Anesthesia, Seizures, and PD

• Generalized seizures = entire brain is involved
• Focal seizures = specific parts of the brain are involved
• Antiseizure drugs = antiepileptic drugs (AEDs) = anticonvulsants
• All anti seizure meds suppress neuron excitability
• Peripheral sensitization is when receptors at the site of injury become increasingly responsive or threshold for noxious stimulus decreases = hyperalgesia
• Central sensitization is when pronlonged peripheral inflammation or inflammation of theCNS results in increased excitability in the dorsal horn and decreased inhibition via descending pathway = allodynia
• Major side effects of anti epileptic drugs

  • liver toxicity
  • blood dyscrasias - different levels of cells in your blood
  • aplastic anemia
  • agranulocytosis
  • birth defects
• 60-70% of patients remain seizure free after meds are withdrawn
• Criteria for removing medications for seizures

  • free of seizures for 2 years while on meds
  • good control of seizures within first year of the seizure occurring
  • initial seizure is in childhood
• In PD, Ach and dopamine are out of balance in the basal ganglia = Ach increasing inhibition leading to bradykinesia
• Low protein diet when taking Sinemet because proteins break down into amino acids which compete for absorption with Sinemet
• Levodopa "Drug Holiday" not recommended anymore

  • can lead to severe immobility
  • DVT
  • PE
  • Pneumonia
• all anti seizure drugs suppress the excitability of neurons that start the seizure
• First generation anti seizure drugs

  • barbituates
  • benzodiazepines
  • hydantoins
  • iminostibenes
  • succinimides
  • valproates
• What first generation drug potentiate inhibitory effects of GABA; decreases excitatory glutamate?

  Barbiturates

  • phenobaribital = most common in developing countries
• What first generation drug inhibits effects of GABA?

  Benzodiazepines

  • clonezepam
  • diazepam (valium)
  • lorazepam
• What first generation drug blocks sodium channels in rapid fire neurons; may influence potassium and calcium channels, may increase concentration of GABA?

  Hydantoins

  • fosphenytoin
  • phenytoin (Dilantin)
• What first generation drug are similar to hydantoins; may inhibit norepinephrine, NOT usually sedative?

  Iminostibenes

  • carbamazepine (Tegretol)
  • oxcarbazepine (trileptal)
• What first generation drugs affect the calcium channels; inhibits spontaneous firing in thalamic neurons?

  succinimides
• Dilantin is non-sedative
• What second generation drug is for partial seizures in adults and children over 3?

  gabapentin (neurontin)
• what second generation drug is for partial seizures over age 16; adjunct with generalized seizures?

  lamotrigene (Lamictal)
• what second generation drug is for partial seizures in adults; tonic-clonic seizures >6 years old?

  levetiracetam (Keppra)