Neuro: Seizures and Seizure management Flashcards
Define seizure
Clinical manifestation of excessive hypersynchronous neuronal activity
(inadequate inhibition (GABA), excessive excitation (glutamate), or both)
What is a cluster seizure?
2 or more seizures within 24 hours, with return to consciousness between seizures
What is status epilepticus?
- Seizures lasting > 5 mins
- Or 2 or more seizures without recovery to consciousness between seizures
What is pharmacoresistant epilepsy?
Failure to achieve freedom of seizures despite adequate trials or 2 or more AED drugs
How are seizure types classified?
- Generalized “Grand mal”
- Focal “Petit mal”
- Focal with secondary generalization (most common)
What is the most common seizure type?
A. Generalized “Grand mal”
B. Focal “Petit mal”
C. Focal with secondary generalization
C. Focal with secondary generalization
What are the characteristics of a generalized seizure?
- Bilateral involvement and loss of consciousness
- Salivation, urination, or defecation
- Typically lasts < 3 mins
- Presents as tonic, clonic, or tonic-clonic
What are the characteristics of a focal seizure?
- Ictal onset consistent from 1 seizure to another
- Electrical activity arises from opposite hemisphere (if lesion in L hemisphere, R side affected)
- Difficult to asses consciousness
- Lateralized or regional signs
- Tonic, clonic, tonic-clonic, or atonic on 1 side
- Salivation, urination, defecation
- Behavior changes: acting like seeing/feeling something
What are the 3 components of a seizure?
- Pre ictal phase (before seizure)
- Ictal phase (during seizure)
- Post ictal phase (after seizure)
What can occur in the pre-ictal phase of a seizure?
Confusion, hiding, attention seeking, acting weird before the onset of seizure
How long does the pre-ictal phase tend to last?
minute to hours prior to seizure
How long does the post-ictal phase tend to last?
minutes to days
What can occur in the post-ictal phase of a seizure?
- Behavior changes
- Neuro symptoms
- May be the only sign a patient had a seizure
Other than factors that precipitate stress, what physiological parameter in dogs make them more at risk for seizures?
Intact females in estrus
What are the etiology based classifications of epilepsy?
- Idiopathic
- Structural
- Reactive
What dog breeds are susceptible to idiopathic epilepsy?
- Australian Shep
- Border collie
(poor treatment response)
What factors are supportive in the diagnosis of idiopathic epilepsy?
- Seizures begin between 6m-8yrs
- Normal, conscious PE between seizures
- Normal diagnostic testing
What is structural epilepsy?
- Seizures due to brain pathology (DAMNITV)
(Degenerative, Anomalous, Metabolic, Neoplastic, Inflammatory, Traumatic/Toxic, Vascular)
How can the diagnosis of structural epilepsy be achieved?
- MRI
- CSF
- Biopsy/Necropsy
- DNA testing
What etiology-based classification of seizures is refractory to treatment in 25% of cases?
Idiopathic epilepsy
List some differentials for other diseases or symptoms that look like seizure activity, but are not true seizures
- Syncope
- Vestibular disease
- Compulsive disorders/Panic attacks
- Head tremors, neck pain
- Toxicity
- Neuromuscular diseases
- Narcolepsy, catalepsy, REM sleep disorder
- Feline hyperaesthesia syndrome
When is starting anticonvulsant therapy indicated in a patient?
- Identifiable structural lesion, or prior history of brain dz or injury
- Acute repetitive seizures or status epilepticus
- 2 or more isolated events within 6 months
- Prolonged, severe or unusual post- ictal events (Ex: aggression)
What are the goals of emergency seizure treatment?
- Stop seizure
- Prevent next seizure
- Decrease frequency
- Consider pharmacodynamics of drug choice (half life, MOA, route of admin, etc)
What drugs can be used in emergency treatment for controlling seizures?
Benzos - 1st line DOC
1. Midazolam
2. Diazepam
3. Lorazepam
2nd line AEDs
4. Levetiracetam
5. Phenobarbital