Seizures Flashcards
1
Q
Seizure
A
episode of abnormal neurologic function caused by abnormal electrical discharge of brain neurons
2
Q
Epilepsy
A
condition of recurrent seizures, usually due to fixed condition
3
Q
Seizure Mechanism
A
- Increased cell membrane excitability due to failure of normal inhibitory mechanisms (GABA)
- Leads to intense, prolonged neuronal discharges
- May remain localized or may spread to involve entire cortex
4
Q
Generalized Seizures
A
- Near-simultaneous activation of entire cerebral cortex
- Causes abrupt LOC
- Grand Mal, Petit Mal (Absence), Myoclonic
5
Q
Grand Mal Seizure
A
- tonic-clonic seizure
- begin with abrupt LOC, usually without warning
- patient falls to ground with trunk/extremities extended (tonic phase)
- rhythmic jerking of trunk and extremities (clonic phase)
- often apnea, cyanosis, tongue-biting, urinary incontinence
- typically lasts 60-90 seconds
- Post-ictal phase: follows seizure, pt remains unconscious, flaccid, confused, usually for many minutes before slowly regaining consciousness
- Todd’s paralysis: may occur after seizure, transient postictal focal paresis
6
Q
Petit Mal (Absence) Seizure Features
A
- typically very brief (few seconds)
- abrupt LOC
- blank stare
- eyelids may twitch
- no response to voice
- no falls, no involuntary movement, no incontinence
- no post-ictal phase, attacks cease abruptly, patient unaware that anything happened
- may be frequent (>100/day)
- school-aged kids, often resolve as child gets older
7
Q
Myoclonic Seizures
A
- LOC associated with isolated extremity jerking
8
Q
Partial (Focal) Seizures
A
- simple partial, complex partial
- due to electrical discharges beginning in localized region of brain
- may remain localized or may spread, becoming generalized
- often due to focal structural brain lesion (e.g. tumor, AVM, scar tissue, CVA, head injury
9
Q
Simple Partial Seizure
A
- NO alteration of consciousness
- Manifestations may be:
- motor: tonic or clonic movements, often unilateral, often limited to one extremity
- sensory: paresthesias/numbness, flashing lights, olfactory/gustatory hallucinations
10
Q
Complex Partial Seizures
A
- psychomotor seizure, temporal lobe seizure
- involves change in level of consciousness or mentation
- usually bizarre symptoms with psychic features
- visceral sx (nausea, butterflies in stomach)
- hallucinations (visual, olfactory, auditory, gustatory)
- memory disturbances (deja vu, jamais vu)
- dream-like states
- automatisms: repetitive, purposeless movements (lip-smacking, playing with clothes)
- affective disorders (paranoia, depression, elation)
11
Q
Seizure Mimics
A
- syncope: premonitory feeling of “going to black out”, graying of vision, quick recovery of consciousness
- narcolepsy: brief attacks of uncontrollable daytime sleepiness
- movement disorders: (tics, jerks, tremors) consciousness preserved, movements involuntary but pt can usually suppress them
- hyperventilation syndrome: gradual onset with SOB, anxiety, numbness of mouth/extremities, maybe LOC
- psychogenic seizures
12
Q
Psychogenic Seizures
A
- pseudoseizure
- often occur in response to emotional upset
- often occur only when witnesses present
- bizarre features, often with variable presentation
- pts protect themselves from noxious stimuli
- no incontinence or injury during episode
- no post-ictal confustion
- normal EEG during attack
13
Q
Status Epilepticus
A
- continuous seizure activity lasting >5 min
- two or more seizures without return of consciousness between
- usually tonic-clonic seizures, but may also be simple partial, complex partial, absence
- 50% have no prior seizure history
- demands urgent treatment
- hypoxia >30-60min, leads to permanent neuro injury
- 10% mortality
14
Q
Causes of Status Epilepticus
A
- CNS infection
- Trauma
- Anoxia
- Noncompliance or change in anticonvulsant meds
- Stroke
- Metabolic derangements
