Epilepsy Flashcards
Is consciousness lost during a partial seizure?
NO; epileptic d/c consists of repetitive firing of a few cortical neurons; confined to a specific cortical area or focus
simple partial seizure clinical manifestation
-functionally related to cortical area involved by neuronal discharge
-seizure in L frontal motor cortex=rhythmical contractions or jerking of R. face, arm, and leg for 1-2min
(b/c neuronal d/c doesn’t spread or generalize diffusely pt can speak/follow commands d/r spell, remains conscious, is fully aware; recalls event, does not appear confused)
what are some other symptoms of simple partial seizures?
localized sensory, visual, or autonomic (sweating, flushing, nausea) disturbances WITHOUT loc
is consciousness lost d/r a complex partial seizure
YES; d/t b/l neuronal d/c usually in the medial TEMPORAL or hippocampal areas
-pt cant follow commands d/r spell, after event has NO recollection, appearing confused for a brief period (POST-ICTAL phase)
automatisms in complex partial seizures
semi-purposeful, stereotyped gestures or “automatic movements”: chewing, finger tapping, uttering short phrases, wondering about
what can happen with both simple partial and complex partial seizures
they can secondarily spread or generalize diffusely to other b/l cortical areas causing loc…motor cortex usually involved=rhythmical vigorous jerking of trunk and limbs
- there is a post ictal phase
- pt doesnt remember the generalized convulsion
- BUT may recall inititating symptoms (aura)
What happens in many secondarily generalized seizures that confuses categorization
focal d/c spreads so rapidly pt cant recall a specific aura and sz appears to be a generalized convulsion
primarily generalized seizures
occur when an electrical d/c simultaneously arises from widespread, b/l areas of cerebral cortex
what are the two types of generalized seizures (1/2)
- absence seizures of childhood=non convulsive primarily generalized; last several seconds, occur many times daily
- brief impairment of consciousness; no postictal confusion or recall of event
- 3hz spike and slow wave electrical discharge - generalized tonic clonic (convulsive) sz
what are the two types of generalized seizures (2/2)
- absence seizures of childhood
- generalized tonic clonic (convulsive) sz
- LOC, fall to ground, injuries
- can be 2/2 primarily or secondarily generalized cortical d/c
- aura may be recalled which is actually a simple partial thats generalizing
phases of a generalized tonic clonic (convulsive) sz
a. tonic phase-sudden stiffness from contraction of limb and trunk muscles
- apnea leads to a cyanotic dusky face and consciousness is lost
b. clonic phase-happens seconds after tonic
- rhythmic forceful synchronous jerking of limbs and face, oral trauma, xs drooling
c. post-ictal phase (5-15mins)-bladder incontinence may be noted; pt sleepy, confused, unavle to recall what happened
Why is the post ictal phase important
If sz wasnt observed it is important clue that consciousness was lost from a preceding sz and not from syncope or fainting
what is epilepsy
tendency or predisposition for seizures to recur
primarily generalized sz are a result of?
global synchronous cortical discharge from diffuse cortical disinhibition
- disinhibition may be due to:
- –diffuse, permanent brain injury (anoxia, hereditary metabolic d/o, congenital brain malformations)
- –transient metabolic disorders (cocaine, EtOH withdrawal, tetanus, electrolyte disturbances )
secondarily generalized seizures are a result of?
- cortical discharge that begins at a focus, the site of an acquired lesion
- lesion may be d/t: head trauma (recent/remote), viral encephalitis, stroke (hemorrhage or infarction), or tumor
- may be super quick and appear to be primary, so always check for focal lesion
non-epileptic pseudoseizures
- may appear as episodic jerking or thrashing movements without spontaneous cortical discharge
- noted in pts with h/o depression, physical abuse, and real epilepsy
diagnostic testing for seizures
- MRI (way better than CT)
- EEG-chances of recording a sz are inc by sleep deprivation, hyperventilation, phonic stimulation (flashing lights)
tx of seizures
- start with one anticonvulsant at a time
- the drugs enhance cortical inhibition by: affecting sodium or calcium channels, acting as GABA analogues, or a combo
Valproate, Lamotrigine, BZ
- treat many sz types:
- –primarily generalized convulsive or nonconvulsive (absence)
- –partial sz
- –secondarily generalized sz
Ethosuximide
effect for absence seizures
*What are side effects of anticonvulsants?
- at high serum levels: confusion, somnolence, ataxia (+nystagmus, dysarthria, dysmetria)
- at minimal serum levels: teratogenicity
epilepsy surgery
-use EEG to id seizure focus which is then surgically resected
generalized tonic-clonic (convulsive) STATUS epilepticus
- continuous, unabated seizure or series of repeated seizures from which the pt doesnt recover, for a period of 30 mins or longer
- neurological emergency
consequences of status
-if it persists for a long time pts can have permanent deficits of memory or cognition
what do pts in STATUS require
- emergent life support measures
- -mechanical ventilation and oxygenation
- -immediate correction of any hypoglycemia
drug of choice for STATUS
Benzo such as diazepam or lorazepam d/t their rapid onset of action…longer-acting anticonvulsants are added later
LUMC protocol for treating generalized STATUS epilepticus
- Lorazepam 0.1mg/kg (4-8mg) as an IV bolus, repeatable in 5-10 mins
- Phenytoin 20mg/kg IV, given in saline no faster than 50mg/min (OR…fosphenytoin 20 phenytoin equivalents/kg IV no faster than 150mg/min)
focal seizures
-caused by abnml neuronal discharges originating in a single hemisphere
how can focal seizures present
- motor (head turning)
- sensory (paresthesias)
- autonomic (sweating)
- impairment of consciousness and automatisms (chewing)
what should raise suspicion for seizure
- sudden loc
- l/o postural tone
- delayed return to baseline mental status (d/t postictal state of transient confusion, lethargy, and/or focal neurologic deficits)