Epilepsy Dr. Shreedhar Paudel May, 2009

Epilepsy… Recurrent, paroxysmal, involuntary clinical events associated with abnormal electrical activity from the neurons Abnormal motor, sensory and psychomotor phenomenon

Epilepsy… Causes of Epilepsy in Childhood – The etiologies vary in an age-dependent fashion – Neonates, infants, and toddlers → perinatal brain injury congenital central nervous system malformations metabolic derangements Poor myelination and incomplete dendritic arborization in neonates lead to clinical seizure characteristics different from that of older children

Epilepsy… Causes of Epilepsy in Childhood – Central nervous system infection, genetic epilepsies, and neurodegenerative disorders are more likely to present with seizures beginning in later childhood – These causes stand in contrast to the adult population, where traumatic brain injury, cerebrovascular disease, and neoplasms represent the most frequent causes of seizures

Epilepsy… Types:- – Generalised Tonic- clonic (grand mal) Tonic Clonic Absence (petit- mal) Atonic Epileptic myoclonus – Localised Simple complex

Epilepsy…. TONIC – CLONIC SEIZURES – Phases: 1. Aura 2.Tonic 3. Clonic 4. Postictal phase

Epilepsy… ABSENCE SEIZURES – Age 6-8 yrs – Absence moments – < 30 seconds – Inattentive pupils – Hyperventillation – precipitates – Pyknolepsy – EEG: 3 Hz spike and slow wave pattern

Epilepsy… MYOCLONIC SEIZURES West syndrome- triad of - Infantile spasm -Mental retardation -Hypsarrhythmic EEG ( diffuse high voltage slow spike and chaotic activity) Infants – 3-8 months Poor prognosis

Epilepsy… Management:- Under supervision of a physician for prolonged period extending over 1 to 4 years – Medical aspects – Emotional and psychosocial aspects (as chronic illness) – Identification of etiology – Side-effects of drugs

Epilepsy… Type of epilepsyDrugAlternative drugs Tonic- clonicCarbamazepinePhenobarbitone, Phenytoin Complex - partialCarbamazepine Absence seizuresEthosuximideSodium valproate, clonazepam Myoclonic seizures ACTHPrednisolone, sodium valproate

DrugsSide effects CarbamazepineRelatively safe, GI symptoms, hepatitis, skin rashes, BM depression PhenobarbitoneDrowsiness, dependency PhenytoinHirsuitism, gum hyperplasia, ataxia, diplopia EthosuximidePhotophobia, leukopenia, GI upset ACTHHypercorticism

Epilepsy…. Surgical treatment:- – Severely disabled cases – Resistant to medical treatment – Focal resection of parts of cerebral cortex (involved as epileptogenic foci)

Epilepsy Prognosis:- – % recurrence even after adequate course of anticonvulsants – Recurrence less if child is seizure free within 2 yrs of start of treatment – Relapse low in Generalised tonic- clonic Absence fits – Juvenile myoclonic Lifelong treatment

Epilepsy… Duration of therapy – Continued till 1-2 yrs in absence attacks and – 2 yrs seizure free period in tonic clonic seizures – Drug withdrawal should be attempted slowly over three months

Status epilepticus Single seizure or multiple episodes of seizures lasting more than 30 minutes without regaining consciousness in between In around 50% of cases SE is the first episode of seizure

Status epilepticus… Pathophysiology:- – Failure of mechanism that aborts the seizure Evaluation in ED:- – Good description of the event, surrounding circumstances, preliminary symptoms, progression of the clinical symptoms, duration of the event and postictal phase

Status epilepticus… Evaluation in ED:- – Presence of incontinence or tongue biting – hypoglycemia, CNS infections, CNS vascular events, drug toxicity, psychiatric disorders should be ruled out

Status epilepticus… Investigations:- – Serum glucose – Evaluation for underlying disorder if present – serum anticonvulsant level – patient with known seizure taking medications – CT, EEG

Status epilepticus… Management goals:- – Ensure adequate systemic and cerebral oxygen delivery – Terminate seizure activity – Prevent seizure recurrence – Diagnose and treat underlying cause if present

Status epilepticus… Management:- – Secure airway – Maintain oxygenation – Maintain blood pressure – Obtain IV access – Protect the patient from injury – If hypoglycemia suspected 25% dextrose given (2ml/kg) emperically

Status epilepticus… Management:- – Specific treatment Prehospital management of status epilepticus -A single dose of rectal diazepam by the caretakers -Usual rectal dose is mg/kg

Management of SE… Hospital treatment Diazepam IV or Lorazepam IV ↓ Repeat diazepam if seizure continues after 10 min ↓ IV Phenoitoin ↓ IV Phenobarbotal ↓ IM/PR Paraldehyde ↓ Midazolam infusion

Management of SE.. The benzodiazepine of choice is lorazepam for initial treatmentlorazepam – due to its long (2–8 hour) duration of action – rapid onset of action thought to be due to its high affinity for GABA receptors and to its low lipid solubility which causes it to remain in the vascular compartment.GABA receptorslipidsolubility vascular compartment – If lorazepam is not available, then diazepam should be given. [10] [10] – the failure of lorazepam alone is considered to be enough to classify a case of SE as refractory.refractory

Refractory SE The seizure that lasts for more than 60 min after initiation of treatment Seizure that continues even after 2 doses of Lorazepam Treatment is intubation and infusion of Midazolam or other forms of anaesthesia