Neuro Flashcards
extradural haematoma epidemiology
- younger patients
- playing sports
- blunt force trauma to head
extradural haematoma site of bleed
middle meningeal artery at pterion
extradural haematoma presentation
- acute
- head trauma followed by acute loss of
consciousness followed by a lucid interval and
then signs of raised ICP - headache
- dilated unreactive pupil (raised ICP)
5 signs to order a CT head within 1 hour of head injury
- GCS <13 initially
- open skull fracture
- seizure
- neuro deficit
- more than 1 vomiting episode
4 signs to order a CT head within 8 hours of head injury
- older than 65
- taking anticoagulants
- dangerous injury
- amnesia of events before
extradural haematoma investigations
- urgent non-contrast CT head
- lemon shaped white blood
extradural haematoma management
neurosurgery for burr holes
extradural haematoma management
neurosurgery for burr holes
subdural haematoma epidemiology
- elderly
- falls
- alcoholics
- blood thinners
subdural haematoma site of bleed
bridging veins
subdural haematoma presentation
- usually more chronic
- gradual continuous headache
- confusion, personality changes
- raised ICP
subdural haematoma investigations
- urgent non-contrast CT head
- banana shaped, hypodense (grey) blood
(older)
subdural haematoma management
- small (<10 mm), no neuro signs: observe
- large or neuro signs:
a) burr holes if more chronic
b) decompressive craniectomy if more acute
what is uncal herniation and how does it present
- raised ICP compresses CN III
- down and out eye
- dilated fixed pupil
causes of raised ICP
- bleed
- idiopathic intracranial hypertension
- tumour
- hydrocephalus
- meningitis
idiopathic intracranial hypertension epidemiology
young obese female
signs of raised ICP
- headache
- papilloedema
- blurry vision
- vomiting
- Cushing’s triad
- uncal herniation
- reduced consciousness
what is Cushing’s triad
- bradycardia
- wide pulse pressure
- irregular breathing
describe the headache in raised ICP
bilateral
throbbing
worse in the morning
worse when lying down
worse when coughing
raised ICP investigations
- urgent CT head: midline shift
- catheter to monitor ICP
- DO NOT attempt lumbar puncture
what is the risk of lumbar puncture in raised ICP
brainstem herniation causing death
raised ICP management
i) elevate the head to 30 degrees
ii) IV mannitol
iii) remove CSF
iv) controlled hyperventilation
idiopathic intracranial hypertension management
- weight loss
- carbonic anhydrase inhibitor (acetazolamide)
raised ICP due to brain tumour management
- MRI
- IV dexamethasone
brain tumour causes
usually mets from lung, kidney, breast
how does controlled hyperventilation help raised ICP
hyperventilation reduces CO2 which constricts cerebral arteries
subarachnoid haemorrhage site of bleed
berry aneurysm in circle of Willis
risk factors for subarachnoid haemorrhage
- smoking
- hypertension
- polycystic kidney disease
- Marfan’s
subarachnoid haemorrhage presentation
- thunderclap headache
- meningism signs
features of a thunderclap headache
- worst headache ever
- occipital
- like being hit at the back of the head with a bat
subarachnoid headache investigations
i) within 12 hours do a non-contrast CT
- if normal within 6 hours then no SAH no LP
- if normal after 6-12 hours then do a LP
ii) lumbar puncture 12 hours after (only if normal CT)
- xanthochromia
subarachnoid haemorrhage management
- neurosurgery to coil aneurysm
- nimodipine to prevent vasospasm
- review anticoagulation
subarachnoid haemorrhage complications
- hyponatraemia (SIADH)
- torsades des pointes (polymorphic V-tach)
what is Wernicke’s encephalopathy and in what patients is it commonly seen
B1 deficiency in alcoholics
what are the symptoms of Wernicke’s encephalopathy
Wernicke’s triad (CAN)
1. confusion
2. ataxia
3. nystagmus
how to manage Wernicke’s encephalopathy
give Pabrinex (vitamin B1)
what is the preferred imaging in Wernicke’s encephalopathy
MRI
what is a complication of untreated Wernicke’s encephalopathy
Korsakoff syndrome
(amnesia, confabulation)
what happens to CNS receptors in alcohol withdrawal
- increased firing of NMDA receptors
- reduced GABA
what is the timeline of symptoms for alcohol withdrawal
- 6-12 hrs: anxiety, tremor, sweating, tachycardia
- 36 hrs: seizures
- 48-72 hrs: delirium tremens (hallucinations, fever)
investigations for alcohol withdrawal
Bedside:
- ECG, VBG, alcohol screen (AUDIT C)
Bloods:
- FBC (high MCV), LFTs, U&E, clotting, glucose
Imaging:
- CT head if suspecting head injury
first line management of alcohol withdrawal
diazepam (benzodiazepines)
what is myasthenia gravis
autoimmune condition against acetylcholine receptors
epidemiology of myasthenia gravis
women around 40 yrs
what are 3 symptoms of myasthenia gravis
- muscle fatigue after activity (at the end of the day improve with rest)
- diplopia
- dysarthria
what is Lambert Eaton syndrome
- muscle weakness improves with use
- associated with small cell lung cancer
investigations for myasthenia gravis
- AChR antibodies
- normal CK
- CT thorax for thymoma
- EMG: repeated stimulation decreases amplitude
what is a strong association with myasthenia gravis
- thymoma
- mass in the mediastinum
how to manage a myasthenia gravis crisis
IV immunoglobulin
first line management of myasthenia gravis
pyridostigmine (acetylcholine esterase inhibitor)
how to calculate GCS score
654 MoVE
- Movement:
6 - obeys commands
5 - localises to pain
4 - withdraws from pain
3 - flexes to pain
2 - extends to pain
1 - no movement
- Verbal:
5 - fluent
4 - confused
3 - words
2 - sounds
1 - nothing
- Eyes:
4 - spontaneously
3 - to voice
2 - to pain
1 - nothing
at what GCS score do you need to intubate
8/15
what is the triad for normal pressure hydrocephalus
- dementia
- urinary incontinence
- gait instability
