Organophosphate Toxicity

From Anvita Health Wiki

Contents 1 Etiology 2 Pathology 3 Clinical-manifestations 4 Laboratory 5 Diagnostic-procedures 6 Complications 7 Management 8 More General Terms 9 References

Etiology

• absorption through skin

Pathology

• cholinesterase inhibition

Clinical-manifestations

• bradycardia
• bronchorrhea & wheezing
• pulmonary edema
• miosis
• fasciculations, rarely seizures
• abdominal pain, nausea, vomiting, diarrhea
• urination, lacrimation, salivation, diaphoresis
• hypoxemia, confusion

• Acronyms for manifestations

• SLUDGE

• Salivation
• Lacrimation
• Urination
• Defecation
• GI upset
• Emesis

• DUMBELS

• Diarrhea
• Urination
• Miosis
• Bronchospams
• Emesis
• Lacrimation
• Salivation

Laboratory

• plasma cholinestesase & erythrocyte cholinesterase levels are < 50% of normal
• serial plasma cholinesterase activity to confirm trend towards normal

Diagnostic-procedures

• pulse oximetery
• electrocardiogram, telemetry

Complications

• patients may drown in their own secretions
• cognitive impairment with long-term exposure? [4]

Management

• general

• health care workers should be gowned & gloved
• remove patient's clothing
• shampoo hair
• clean all skin surfaces
• resolve respiratory symptoms
• do not wait for test results to start treatment in seriously ill patients

• ventilatory support as needed
• pharmaceutical agents

• atropine 0.02-0.05 mg/kg IV every 15 minutes

• treats muscarinic effects
• titrate dose to minimize dyspnea, airway resistance, & bronchial secretions

• pralidoxime 20-50 mg/kg IV every 2-12 hours

• treatment of CNS toxicity
• continuous infusion 1g/hour may be better
• addresses both nicotinic & muscarinic effects

• Duodote autoinjector ( atropine, pralidoxime)
• benzodiazepine ( diazepam, lorazepam) for seizures

More General Terms

• toxicity; poisoning; overdose

References

1. Saunders Manual of Medical Practice, Rakel (ed), WB Saunders, Philadelphia, 1996, pg 1153-55
2. Pawar KC et al, Continuous pralidoxime infusion versus repeated bolus injection to treat organophosphate pesticide poisoning: A randomized contolled trial. Lancet 2006, 368:2136 PMID: [1]
3. Medical Knowledge Self Assessment Program (MKSAP) 14, American College of Physicians, Philadelphia 2006
4. Baldi I et al. Neurobehavioral effects of long-term exposure to pesticides: Results from the 4-year follow-up of the PHYTONER Study. Occup Environ Med 2010 Nov 22 <PubMed> PMID: [2] <Internet> [3]

organophosphate toxicity