Wk 8: Neonatal seizures/neonatal encephalopathy Flashcards
Are neonatal seizures common?
Yes, relatively. Due to their immature nervous system.
- often miss diagnosed as tremors, jitteriness, startle reflex and
What are neonatal sezirues?
= paradoxical alterations in neurological function occurring in the first 28 days of life.
What are common causes of neonatal seziures?
- Hypoxic-ischaemic encephalopathy (HIE) (49 per cent)
- Cerebral infarction (12 per cent)
- Cerebral trauma (7 per cent)
- Central nervous system infection (5 per cent)
- Metabolic abnormalities including hypoglycaemia (3 per cent)
- Maple syrup urine disease
- Fatty acid oxidation defects (screened in Newborn Blood - Spot test in Postnatal period)
- Narcotic drug withdrawal (4 per cent).
- Congenital intracranial anomalies (4 per cent)
- AV malformation
What are some signs of a seziure?
- lip smacking
- ocular movements
- apnoea
- hypertension
- tachy or brady
- desat
What are the four types of neonatal seziures?
Subtle
Tonic
Myoclonic
Clonic
What are some signs of a subtle seziure?
Eye: staring, deviation, blinking etc.
Oral: chewing, sucking, lip smacking
Limbs: cycling, swimming rowing
Systemic: apnoea, tachycardia, blood pressure alterations
What are some signs of a clonic seziure?
- one limb or one side of the body jerking rhythmically at 1-4 times per second.
- Consciousness usually preserved.
What are some signs of a myoclonic seziure?
- Rapid isolated jerking of muscles.
- May be focal or multifocal.
What are some signs of a tonic seziure?
- Sustained posturing of the limbs or trunk or deviation of the head.
- It may mimic decerebrate or decorticate posturing. c
What is the management of neonatal seziures?
- monitor
- investigate underlying cause e.g. hypoglycemia
Give anticonvulsant if
- seizure is prolonger >3mins
- Frequent >2-3 per hour
associated with cardio-resp disturbance
Define hypoxic ischaemic encephalopathy (HIE)
= a type of neonatal encephalopathy caused by systemic hypoxaemia and/or reduced cerebral blood flow resulting from an acute peripartum or intrapartum event. (SCV 2019)
= Lack of sufficient oxygen to the brain and a diminished amount of blood perfusing the brain. This results in suppression of electrical activity and cortical depression (RCH 2019)
What can HIE cause?
- vision loss
- hearing loss
- speech delays
- cognitive issues
- speech delay
- epilepsy
What are some causes of HIE?
- any event the compromises Os supply to fetus (cord prolapse, placenta abruption, uterine rupture, uterine rupture)
- Asphyxia at birth, perinataly or as a neonate
- Anything that causes asphyxia e.g. placenta abruption
- Trauma
What is the management of HIE?
- therapeutic cooling
- transfer to NICU
What makes a baby eligible for scalp ccoling?
- > 35 weeks
- <6hrs post birth
Asphyxia by a least 2 of the following?
- </5 apgars at 10mins
- continued PPV needed
- any acute episode of hypoxia e.g. cord prolapse
- cord pH or <7
What is the goal temp of theraputic cooling?
33-34 degrees
15/60 temps
What should the timing of cooling be?
The total period of cooling and rewarming is for 84 hours, consists of 2 phases:
- Active cooling- for 72 hours from the initiation of cooling.
- Rewarming- 12 hours of active gradual rewarming time after completion of 72hrs of cooling.
What are some complications of therapeutic cooling?
- increased pulmonary pressure
- increased O2 requirements
- reduced surfactant production
-Electrolyte imbalance: hypokalaemia, hypo magnesia, hypophosphatemia
What is one type of neonata encelopathy?
Hypoxic-ischaemic encelopathy
What are some causes of neonatal encephalopathy?
Stroke
IVH
Congenital brain malformation
Genetic syndromes
Infection
Explain the patho phys of HIE
Phase 1: primary neurological injury
- sever cellular hypoxia during insult= exhaustion of high energy metabolism (primary energy failure)-> immediate primary neuronal death
- Reperfusion of the ischemic brain with resuscitation is followed by a latent period of at least 6 hours when energy levels “pseudo normalise”
- before the secondary energy failure and delayed neuronal death begin
Phase 2: delayed neuronal death
- A secondary loss of neurons
- Occurs 6 to 100 hours post the insult
- Cells loss is mediated by complex cellular mechanisms including apoptosis
- This phase is associated with encephalopathy & increased seizure activity
- Accounts for a significant proportion of final cell loss
What is Lissencephaly
A cerebral malformation
(meaning “smooth brain”) is a set of rare brain disorders where the whole or parts of the surface of the brain appear smooth. It is caused by defective neuronal migration during the 12th to 24th weeks of gestation resulting in a lack of development of brain folds (gyri) and grooves (sulci)
What is Polymicrogyria
a condition characterized by abnormal development of the brain before birth. The surface of the brain normally has many ridges or folds, called gyri. In people with polymicrogyria, the brain develops too many folds, and the folds are unusually small.
What is Schizencephaly
a developmental birth defect. It is characterized by abnormal slits or clefts in the cerebral hemispheres of the brain. People with clefts in both hemispheres commonly have developmental delays, delays in speech and language skills, seizures, and problems with brain-spinal cord communication.
