9716neonatal seizures
TRANSCRIPT
-
7/30/2019 9716Neonatal Seizures
1/19
Neonatal Seizures and
management
Dhaka Sishu hospital
Bangladesh
-
7/30/2019 9716Neonatal Seizures
2/19
Objectives
Introduction
Types/ Differential Diagnosis
Investigations
Management
Areas of Uncertainty in Clinical Practice
Prognosis
http://rwh.org.au/nets/handbook/index.cfm?doc_id=602http://rwh.org.au/nets/handbook/index.cfm?doc_id=602http://rwh.org.au/nets/handbook/index.cfm?doc_id=602http://rwh.org.au/nets/handbook/index.cfm?doc_id=602http://rwh.org.au/nets/handbook/index.cfm?doc_id=602http://rwh.org.au/nets/handbook/index.cfm?doc_id=602http://rwh.org.au/nets/handbook/index.cfm?doc_id=602http://rwh.org.au/nets/handbook/index.cfm?doc_id=602http://rwh.org.au/nets/handbook/index.cfm?doc_id=602http://rwh.org.au/nets/handbook/index.cfm?doc_id=602http://rwh.org.au/nets/handbook/index.cfm?doc_id=602http://rwh.org.au/nets/handbook/index.cfm?doc_id=602http://rwh.org.au/nets/handbook/index.cfm?doc_id=602http://rwh.org.au/nets/handbook/index.cfm?doc_id=602 -
7/30/2019 9716Neonatal Seizures
3/19
Introduction
Neonatal seizures are paroxysmalalterations in neurological function. This
definition allows the inclusion of clinical
seizures associated with EEG
abnormalities as well as paroxysmal
clinical activities (lip smacking, cycling
etc.) that are not associated with EEG
alterations.
-
7/30/2019 9716Neonatal Seizures
4/19
Relatively high incidence of seizures (13
per 1000 term infants and in preterm-10
to15/1000). Rarely idiopathic.
-
7/30/2019 9716Neonatal Seizures
5/19
Aetiology of neonatal seizures:
The main causes are: Hypoxic-ischaemic encephalopathy (HIE)
Intracranial haemorrhage : subarachnoid (term >preterm), subdural (term infants with difficult
deliveries) and peri/intraventricular (preterminfant)
Cerebral infarction (stroke) : term infants
Congenital CNS structural abnormalities /
cortical dysplasia (neuronal migration disorderscausing cerebral cortical dysgenesis).
Intracranial infection : meningitis > encephalitis
-
7/30/2019 9716Neonatal Seizures
6/19
Less common causes are:
Inborn error of metabolism: amino and organic
acidopathies, often seen after the infant startsfeeding.
Electrolyte disturbances: hypoglycaemia,hypocalcaemia, hypomagnesaemia, hyper- andhypo- natraemia,
Pyridoxine deficiency Neonatal drug withdrawal
Trauma: delivery and non accidental injury
Benign familial neonatal seizure syndromes: AD, szoften start on day 2-3 and cease 6 months
Benign idiopathic neonatal seizures at day 5 of life(ie, fifth day fits)
Unknown aetiology / idiopathic : 2 - 5%
Progressive epileptic syndromes in the first year oflife with onset in the neonatal period
-
7/30/2019 9716Neonatal Seizures
7/19
TYPES
-
7/30/2019 9716Neonatal Seizures
8/19
Type Clinical manifestation Comments
Subtle
50-75%
Eye signs: staring, deviation, blinking
etc
Buccal-oral-lingual: chewing,sucking, lip smacking
Limbs: cycling, swimming rowing
Systemic: apnoea, blood pressure
alterations
It may be difficult to differentiate
subtle seizures from extremes
of normal behavior. Many subtle
seizures are thought to arisefrom the basal ganglia as a
result of diminished cortical
inhibition. Further depression of
the cortex with anticonvulsants
may not alter these seizures
Clonic
23-40%
Repetitive jerking, usually involveone limb or one side of the body
at 1 4 times per second.
May be a clue to an underlying focal
neuropathology e.g.
hemorrhage or cerebral
infarction
Myoclonic
8-18%
Rapid isolated jerking of muscles.
Focal, multifocal or generalizedD/D- benign sleep myoclonus.
Seen in drug withdrawal (especially
opiates). If it occurs during sleep
then it is probably "benign
neonatal sleep myoclonus". Canalso occur in a very severe form
of encephalopathy.
Tonic
2-10%
Sustained posturing of the limbs or
trunk or deviation of the head. It
may mimic decerebrate or
decorticate posturing. Only 30%have EEG correlates.
Often difficult to treat with
anticonvulsants
-
7/30/2019 9716Neonatal Seizures
9/19
Movement Description
Jitteriness
Symmetrical rapid movements of the hands and
feet
Stimulus sensitive, and may be initiated by
sudden movement or noise or spontaneous.
Suppressed by holding the limb.No associated eye movements
Benign neonatal
sleep
myoclonus
Bilateral or unilateral jerking during sleep
Occurs during active sleep
Not stimulus sensitive
Often involve upper > lower trunk
Differential diagnosis
-
7/30/2019 9716Neonatal Seizures
10/19
Management
Immediate management includes-Stabilization-evaluation of ventilation and
perfusion.
Identification of the cause and specifictreatment.
If needed, administration of an
antiepileptic drug (AED) to prevent seizurerecurrence.
-
7/30/2019 9716Neonatal Seizures
11/19
Investigations:
All newborns with seizures :
Blood glucose level
Electrolytes: Na+, Ca2+, Mg2+
Full blood count
Cranial ultrasound: to exclude gross
CNS pathology, but is not effective at
detecting subdural and epidural bleeds
or identifying parenchymal injury.
-
7/30/2019 9716Neonatal Seizures
12/19
Further investigations :
Acid base status
Blood culture
Lumbar puncture: for CSF study.
Specimens for virology and congenital infections:TORCH (toxoplasmosis, rubella, CMV, herpes)
Metabolic screen: urine for amino and organic acids
Metabolic screen: blood for ammonia, lactate, pyruvate.
Neurophysiology: formal 12 lead EEG, continuousEEG(BRAINZ monitor)
Neuroimaging: CT, MRI
-
7/30/2019 9716Neonatal Seizures
13/19
Anticonvulsant medication: Indication for treatment of clinical seizures:
Prolonged > 3min
Recurrent > 3 in 1hour Associated with cardiorespiratory compromise.
Therapy:
Start with Phenobarbitone. If seizures are not controlled withmaximum phenobarbitone, add Phenytoin.
Drug levels should be monitored to determine maintenance dosagesbecause of the variable pharmacokinetics in this age group.
If a combination of phenobarbitone and phenytoin is ineffective, thenthe options for achieving complete seizure control become limited.Clonazepam as a third line agent, .. In a recent report. Lignocaineappeared to be superior to clonazepam or midazolam.
A trial ofPyridoxine should be performed in conjunction with EEGmonitoring if pyridoxine deficiency is suspected in an infant withintractable seizures who does not have an underlying aetiologydetermined. Documenting cessation of seizures and normalisation ofthe EEG within minutes of IV pyridoxine often makes diagnosis.
-
7/30/2019 9716Neonatal Seizures
14/19
Anticonvulsant Indication for
treatment
Loading dose Maintenance Other
consideratio
ns
Phenobarbitone Seizures duration:
3 minutes
OR
Seizure
frequency: 3
per hour
20 mg/kg IV over 30 minutes.
If initial dose is ineffective an
additional 510 mg/kg can
be administered every 5
minutes, up to a total of 40
mg/kg
4 mg/kg/dose
IV/ oral
every 12h
Start 24 hours
after the
loading
dose
Therapeuticlev:4
0130
mol/L
Needs
cardiorespira
tory
monitoring
Phenytoin Inadequate response
to
phenobarbitone
20 mg/kg IV over 30 minutes 4 mg/kg/dose
IV every
12 hStart 12 hours
after the
loading
dose
Therapeutic level:
40-80
mol/LNeeds
cardiorespira
tory
monitoring
Clonazepam Inadequate response
to
phenobarbitone
and phenytoin
0.025 mg/kg/dose IV stat 0.025
mg/kg/dos
e every 8
hours
Needs
cardiorespira
tory
monitoring
Pyridoxine Intractable seizures
with no
underlying
aetiology
determined
100 mg IV or IM stat
(test dose)
50100 mg
daily oral
Pyridoxine trial
(s) to be
performed
with EEG.
-
7/30/2019 9716Neonatal Seizures
15/19
Areas of Uncertainty in Clinical Practice
Duration of therapy and decision to stop anticonvulsantmedication is entirely empiric and should be judged onan individual basis taking into account the neurologicalexam, aetiology of seizures and interictal EEG.
Withdraw anticonvulsants once seizures are controlled
and neurological examination is normal. There is no indication that prolonged treatment of
anticonvulsant therapy reduces the risk for the laterdevelopment of epilepsy.
The only recommendation for continuing anticonvulsanttherapy (phenobarbitone 3-4 mg/kg/day) is in the settingof profound neonatal encephalopathy or severe braininjury and then only for 6-8 weeks.
-
7/30/2019 9716Neonatal Seizures
16/19
Consequences
Short term: Prolonged seizures maycause
Hypoxia Arrhythmia
Lactic acidosis Hypoglycemia Hyperkalemia Hyponatremia
Myoglobinuria Hyperpyrexia
-
7/30/2019 9716Neonatal Seizures
17/19
Long term: Prognosis depends on the:
Aetiology of the seizures.
Neurological exam: Persistent neurological abnormalities are associatedwith poor outcome
Gestational age: Adverse neurodevelopment outcome of cognitive changes,developmental delay , cerebral palsy . Seen in 20 40% of term and up to75% of preterm infants. [9.3% in term & 33.3% in preterm babies with
asphyxia (HIE-2,3), Mahbub et al DSHJ;2004;20:30-33]
Seizure characteristics: Increased likelihood of adverse / poor outcomeassociated with
Seizure type: Subtle, generalised or 2 or more seizure types.
Prolonged or poorly controlled.
EEG background: If there is persistent low voltage or burst suppressionpattern this correlates with poor neurodevelopmental outcome in 65 to 90%.
-
7/30/2019 9716Neonatal Seizures
18/19
Summary Neonatal seizures are relatively common and rarely
idiopathic
There are four different types of clinical seizures
Seizures must be differentiated from jitteriness andbenign neonatal sleep myoclonus
Treat with anticonvulsants if the seizure is prolonged(longer than 3 minutes), frequent or associated with
cardiorespiratory disturbance
70% of seizures will abate with phenobarbitone only
-
7/30/2019 9716Neonatal Seizures
19/19