Neonatal Seizures

Seizures are a common manifestation of serious CNS disease in the newborn, and Indicate serious underlying disease (90%-95% of cases).

85% of neonatal seizure occurs in the first two weeks of life 65% occurs between 2-5 days after birth 25% in NICU in preterm neonates. And 0.8% In term infant.

Neonatal seizures may have a deleterious effect on the developing brain by depleting cerebral glucose levels, which , in turn, may interfere with deoxyribonucleic acid (DNA) synthesis and myelination.

Seizures also causes to deficiency in cell brain numbers and repeated seizures causes brain Injery.

ETLOGY OF NEONATAL SEIZURES

Gestational AgeTime of onset (days of age)

Etiology Premature Term 0-3 4-10

Hypoxic-ischemic encephalopathy intracranial hemorrhage

+ + +

Intraventricular hemorrhage

+ - +

Subarachnoid hemorrhage

- + +

Hypoglycemia + + +

Gestational AgeTime of onset (days of age)

Etiology Premature Term 0-3 4-10

Infection + + +Developmental Anomalies

+ + +

Hypocalcemia

Early onset + + +Late onset - + +

cont

Seizure type Major clinical Manifestations

Subtle

Repetitive blinking, eye deviation, staring Repetitive mouth or tongue movements apnea

Tonic (i.e. generalized or focal)

Bicycing movements’ tonic extension of limb or limbs’ tonic flexion of upper limbs’ extension of lower limbs

Clonic (i.e. multifocal or focal)

Multifocal, synchronous or asynchronous limb movements Repetitive , jerky limb movements nonordered progression Localized repetitive clonic limb movements with preservation of consciousness

Myoclonic (i.e. generalized, focal, multifocal )

Single or several flexion jerks of upper limbs(common) and lower limbs (rare)

cont.

JITTERINESS VERSUS SEIZURE

CLINCAL FEATURE JITTERINESS SEIZURE

Abnormality of gaze or eye movement

0 +

Movements exquisitely stimulus sensitive

+ 0

Predominant movement Tremor Clonic jerking

movemnts cease with passive flexion

+ 0

Autonomic changes 0 +

Movement Description

Benign neonatal sleep myoclonus

Bilateral or unilateral jerking during sleep Occurs during active sleep

Not stimulus sensitive

Often involve upper> lower trunk

CAUSES OF NEONATAL JITTERINESS

Metabolic Disorders HypoglycemiaHypocalcemiaHypomagnesemiaCNS Disorders HemorrhageHypoxia

(cont).Congenital abnormalityHyperviscosity (high hematocrit)syndorme

Drug WithdrawalHeroinMethadoneBarbituratesIdiopathicPrefeeding Others

Clinical features Neonatal seizures differ

considerably from seizures observed in older children , because the immature brain is less capable of propagating generalized electrical discharges, so primary generalized seizures are very rare in the newborn.

Diagnosis :1. Maternalal History :

A. History of drug abuse B. History of intrauterine infection C. History of Genetic or metabolic

conditionsD. Use of local anesthetic drugs during

labour.E. History of previous child with seizures

2. Nconatal Ph ex: - General ex- Neurological ex- Retinal ex- Skin ex

3- Laboratory testes: Evaluation of metabolic

diseases (Bs- ca p-Mg) evaluation of Infectious

diseases (BC-LP-Torch)Evaluation of Electrolit

disorders (Na- K)

4- Neuroimaging studies Scalp sonography (I.V. H. …) Ct scan or MRI (focal seizures) EEG Monitoring (for prognosis

& duration of therapy.

ACUTE THERAPY OF NEONATAL SEIZUES

HYPOGLYCEMIA Glucose 10% solution: 2 ml/kg. I.V.

NO HYPOGLYCEMIA

Phenobarbital: 20 Mg/kg (10-15 min) If necessary additional Phenobarbital: 5mg /kg(10-15 min) I.V. to a maximum of 20 mg/kg (consider omission of this additional Phenobarbital if infant is severely “asphyxiated”)

* Phenytoin: 20 mg/kg. I.V. (1 mg/kg/min)

lorazepam: 0.05 -0.10 mg/kg. I.V.

* Fosphenytoin: my be a preferred form of phenytion

Cont.

OTHER (AS INDICATED) Caicium gluconate, 5% solution: 4

ml/kg, I.V. Magnesium sulfate, 50%solution:

0.2ml/kg, I.M. Pyridoxine: 50-100 mg, I.V.

EXPECTED RESPONSE OF NEONATAL SEIZURES TO SEQUENCE OF

THERAPYANTICONVULSANT DRUG (CUMULATVE DOSE)

CESSATION OF SEIZURES (CUMULATIVE%)

Phenobarbital, 20mg/kg 40%Phenobarbital ,40mg/kg 70%Phenytion, 20mg/kg 85%Lorazepam, 0.05-0.10 mg/kg 95-100%

Maintenance Therapy of Neonatal Seizures

Glucose: as high as 8mg/kg/min,IV

Phenobarbital: 3-4 mg/kg/24hr , IV, IM, or PO

Pheyntoin: 3-4mg/kg/24hr IV

Calcum gluconate: 500mg/kg/24hr, Po

Magnesium sulfate (50%):0.2 ml/kg/24hr, IM

Determinants of duration of Anticonvulsant Drug therapy for

Neonatal seizuresNeonatal neurological examination Cause of the neonatal seizure Electroencephalogram

Duration of Anticonvulsant therapy-Guidelines Neonatal period If neonatal neurological examination becomes normal, discontinue therapy

If neonatal neurological examination is persistently abnormal,

consider etiology and obtain electroencephalogram (EEG) Continue Phenobarbital

Discontinue phenytoin Reevaluate in 1 month

ONE MONTH AFTER DISCHARGE

If neurologic examination has become normal, discontinue phenobarbital

If neurologic examination is persistently abnorrmal, obtain EEG If no seizure activity on EEG, discontinue Phenobarbital

Porognosis Dependent to three major

predictors: 1. the underlying aetiology2. EEG features 3. Gestational age

Other useful predictors: a- neurologic examination b- neuroimaging finding

Normal EEG neurological sequelae 10%

Moderate abnormal EEG Neurological sequelae = 50%

Severe abnormal EEG Neurological sequelae ≥ 90%

cont

contThe inedience of neurological

sequelae (mental retardation – motor deficits – epilepsy)=25%-35%)

M.R , Motor deficits (C.P) are more common than Epilepsy=15%-20%

cnotNeanatal seizures in infants

<32 weeks high mortality (80%)& higher risk of adverse neurological outcome

Overall , presentation of seizures at the first hours of life & prolonged seizures that do not respond to therapy have worse prognosis

Prognosis of Neonatal seizures by etiology

Normal outcome(%) Etiology

50 Hypoxia-ischemia

50 Meningitis

50 Hypoglycemia

90 Subarachnoid hemorrhage

50 Early hypocalcemia

100 Late hypocalcemia

10 Intraventricular hemorrhage

0 Dysgenesis

75 Unknown

Other anticonvulsant drugs for treatment of refractory neonatal

seizures:

1. Diazepam drip (continuous infusion) 0.1-0.3 mg/kg/hour

2. Midazolam drip (continuous infusion) 0.06-0.4mg/kg/hour

3. Carbamazepine10mg/kg.NG No adverse effects , but more data are needed

cont4. Valproic Acid Hepatotoxic 5. LidocainIv infusion 4-6mg/kg/hour

cardiac toxicity-BP6. Thiopental BP (more data are needed)7. Paraldehyde 0.3ml/kg/dose / PR BP

respiratory disturbance8. Primidone( more data are needed)9. Lamotrigine & topiramate (more data

are needed)