Types of Seizures Flashcards
Causes of nonepileptic seizures
Extreme metabolic disruption from systemic disease
A deficiency state
Local effects of a brain tumor
Withdrawal from sedative/hypnotic drugs including ethanol
Infection
Renal failure
Hypoxic encephalopathy
Febrile convulsions
How do epileptic seizures happen?
A group of abnormal neurons in the epileptogenic foci spontaneously depolarize and the foci will recruit normal neurons –> seizure
Details about seizure activity patterns
Consists of a set of sensory, mental, and/or motor activities that are fairly consistent for a given individual
Partial seizures begin at…
…discrete and relatively limited focus
The pattern of partial seizures depends on what?
The area stimulated
Focal motor without march definition
Twitching limited in one area and doesn’t spread
Focal motor with march definition
Twitching starts in one area and spreads
Characteristics of a simple partial seizure
Has limited spread. Uncomplicated, affects only limited aspects of neural function, has motor or sensory symptoms
(The example Gengo gave in lecture where the patient said the room smelled weird but Gengo said it was fine, the patient realized they had a simple partial seizure)
Are consciousness and memory disturbed in a simple partial seizure?
No
Characteristics of complex partial seizures
Alteration of consciousness follows initial simple seizure. May appear alert and aware but consciousness impaired
Typically appears confused or preoccupied
May exhibit automatisims: purposeless and automatic behaviors (lip smacking, sucking, fumbling with clothing, etc.)
Where do complex partial seizures usually arise?
Temporal lobe
Feature of a generalized seizure (in regard to how much of the brain is involved)
Can’t be linked to a single foci, involves entire cerebrum. Includes seizures that vary immensely in terms of severity and amount of brain tissue recruited
Absence seizure features
Minor impairment of neural function because of short duration
Blank stare or other facial expression indicates impaired consciousness
2-10 seconds later- resumes pre-seizure activity
Disruption in intentional behavior, consciousness, and memory but not posture, muscle tone, or ongoing automatic behavior (walking)
May include lip smacking, pouting, eye blinking
Can occur 100s of times/day
When do simple absence seizures occur?
Childhood and adolescence, begins in childhood and peaks at 6-7 y/o
Do simple absence seizures resolve?
Yes, they usually go away when the CNS matures but may progress to generalized tonic-clonic seizures
Feature of a tonic-clonic seizure (in regard to how much of the brain is involved)
All brain systems can be recruited into paroxysmal discharge
3 phases of a tonic-clonic seizure
Tonic phase
Clonic phase
Terminal phase
Tonic phase features
Brief period of muscle flexing followed by 10-15 seconds of pronounced extension, bladder may empty, breathing stops, pupils unresponsive to light
End indicated by short period of muscle tremor
Clonic phase features
Onset indicated by initial muscle relaxation
Violent spasms of contraction and relaxation
Strongest muscles dominate- elbow flexion, leg extension, torso hyperextension
Respiration resumes but ineffective- cyanosis
Heavy saliva secretion and blood from bitten tongue → froth of blood in mouth
Terminal phase
Limp and quiet with normal breathing
May be followed by several hours of deep sleep or may become conscious with no recollection of seizure
Seizure definition
uncontrolled electrical activity in the brain, that can produce a physical convulsion, minor physical signs, thought disturbances, or a combination of these symptoms
Epilepsy definition
condition characterized by a relatively long-term disturbance of brain structures and/or function that produces an increased susceptibility to seizures
Difference between a person who has epilepsy vs. seizures
Everyone who has epilepsy has seizures, but not everyone who has a seizure has epilepsy
Common causes of seizures in adults 20-50 y/o
Possible it could be from underlying causes like metabolic imbalances, toxicity, hemodynamic instability, psychogenic (patient thinks they’re having a seizure but they’re really not)
Common causes of seizures in adults >50 y/o
Usually from a tumor, bleeding, infection, fibrosis secondary to a stroke that occurred 6-12 months earlier…usually don’t have a good prognosis
Seizure history
When was your first seizure?
How often do you have seizures?
When was your most recent seizure?
What did you do, or eat, or take the day of your most recent seizure?
What anticonvulsant medications have you used in the past?
What medications are you currently taking in addition to the anticonvulsant?
Medication-specific questions regarding toxicity
Determine relevant counseling points for this patient and their specific medications
Be sure patient understands the goal of therapy
Management of epilepsy
Control with one drug, only go to polytherapy only after several drugs have failed
Goal of epilepsy therapy
Reduce the number of seizures (NOT GET RID OF THEM ENTIRELY) and have the patient experience the least amount of side effects
Favorable outcomes of seizure therapy
Seizure free >3 years
Monotherapy
Background EEG normal
No psychomotor retardation
No juvenile myoclonic epilepsy
Who should diagnose epilepsy?
A NEUROLOGIST
What to do if a pregnant patient has seizures and needs therapy
Use AED monotherapy if necessary at the lowest dose
AEDs to avoid in pregnancy
Lamotrigine
VPA+CBZ+PB polytherapy
Avoid VPA and CBZ but if not, use lower divided doses
Patients taking OCs but also have seizures
Divalproex has no effect on OC efficacy
What medications decrease OC effectiveness and why?
phenobarbital, phenytoin, primidone, carbamazepine all decrease it because they increase the CL of estrogen
AEDs that are CI’ed in breastfeeding
Ethosuximide, zonisamide, clonazepam, diazepam
