2. Neonatal Convulsion
• Seizures are more common in the neonatal period than during
any other time throughout life.
• The majority of neonatal seizures occur on the first day.
• Seizures in the neonatal period are also the most common
neurological emergency and are associated with high mortality
and morbidity.
• The Incidence of seizures in infants born at term is 0.5-3 per
1000 live births (0.1%); the incidence is even higher in preterm
infants, ranging from 1-13% (10%) of Very Low Birth Weight
Infants.
• 70% of all cases eventually recognized have been diagnosed by the
fourth day.
3. Etiology:-
• In contrast to seizures in infancy and childhood, most neonatal
seizures are acute and symptomatic with suspected specific
causes.
• Relatively few seizures are idiopathic or part of a clearly
defined epilepsy syndrome.
• Several decades ago, late hypocalcaemia due to a low
calcium:phosphate ratio in baby formula was a frequent
cause of neonatal seizures but this is very rare today.
At Term, Hypoxic Ischaemic Encephalopathy (HIE) is the most
common underlying factor, typically with onset 6–8 hours after the
hypoxic insult but within the first 24 hours of life.
In Preterm Infants, Cerebrovascular Events are the most
common cause.
• Cause seizures at any gestation:-
1. Meningitis,
2. Focal Cerebral Infarction,
3. Metabolic Disorders
4. Congenital Abnormalities of the Brain
4. Types of Convulsion:-
Generalized Tonic-
Clonic Seizures
• Are rare in the first
month of life
• Not seen in the
preterm infant due to
poor arborization of
neurons.
Focal seizures:-
• Neonatal Seizures are
usually focal
• Often short lasting
because the signal
cannot be
maintained.
5. Types of Convulsion:-
• Focal Clonic: Rhythmic muscle contractions
• Myoclonic: Random single contractions
• Focal Tonic: Sustained posturing of limb/trunk
• Spasms: Flexor or extensor, in clusters
• Generalized Tonic: Sustained symmetric posturing
• Electrographic: By definition no clinical correlate
• Motor Automatism: Ocular, oral-buccal-lingual or progression
movements of limbs (difficult to diagnose)
• Subtle seizures: chewing movements, excessive salivation,
alteration in respiratory rates, apnea, blinking eyes, nystagmus, and
color changes.
6.
7. Causes of Neonatal Seizures:-
1. Hypoxic-Ischaemic Encephalopathy (HIE) – (postasphyxial
seizures):-
▫ common cause of seizures in the full-term infant
▫ It is an insult that occurs in the fetus or newborn
▫ Results in anoxia, hypoxia or ischaemia,
▫ may injure any organ of the body, but especially the brain.
▫ Cause of around 50% of Neonatal Seizures
2. Intra-Cranial Haemorrhage (ICH):-
▫ Common cause of seizures in premature infants,
▫ occurring at 1-3 days of age.
▫ Associated with
- Bulging Fontanelle,
- Haemorrhagic Spinal Fluid,
- Anaemia,
- Lethargy,
- Coma.
3. Sepsis (Meningitis, Encephalitis)
4. Cerebral Infarction
8. 5. Congenital Brain Malformation
6. Metabolic Causes
a. Hypoglycaemia, occurs when blood glucose level declines to lowest post-
natal value (usually at either 1-2 hours of age or 1-2 days of poor
feeding)
b. Hypocalcaemia
c. Hypomagnesaemia
d. Hypo/hypernatremia
e. Hyperbilirubinemia
f. Hyperammonaenia
7. Benign Familiar Seizure
8. Drug Withdrawal Seizure
9. Unintentional Injection of Anaesthetic into fetal scalp during
labour
▫ Associated with transient bradycardia and fixed dilated pupils
10. Pyridoxine Dependency
9.
10. Seizures vs. Jitteriness
Seizures Jitteriness
Coarse, Clonic activity Fine, rapid movement
May be associated with
abnormal eye movement
Sensory dependent
EEG shows activity Interrupted by holding the
extremity
11. Pyridoxine Dependent Seizures
• Pyridoxine Dependent Seizures are a subgroup of neonatal
seizures, which are:-
- Rare
- Treatable
- Can begin in intrauterine life.
• Seizures are of multiple types.
• Usually begin shortly after birth
• are resistant to conventional antiepileptic drugs (AEDs).
• Associated with cognitive impairment if therapy is delayed.
• Pyridoxine/Pyridoxal-5’-phosphate is required for the synthesis of
several neurotransmitters, including (GABA), monoamines and others.
• When Pyridoxine Dependency is suspected, 100–200 mg of
pyridoxine should be given intravenously under EEG control.
- The seizures will abruptly stop (within minutes)
- The EEG will normalize during the next few hours.
Pyridoxine = Vitamin B6
12. Investigation:-
• Examination of the retina might show the presence
of chorioretinitis, suggesting a congenital TORCH infection.
• Septic Screen, including Blood Cultures and Lumbar Puncture
(mandatory).
• Laboratory:
- Always Glucose, Electrolytes, Blood Gas, Packed Cell Volume,
- If necessary Bilirubin, Ammoniac, Metabolic Screening, TORCH,
Screening for Drug Abuse.
• Always do Cranial Ultrasound Scanning (non-invasive),
consider MRI, EEG.
• The characteristic time of onset of seizures in HIE is 8-36
hours after birth. An EEG obtained shortly after birth in which
electrographic seizure activity was already manifest, would strongly
suggest an insult over eight hours before delivery.
• Early background EEG activity is a relatively reliable prognostic
indicator for outcome.
13. Treatment after Diagnosis
The treatment of neonatal seizures may be specific to the
identified cause, such as treatment of:
1. Meningitis
2. Hypoglycemia
3. Hypocalcemia
4. Hypomagnesemia
5. Hyponatremia
6. Vitamin B6 Deficiency or Dependency.
14. Treatment in the absence of an identifiable cause
1. Phenobarbitone remains the 1st drug of choice in the treatment of
neonates.
▫ The initial dose is 20 mg/kg in unventilated babies and 30 mg/kg in
those who are ventilator-dependent.
▫ Phenobarbitone achieves clinical control in only 30-40% of cases.
2. Phenytoin and Clonazepam are used as second-line drugs.
▫ Only started when the 40 mg/kg of Phenobarbital was ineffective.
▫ Phenytoin can cause significant myocardial depression and should be
avoided in babies requiring inotropic support. 10–20 mg/kg
▫ Clonazepam may achieve better EEG control.
3. Midazolam has a shorter half-life than clonazepam and does not
accumulate, and it avoids the side effect of increased oropharyngeal
secretions. So it has less side effects.
15. • There is little experience with Carbamazepine, Vigabatrin and
Lamotrigine in the neonatal period.
• Consider a trial of Pyridoxine, Pyridoxal-5-phosphate and
Folinic Acid.
Treatment of Status Epilepticus requires repeated doses
of Phenobarbital and may require Diazepam or Midazolam.
16. Prognosis:-
• This is mainly determined by the underlying cause.
• The prognosis is excellent (Best Prognosis) in:-
- Hypocalcaemic Seizures
- Familial Neonatal Seizures
• Symptomatic Hypoglycemia and Meningitis have a 50% chance
of sequelae in the survivors.
• In Hypoxic Ischaemic Encephalopathy the prognosis depends
very much on the grade (overall 30-50% normal), while CNS
malformations are generally associated with poor outcome.
• Very Low Birthweight Infants with Clinical Seizures have a
higher Incidence of Impairment than preterm infants without
seizures.
17. Summary:-
• The clinician needs to be aware that almost any repetitive,
stereotype movement pattern can be a manifestation of neonatal
seizure.
• Neonatal seizure typically signals an underlying significant
neurological disease.
• The most common etiology for neonatal seizure is
Hypoxic-Ischaemic Encephalopathy (HIE)
• Check Blood Glucose in any neonatal seizure.
• Investigation is required in most babies to establish a diagnosis.
19. Q1. Regarding neonatal seizures the following are true
except:
A. Hypoxic ischemic encephalopathy is the most common cause.
B. Tonic seizure characterized by alteration of respiratory rate
chewing movements and excessive salivation.
C. Examination of retina for chorioretinitis.
D. Incidence may reach up to 30% in VLBW.
or Incidence 1.8-3.5/1000 live births.
20. Q2. The following statements are true regarding pyridoxin
dependent seizures, except:
A. It is one of the rare causes of neonatal seizure.
B. Most of cases respond to a testing of 200mg of vitamin B6.
C. Six weeks trial of 10 mg of vitamin B6 is indicated in suspected
cases.
D. Most of cases improved after neonatal period .
21. 2-day-old neonate delivered by CS at 39-week gestation,
he is completely normal, but today mother bring her to
neonatal care unit with a repeated attack of Rhythmic
muscle contractions and some times sustained the
posturing of limb/trunk
Q. What is your first line of management?
A. Midazolam
B. Phenobarbitone injection
