Neonatal encephalopathy Flashcards
Define neonatal encephalopathy
Disturbed neurological function:
- Difficulty initiating and maintaining respiration
- Depressed tone and reflexes
- Subnormal level of consciousness
- Often seizures
Define stage 1 mild neonatal encephalopathy
- <24 hours of hyperalertness
- Uninhibited Moro and stretch reflexes
- Sympathetic effects
- Normal EEG
Define stage 2 moderate neonatal encephalopathy
- Reduced LOC
- Hypotonia
- Decreased spontaneous movements with or without seizures
Define stage 3 severe neonatal encephalopathy
- Stupor
- Flaccidity
- Seizures
- Suppressed brainstem and autonomic functions
- ECC may be isopotential or have infrequent periodic discharges
What is the rate of moderate to severe neonatal encephalopathy in NZ?
1.3 per 1000 live births
What % of neonatal encephalopathy has risk factors?
○ 69% antepartum only
○ 25% both antepartum and intrapartum
○ 4% intrapartum only
○ 2% no risk factors identified
What is the strongest antepartum risk factor for neonatal encephalopathy?
IUGR
RR 38!
Outline the aetiology of neonatal encephalopathy
- Hypoxic ischaemic injury
- Metabolic
- Infection
- Drug exposure: cocaine, barbiturates, alcohol, TCAs, SSRIs
- CNS malformations
- Neonatal stroke (1 in 4000)
What markers increase the likelihood an acute peripartum or intrapartum hypoxic-ischaemic event contributed to the development of neonatal encephalopathy?
Neonatal signs:
- Apgars <5 at 5 and 10 mins
- Cord gas umbilical artery pH <7.0, base deficit >=12 or both.
- Acute brain injury on MRI or MRS consistent with hypoxic-ischaemia
- Multiorgan failure
Contributing factors:
- Sentinel hypoxic or ischaemic event occurring immediately before or during labour and delivery.
- CTG consistent with an acute peripartum or intrapartum event.
Discuss the utility of Apgar scoring
- Apgar scoring identifies infants that need resuscitation but can be affected by maternal drugs (GA, opiates) and other causes.
- It is a moderate level predictor of neonatal death and development of cerebral palsy.
- Apgar <7 at 5 mins OR 27 for cerebral palsy
Outline the Apgar score classifications
- Healthy Apgar score 7-10
- Primary apnoea Apgar score 4-6
- Terminal apnoea Apgar score 1-3
- Fresh stillbirth Apgar score 0
What components are included in an Apgar score?
Assesses:
- HR
- Resp effort
- Muscle tone
- Reflex irritability
- Colour
Each component is scored as a 0, 1 or 2.
What is the prognosis of neonates who have therapeutic cooling?
- 50% die or have major neurodevelopmental disability at 18 months.
- 40% have normal neuro outcome.
Seizures are associated with worse outcomes.
What are some permanent neurological sequelae of neonatal encephalopathy?
Mild:
- Learning difficulties
- ADD
Severe:
- Cerebral palsy 13%
- Epilepsy
- Visual impairment
- Severe cognitive and developmental disorders
What % of cerebral palsy cases are the result of intrapartum events?
10%