Seizures: Slattery, Prunuske Flashcards
What is a seizure?
Transient, due to excessive or synchronous neural activity of the brain.
What is the most common cause of a seizure?
Idiopathic
What are some causes of provoked seizures?
Metabolic disturbances, infections, focal neurological lesions, medication withdrawal, Toxins (ex. alcohol)
What is usually done in the ER with a first seizure?
Neuroimaging
What is done clinically for all patients?
EEG
What is needed for the diagnosis of Epilepsy?
2 unprovoked seizures at least 24 hours apart.
What does it mean that Epilepsy is a “primary seizure disorder?”
The seizure itself is the problem, as opposed to being caused by something else
What are the two big general categories of seizures and how do they differ?
Focal and Generalized. Focal is in one hemisphere, generalized is in both.
What is the difference between a simple and complex seizure?
Simple: no alteration of consciousness, Complex: impaired or loss of consciousness
In a focal (partial) seizure of the frontal lobe, what happens to the arms? Head?
Contralateral arm extension, ipsilateral arm flexion
Contralateral eye deviation and head turning
What is meant by absence?
Staring or trance-like state
what is the difference between tonic and atonic?
Tonic: stiffening, atonic: loss of muscle tone
What is meant by myoclonic?
sudden muscle jerks
What is Status Epilepticus?
> 5 min of continuous seizure activity,
or
Recurrent seizure activity without recovery to baseline between seizures
How do you treat Status Epilepticus?
IV Benzodiazepine (Lorazepam)
What are the drugs of choice for focal, local (simple partial) seizures?
Carbamezepine and Levetiracetam
What are the drugs of choice for Focal, with contralateral propagation or secondary generalization (complex partial)?
Carbamezepine and Levetiracetam
What is the drug of choice for Generalized non-convulsive (absence)?
Ethosuximide
What are the drugs of choice for Convulsive (tonic-clonic, atonic, others)?
Valproic Acid and Levetiracetam
Do you retain awareness in a simple partial seizure?
Yes
In the grand scheme of things, what is the pathogenesis of a seizure?
Too much excitation, too much Glutamate, too little GABA
An increase of what extracellularly can decrease neuronal hyper polarization?
K+
What may increase neuronal excitability?
A decrease in extracellular Ca+ and Mg2+
What is a paroxysomal depolarization shift?
High frequency burst of action potentials
What is an Interictal spike?
The initial spike that starts the seizure course, followed by a decrease of activity.
What does the location of an interictal spike tell us?
The location of the interictal spike helps localize the brain region from which seizures originate in a given patient
What are the two things we can do via anti-seizure drugs?
- decreases in the effectiveness of GLU transmission and/or
2. increases in the effectiveness of GABA transmission will prevent/treat seizure
What is the molecular target for Levetiracetam?
Synaptic vesicle proteins (SV2A) in both Glutamate and GABA presynaptic neurons
What are the two molecular targets for Valproic acid?
NMDA receptor and GABA transaminase
What drug works on the GAT-1 GABA transporter on a glia cell?
Tiagabine
What drugs work on the AMPA receptor on the postsynaptic cell of glutamate transmission?
Phenobarbitol and Topiramate
Where does Ethosuximide work?
VG Ca+ channels (presynaptic Glutamate neuron)
Where does Carbamazepine work?
VG Na+ Channels presynaptic Glutamate neuron
