Epilepsy Flashcards
What is a seizure?
Paroxysmal
Synchronous
Uncontrolled
Excessive discharge of neurons
In cerebral cortex
Manifesting as a stereotyped disturbance of
- consciousness
- behavior
- emotion
- motor function
- sensation
What is epilepsy?
Recurrent
Unprovoked seizures
Occurring >24 hours apart
With a sudden onset, short duration and spontaneous cessation
Not associated with a precipitant
What is status epilepticus?
A medical emergency where
Continued
Or recurrent seizures
Over 30 minutes
Failure to regain consciousness between seizures
What is a prodrome?
Premonitory changes
In mood or behavior
Preceding a seizure
What is a an aura?
Subjective sensation or phenomenon
Preceding and marking onset of epileptic seizure
Localizes the seizure origin
What is the post ictal period?
Time after the seizure
Drowsy
Confused
Disorientated
Residual focal neurological signs
What is the classification of seizures?
PARTIAL/ FOCAL seizures
SIMPLE (no LOC) -seconds-
With motor
With sensory
With autonomic
With psychological (deja vu)
COMPLEX (LOC) -minutes-
Simple + loc
PARTIAL WITH SECONDARY
GENERALIZATION
GENERALIZED seizures
ABSENCE
typical (petit mal)
Atypical
OTHER
GTCS (grand mal)
Tonic
Clonic
Myoclonic
Atonic
What are the aetiologies of epilepsy?
PRIMARY - no cause identifiable
(2/3rds)
SECONDARY
Vascular Cerebrovascular disease👈 Venous sinus thrombosis Arteritis AVM
Infectious Encephalitis Meningitis Cerebral abscess Neurosyohillis
Neoplastic 👈 Intracranial tumors (specially new onset adult)
Degenrative Dementias
Congenital IU infections (tox, rub) Maternal drug abuse Irradiation Perinatal trauma and anoxia
Trauma / toxic Head injury👈 Brain surgery Chronic alcohol abuse👈 Carbon monoxide Phenothiazines MAO inhibitors TCAD Amphetamines Lidocaine Nalidixic acid Sudden withdrawal of anticonvulsants
Endocrine/ metabolic Hyponatremia Hypernatremia Hypocalcemia Hypomangesemia Hypoglycemia Uremia Hepatic Hypoxia Porphyria
Photosensitivity
Sleep deprivation
What are the diagnostic criteria for epilepsy?
At least 2 unprovoked seizures occurring >24 hours apart
One unprovoked seizure and a probability of further seizures risk of 60% over next 10 years
Diagnosis of an epilepsy syndrome
What are the sites of origin of focal epilepsies by frequency?
Temporal 60%
- early adult/ adolescents
- hippocampus damage
- Dysembryoblastic NET
Frontal
Parietal
Occipital
What are automatisms?
Involuntary
Complex
Motor activity
Which occur PRE, INTRA or POST ictal
What are the features of temporal lobe seizures?
Complex aura \+ Subtle clouding of consciousness \+ Lasting few seconds \+ Post ictal confusion and headache Can generalize
COMPLEX AURA
Visceral disturbances Epigastric fullness Olfactory or gustatory hallucinations Lip smacking Choking sensation Nausea Pallor Mydriasis Tachycardia
Memory disturbances Deja vu Jamais vu Flashbacks Depersonalization Derealization Visual or auditory hallucinations
Motor disturbances Fumbling Rubbing Chewing Walking
Affective disturbances Displeasure Pleasure Depression Elation Fear
What are the features of frontal lobe seizures?
Abrupt onset
Indescribable aura
Automatisms, stereotyped movements
Head and eye versions to contralateral side
Fencing posture
Lasts seconds
Post ictal rapid recovery
What is a Jacksonian seizure?
Motor cortex
Matching pattern from face/ hands
Clonic or tonic
Todd’s paralysis for few hours
What are the features of parietal lobe seizures?
Somatosensory symptoms
-paresthesia, tingling, pain
Distortion of space and body image
Motor involvement
What are the features of GTCS?
Sudden LOC, no aura
Fall to the ground
Tonic phase lasting 10 seconds
-open eyes, flexed elbows, pronated arms,
Legs extended, clenched teeth, dilated pupils, cyanotic, ending with incontinence
Clonic phase lasting 1 to 2 minutes
-violent generalized shaking, eyes roll back
Bitten tongue, tachycardia
Post ictal sleep, confusion and headache, drowsiness
What are the features of absence seizures?
Children with inattentiveness and poor grades
Several times a day
Lasting seconds
Triggered by hyperventilating
Sudden vacant stare
Blinking and myoclonic jerks
Characteristic 3 Hz EEG generalized spike and wave pattern
What are the causes of neonatal seizures?
Asphyxia ICH Hypocalcemia Hypoglycemia Hyperbilirubinemia Over hydration Inborn errors of metabolism
What are the causes of infant and childhood seizures
Febrile convulsions CNS Infection Trauma Congenital defects Inborn error of metabolism Tumors
What are the DDx for seizures?
Syncope
Arrhythmia
Hypoglycemia
Episodic confusion
Panic attacks
Narcolepsy
What are the idiopathic epilepsy syndromes?
West syndrome
Lennox Gastaut syndrome
Childhood absence epilepsy
Juvenile myoclonic epilepsy
How is epilepsy investigated?
Corroborate the diagnosis
Classify the epilepsy
Find an aetiology
Eliminate DDxs
INVESTIGATIONS
Imaging MRI > CT
EEG + videotelemetry
Blood tests - ABG, CPK, PRL,
What is status epilepticus?
Successive
Tonic clonic seizures
With a gap inbetween
Where consciousness does not return
Lasting for more than 5 minutes (30 mins)
Life threatening
What are the risk factors for status epilepticus?
Frontal lobe lesions
Head injury
Drug withdrawal (phenobarbitone)
Alcohol
Drug intoxication (TCAD)
Infections
Hyponatremia
Pregnancy
How is status epilepticus managed?
Premonitory stage (0-10 mins)
ABC Establish airway, high flow O2 Normal saline infusion Do ABG, CBS, SE, RFT, LFT Treat causes Treat complications
Diazepam 10-20mg sup
Midazolam 10 mg buccal
Repeat in 10-20 mins if necessary
Early status (10-30 mins)
Lorazepam 4 mg iv
Can repeat but beware respiratory loss
Established status (30-60 mins)
Phenytoin 15-18 mg/kg
Fosphenytoin 15-20 mg/kg iv
50 mg/ min and monitor heart
Refractory status (after 60 mins) GA with propofol 2 mg/kg bolus then 5-10 mg/kg/h infusion
How is epilepsy managed?
Medical
Anticonvulsant monotherapy if high risk of recurrence
1st line Carbamazepine Sodium valproate Lamotrigine Phenytoin
2nd line Clobazam Clonazepam Gabapentin Topiramate Levetiracetam Pregabalin Zonisamide Lacosamide Rufinamide Retigabine Oxcarbazepine Phenobarbital
Surgical
What are febrile seizures?
Seizures in the presence of fever which can’t even prevented by antipyretics
Most common cause of seizure in 6 month to 6 year age group
Not common in children (4%)
Typical / simple febrile seizures are generalized, last <15 mins and occur only once in a 24 hour period in a neurologically and developmentally normal child
Excellent prognosis, normal intellect, can recur
Risk of epilepsy is same as other children
Atypical febrile seizures are focal, last longer than 15 mins, recur within 24 hours in a child with preexisting neurological challenges
