neonatal seizures

NEONATAL SEIZURESSHINU K ANTONY

1ST YEAR MSc NURSING

DEFINITION

Neonatal seizures are the seizures that occur within the first 4 weeks of life and are most commonly seen within the first 10 days.

INCIDENCE

57.5/1,000 in infants with birth weights <1,500g

2.8/1,000 in infants weighing between 2,500 and 3.999g have seizures.

1 in 200 healthy newbornsMany seizures are very subtle – go undetected

MECHANISM

1.Large group of neurons undergo excessive, synchronized depolarization which results from –

a) Increase in excitatory neurotransmitters (glutamate)

b) Decrease in inhibitory neurotransmitters (gamma amino butyric acid- GABA

MECHANISM

c. Disruption of ATP – dependent resting membrane potentials - Failure of Na - K pump – flow of sodium into the neuron & potassium out of neuron d. Membrane alteration - Increased Na permeability

HYPOTHESIS

Inhibitory neurons are selectively damaged and remaining principal excitatory neurons became hyper excitable

Aberrant excitatory circuits are formed as a part of re organization after injury

In neonates

Immature brain has more excitatory neurons than matured (excitatory glutamate containing circuits)

GABA has a paradoxical excitatory nature in immature brain

Additionally GABA sensitive substantia nigra pars reticulata neurons play a part in preventing seizures, but in neonates it is immature

ETIOLOGY

PERINATAL ENCEPHALOPATHY

METABOLIC

INBORN ERRORS OF METABOLISM

ETIOLOGY……

INFECTIONS

DEVELOPMENTAL DISORDERS

DRUG ASSOCIATED SEIZURES

ETIOLOGY…….

THROMBOTIC DISORDERS

BENIGN FAMILIAL NEONATAL SEIZURES

HYPERTENSIVE ENCEPHALOPATHY

ETIOLOGY……

UNKNOWN OR IDIOPATHIC

HYPOXIC ISCHEMIC ENCEPHALOPATHY

Primary neuronal injury: intracellular energy failure occurs, resulting in immediate cell death by necrosis

Secondary neuronal injury occurs hours or days after the orginal insult

CLINICAL CLASSIFICATI

ONS

FOCAL CLONIC SEIZURES

Localized clonic jerking of one limb with no loss of consciousness.

The electroencephalography is unifocally abnormal .

Prognosis good. Metabolic disturbances like

hypocalcemia, cerebral contusion, focal infarct, or subarchinoid hemorrhage.

MULTIFOCAL CLONIC SEZURES

More in term infants. Characterized by random clonic

movements of limbs. Many muscle groups are involved simultaneously.

The EEG is multifocally abnormal.The prognosis is variable metabolic abnormalities like

hypoglycemia,and hypoxic-ischemic encephalopathy

TONIC SEIZURES

Seen in preterm neonates. May mimic decerebrate or decorticate

posturing. They are often associated with eye deviation, clonic movements or apnea.

The EEG is multifocally abnormal with a burst,suppression pattern or can have extremely attenuated amplitude.

The prognosis is generally poor.With diffuse cns disease or intraventricular

hemorrhage

MYOCLONIC SEIZURES

Synchronous single or multiple jerks of upper or lower limbs.

Involves distal muscle groups. The EEG shows burst-suppression pattern

or focal sharp transient waves leading to hyporrhythmia.

Diffuse cns pathology,and development defects like anencephaly.

The prognosis is poor.

SUBTLE SEIZURES

Most common type (>50%)of neonatal seizures.

They can be varied in nature and manifest variously

The EEG is often not associated with an epileptiform or hypersynchronous EEG.

They are now considered to be brainstem release phenomenon and not seizures.

Electroencephalographic Classification of Neonatal

Seizures

Clinical seizure with a consistent EEG event

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BENIGN SEIZURES

‘fifth day seizures’Benign sleep myoclonus

These are seizures occurring in well babies and all investigations are negative. Causes are

SL

NO

:

CLINICAL

FEATURES

JITTERNESS SEIZURES

1 Abnormal gaze or eye

movement

Nil Present

2 Movements Exquisitely stimulus-

sensitive

Spontaneous

3 Movements cease Passive flexion or

gentle restraint

On their own

4 Predominant movement Tremor Clonic jerking

5 Fast and slow components Absent Present

6 EEG Normal Abnormal

7 Rate or jerks 5 to 6 per second 2 to 3 per second

8 Blood pressure, heart rate Normal Increased

HISTORY

ANTENATALINTRANATALPOSTNATALFAMILY HISTORY OF SEIZURES OR

NEONATAL DEATHSNEUROCUTANEOUS MARKERS

Investigations

CBCBlood – glucose, calcium, Na, K, Mg,

bilirubin, ABG, LFTCSF analysisBlood C/S , urine C/SCranial USG

Second line investigations

TORCH screeningIEM screening – urine organic acids - S. amino acid assayMetabolic disorders – s.ammonia, ABG

Investigations….

Imaging – CT scan - MRI - EEG brain:Routinue neonatal

EEG recording, Amplitude integrated EEG (aEEG)

Management

Collect all samples IV lineThermoneutral environmentGlucose 10% - 2-4ml/kg as bolus followed

by 10% glucose as drip @ 8mg/kg/minIV calcium – gluconate 2ml/kg

Management…..

If significant seizures persists, midazolam 0.15mg/kg IV bolus followed

by IV infusion 0.1-0.4mg/kg/hr (0.2-0.6mcg/kg/min).

sodium valporate IV is the usual next drug in case of resistant seizure (20-25mg/kg/day).

Vigabatrin (50mg/kg/day) and topiramate (3mg/kg) are experimental at present.

Further management

Maintenance dose of anticonvulsants is started 12hours after loading.

Initial maintenance doses are given as intravenous and later switched over to oral.

If on multiple anticonvulsants and seizures free for 2-3 days then try to taper on to monotherapy

If controlled with calcium gluconate, start maintenancce dose

If the baby is seizures free after 1 or 2 episodes and with normal neurological status or there is a known cause for seizures then anticonvulsant may be stopped on discharge.

If the baby had difficult to control seizures or if baby is neurologically abnormal then anticonvulsants may be continued and consider a neurology consultation

ANTICONVULSANT DRUG DOSES

DRUG INITIAL DOSE MAINTENANCE

Phenobarbital 20mg/kg IV. Consider further 5-10mg/kg

increments to a total of 40mg/kg

Check drug levels may not

need further doses for many

days 3-4 mg/kg/day

Phenytoin 20mg/kg IV. Fosphenytoin 20mg /kg IV 3-4mg/kg/day divide bid to

qid

benzodiazepines Lorazepam 0.05-0.1 mg/kg IV. Diazepam

0.3mg/kg IV

INITIAL MANAGEMENT OF ACUTE METABOLIC DISORDERS

Hypoglycemia Dextrose 10% 2-3ml/kg IV

Hypocalcemia Cacium gluconate 5% (50mg/ml), 100-200mg/kg IV 10%

(100mg/ml) 50-100mg/kg IV if inadequate time for dilation

Hypomagnesemia Magnesium sulphate 12.5% (125mg/ml) 50-100mg/kg IV

Hyponatremia Furosemide 1mg/kg IV. 3% Na Cl 1-3ml/kg over 15to 30 mts

PROGNOSIS AND OUTCOME

Level of maturationMetabolic abnormalitiesSevere grades of IVH and congenital malformations

Seizure patternEEG

National Collaborative Perinatal Project

Apgar <=6 at 5 minutes or longerThe need for positive pressure ventilation > 5

minutes after birthEarly onset of seizures within 24hrsHypotonia at 5mts or longer following birth3 or more days with uncontrolled seizuresPresence of tonic or myoclonic seizuresSeizures lasting longer than 30mtsNeed of more than one anticonvulsant drug for

control of seizures

NURSING

MANAGEMENT

NURSING ASSESSMENT

Health historyPhysical examination

NURSING DIAGNOSIS

Decreased intracranial adaptive capacity related to compression of brain tissue due to increased intracranial pressure resulting from brain injury

Risk for ineffective (cerebral;) tissue perfusion related to increased ICP alteration in blood flow secondary to hemorrhage, vessel malformation or edema

NURSING DIAGNOSIS……..

Risk for injury related to altered level of consciousness, weakness, loss of muscle coordination secondary to seizure activity

Disturbed sensory perception related to presence of neurologic leisions or pressure on sensory or motor nerves secondary to increased ICP as evidenced by nystagmus, loss of response to stimuli

NURSING DIAGNOSISI……

Risk for infection related to surgical interventions, trauma to brain, stasis of pulmonary secretions and urine

Imbalanced nutrition less than body requirement related to vomiting and difficulty feeding

BIBLOGRAPHY

John Cloherty P, Eric Eichenwald C, Annie, Hansen R, Ann Stark. Manual of neonatal care.7th ed. South Asia: Lippincott, Williams and Wilkins; 2012

Santhosh Kumar A. manual of newborn care. 2nd ed. Newdelhi: Paras medical publishers; 2011

Dipak Guha K. Guha’s Neonatology: Principles and Practice. 3rd ed.Jaypee publication.

Dorothy Marlow R, Barbara Redding A. Text Book of Paediatric Nursing. 6th ed. Elsevier publication.

David Wilson, Marilyn Hockenberry J.Wong’s Clinical Manual of Paediatric Nursing. 8th ed. Elsevier publication.

Kliegman, Stauton, Geme S T, Schor, Behrman. Nelson’s Textbook of Pediatrics.Vol II 19th ed. Philadephia:Elsevier publishers.2012

Maggie Meeks, Maggie Hallsworth, Helen Yeo. Nursing the Neonate. 2nd ed. Wiley Blackwell publication.

Terrikyle, Susan Carmar. Essentials of Pediatric Nursing. 2nd ed. Phiadephia: Wolters Kluwer Health publishers.2010