Prevention and Treatment of Stroke

Question 1

diagnosing stroke

Answer 1

has a stroke occurred?
what type of stroke?
how severe is the stroke?
can it be treated?
whats the underlying cause?
(throughout this process, patients often cant speak for themselves)

patients will be asked:

• family history
• symptoms
• how long symptoms occurring for
• neurological exam (what brain region)
• risk factors (high blood pressure, diabetes)

Question 2

Ischaemic stroke

Answer 2

aim is to restore blood supply (opposite can be fatal)

Question 3

haemorrhagic stroke

Answer 3

stop blood supply to brain (opposite can be fatal)

Question 4

CT scans

Answer 4

computerised tomography (takes images from various angles)

• ischaemic strokes look the same as normal brain until 48h after
• ventricles reduce in size
• swelling due to inflammation
• very good at identifying haemorrhages
• appear as white marks
• often first scans used as they are quick and easy
• if there are no white marks then haemorrhage can be rules out

Question 5

MRI

Answer 5

• happens later down the line as it takes longer
• much more sensitive to ischaemic strokes
• shows restricted blood flow

Question 6

zones of injury for ischaemic stroke

Answer 6

• ischaemic core (closest region to the supply of the artery thats been blocked)
  > severe ischaemia in this area (lack of blood flow)
  > 20% of normal blood flow (death early in cells - necrosis)
  > necrosis impossible to treat as cells have died within minutes
• ischaemic penumbra (surrounding the ischaemic core)
  > area that treatment tried to help
  > if patients are not seen quickly, this area increases in size, damaging more cells (cells will die within hours)
  > blood supply from nearby arteries

Question 7

treatment: ischaemic stroke

Answer 7

• ASPRIN (used to prevent blood clots from occurring)
• Tissue Plasminogen Activator (TPA) - pharmacological only treatment (thrombolytics)
• mechanical embolus removal in cerebral ischaemia (MERCI retriever)
• suction removal

Question 8

Tissue Plasminogen Activator (TPA)

Answer 8

Activates a component in the blood called PLASMINOGEN, which converts PLASMIN, breaking down blood clot (need to be given 3-4h after stroke)

• limited therapeutic time window
• risk of haemorrhages (breaks down clots which have weakened arteries
• have to consider other health issues and medication

Question 9

Mechanical Embolus Removal in Cerebral Ischaemia (MERCI retriever)

Answer 9

• insert wire into artery above the clot
• sheath retracts and curled wire catches in clot
• this wire is then removed, removing clot

Question 10

Suction Removal

Answer 10

• tube inserted into artery, wire comes out of sheath
• wire pokes clot
• suction clears the debris

Question 11

treatment: intracerebral haemorrhage

Answer 11

• want to stop bleeding, managing the symptoms
• CT scan can locate the haemorrhage
• antihypertensives (reduce blood pressure)
• Aneurysm clipping
• Coil embolisation

Question 12

Antihypertensives

Answer 12

• reduce blood pressure
• build up of blood pressure might lead to further problems
• elevating head to reduce blood pressure
• pressure can be put on brainstem affecting HR and breathing
• can drill a hole in the back of the head to reduce pressure as last resort

Question 13

aneurysm clipping

Answer 13

• surgeon uses a clip to secure aneurysm so blood does not leak into brain

Question 14

coil embolisation

Answer 14

• tube is put into artery and out into aneurysm

- coiled wire pushed until the gap is blocked

Question 15

risk factors (modifiable)

Answer 15

• hypertension (high blood pressure)
• cardiac disease (irregular HB, clot can travel up brain)
• diabetes
• high cholesterol
• lifestyle (diet, smoking, alcohol, exercise)
• transient ischaemic attacks (TIA) (mini strokes are a warning, need to change)

Question 16

risk factors (non-modifiable)

Answer 16

• age (arteries become stiffer with age and more weakened)
• gender (women prior to menopause are less likely to have strokes - due to progestin)
• ethnicity (more common in ethnic minorities - due to lifestyle factors linked to diabetes and hypertension)
• family history

Question 17

hypertension

Answer 17

• pressure of blood increases, speed of blood movement increases
• when this reaches a smaller artery, pressure is amplified
• leads to thickening of artery walls, easier for clots to develop
• if blood flow is quick, repeated knocking into blood vessel corners can cause ballooning (weakening)
• balloon then bursts and bleeds into the brain (haemorrhage)

[affects both types of strokes]

Question 18

risk factors: working together

Answer 18

• glucose (from sugar) in the blood can damage walls
• tobacco works in the same way
• high cholesterol = sits in areas damaged by sugar and cholesterol
• blood clots form blockages where plaque was
• plaque can become detached and travel to brain