Seizure disorders in children for Undergraduates- Dr. D. Gunasekaran - Pediatrics

Seizure disorders in children

Dr. D. GunasekaranConsultant Paediatrician

To enable you :

To identify the seizure

To identify the probable type

To initiate managing a child with seizure

To identify and manage Febrile seizures

To understand the stepwise management of status epilepticus and its significance

Define: Seizures / Convulsions / Fits:

Sudden, excessive discharge of neurons resulting in involuntary motor, sensory or autonomic disturbances

with or without alteration in sensorium

USA statistics: 5% of children are at risk of getting at least once in a life time

Focal: Neurons in one hemisphere.(conscious +): Focal insult (tumour)

Generalized: Neurons of both hemispheres (conscious is lost) (Generalized insult to both hemispheres – hypoxia)

Febrile seizures: Seizures due to fever of extra-cranial origin

Acute symptomatic seizures: secondary to an acute problem (Electrolyte, Glucose, Encephalitis & Meningitis), usually GTC

Unprovoked seizures: No obvious reason

Epilepsy: >2 unprovoked seizures, >24 hours apart

Epileptic syndrome: 1 or more specific seizure types, specific age of onset & specific prognosis.

Idiopathic epilepsy: No underlying disorder; presumably genetic

Symptomatic epilepsy: Underlying brain disorder (epilepsy secondary to Tuberous sclerosis)

Cryptogenic epilepsy (presumed symptomatic epilepsy): Presumed underlying brain disorder but the cause is not known

Epileptic encephalopathy: Severe EEG abnormality, Cognitive impairment

Excitatory Amino acid

Injury to Neurons

Death of neurons

Excessive discharge concerned activity

Motor cortex jerking of limbs

Do you know the most common investigation used to diagnose seizures?

Electrodes

Electrical activity of brain

Waveforms: theta, delta, alpha and beta

Abnormalities of wave form: spike & slow waves

Epileptiform activity may be enhanced by activation procedures:hyperventilation, photic stimulation & sleep deprivation

Use: to diagnose seizures; to classify seizures

FOCAL

CONSCIOUSNESS IS MAINTAINED

a. Focal seizures with retained consciousness (Simple partial)

b. Focal dyscongnitive (Complex partial)

c. Partial seizures with secondary generalization

GENERALIZED

CONSCIOUSNESS IS IMPAIRED

a. Petit mal (Absence)

b. Grandmal

c. Myolconic

Rare & complex seizure types and syndromes are not included in this classification

Aura: Sensory experiences (depend on the location)

Visual (flashing lights/seeing colours)

Somato-sensory (tingling)

Olfactory, auditory, vestibular

Experiential (dejavu)

Post-ictal period:

Sleep, vomit, automatism

1. Simple Partial (Focal S with retained consciousness):

Motor: tonic/ clonic – particular limb

Sensory: abnormal sensation of a particular limb or part of limb

Autonomic: excessive sweating, palpitation

Versive: head turning & conjugate deviation of eyes

May verbalize during the seizures - 10-20 sec only

No post-ictal phenomenon

EEG: spikes or sharp waves

2. Focal dysconjugative seizures (Complex Partial) :

1/3 has Aura: Epigastric discomfort, fear

Act: brief blank stare or sudden cessation of activity; lasts for 1-2 m min.

2/ 3 has Automatism: usually, alimentary; lip smacking, repeated chewing , repeated swallowing; pulling at clothes, walking & running aimlessly

EEG: sharp waves or focal spikes and multi focal spikes

MRI: may show abnormalities over temporal regions

3. Focal Generalized seizures

1. Petit mal or Typical Absence seizures:- (5-8 years)

Aura: Absent

Breathing: Hyperventilation for 3 min, could ppte. a seizure.

Seconds – each seizure lasts for seconds, but can have 100 such seizures in a day.

Eye lid flutter with brief blank stare or sudden cessation of activity, or upward rolling of eyes

No florid automatisms (if at all, simple automatisms like lip smacking)

Three Hz spike – slow – wave discharges – Typical in EEG

2. Grandmal seizures:-

Prodromal: hours to days- irritability; uneasiness

Aura: Minutes to seconds- Epigastric discomfort, fear

Tonic: 10-30 sec- Resp. muscle spasm: cry as the air is expelled –cyanosis may be +; consciousness is lost

Clonic: 1-5 min- jerking of all 4 limbs & face; may bite teeth; urine & fecal incontinence can occur

Post-ictal state: 30 min -2 hours: semicoma to deep sleep; may have headache / vomiting.

2. Grandmal seizures:

Age: 9-25 years

Usually within 2 hours after sleep.

Photic stimulation, sleeplessness & hypoglycemia can precipitate.

EEG: 2.5 to 4 Hz spike and wave activity enhanced by hyperventilation & photic stimulation

3. Myoclonic seizures:-

Brief, symmetric muscular contractions ( 1-2 seconds)

Loss of body tone –fall forward -cause injuries to the face and the mouth (if he is standing)

Several types

Prognosis may vary - very good to very bad.

Benign: Benign childhood epilepsy with centrotemporal spikesBenign epilepsy with occipital spikes

Serious: Temporal lobe epilepsy Landau-Kleffner epileptic aphasia syndromeRasmussen encephalitis (chronic encephalitis-intractable epilepsy

–progressive atrophy of cerebral hemisphere)

Type of myoclonic

epilepsies

Age Symptomatic/

Idiopathic

EEG Prognosis Drug

Early myoclonic

encephalopathy

Neona

te

Severe

Neurological

abnormalities

Suppression alternating

complex bursts of spike,

sharp & slow wave

Very poor;

early death

West syndrome

(Infantile

spasms) Flexor /

Extensor/ Mixed

3-8

mon

MR +;

70% HIE, NTD;

CNS infn.

30% crypto

Hypsarrythmia (high

voltage, slow, chaotic

background with

multifocal spikes)

Very poor;

5% may recover

Valproate,

ACTH,

Benzodiazepines

Vigabatrin

Benign

myoclonic

epilepsy of

infants

1-2yrs Normal .Normal Very good; stops

by 2 years of

age

No drug

Lennox-gestaut

syndrome triad:

developmental

delay, multiple

seizure types,

EEG)

3-5yrs MR,

Neurologically

abnormal:90%

Diffuse slow spike &

wave

Very poor; often

status epi for

days

Resistant to

many drugs.

ACTH tried.

Myoclonic

astatic

3-5yrs Normal in the

beginning

Irregular spike & wave

in sleep

50% better

Juvenile

myoclonic

epilepsy of Janz

(Janz syndrome)

8-

26yrs

Normal 4-6 Hz polyspike & slow

wave gen discharges

Better with drug Valproate

Life long

Landau Kleffner: Acquired aphasia with epilepsy syndrome

Aphasia +

Behavioural problems are common

Seizures: partial or generalized

EEG:

Prognosis: long term recovery of language function is not very good

Treatment: Valproic acid is the drug of choice

Duration, type of movements, aura, automatism, frequency

Associated illness: fever, loose stools, …

Sometimes, parents may overlook: absence, CPS

Precipitating events: less sleep, stress, television, menstruation

H/O Prenatal or perinatal insult

H/O Regression of mile stones

H/O Personality changes / ICT: Brain tumour

If the child is convulsing in front of you..

Inititial steps:

Shift child to a safer place (away from water, fire..)

Put him in left lateral position (to prevent aspiration, if V)

Roll a kerchief and keep between teeth, if possible

ABC

Airway: clear the secretions

Breathing: give O2 / bag and mask / intubation

Circulation: Pulse/ BP/ CFT: IVF

Emergency therapy: Stop the convulsions with fast acting Benzodiazepines..

Diazepam / Lorazepam/ Midazolam: Lora: Longer duration of action; (0.05 mg/kg)Midazolam: by any route: IM/Nasal/Buccal (0.1mg/kg)

Even 5 minutes after the 1st dose of Benzodiazepines, if convulsions do not stop:

Give 2nd dose of Benzodiazepines + Start long acting drugs IV (Phenytoin/PB)

At 10 min: 3rd dose of BenzodiazepinesAt 15 min: 4th dose of Benzodiazepines

Then plan Investigations

Blood sugar Serum electrolytes Serum calcium Smear for malaria CSF analysis CT scan / MRI EEG

If it is a symptomatic seizure, usually they may not require long term anticonvulsants.

Otherwise, give daily anticonvulsants until 2 years of seizure free interval

Anti- convulsants: which one to choose?

It depends on the type of the seizure

Age of the child (Valproate is avoided in < 2 yrs)

Sex of the child (Phenytoin avoided inadolescent females)

Pre-existing disease if any. (Jaundice)

Seizure types Drug of choice

Focal Carbamazepine

GTC Valproate / Phenytoin / Phenobarbitone

Absence Valproate / Ethosuximide

Myoclonic Valproate / clonazepam / clobazam

Drugs Not serious but common Serious

Phenytoin Gingival hyperplasia,

hirsuitism, ataxia

Stevens –Johnson syndrome

Liver damage

Phenobarb

itone

Disturbances is memory,

mood & sleep

Same as above

Carbamaz

epine

Weight gain, Nausea Stevens Johnson syndrome

Liver damage

Aplastic anemia

Valproic

acid

Weight gain, Menstrual

irregularities, alopecia

Liver damage

Pancreas damage

Benzodiaz

epines

Sedation Respiratory depression

In emergencies: loading dose: PB / PH: 20 mg

In non emergencies: maintenance dose is started

Small dose gradually increased (carbamazepine)

Steady blood level after 5 half-lifes (2-7 days) (PB: 2-4 wks)

Monotherapy-max. dose-start another-taper the first one

Monitored for side effects (Vit D: PB, Phenytoin; PH: good oral hygiene; rinsing the mouth after phenytoin)

Stopping: if child is seizure free > 2 years; gradually, even over 3 months

Defn: “Seizures due to fever of extra-cranial origin”

Neurologically normal children

Prevalence: 3-4% in the community

Risk is more, if parents / siblings have FS (10-45%)

Genetical predisposition: Chromosomes 19, 9 & 5

Patho-physiology:

Rise in temp rise in excitatory postsynaptic potential convulsion

Rise in temp failure of Na-K pump at cellular level convulsion

Age: 6 months to 60 months

Within 24 hours of onset of fever

Usually occurs once only for one episode of fever

Lasts < 15 minutes; GTC in type

After 24 hours: No focal deficit

EEG: 2 wks after seizure (sleep & awake 20 min): normal

Those who do not satisfy any of the above criteria, ATYPICAL

Chance of relapse: 25-30% with every episode of fever

Recurrence risk is more:

First episode of seizures < 1 year

Family H/o Febrile seizures / epilepsy

Atypical febrile seizures

Risk of epilepsy:

Complex FS / Neuro developmental abnormalities

Risk of developing Status epilepticus: 5%

If child already had status, the risk of getting another status is more

1) Control of temp (Para & tepid sponging)

2) Intermittent Prophylaxis: Diazepam / Clobazam – 48 hours

3) Treat the cause for fever

4) If the child is throwing the seizures: ----

Definition:

Single or Multiple episodes of seizures, without regaining consciousness lasting for > 30 min; mostly generalized / can be partial

To be more practical:

Any child convulsing for > 5 min, should be considered as status (because, all self limited seizures usually stop in < 5 minutes)

Any child presenting to the casualty with active seizures should be considered as status only.

Why it is important?

Risk of cerebral edema, hypoxia, hyperthermia, hypoglycemia, vasomotor in-stability, vomiting & aspiration and respiratory depression

Risk of death / residual neurological sequelae

1/3: first seizure itself will present with status

1/3: occur in already diagnosed epilepsy patients

1/3: occur due to some acute insult

In India, the most common cause is febrile seizures

0 min: ABC; send blood for investigations (Blood glucose, serum electrolytes, BUN, Toxicology screen & serum anticonvulsants

levels)Give one dose of Benzodiazepine(Lora 0.1mg/kg; Mid 0.15mg/kg; Dia 0.3mg/kg)

+ Phenytoin : 20mg/kg @ 1mg/kg/min+ if CBG less, give dextrose 4 ml/kg

At 5 min: if seizures + : repeat BenzoAt 10 min: if seizures +: repeat BenoAt 15 min: if seizures + : repeat Benzo

At 20 min: if seizures + : (Refractory Status)add PB 5-10mg/kg @

1mg/kg/minrepeat

At 40 min: if seizures+ : midazolam infusion: 2-10mcg/kg/min consider sodium valproate infusion / ventilator support

Physical and neurological examination:LP & Antibiotics if meningitis suspected

Trauma with intracranial bleed:CT & Neuro surgeon’s opinion

Serum anti-convulsants levels

Mortality rate is 5%

Morbidity (Neurologic sequelae) common < 1 yrs

Thank you