Loss of consciousness (hydrocephalus) Flashcards
What are the causes of loss of consciousnesses in neonates
Cardiac: Aortic arch interruption, severe aortic coarctation, critical aortic stenosis
Infection: GBS, HSV
Hypovolaemia: dehydration, bleeding
Neuro: meningitis, SDH, breath holding attack, reflex anoxic seixure
Lung: congenital diaphragmatic hernias
What are the causes of loss of consciousness in teens
Vasovagal syncope
Seizure: encephalitis, meningitis, epilepsy
Cardiac: arrhythmia, long QT syndrome
Panic attacks
Pseudoseizure
Hypoglycaemia
Drug/alcohol abuse
Define hydrocephalus
Accumulation of CSF in the brain
What is the aetiology of hydrocephalus
Babies in children - hydrocephalus is congenital
Associated with cerebral malformations or obstruction to the flow of CSF → dilation of the ventricular system proximal to site of obstruction
Obstruction:
Non-Communicating: obstruction within the ventricular system or aqueduct
Communicating: failure to absorb CSF at the arachnoid villi (flow of CSF is obstructed after it exits the ventricles)
What are the causes of non-communicating hydrocephalus
Congenital malformation
- Aqueduct stenosis - usually 3rd of 4th ventricle
- Atresia of the outflow foramina of the fourth ventricle
- Chiari malformation (cerebellar tonsils herniation through the foramen magnum)
Posterior fossa neoplasm or vascular malformation
ICV haemorrhage in preterm infant
What are the causes of communicating hydrocepahlus
Subarachnoid haemorrhage
Meningitis (e.g. pneumococcal, tuberculous)
What are the symptoms and signs of hydrocephalus
In infants, as the skull sutures have NOT fused, the head circumference will be disproportionately large
The anterior fontanelle bulges and scalp veins become visible
increased tone, Ataxic gait
Papilloedema, 6th nerve palsy, Fixed downward gaze (sunset sign) is an advanced sign
Older children will develop signs and symptoms of raised ICP: headache, N&V, irritability, lethargy
Acute setting: Vomiting, irritable and impaired consciousness
Chronic setting: FTT, developmental delay
What investigations should be done for hydrocephalus
May be diagnosed on antenatal screening
Examination
Basic observations
Cranial USS
CT or MRI
Head circumference should be monitored and plotted on a centile chart
What is the management for hydrocephalus
Acute Rapidly Progressive: Endoscopic ventriculostomy with and external ventricular drain
Long Standing: Ventriculoperitoneal Shunt
- may fail due to blockage or infection → require replacement
Diuretics can decrease CSF production but NOT very effective in hydrocephalus e.g. Furosemide, Acetazolamide
Treat the underlying cause e.g. tumour, infection
If not suitable for surgery- control CV risk factors and repeated large-volume CSF taps
What are the complications of hydrocephalus
Shunts can malfunction due to blockage or infection
Infection
Mechanical failure of shunt
Over-drainage can cause low pressure headache
Epilepsy
What is the criteria for a CT scan in children
Head injury AND:
LOC >5 minutes
Abnormal drwosiness
3 or more discrete episodes of vomiting
Dangerous mechanism/high impact injury e.g. fall from considerable height, RTA, high speed injury
Amnesia >5 minutes (retrograde and anterograde)
MORE than 1 = within 1 hour
ONLY 1= OBSERVE for 4 hours
What features would necessitate CT scan within 1 hour of presentation
Suspicion of NAI
Post-traumatic seizure without history of epilepsy
GCS <14 on initial assessment or <15 after 2 hours
Suspected open or depressed skull fracture or tense fontanelle
Any sign of basal skull fracture (panda eyes, CSF leakage from ear/nose, battle’s sign
Focal neurological deficit
<1yo → Bruise, swelling, laceration >5cm on the head
