Flashcards in Epilepsy Deck (22):
Recurrent spontaneous intermittent excessive electrical activity in part of brain causing seizure.
Often idiopathic, possibly due to channelopathies.
Structural- cortical scarring, developmental, SOL, stroke, sclerosis, vascular malformation.
Various types of seizure, see other cards.
In general distrubed conciousness, behaviour, emotion, motor function, sensation.
Acutely may need paralysis and intubation.
One hemisphere, focal onset with site specific features.
-Simple- retain awareness, often precursor to larger seizure (aura). Focal motor, sensory, autonomic or psychic symptoms.
-Complex- lose awareness, odd behaviour eg lip smacking. Commonly temporal lobe= post ictal confusion.
-Secondary generalisation- electrical disturbance starts focal and spreads widely.
General symptoms eg amnesia, los bladder tone. Headache, drowsy.
Frontal lobe partial seizure
Abnormal head movement
Swearing and shouting
Repeated movements eg rocking
Temporal lobe partial seizure
Strange taste or smell
Rising sensation in stomach
Lip smacking, swallowing, chewing
Parietal lobe partial seizure
Feeling like body part missing
Cant understand language or reading
Occipital lobe partial seizure
Both hemispheres so cross corpus callosum. Simultaneous throughout cortex. Impaired conciousness.
-tonic clonic- LOC, stiffen, jerk, loss bladder control, tongue bite, respiratory arrest. Post ictal confusion and drowsy.
-atonic- sudden loss tone, no LOC.
-myoclonic- sudden jerking limb, face or trunk.
-absence- under 10 seconds. Unresponsive pause. May be blinking or slight jerking. Often in kids.
Triggers? Eg photic and hyperventilation.
EEG supports diagnosis only.
Check bloods, glucose, electrolytes, LFT, UE, ECG.
AED depends on type
-VGSC blocker eg carbamazepine, phenytoin, lamotrigine.
-benzodiazepine GABA enhancement.
-valproate decrease GABA breakdown and increase synthesis.
Emergency management if over 5 mins-
IV lorazepam, IV phenytoin.
Look for cause eg drug, withdrawal, electrolytes, infection.
Surgery if very severe.
-Non epileptic causes-
Alcohol or benzo withdrawal
Hypoxia, electrolytes, glucose, urea
Infection eg meningitis, syphillis, HIV
Drugs eg TCA, cocaine, tramadol, theophylline.
AED in pregnancy
Lomotrigine safest, including during breast feeding.
AEDs by seizure type
-generalised tonic clonic- valproate or lamotrigine 1st line. Then carbamazepine.
-absence- valproate, lamotrigine, ethosuximide.
-other generalised eg atomic, myoclonic- same as tonic clinic but NOT carbamazepine.
-partial- carbamazepine 1st line. Then valproate, lamotrigine etc.
Aim for monotherapy. Start low dose.
Status epilepticus convulsions over 5 mins. Tx with IV lorazepam or phenytoin.
Brain dysfunction or damage.
Important benzo points
Lorazepam for status epilepticus
Clonazepam for absence ST
AE- sedation, tolerance, confusion, lack coordination, agression, dependance, withdrawal can trigger seizure.
OD reversed by IV flumazenil but this can trigger seizure or arrhythmia.
Important valproate points
Used for all types
Less severe AE eg sedation, ataxia, tremor, weight gain, transaminase increase, nausea.
Inhibited by antiDs and antipsychotics.
Aspirin competes binding.
Monitor plasma level, blood, hepatic and metabolism disorders.
Phenytoin important points
Not used for LT control
Not usd for absence
IV acutely as therapeutic level reached fast
AE- gingival hyperplasia, ataxia, dizzy, headache, nystagmus, anxiety, hypersensitivity, tremor, dysarthria, decreased intellect, depression.
Non linear PK, very variable dose responses.
Monitor plasma level.
Compete for binding with valproate, NSAIDs.
OCP decrseas, cimetidine increases.
Lamotrigine important points
1st choice in adults NOT paeds as ADRs
Safer in pregnancy.
Used for all types
Less AE. Occasional rash and hypersensitivity, blurred vision, photosensitvity, tremor, vomiting, agitation, aplastic anaemia.
No CYP induction
Use with other AEDs
Valproate binding completion.
OTC decreases plasma level.
Carbamazepine important points
Not for absence
Contra indicated in AV conduction problems
AE include BP fluctuation, hypoNa, neutropenia, parasthesia, motor, blurred vision, diplopia, balance.
Induces own CYP metabolism.
Warfarin, phenytoin, OCP and systemic CS all decrease.
Monitor effect and adjust dose as levels fall.