steps of seizure hx
ask about
- before (long before, days before, hours and minutes before)
- during
- after
what to ask about long before seizure
- pregnancy
- development
- febrile convulsions
- meningoencephalitis
- head trauma
- PMHx of seizures
- FHx of seizures
what to ask about days before seizure
- medication nonadherence
- provoking factors
- sleep deprivation
- systemic illness
what to ask about the hours, minutes before seizure
- provoking factors
- prodrome
- aura
what to ask about the ‘‘during’’ of the seizure
need info from WITNESS***
- level of consciousness
- duration of ictus (ictus = alteration of consciousness)
- automatisms
- head and eye deviation
- skin colour
- stiffness
- convulsions
- urinary incontinence
- tongue biting
- frothing/hypersalivation
what to ask about after the seizure
- post-ictal confusion (yes, no, how long, to what degree)
- fatigue
- sleepiness
- headache
- muscle soreness
- focal weakness
ddx of LOC (in general, not just STIC LOC = sudden transient isolated complete LOC) or altered consciousness or seizure like symptoms (possibly with no alteration of consciousness)
- seizure
- syncope
- pseudoseizure
- migraine with aura
- TIA (transient ischemic attack)
- hypoglycemia
- narcolepsy (cataplexy)
- anxiety (hyperventilation, panic)
what in the seizure hx will tell you that it was really a syncope
-before = dimming or blurring of vision (note this may point to vaso-vagal syncope specifically)
-during = pallor + limp muscles (in seizure, are rather stiff)
-after = no post-ictal confusion
________________
ask the observer:
1. colour of patient
2. was there an emotional triggering event
how can an aura help you in seizure hx
- tells you there is a focus of epilepsy (doesn’t mean focal. can be focal or secondary generalized depending on hx you get from pt)
- tells you in what part of the cortex the focus is (visual aura vs sensory vs motor, etc.)
ictus def
alteration of consciousness
2 good Qs to ask to discern seizure vs syncope
- colour of patient
- was there an emotional triggering event
* *ask the observer**
syncope specialists
often no specialist, may refer to cardiology if is cardiac subtype (cause of STIC LOC)
pseudoseizure def
- looks like seizure
- no underlying epileptic activity when monitor brain waves on EEG
- stress is manifesting in physical way
pseudoseizure specialists
psychiatry
3 ddx of LOC in general that are specific to neurology
- migraine auras
- seizures
- TIAs
main thing for diff migraine auras vs seizures vs TIA
tempo and progression.
- migraine aura = gradual onset, seizure = gradual or abrupt, TIA = abrupt
- seizure duration of sx = < 1 min, TIA and migraine aura = 15-60 min
- migraine aura = slow spread, seizure = rapid spread, TIA = all symptoms at once
- migraine aura and seizure recur with same pattern, TIA doesn’t recur with identical symptoms
- migraine aura = headache, TIA and seizure = no headache
- migraine aura and seizure = positive sx (visual = flashing or sparkling of light, sensory = tingling), TIA = negative sx (visual = complete loss of vision, sensory = numbness)
recommended investigations in first seizures
- brain imaging (CT or MRI)
- EEG
- blood tests (blood counts, serum glucose, electrolytes) for reversible causes
- urine toxicology screen
- CSF LP (lumbar puncture) if infection (encephalitis or meningitis) suspected
provoked vs unprovoked seizure def
provoked = what caused this seizure will cause a seizure in anyone (like enough hyponatremia)
provoked vs unprovoked first seizure prognosis
provoked much less likely to recur
RFs for seizure recurrence
- pre-existing neuro condition
- partial focal seizure
- nocturnal seizure
- abnormal neuro exam, EEG OR MRI
- FHx of seizures
- age <16 or>59
- status epilepticus
first seizure management (tx)
NO strict guidelines. depends on RFs for recurrence, risk of injury, risk of stigma, occupational hazards \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ usually not tx with anticonvulsants IF -no RFs for recurrence -normal neuro exam -normal imaging -normal EEG
prognosis of a second seizure
the risk of recurrence is 75%
second seizure management (tx)
initiate AED for sure
principles of AED choice
- select most efficacious AED for the seizure type or epilepsy syndrome
- consider unique pt and AED drug charact MOST IMPORTANT PART
- consider convenience (posology)
- consider cost (with pt). 2nd gen AED more $ than 1st gen
- monotherapy (1 AED) is preferred
- drug levels are only a guide
some 1st gen AEDs
- valproic acid
- CBZ
- clonazepam
- phenobarbital
- phenytoin
- diazepam
some 2nd gen AEDs
- gabapentin
- lacosamide
- lamotrigine
- levetiracetam
- oxcarbazepine
how to select most efficacious AED for the seizure type or epilepsy syndrome: some examples
- complex partial = CBZ (tegretol)
- secondary generalized = CBZ
- primary GTC = valproic acid, lamotrigine
how to consider unique pt and AED drug charact MOST IMPORTANT PART
- some AEDs can help for another sx, dz
- some AEDs have to be avoided in certain dz or populations of pts
why prefer monotherapy in AEDs
more AEDs = more risk of adverse effects
why drug levels of AEDs are only a guide
- if need better control, can give a bit more than maximum if no adverse effects
- if seizures controlled, can give a bit less than minimum
- PREFER BOOSTING DOSE over increasing nbr of AEDs
(EXAM) 4 common AEDs
- phenytoin (Dilantin)
- carbamazepine (Tegretol)
- valproic acid (Epival)
- levetiracetam (Keppra)
(EXAM) phenytoin (Dilantin) indication, SEs, adv and disadv
- focal (partial) AND generalized
- SE = rash
- adv = once a day + can be given IV as well (not just oral)
- disadv = enzyme induction (interferes with hepatic enzymes, careful if pt takes other meds)
(EXAM) CBZ (tegretol) indication, SEs, adv and disadv
- focal (partial) ONLY
- SE = rash, hyponatremia
- adv = well tolerated
- disadv = enzyme induction
(EXAM) valproic acid (epival) indication, SEs, adv and disadv
- generalized ONLY
- SE = tremor, weight gain
- adv = effective
- disadv = neural tube, congenital defects CAN’T GIVE TO WOMEN OF CHILD-BEARING AGE
(EXAM) levetiracetam (keppra) indication, SEs, adv and disadv
- focal (partial) AND generalized
- SE = psychiatric
- adv = no interactions (metab renally, not in liver)
- disadv = less effective
reasons for recurrent seizures after AED tx (‘‘refractory’’ seizures)
- provoking factors
- poor adherence (common reason is SE)
- wrong med
- wrong dx (focal vs generalized = diff tx)
principles of tx ‘‘refractory’’ seizures
- maximize the dose of one med as long as the dose is tolerated. when really at the max and no control, add new agent.
- when add agent B, taper agent A once seizures are controlled. means increase med B gradually and decrease med A gradually if B helps) one or introducing
what MRIs can show that CTs don’t show
- mesial temporal sclerosis (scarred region in temporal lobe, bright on MRI. removed = curative)
- malformations of corticol developmental (focal cortical dysplasia)
- etc.
what CT helps for in imaging and what’s relevant to seizure
- done in patients with first seizure
- gives gross image of the brain
- can detect: big strokes, big tumors, bleeding in the brain