What are potential routes for organophosphate/carbamate exposure?
-dermal
-oral
-pulmonary absorption
Which products contain organophosphates and carbamates?
insecticides:
-sprays
-pour-on
-oral agents
-baits
-collars
-dips
What are the clinical signs of organophosphate/carbamate toxicity?
*muscarinic:
-defecation
-urination
-miosis
-bradycardia
-emesis
-lacrimation
-salivation
*nicotinic:
-tremors
-paresis
-paralysis
-mydriasis
-inc. HR
*CNS:
-anxiety
-hyperactivity
-seizures
-coma
What are the characteristics of organophosphate/carbamate intermediate syndrome?
-can occur 8 hours to 4 days post-exposure
-nicotinic receptor fatigue
-cholinergic downregulation
-muscle weakness of neck, thoracic limbs, resp. muscles
-can last days to week
Which diagnostics are done in cases of organophosphate/carbamate toxicity?
*CBC/CHEM:
-non-specific changes
*RBC or plasma cholinesterase activity
-less than 50% suspicious; less than 25% diagnostic
*analysis of gastric contents
What are the treatment steps for organophosphate/carbamate toxicity?
-emesis or gastric lavage
-AC
-bathing
-seizure control
-oxygen/mechanical ventilation
-atropine
-pralidoxime chloride (antidote)
What are the characteristics of pralidoxime chloride?
-antidote for organophosphates only
-combats nicotinic signs by reactivating AchE
-want to use early
What are the characteristics of pyrethrins?
-extract of the chrysanthemum flower
-pyrethroids are synthetic derivatives
-found in sprays, shampoos, dips, collars, and spot-on treatments
What are the clinical effects of pyrethrins?
-ptyalism
-vomiting
-diarrhea
-tremors
-hyperexcitability
-depression
-seizures
-coma
-mydriasis
-transient blindness
-severe hyperthermia
What are the management steps for pyrethrins?
-GI decontamination ONLY if a collar or tag
-bathing
-topical vitamin E oil
-methocarbamol
-seizure control
-IV fluids
-ILE
What are the sources of metaldehyde?
-slug and snail baits
-solid fuel for camp stoves
What are the clinical findings in metaldehyde toxicity?
-signs within a few hours
-anxiety/panting
-tremors
-ataxia
-nystagmus
-seizures
-hypersalivation
-vomiting
-diarrhea
-hyperthermia
-multi-organ dysfunction
What are the treatment steps for metaldehyde toxicity?
-emesis or gastric lavage
-AC
-IV fluids
-active cooling
-methocarbamol
-aggressive seizure control
-ILE
-ECT/dialysis
Which rodenticides are anticoagulants?
-brodifacoum
-bromadiolone
-diphacinone
-chlorophacinone
How do anticoagulant rodenticides work?
-inhibit vitamin K-epoxide reductase
-depletion of active vitamin K1
-decreased production of factors 2, 7, 9, and 10**
What are the clinical signs of anticoagulant rodenticide toxicity?
-bleeding anywhere in body
-lethargy
-weakness
-pale gums
-tachycardia
-coughing
-dyspnea
-hemoptysis
-swelling post venipuncture (hematoma)
-lameness
-scleral hemorrhage
-ataxia
-seizures
-vestibular signs
Which diagnostics are done in cases of anticoagulant rodenticide toxicity?
*PT/PTT testing
-PT will be prolonged first
-36 to 48 hours post-exposure
*ACT
-screening test
-prolonged 3 days post-exposure
*rodenticide panel
-whole blood or tissue sample
What are the treatment options for acute, asymptomatic anticoagulant rodenticide toxicity?
*decontamination
-emesis or AC
*option 1:
-monitor at home
-check PT in 36 hours
*option 2:
-vitamin K1 supplementation for 30 days
-check PT 36hrs after last dose
What are the treatment options in cases of symptomatic anticoagulant rodenticide toxicity?
-oxygen +/- thoracocentesis
-vitamin K1
-blood products (plasma, packed RBCs, autotransfusion)
What are the possible brand names of bromethalin rodenticide?
-tomcat
-assault
-terminator
-fastrac
-gladiator
-rampage
What are the characteristics of bromethalin?
-lipid soluble; goes to fat and brain
-extensive enterohepatic recirculation
-poor prognosis with severe signs
What are the clinical signs in bromethalin paralytic syndrome?
-signs in 1 to 7 days
-vomiting
-tremors
-ataxia
-paresis/paralysis
-signs resolve within weeks
What are the clinical signs in bromethalin convulsant syndrome?
-signs in 4 to 18 hours following acute, large vol. ingestion
-severe muscle tremors
-hyperesthesia
-hyperthermia
-hyperexcitability
-seizures
-death
What are the treatment steps for bromethalin toxicity?
-emesis
-multi-dose AC
-IV fluids
-close monitoring of Na conc.
-ILE
-mannitol
-anticonvulsant therapy
