ref>
**Efficacy depends on timing (before aging), dose, and the specific OP compound involved
**Efficacy depends on timing (before aging), dose, and the specific OP compound involved
*'''Caution''': Administer slowly — rapid IV push can cause hypertensive crisis, cardiac arrest
*'''Caution''': Administer slowly — rapid IV push can cause hypertensive crisis, cardiac arrest

Latest revision as of 01:08, 21 March 2026

Decontamination

  • Providers should wear appropriate PPE during decontamination.
    • Neoprene or nitrile gloves and gown (latex and vinyl are ineffective)
  • Dispose of all clothes in biohazard container
  • Wash patient with soap and water

Supportive Care

  • IVF, O2, Monitor
  • Aggressive airway management is of utmost importance.
    • Intubation often needed due to significant respiratory secretions / bronchospasm.
    • Use nondepolarizing agent (Rocuronium or Vecuronium)
    • Succinylcholine is absolutely contraindicated
  • Benzodiazepines for seizures

Antidotes

  • Dosing with atropine and pralidoxime are time dependent and provides ability to reverse symptoms while awaiting agent metabolism
  • For exposure to nerve agents, manufactured IM autoinjectors are available for rapid administration:
    • Mark 1
      • Contains 2 separate cartridges: atropine 2 mg + 2-PAM 600 mg
      • Being phased out with newer kits
    • DuoDote
      • Single autoinjector containing both medications
      • Same doses as Mark 1: atropine 2 mg + 2-PAM 600 mg

Antidotes

Atropine

  • First-line antidote — muscarinic antagonist; treats bronchorrhea, bronchospasm, bradycardia, and secretions[1]
  • Does NOT reverse nicotinic symptoms (weakness, fasciculations, paralysis)
  • Starting dose: Atropine 1-2 mg IV (double q5min until atropinization) IV — May need 100+ mg in first 24h; endpoint is drying of secretions
  • Pediatric: Atropine 0.02-0.05 mg/kg IV (min 0.1 mg), double q5min IV
  • Doubling protocol: If inadequate response after 5 minutes, double the dose (1 → 2 → 4 → 8 → 16 mg...) until atropinization is achieved[2]
  • Massive doses may be required — total doses of 100+ mg in the first 24 hours have been reported[3]
  • Endpoints of adequate atropinization (goal of therapy):
    • Drying of bronchial secretions (most important endpoint)
    • Heart rate >80 bpm
    • Systolic BP >80 mmHg
  • Do NOT target: Fully dilated pupils, absent bowel sounds, or HR >150 — these indicate atropine toxicity[4]
  • After initial atropinization: Consider atropine infusion (10-20% of loading dose per hour) to maintain effect
  • Optimize oxygenation before giving atropine to reduce risk of dysrhythmias (though in resource-limited settings, do not withhold atropine waiting for oxygen)[5]


Pralidoxime

  • AKA 2-PAM
  • Oxime that reactivates phosphorylated AChE → primarily reverses nicotinic symptoms (weakness, fasciculations, respiratory muscle paralysis)[6]
  • Must give atropine BEFORE pralidoxime to prevent worsening of muscarinic symptoms
  • Must be given before aging occurs (see aging table above)
  • Pralidoxime 1-2 g IV over 15-30 min, then 8-10 mg/kg/hr infusion (or repeat bolus in 1 hr) IV
  • Pediatric: Pralidoxime 20-50 mg/kg IV, then 5-10 mg/kg/hr infusion IV
  • Continue until clinical improvement or patient is off ventilator
  • Controversies:
    • Evidence for benefit of pralidoxime is inconsistent; several meta-analyses have not shown clear mortality benefit when added to atropine[7]
    • However, per AHA 2023 guidelines and expert consensus, oximes should still be given for significant OP poisoning, particularly when fasciculations, weakness, or paralysis are present[8]
    • Efficacy depends on timing (before aging), dose, and the specific OP compound involved
  • Caution: Administer slowly — rapid IV push can cause hypertensive crisis, cardiac arrest
  1. Eddleston M, Buckley NA, Eyer P, Dawson AH. Management of acute organophosphorus pesticide poisoning. Lancet. 2008;371(9612):597-607. doi:10.1016/S0140-6736(07)61202-1
  2. Eddleston M, Buckley NA, Eyer P, Dawson AH. Management of acute organophosphorus pesticide poisoning. Lancet. 2008;371(9612):597-607. doi:10.1016/S0140-6736(07)61202-1
  3. Eddleston M, Chowdhury FR. Pharmacological treatment of organophosphorus insecticide poisoning: the old and the (possible) new. Br J Clin Pharmacol. 2016;81(3):462-470. doi:10.1111/bcp.12784
  4. Mitra RL, Mohan S. Anaesthesia and organophosphorus poisoning. World Federation of Societies of Anaesthesiologists. Anaesthesia Tutorial of the Week. 2011.
  5. Eddleston M, Chowdhury FR. Pharmacological treatment of organophosphorus insecticide poisoning: the old and the (possible) new. Br J Clin Pharmacol. 2016;81(3):462-470. doi:10.1111/bcp.12784
  6. Bhatt MH, Bhatt S. Pralidoxime. [Updated 2023 Jul 4]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024.
  7. Peter JV, Sudarsan TI, Moran JL. Clinical features of organophosphate poisoning: A review of different classification systems and approaches. Indian J Crit Care Med. 2014;18(11):735-745. doi:10.4103/0972-5229.144017
  8. Eddleston M, Buckley NA, Eyer P, Dawson AH. Management of acute organophosphorus pesticide poisoning. Lancet. 2008;371(9612):597-607. doi:10.1016/S0140-6736(07)61202-1