Strokes & haemorrhages Flashcards
What is TIA
Definition: Acute loss of cerebral/ ocular function with sudden symptoms lasting less than 24 hours mainly due to vascular compromise (atherothromboembolism from an artery)
→Temporary focal cerebral Ischaemia due to lack of oxygen → No Infarction!
→Symptoms maximal at onset and usually last 5-15 minutes
Which artery are most associated with TIA
90% - Carotid artery affect
Hemiparesis, hemisensory loss, hemianopic visual loss aphasia, amaruosis fugax
10% - Vertebrobasilar artery
TIA dx
1st line - Diffuse weighted CT/MRI
2nd line - carotid doppler US
if + CT Angiography
TIA tx
Loading dose of aspirin 300mg + refer to speciallist within 24hrs of onset
Long term
Antiplatelet therapy: aspiring + clopidogrel
+Stating
If artery >70% stenosed - carotid endaarterectomy
What are the different types of strokes / haemorrhages?
Stroke:
Ischaemic: Embolism = reduced perfusion= ischaemia and infarction
Haemorrhage = rupture of blood vessel => Infarction
Can also have global ischaemia - whole brain Hypoperfusion ~ MI
STROKE RF
Age
IHD
Diabetes
HTN
Smoking
Male
Hyperlipidiemia
PVD
Clotting disorders
vasculitis
alcohol
Vasculities
Infective endocarditis
Carotid bruit
How to investigate a stroke?
Clinical recognition: FACT: Face, Arms, Speech, Time
**
1st line - NC-CT - differentiates betweem haemorrhage and infarction
2nd- Diffuse weighted imaging MRI
3rd - CT angiogram if going for thrombectomy (Ischaemic Stroke)**
Other
Bloods - Rule out other causes:
Glucose (Hypoglycemia)
FBC (Polycythemia)
ESR (Vasculitis)
INR (if on warfarin)
ECG - AF /MI
How are stroke classified
BAMFORD CLASSIFICATION
How would a stroke present if ACA was affected?
+ Gait, Incontinence
Drowsiness (frontal lobe affected)
How would a stroke present if MCA was affected?
How would a stroke present if PCA was affected?
MOST COMMON PX
visial agnosia - cant interpret visual info
propagnosia - inability to recognise faces
How would a stroke present if
Vertebrobasilar artery was affected?
Quadriplegia
Dysarthria & speech impairment
Vertigo, nausea, vomiting
LOC/Drowsiness
If basilar - LOCKED IN SYNDROME
Lacunar Infarction
Lacunar infarct - Small perforating artery occlusion supplying subcortical area (internal capsule, basal ganglia, thalamus, pons)
one of:
Hemiplegia
Homoyomous hemianopia
higher cortical dysfunction - dysphagia/negleect/dysarthia
Treating strokes?
If stroke is confirmed (CT excludes haemorrhage)
1st - Loading doese of aspiring 300mg aspirin / 2wks then clopidogrel 75 mg life
Definitive TX
within 4.5 hrs of sx - Thrombolysis with Alteplase
Within 6 hours
Thrombectomy with CT angiography
what is an intracerebral heamorahage
Sudden bleeding into brain tissue due to rupture of blood vessels, leading to infarction due to O2 deprivation. Pooling of blood increases ICP.
10% of strokes, 50% mortality.
MOST COMMONly due to HTN
What are the causes of an intra-cerebral haemorrhage
HTN - causes stiff brittle vessels ; prone to rupture
Secondary to ischaemic stroke, bleeding after reprefusion
vasculitis
Brain tumour
Treating intracerbral haemorrhages?
Coagulation -
Stop anticoagulants immediately
Reverse with clotting factor replacement if needed (Beriplex + vitamin k if on warfarin)
AGGRESIVE BP control -
<6 hours after onset
Aim to lower below 140 mmHg systolic
(CI - Poorly, Comatosed, early surgery)
Nimodipine - CCB
Reducing ICP - (Cushing’s NX triad)
IV mannitol
Mechanical ventilation if needed
Neurosurgical referral -
Decompressive craniectomy
TO NOTE: if stroke was in Left -MCA of right handed patient>
Likely to see expressive aphagia, and receptive aphagia
cant speak or understand
this is due to broca’s area and wernicke’s area
In the non-dominant side - hemisensory loss
What are the different types of heamorrhages? and what are the global signs?
Subarachnoid haemorrhage
Subdural Haemorrhage
Epidural haemorrhage
Global SX: Headache, HTN, Altered mental state (confusin, syncope,seizure), HTN + Focal neruological deficit
How would brain haemorrhages appear on a NC-CT?
Intra-cerebral haemorrhage - Hyperdense lesion
Subarachnoid haemorrhage - Star Shaped - blood in basal cistern
Subdural haemorrhage - Cresent shaped lesion +/- evidence of midline shift (Hyperdense then hypodense over time)
Epidural haemorrhage -Hyperdense Lens shaped lesion +/- midline shift
Features of Subarachnoid haemorrhage?
Definition: Spontaneous bleeding between arachnoid and pia mater usually due to rupture of a cerebral aneurysm.
MC - Communicating branches of the circle of Willis.
35-65
Very severe - 50% dead, 50% sever disability
RF - CTD, PKD, Bleeding disorderm coartication of aorta, ^^% berrys aneurysm
Pathophsyiology of Subarachnoid haemorrhage
Blood loss / hypo perfusion - ischaemia and cell death
Severe Thunderclap Headache
Raised ICP - blood into cranial space (Hydrocephalus)
Blood in SA space:
* Irritates meninges - Meningism (Photophobia, neck stiffness, Kernig’s sign, Brudzinki’s Sign, 3rd nerve palsy - fixed dilated pupil, droopy eyelid)
* Irritates arties - vasopasm - further reducing perfusion
SAH IVx and TX
CT - Star shape lesion (basal cistern blood infiltration)
Lumbar puncture >12hrs = Xanthocromia
yellow CSF - from broken RBC
MR/CT Angiography - localizes source
TX:
IV mannitol
CCB nimodipine (reduces vasospasm)
Neurosurgery - Endovascular coiling
Features of subdural haemorrhage?
Definition – Accumulation of blood between the arachnoid and dura mater, usually due to the rupture of a bridiging vein. Can be acute (~big trauma) or chronic (~older patients)
~~ w/ shearing forces - shaken baby syndrome / deceleration injury
Epidemiology + RFs:
More common in elderly and alcoholics (brain atrophy and increased falls)
Most due to trauma
Anticoagulation
Pathophsyiology of subdural hematoma?
Bleeding from bridging veins into subdural space
=Forms a haemotoma (clot) which stops the bleeding
Weeks/months later the clot autolyses – clot draws water in and expands
Gradual increase in ICP => Midlinee shift + Herniation and coning (Uncal herniation) => Coma + Death
Cushing triad ~^ICP (Bradycardia, wide pulse pressure, irregular breathing)
Subdural hematoma sx
Acutely
Fluctuating consciousness
Drowsiness
Headache
Confusion
Behavioral change
Signs of ICP – vomiting, nausea, seizure, raised BP
Coma – many present with this
Chronic - Slow onset w/ latent period
Subdural hematoma IVx
CT head –
Acute: Hyperdense crescent shape
Chronic: Hypodense crescent shape
how to treat Increased ICP?
Bed position - tilt head 30 degrees
intubation
O2
osmotherapy (iv mannitol/hypertonic saline)
Subdural haematoma TX
Starts with basics – ABCDE, Start oxygen, Maintain systolic BP >90 mmHg
Neurosurgery:
Burr hole – irrigation + evacuation
Craniotomy – to reduce ICP acutely
IV mannitol – reduce ICP
What is an epidural haematoma?
- Definition – Collection of blood between the dura mater and the bone usually cause by head injury resulting in the fracture of temporal/ parietal bone (ptrieon space) and subsequently rupture of middle meningeal artery
Always suspect this after a traumatic head injury with low conscious levels falls or slow to improve or lucid interval.
~ present in young adults
How would an epidural hematoma present?
Head injury
Brief LOC or drowsiness
Lucid interval – haemotoma is still small, can last hours to a few days
Followed by rapid decline, severe headache, vomiting, confusion, seizures, raised ICP - cusing triad
Epidural IVx
CT head – Gold standard
Shows hyperdense biconcave region that is adjacent to the skull
Epidural TX
ABCDE assessment
IV Mannitol
Neurosurgery – Clot evacuation, ligation of middle meningeal artery
May need intubation and ventilation
