seizures in childhood kitesh moodley january 2009

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Seizures in Childhood Kitesh Moodley January 2009

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Page 1: Seizures in Childhood Kitesh Moodley January 2009

Seizures in Childhood

Kitesh Moodley

January 2009

Page 2: Seizures in Childhood Kitesh Moodley January 2009

Introduction• Convulsion associated with febrile disease

– 2-4% of all children before the age of 5 years

• Symptomatic seizures– 0.5-1%

• Epilepsy:– Recurrent unprovoked seizures

• First year of life:– 1,2/1 000

• Childhood and adolescents:– 0,5-1/10000

Page 3: Seizures in Childhood Kitesh Moodley January 2009

Aetiology of Epilepsy

• Specific aetiology– Identifiable in only

30% of cases

• Idiopathic 67.6%• Congenital 20%

– Trauma– HIE– Congenital brain

anomalies

• Trauma4.7%

• Infection4.0%

• Vascular1.5%

• Neoplastic 1.5%

Page 4: Seizures in Childhood Kitesh Moodley January 2009

Seizure type

Partial (Only a portionof the brain)

- Simple(Normal consciousness)- Complex(Impaired consciousness)

Generalized(Both hemispheres areinvolved)

Page 5: Seizures in Childhood Kitesh Moodley January 2009

Epilepsy classification• Clinical presentation is quite variable

– age of onset– seizure type– interictal condition– EEG– Outcome

• Evaluate the: – the epileptic syndrome– Possible aetiology

• The seizure type and syndrome type determine the– Specific appropriate treatment– Further evaluation

Page 6: Seizures in Childhood Kitesh Moodley January 2009

ILAE.org

1. Partial seizures– Simple

• With motor symptoms• Autonomic symptoms• Psychic symptoms

– Complex• Simple then altered LOC• Altered LOC from beginning

– Simple or complex which become generalised

Page 7: Seizures in Childhood Kitesh Moodley January 2009

• Generalised Seizures– Absence– Myoclonic– Clonic– Tonic– Atonic– Tonic-clonic

Page 8: Seizures in Childhood Kitesh Moodley January 2009

Epilepsy syndromes

• Seizures may occur as partial or generalised

• Further divided into – Idiopathic– Symptomatic– Cryptogenic

• Special situations i.e febrile seizures

Page 9: Seizures in Childhood Kitesh Moodley January 2009

Main Periods according to Age

• Neonates– Subtle, erratic, non-febrile

• Infancy and early childhood– 3 months to 3 years– Febrile seizures– Infantile spasms– Lennox Gastaut– Myoclonic seizures– Status epilepticus– Partial complex

Page 10: Seizures in Childhood Kitesh Moodley January 2009

Main Periods according to Age

• Childhood to early adolescence– Cryptogenic– Absences– Benign rolandic epilepsy

• Nine years to adulthood– Primary generalized epilepsy– Focal epilepsy with brain injury

Page 11: Seizures in Childhood Kitesh Moodley January 2009

Stats from ILAE

• Primary tonic-clonic seizures 20%

• Simple partial 20%

• Absence seizures 10% (more in children)

• Other 10%

• 40% of Epilepsy in adults is Complex partial seizures

Page 12: Seizures in Childhood Kitesh Moodley January 2009

Neonatal seizures• Subtle seizures

– Deviation of the eyes

– Eyelids are flickering

– Swimming or pedaling movements

– Apnoeic spells

• Tonic

• Clonic

• Myoclonic

• Seldom tonic clonic seizures

Page 13: Seizures in Childhood Kitesh Moodley January 2009

Aetiology of neonatal seizures

• Perinatal:– HIE

• Metabolic– Hypoglycemia,

hypocalcemia– hypomagnesemia– Other

• Infections• Structural

abnormalities

Page 14: Seizures in Childhood Kitesh Moodley January 2009

Treatment of neonatal seizures

• Optimize ventilation, cardiac output, BP, glucose, electrolytes and pH.

• Treat the underlying disease

• Intravenous line is essential

• Treat the seizures promptly and vigorously

• Phenobarbitone

• Phenytoin

Page 15: Seizures in Childhood Kitesh Moodley January 2009

Febrile seizures

• Definition:– Seizure in children between the age of 6

months and 3-4(5) years in association with fever but without evidence of an intracranial infection

• Majority occurs before the age of 3 years

• Average age of onset: 18 months to 22 months

• Boys more than girls

Page 16: Seizures in Childhood Kitesh Moodley January 2009

Pathophysiology

• Seizure threshold is low in children

• Susceptible to infections i.e urti, LRTI

• Possible role of endogenous pyrogens IL1– May increase neuronal activity

• Probable role of cytokines

Page 17: Seizures in Childhood Kitesh Moodley January 2009

2 Types

• Simple febrile seizures– Generalise– <15min duration– Do not recur within 24hrs

• Complex– Prolonged seizures– Usually more than one in a 24hr period– Or may be focal– Indicative of a more serious condition

Page 18: Seizures in Childhood Kitesh Moodley January 2009

Febrile seizures• Recurrence

– 1/3 may have at least one recurrence– The younger the age of onset the greater the risk of

recurrence– Low fever at first seizure– Family hx

• Risk of developing epilepsy– 2% (vs 1% in gen pop)– Risk increases with:

• Complex• Abnormal neurological state

Page 19: Seizures in Childhood Kitesh Moodley January 2009

Investigation of febrile seizures

• Lab investigations, although routine, usually unhelpful, in the evaluation of first time seizure – possible just a Na and Glucose

• CT is not warranted in the evaluation of simple febrile convulsions but considered for complex – Study of 71 patient with complex seizures

• None had an intracranial condition requiring treatement

• Routine EEG is seldom necessary

• ??LP– Simple febrile seizure probable not indicated

• Probable those with prolonged post-ictal phase

– Current recommendation should be routine in the under 12 month group

Page 20: Seizures in Childhood Kitesh Moodley January 2009

Treatment of febrile convulsion

• Oxygen and supportive care

• Benzodiazapines

• Antipyretics– Do not appear to prvent recurrence

• Councel parents

Page 21: Seizures in Childhood Kitesh Moodley January 2009

Treatment of Epilepsy

– Drug treatment should be regular– Simple as possible– Minimum of side effects– Monotherapy– Changes should be made gradually– High initial dosages increases side effects– Rapid withdrawal carries the risk of provoking status– Always calculate the dosage according to the

weight

Page 22: Seizures in Childhood Kitesh Moodley January 2009

Treatment of Epilepsy• Drugs commonly used

– Carbamazepine

– Sodium valproate

– Clonazepam

– Phenobarbitone

– Phenytoin

• Newer drugs

– Clobazam

– Oxcarbazepine

– Gabapentin

– Vigabatrin

– Lamotrigine

Page 23: Seizures in Childhood Kitesh Moodley January 2009

Treatment of Epilepsy

• Antiepileptics can cause convulsions– Benzodiazepines can induce TC seizures in LGS– Carbamazepine may exacerbate absence

seizures

• What is used as first line treatment.– Absence:

• Sodium valproate

– Focal and Generalized TC:• Carbamazepine

Page 24: Seizures in Childhood Kitesh Moodley January 2009

• Status epilepticus (SE) presents in a multitude of forms, dependent on aetiology and patient age (myoclonic, tonic, subtle, tonic-clonic, absence, complex partial etc.)

• Generalized, tonic-clonic SE (GCSE) is the most common form of SE

Page 25: Seizures in Childhood Kitesh Moodley January 2009

Definition

• Conventional “textbook” definition of status epilepticus:

– Single seizure > 30 minutes

– Series of seizures > 30 minutes without full recovery

Page 26: Seizures in Childhood Kitesh Moodley January 2009

Why 30 minutes ?

Animal experiments in the 1970s and 1980s had shown that ...

… neuronal injury could be demonstrated after 30 min of seizure activity, even while maintaining respiration and circulation

Nevander G. Ann Neurol 1985;18(3):281-90.

Page 27: Seizures in Childhood Kitesh Moodley January 2009

More practical: Mechanistic definition

• GCSE is a condition which most likely will not terminate rapidly and / or spontaneously

• GCSE is a condition which requires prompt intervention

Lowenstein DH. Epilepsia 1999

Page 28: Seizures in Childhood Kitesh Moodley January 2009

The longer SE persists,

–the lower is the likelihood of spontaneous cessation–the harder it is to control–the higher is the risk of morbidity and mortality

Bleck TP. Epilepsia 1999;40(1):S64-6

The Status Epilepticus Working Party. Arch Dis Child 2000;83(5):415-9.

Page 29: Seizures in Childhood Kitesh Moodley January 2009

Typical seizure duration

• Children > 5 years:

Typical, generalized tonic-clonic seizure lasts < 5 minutes

• Young children and infants:

little data. latsts < 10-15 minutes

Reviewed in: Lowenstein DH. It's time to revise the definition of status epilepticus. Epilepsia 1999;40(1):120-2.

Page 30: Seizures in Childhood Kitesh Moodley January 2009

Revised Definition

• Generalized, convulsive status epilepticus in older children (> 5 years) refers to > 5 minutes of continuous seizure or >2 discrete seizures with incomplete recovery of consciousness

Page 31: Seizures in Childhood Kitesh Moodley January 2009

Causes

• Fever• Medication change• Unknown• Metabolic• Congenital• Anoxic• Other (trauma, vascular,

infection, tumor, drugs)

36%

20%

9%

8%

7%

5%

15%

\\

Page 32: Seizures in Childhood Kitesh Moodley January 2009

Mortality

• Adults• Children

15 to 22%

3 to 15%

Reviewed in: Fountain NB. Epilepsia 2000;41 Suppl 2:S23-30Reviewed in: Fountain NB. Epilepsia 2000;41 Suppl 2:S23-30

Page 33: Seizures in Childhood Kitesh Moodley January 2009

Mortality

• The primary determinant of mortality and morbidity of SE in children is its aetiology

• With the highest mortality rates caused by an acute neurological condition (infection, trauma, stroke)

Mitchell WG. J Child Neurol 2002;17 Suppl 1:S36-43.Mitchell WG. J Child Neurol 2002;17 Suppl 1:S36-43.

Page 34: Seizures in Childhood Kitesh Moodley January 2009

Prolonged seizures

Duration of seizureDuration of seizure

Life Life threateningthreatening

systemicsystemicchangeschanges

DeathDeathTemporaryTemporary

systemicsystemicchangeschanges

Page 35: Seizures in Childhood Kitesh Moodley January 2009

Respiratory• Hypoxia and hypercarbia

– Ventilation • (chest rigidity from muscle spasm)

– Hypermetabolism • ( O2 consumption, CO2

production)

– Poor handling of secretions– Neurogenic pulmonary oedema

Page 36: Seizures in Childhood Kitesh Moodley January 2009

Hypoxia

• Hypoxia/anoxia markedly increase (triple?) the risk of mortality in SE

• Seizures (without hypoxia) are much less dangerous than seizures and hypoxia

Towne AR. Epilepsia 1994;35(1):27-34

Page 37: Seizures in Childhood Kitesh Moodley January 2009

Acidosis

• Respiratory

• Lactic– Impaired tissue oxygenation– Increased energy

expenditure

Page 38: Seizures in Childhood Kitesh Moodley January 2009

Haemodynamics

• Sympathetic overdrive – Massive catecholamine /

autonomic discharge– Hypertension– Tachycardia

• Exhaustion– Hypotension– Hypoperfusion

• Exhaustion– Hypotension– Hypoperfusion

0 min0 min 60 min60 min

Page 39: Seizures in Childhood Kitesh Moodley January 2009

Cerebral blood flow - Cerebral O2 requirement

Blood pressureBlood pressure

Blood flowBlood flow

OO22 requirement requirement

Seizure duration

Hyperdynamic

Exhaustion

Lothman E. Neurology 1990;40(5 Suppl Lothman E. Neurology 1990;40(5 Suppl 2):13-23.2):13-23.

• Hyperdynamic phase – CBF meets CMRO2

• Exhaustion phase– CBF drops as

hypotension sets in– Autoregulation

exhausted– Neuronal damage

ensues

• Hyperdynamic phase – CBF meets CMRO2

• Exhaustion phase– CBF drops as

hypotension sets in– Autoregulation

exhausted– Neuronal damage

ensues

Page 40: Seizures in Childhood Kitesh Moodley January 2009

GlucoseG

luco

se

Seizure duration

30 min

SESE

SE + hypoxiaSE + hypoxia

Lothman E. Neurology 1990;40(5 Suppl 2):13-23.Lothman E. Neurology 1990;40(5 Suppl 2):13-23.

• Hyperdynamic phase – Hyperglycemia

• Exhaustion phase– Hypoglycemia

develops– Hypoglycemia

appears earlier in presence of hypoxia

– Neuronal damage ensues

• Hyperdynamic phase – Hyperglycemia

• Exhaustion phase– Hypoglycemia

develops– Hypoglycemia

appears earlier in presence of hypoxia

– Neuronal damage ensues

Page 41: Seizures in Childhood Kitesh Moodley January 2009

Hyperpyrexia

• Hyperpyrexia may develop during protracted SE which impairs substrate delivery while increasing metabolic demand

• Treat hyperpyrexia aggressively– Antipyretics, external cooling

– Ensure normal temperatures

Page 42: Seizures in Childhood Kitesh Moodley January 2009

Other alterations

• Increase WCC (50% of children)

• Spinal fluid leukocytosis (15% of children)

• K+

• creatine kinase

• Myoglobinuria

Page 43: Seizures in Childhood Kitesh Moodley January 2009

Oxygen, oral airway. Suction. Avoid hypoxia!

Consider bag-valve mask ventilation. Consider intubation

IV/IO access. Treat hypotension, but NOT hypertension

AA

BB

CC

Page 44: Seizures in Childhood Kitesh Moodley January 2009

Treatment

Intubate?– It may be difficult to intubate a child with active

seizures

– Stop or slow seizures first, give O2, consider BVM ventilation

– If using paralytic agent to intubate, assume that SE continues

Page 45: Seizures in Childhood Kitesh Moodley January 2009

Initial investigations

• Labs– Na, Ca, Mg, PO4 , glucose

– WCC– Liver function tests,

ammonia– Anticonvulsant drug level– Toxicology

Page 46: Seizures in Childhood Kitesh Moodley January 2009

Initial investigations

• Lumbar puncture– Always defer LP in unstable patients, but never

delay antibiotic/antiviral treatment if indicated

• CT scan– Indicated for focal seizures or focal deficit or

focal EEG, history of trauma or bleeding disorder

Treatment of convulsive status epilepticus. Recommendations of the Epilepsy Treatment of convulsive status epilepticus. Recommendations of the Epilepsy Foundation of America's Working Group on Status Epilepticus. JAMA 1993;270(7):854-Foundation of America's Working Group on Status Epilepticus. JAMA 1993;270(7):854-9.9.

Page 47: Seizures in Childhood Kitesh Moodley January 2009

Treatment

• Give glucose (2-4 ml/kg D25%, infants 5 ml/kg D10%), unless normo- or hyperglycemic

• Hyperglycemia has no negative effect in SE

Page 48: Seizures in Childhood Kitesh Moodley January 2009

Treatment

• The longer you wait to administer anticonvulsants, the more anticonvulsants you will need to stop SE

• Most common mistake is ineffective dose

Page 49: Seizures in Childhood Kitesh Moodley January 2009

Anticonvulsants

• Rapid acting

plus

• Long acting

Page 50: Seizures in Childhood Kitesh Moodley January 2009

Anticonvulsants - Rapid acting

• Benzodiazepines– Lorazepam 0.1 mg/kg i.v. over 1-2

minutes– Diazepam 0.2 mg/kg i.v. over 1-2

minutes

– If SE persists, repeat every 5-10 minutes

Page 51: Seizures in Childhood Kitesh Moodley January 2009

Benzodiazepines

• Diazepam– High lipid solubility– Thus very rapid onset – Redistributes rapidly– Thus rapid loss of

anticonvulsant effect– Adverse effects are

persistent:• Hypotension• Respiratory depression

• Lorazepam– Low lipid solubility– Action delayed 2 minutes– Anticonvulsant effect 6-12

hrs– Less respiratory

depression than diazepam

• Midazolam– May be given i.m.

Page 52: Seizures in Childhood Kitesh Moodley January 2009

Benzodiazepine - Intramuscular

• Intramuscular midazolam– 0.2 mg/kg i.m. – Aqueous solution is rapidly absorbed,

anticonvulsant effect begins after 2 minutes

• Intramuscular lorazepam– Can be given, but lacks water solubility, thus

later onset than midazolam

Chamberlain JM. Pediatr Emerg Care 1997;13(2):92-4.

Towne AR. J Emerg Med 1999;17(2):323-8.

Page 53: Seizures in Childhood Kitesh Moodley January 2009

Anticonvulsants - Long acting

• Phenytoin– 20 mg/kg i.v. over 20 min

– pH 12

Extravasation causes severe tissue injury– Onset 10-30 min– May cause hypotension, dysrhythmia

Page 54: Seizures in Childhood Kitesh Moodley January 2009

Anticonvulsants - Long acting

• Phenobarbital– 20 mg/kg i.v. over 10 - 15 min– Onset 15-30 min– May cause hypotension, respiratory

depression– Neurology RXH : no upper limit to phenobarb

• High dose phenobarb for SE will prob need icu admission

Page 55: Seizures in Childhood Kitesh Moodley January 2009

If SE persists

• Propofol infusion 5-10 mg/kg/hr after bolus 2 mg/kg

• Midazolam infusion 1 - 10 mcg/kg/min after bolus 0.15 mg/kg

• Isoflurane

Page 56: Seizures in Childhood Kitesh Moodley January 2009

Non - convulsive status epilepticus

• How do you tell that patient’s seizures have stopped?

Page 57: Seizures in Childhood Kitesh Moodley January 2009

Non - convulsive SE ?

• Neurologic signs after termination of SE are common:– Pupillary changes– Abnormal tone– Abnormal Babinski reflex– Posturing– Clonus– May be asymmetrical

Page 58: Seizures in Childhood Kitesh Moodley January 2009

Non - convulsive SE ?

• Up to 20% of children with SE have non - convulsive SE after tonic - clonic SE

• Particularly common in infants < 2 months

Mitchell WG. J Child Neurol 2002;17 Suppl 1:S36-43.Mitchell WG. J Child Neurol 2002;17 Suppl 1:S36-43.

Page 59: Seizures in Childhood Kitesh Moodley January 2009

Non - convulsive SE ?

• If child does not begin to respond to painful stimuli within 20 - 30 minutes after tonic - clonic SE stops, suspect non - convulsive SE– Urgent EEG

Page 60: Seizures in Childhood Kitesh Moodley January 2009

And Remember

• Airway

• Breathing

• Circulation

• Don’t

• Ever

• Forget

• Glucose