Seizures

Prof.Dr.P.Soundararajan

seizure is a transient occurrence of signs and symptoms resulting from abnormal excessive or synchronous neuronal activity in the brain.

Febrile seizure; definition

• Between 6m to 60months• Fever >38oc • no CNS infection, no metabolic

imbalance• No prior febrile seizure

SFS

• GTC• <15mts• No >1 episode <24hrs• No postictal complications

CFS

• Focal• >1 episode in 24hrs• >15mts• Post ictal abnormality

• 2-5% incident• SFS; No risk of complications• CFS; 2 fold increase in morbidity

Cause

• Autosomal dominant• Many genes, • sodium channel genes

• generalized epilepsy with febrile seizures plus (GEFS+)

• severe myoclonic epilepsy of infancy

Recurrence

• <1yr age• <24hr of fever• Family h/o febrile fit or epilepsy• CFS• Male• Low serum sodium

RISK FACTOR RISK FOR SUBSEQUENT EPILEPSY

Simple febrile seizure 1%

Neurodevelopmental abnormalities 33%

Focal complex febrile seizure 29%

Family history of epilepsy 18%

Fever <1 hr before febrile seizure 11%

Complex febrile seizure, any type 6%

Recurrent febrile seizures 4%

Workup

• Thorough history & examination• LP [assess sensorium]• Prior antibiotics?

EEG

• Normal CNS; no need• Doesn’t predict epilepsy• Spikes seen during drowsy• To do >2 weeks• To know type of epilepsy• 30mts wakefulness & sleep

• Serum glucose• CT or MRI

– Status epilepticus [hippocampal atrophy]

Management • Counsel parent• Antipyretics • SFS; no drugs• CFS; Diazepam, lorazepam, midazolam• Rectal diazepam• Intranasal midazolam• Intermittent prophylaxis

– Diazepam, phenobarbitone, clobazam• Iron deficiency?

Status epilepticus

• continuous seizure activity or recurrent seizure activity without regaining of consciousness lasting for >30 min.

• impending status epilepticus ; seizures between 5 and 30 min.

• Nonconvulsive status epilepticus • Refractory status epilepticus

Causes

• 30% 1st episode SFS• CNS infection• Trauma• CVA• Metabolic imbalance• Poisoning

• Imbalance between excitation & inhibition• Increased excitability [glutamate, aspartate]

• Decreased GABA mediated inhibition• Inadequate O2 supply• Hypoxia• Cerebral edema• Ca influx into neurons• Neuronal death

Management

• A B C• Detect underlying etiology• Electrolytes, BUN, glucose• CSF study• EEG• Imaging

Drugs

• IV lorazepam• midazolam• Fosphenytoin• Phenobarbitone• Valproate• propofol, thiopentol• Isoflorane• Induced acidosis.

SE Protocol - 0 - 10 min

• Verify and describe seizure

• Airway - Positioning & suctioning

• O2 through mask, Attach pulse oxymeter

• NGT, BMV if needed

• Start IV / IO - IV lorazepam 0.1 mg / kg (1st dose)

• If no IV / IO, Midazolam IM 0.15 mg / kg

• Monitor HR, RR, perfusion, BP, SaO2

SE Protocol - 10 - 20 min

• Check Glucose - Dextrostix, IV dextrose

• Lab investigations

• IV lorazepam 0.1mg / kg (2nd dose)

• Monitor HR, RR, Perfusion, BP, SaO2

• BM ventilation if needed

• IV Phenytoin 20 mg / kg over 20 min. (1st dose)

• Fever reduction

SE Protocol - 40 - 50 min

• BM ventilation

• IV Phenytoin 10 mg / kg (2nd dose)

• If seizure still persists, IV Phenobarbitone

20mg / kg over 10 min.

• Intubate prior to Phenobarbitone

• Manage ICT

• Consider IV Pyridoxine if > 3 yrs old

SE Protocol - 60 min.Refractory Status Epilepticus

• Admit in PICU

• Involve Anesthetist / PICU team

• Support circulation

• Correct metabolic problems (Hypoglycemia,

Hypocalcemia, Hypomagnesemia)

• IV Midazolam infusion, Pentothal, IV Sodium

valproate

• IV Midazolam 0.15 mg / kg stat. dose

Maintenance - 1 mcg / kg / min.

• Raise / 1 mcg / kg / min. every 15 min. if seizure

persists. Maximum 20 mcg / kg / min.

• Higher the dose, need for ventilation

• After control, same rate of infusion for 24 hours

then taper by 1 mcg every 2 hours

Approach to seizure

• Assess CVS, RS status• Metabolic screen• Head examination• Eye ex• NCM• HSM• FND• EEG, imaging

Thank you