Neurology Flashcards
Strokes/cerebrovascular events are either:
Ischaemic
Intracranial haemorrhage
Causes of an ischaemic stroke/disruption to blood supply
Thrombus/embolus
Atherosclerosis
Shock (hypotension)
Vasculitis
What is a TIA?
transient neurological dysfunction secondary to ischaemia WITHOUT infarction
what is the significance of a TIA?
often precede a full stroke
what is a crescendo TIA?
2 or more TIAs within a week, high risk of developing into a full stroke
presentation of a stroke
asymmetrical symptoms
sudden weakness of limbs
sudden facial weakness
sudden onset dysphasia
sudden onset visual or sensory loss
presentation of a stroke
asymmetrical symptoms
sudden weakness of limbs
sudden facial weakness
sudden onset dysphasia
sudden onset visual or sensory loss
what is the ROSIER tool?
need to exclude hypoglycaemia first ***
tool for recognition of stroke in the emergency room
score >0 = likely stroke
first line radiological investigation for suspected stroke
non-contrast CT
management of a stroke
300mg of aspirin as soon as haemorrhagic stroke has been excluded
thrombolysis with alteplase - no haemorrhage, within 4.5 hours
thrombectomy
criteria for thrombectomy
offer as soon as possible and within 6 hours of symptom onset, as well as IV thrombolysis (if within 4.5 hours) to those with acute ischaemic stroke and confirmed occlusion of the proximal anterior circulation
- via computed tomographic angiography (CTA) or magnetic resonance angiography (MRA)
offer as soon as possible to those who were last known to be well between 6-24 hours, have confirmed occlusion of proximal anterior circulation, potential to salvage brain tissue proven by CT perfusion or diffusion-weighted MRI showing limited core infarct volume
consider thrombectomy with IV thrombolysis (within 4.5 hours) as soon as possible for people last known to be well up to 24 hours previously who have acute ischaemic stroke and confirmed occlusion of proximal posterior circulation & potential to salvage brain tissue
secondary prevention of stroke
clopidogrel 75mg (/aspirin plus modified release dipyridamole)
atorvastatin 80mg, but not started immediately due to the risk of haemorrhagic transformation
potential carotid endarterectomy or stenting in patients with carotid artery disease
what is the regional blood supply to the brain?
anterior cerebral - anteromedial portion of cerebrum
middle cerebral - lateral portions
posterior cerebral - medial and lateral parts of posterior cerebrum
MDT involved in stroke rehab
physiotherapists
nurses
speech and language
dieticians
occupational therapy
social services
psychology
optometry
orthotics
risk factors for intracranial bleeds
anticoagulants
head injury
hypertension
aneurysms
brain tumours
ischaemic stroke can progress to haemorrhagic (exacerbated with re-perfusion of alteplase)
presentation of intracranial bleed
sudden onset headache
seizures
weakness
nausea/vomiting
reduced consciousness
other sudden onset neurological symptoms
causes of an extradural haematoma
rupture of the MMA in the temporo-parietal region e.g. fracture of the temporal bone
what is an extradural haematoma
bleed that occurs between the skull and dura mater
bi-convex shape and don’t cross suture lines
presentation of extradural haematoma
typical history is a young patient with a traumatic head injury that has an ongoing headache
period of improved neurological symptoms and consciousness (lucid interval) followed by a rapid decline over hours as the haematoma gets large enough to compress the intracranial contents
features of raised ICP
what is a subdural haematoma
occur between dura and arachnoid layer
crescent shape, not limited by the cranial sutures
causes of a subdural haematoma
rupture of the bridging veins in the outermost meningeal layer
more common in elderly or alcoholic patients (atrophy in brains making vessels more likely to rupture)
presentation of a subdural haematoma
Slower onset of symptoms than a epidural haematoma
there may be fluctuating confusion/consciousness
principles of management of intracranial bleed
CT head
check FBC and clotting, correct any clotting abnormality
admit to specialist stroke unit, potential surgery
consider intubation, ventilation and ICU care if they have reduced consciousness
correct severe hypertension but avoid hypotension
what is a subarachnoid haemorrhage
involves a bleed into the subarachnoid space, between the arachnoid membrane and the pia mater
cause of a subarachnoid haemorrhage
traumatic vs spontaneous
spontaneous = ruptured aneurysm (berry/saccular** or fusiform)
arteriovenous malformation
Pituitary apoplexy
Arterial dissection
can be particularly associated with cocaine use & sickle cell anaemia
presentation of a subarachnoid haemorrhage
sudden onset occipital headache that occurs during strenuous activity e.g. sex, weight-lifting
‘thunderclap’ headache
neck stiffness
nausea & vomiting
photophobia
vision changes
neurological changes e.g. weakness, speech changes, reduced LOC
coma/seizures/sudden death
ECG ST elevation may be seen
conditions associated with berry aneurysms
adult polycystic kidney disease
Ehlors-danlos syndrome
coarctation of the aorta
risk factors for subarachnoid haemorrhage
hypertension
smoking
excessive alcohol consumption
cocaine use
FHx
more common in black patients, female, 45-70
investigations for subarachnoid haemorrhage
CT head - hyperdense in basal cisterns
lumbar puncture if CT is negative, but still a strong suspicion
angiography (CT/MRI) can then be used once confirmed to locate source of bleeding e.g. aneurysm/arteriovenous malformation
how does a lumbar puncture help with subarachnoid haemorrhage confirmation?
red cell count
xanthochromia
taken at least 12 hours after symptom onset to allow development of xanthochromia
**distinguish between true SAH and a traumatic tap
management of subarachnoid haemorrhage
high risk of re-bleeding, need prompt intervention (within 24 hours)
most are now treated with a coil by interventional radiologists, minority require a craniotomy and clipping
until aneurysm is treated, need strict bed-rest, well controlled BP, avoid strenuous activity
vasospasm prevented with 21 day course of nimodipine (CCB targeting the brain vasculature), treated with hypervolaemia, induced hypertension, and haemodilution
hydrocephalus = external ventricular drain or long term ventriculo-peritoneal shunt
complications of subarachnoid haemorrhage
re-bleeding** - 10% of cases, happens in first 12 hours
if re-bleeding suspected e.g. sudden worsening of neurological symptoms, repeat CT scan
vasospasm (delayed cerebral ischaemia) - 7-14 days after
hyponatremia (inappropriate SIADH)
seizures
hydrocephalus
death
important predictive factors in SAH
level of consciousness on admission
age
amount of blood visible on a CT scan
