convulsions (seizures)
DESCRIPTION
seizureTRANSCRIPT
CONVULSIONS (SEIZURES)
PROF. DR. SHAHENAZ M. HUSSEIN
Seizures
Definition:- A seizure is the clinical event that result from abnormal
excessive neuronal activity. Etiology:- -Alteration of consciousness, motor activity, behavior, sensation or
autonomic function.-It may be viewed as a symptom of an underlying disease process.Classification:-• Acute non recurrent convulsions:-One or more convulsive fits that occur during the same acute illness &
do not recur after recovery:-– Febrile convulsions. – hypertensive encephalopathy.– CNs infections:- meningitis, encephalitis.– Intra cranial Hemorrhage: spontaneous, or traumatic – Toxic:- e.g tetanus. – Intracranial tumors.– Anoxic:- sudden severe asphyxia.– Metabolic:- hypoglycemia, hypocalcaemia, hypo or
hypernateremia.
• Chronic recurrent convulsions:-Recurrent attacks of convulsions with symptoms free intervals:-
*Epilepsy: -- Idiopathic. --Neurocutaneous synd. Such as Sturge-weber,
neurofibromatosis, tuberous scelosis.–Organic secondary to brain insult:- post- infection,
post- traumatic, post- hypoxic, post- toxic.– Benign neonatal convulsions. *Degenerative brain disease.*Congenital cerebral malformation.
Electrical rhythm in epilepsy
EpilepsyDefined as Increased Neuronal Excitability•
• Partial:- Epileptic focus start localized and remain localized:
Classified according to level of consciousness:– No loss of consciousness: Motor – Sensory – Autonomic.– Loss of Consciousness: Temporal lobe epilepsy.
• Generalized:- Epileptic focus start localized then become generalized.
– Grandmal – Febrile - Status epilepticus – Myoclonic – Clonic – Atonic.-- Petite mal (typical and atypical) – Tonic.
• Unclassified
Generalized tonic clonic(grand-mal epilepsy)
The commonest form of childhood convulsions 60%:--An aura:- unusual behaviors recognized by the mother. -Tonic phase:- powerful sustained contraction(5 minutes):-
– The patient falls to the ground stiff due to powerful sustained contraction of all muscles.– Arm flexed - Legs extended.
-Clonic phase:- Rhythmical contraction and relaxation of muscles of limbs and face:- Biting the tongue and incontinence may occur during the clonic phase.
-Duration of attack is variable but if exceed 20 minutes it considered status epilepticus.
-Post epileptic phase:- The child falls in deep sleep and afterwards he may be confused or irritable.
Grand-mal epilepsy has good prognosis if the first attack start after the age of 3years and the mental development is normal.
Febrile convulsionDefinition:- Generalized tonic clonic convulsions which
occasionally occur at the onset of acute extra-cranial infections.
Incidence:- 3-5% in all children.
Etiology:- At the onset of acute extra-cranial infections such as
tonsillitis.- Febrile seizures may signify a serious underlying acute
infections.- In association with high environmental temp.Clinical picture:- Criteria for diagnosis of simple febrile convulsions:-
–Patient type:- Age: 6month to 6years. - Sex: male more than female. –Family history: Strong positive.
- Neurologically & metabolically free.
Seizures stages:- –Pre- Ictal:- Convulsions occur at the onset of
temperature 39o c or more.– Ictal:- Generalized tonic clonic.–Short duration:- 5-15 minutes.–Course:- Usually one convulsive fit during
the same illness.–Post-ictal:- Short postictal stupor.
Investigation Laboratory:-CSF analysis: Indicated if any doubt exist regarding
the possibility of meningitis.EEG:- Indicated in atypical febrile seizure persists for more
than 15 minutes or recurrent more than 3 time/day, or focal seizures.
A child at risk for developing epilepsy:-– Positive family history of epilepsy – Initial febrile seizures before the age of 6 months. – A febrile seizure.– Delayed developmental milestone.– Associated Respiratory manifestation (cyanosis).
Prognosis:- Risk for developing epilepsy is 1% in children without risk factors,9% with risk factors.
Treatment:-– Immediate first aid measures.–Measures to lower the temperature:- Cold fomentation / Antipyretics. –Treatment of the cause of fever e.g Antibiotics
for acute tonsillitis.–Short acting anticonvulsant:- Diazepam (valium)
0.25mg/kg/dose.
Generalized absence = petit-mal epilepsy- The commonest age 5-9 years.- Rare below 2years and never continue after 15 years.- Short sudden loss of consciousness.- The child suddenly stops talking and stares for few
seconds.- Recovery is immediate and child resumes talking.- Not associated with limb movement.- Recurrent up to more than 100 times/day.- May affect school performance.
Myoclonic epilepsy- Occurs at any age but is more seen in infants and young
children.- Usually associated with mental retardation.-The attack which is very frequent, present with sudden
symmetrical mass jerking involving all limbs.
Juvenile myoclonic epilepsy-Occurs during adolescence –A.D. -Chromosome No. 6–The hallmark is morning myoclonus within 90 minutes after
awakening.-Resolved with Valporic acid therapy for life.
Atonic (a kinetic) epilepsy- It is a type of myoclonic epilepsy.- Transient loss of consciousness and falling on the ground.- Then immediately the child gets up and resumes activity.- The condition may be confused with petit mal.
Benign neonatal convulsions-A.D. - Chromosome No. 20-Generalized clonic seizures -Occurs toward the end of the 1st week of life.-Called familial 5th day fits.-Favorable prognosis.
Infantile spasm ( West syndrome)
• Brief convulsion of the neck, trunk and arm muscles followed by sustained muscle contraction lasting 2 to 10 seconds.
• Occurs when the child awakening or going to sleep.• Each jerk is followed by a brief period of relaxation, many clusters occurs
each day.
• EEG showed Hypsarrhythmia ( high- voltage slow waves, spikes and polyspikes).
• Peak age 3-8 months. - It could be mistaken for infantile colic.
• Treatment by ACTH,or oral steroids, or benzodiazepines,or valproic acid and vigabatrinis also promising.
Status epilepticusDefinition:- Continuous convulsion or repeated convulsions
without return of the level of consciousness more than 20 min.
Causes:- -Sudden withdrawal of anticonvulsant. -Febrile convulsion in poorly controlled epileptic
patient. -Metabolic or toxic.
Management:1-Stop the convulsion by:-- Diazepam 0.2 – 0.4mg / kg / dose I.V. or 0.5mg/kg/dose
rectally.- Chloral hydrate or paraldehyde:- 0.15 mg/kg diluted in saline
I.V or 0.5ml/kg/dose rectally- If failed give general anesthesia (short acting barbiturates).
2-Long-term anticonvulsant:- – Phenobarbitone 3-5mg/kg/day.– Diphenylhydantoin 5-8mg/kg/day.
3-Evaluation of the patient: After the attack Todd's paralysis may occur and then resolve completely.
Partial (focal) seizures• Motor : Jacksonian epilepsy (simple partial motor seizures):-
– Involve the motor area of the brain and the patient is alert.
– Consists of clonic movements in a localized group of muscles. Commonly at the Corner of mouth, Thumb, and Great toe.
– Jacksonian march:- The neuronal discharge may spread to other parts on the same side or become generalized.
– Rarely may continue for hours or day (epilepsia partialis continue).
– After the attack, there may be weakness of the part involved (Todd's) paralysis.
• Sensory seizures:- (simple partial sensory seizures):-– Localized or spreading parasethesia:- tingling,
coldness, numbness electricity or even pain.
• Autonomic seizures- (simple partial autonomic seizures):-
Autonomic manifestation: -Sweating. - Tachycardia.– Diarrhea or Constipation. – Hypertension.– Abdominal pain (abdominal epilepsy). – Pupillary dilatation or constriction.
Temporal lobe (psychomotor)Partial complex epilepsySequence of events:-
– Aura:- blinking of eyes, abnormal sound, taste, smell or movement.
– Absence:- loss of consciousness.– Automatism:- automatic movements e.g: chewing,
smacking of lips.– Amnesia:- recent amnesia for all events during the
attack.
Treatment of epilepsyDuration of therapy:-
– 3 or 4 years after the last convulsions in grand-mal or petit mal epilepsy in an otherwise normal child.
– Longer period or even life long for those with associated neurological problems.
• Advice to parents & child:-– Give full information about the drug therapy
and stress on not to stop the drug without medical advice.
– Allow normal activities:- the child should be attended by a responsible adult while bathing or swimming.
– Give clear instructions about the first-aid measures in case the seizures:
1. Ensure patent airway. 2. Avoid biting the tongue 3. Putting the child in the prone or side position with head
down.
• Anticonvulsants:
Type of seizures Drug of choice Daily dose Side effects
Neonatal Phenobarbitone 3-5 mg/kg Irritability,overactivity
Grand-mal Na-Valproat, Phentoin,
Carpamazepine
10-20mg/kg 4-8mg/kg
10-20mg/kg
-Hepatic dysfunction -Ataxia,gum hypertrophy. -Rash, Leucopenia, hepatic dysfunction
Focal motor Carpamazepine 4-8mg/kg Rash, Leucopenia, hepatic dysfunction
Psychomotor Carpamazepine 4-8mg/kg Rash, Leucopenia, hepatic dysfunction
Myoclonic, Akinetic Clonazepam 0.05-0.2mg/kg Drowsiness, salivation, sedation
Petit-mal Ethosuximide 20-40mg/kg Rash, Leucopenia, hepatic dysfunction
Status Epilepticus Diazepam 0.2-0.4mg/kg Respiratory depression
New drugs used for treatment of epilepsy:-For generalized seizures:• Lamotrigine• Topiramate• Zonisamide-For partial seizures:*Gabapentine-For Infatile spasm:*Topiramate*Vigabatrin