Stroke

Question 1

What is a cerebrovascular accident ?

Answer 1

Stroke

Types

ischaemic stroke - blockage of blood flow

Haemorrhagic stroke - burst blood vessel - blood spills out and pools in the brain interrupting blood flow and increase in pressure in the brain

Left side of the brain - controls right side

Right side of the brain controls left side.

• TIA - transient ischaemic attack - blood supply to brain temporarily interrupted.

Question 2

FAST acronym -Stroke

Answer 2

Facial drooping - one side

Arms - weakness or numbness in one arm (not able to lift both arms and keep it there)

Speech - slurred , not able to talk while awake, problems understanding

Time - call 999

Question 3

Management of Transient ischaemic attack.

Answer 3

Suspected TIA

1. Referral to specialist TIA unit for assessment and investigation.
2. Aspirin 300 mg daily immediately (unless contraindicated)
3. MRI to detect territory of ischaemia or haemorrhage
   
   • same days as assessment.
4. Secondary prevention of occlusive events :

Modified-release dipyridamole in combination with aspirin - FIRST OPTION

Modified-release dipyridamole without aspirin - (ONLY WHEN ASPIRIN USE IS CONTRAINDICTAED OR NOT TOLERATED)

• DO NOT OFFER CT SCAN TO SUSPECTED TIA PATIENTS -unless there is clinical suspicion of an alternative diagnosis that CT could detect.
• Everyone with TIA who after specialist assessment is considered as a candidate for carotid endarterectomy (REMOVE PLAQUE BUILD-UP IN CAROTID A. OF NECK)should have urgent carotid imaging.

Question 4

Management of Acute stroke ?

Answer 4

1. Non -enhanced CT scan immediately
2. Maintain a blood glucose concentration between 4 and 11 mmol/litre in people with acute stroke.
   * Provide optimal insulin therapy, which can be achieved by the use of intravenous insulin and glucose, to all adults with type 1 diabetes with threatened or actual stroke.
3. thrombectomy + intravenous thrombolysis as soon as possible and within 6 hours of symptom onset,
   
   • thrombolysis - clot busting drugs injected.
4. Aspirin 300mg (2 weeks after symptom onset) or other anti -platelet drug
   0 oral - no dysphagia
   0 rectally - rectally or enteral tune -if dysphagia present.

5.long-term antithrombotic treatment - after 2 weeks or before is discharged before 2 weeks.

• you would screen patient for dysphagia (common after stroke -impaired GAG REFLX) - too see they can eat normally to avoid poor nutrition etc.
  0 dysphagia can lead to aspiration of saliva and gastric contents and anything swallowed leading to pneumonia (infection inflames air sacs of lung)

Question 5

Acute stroke - middle cerebral infarct

Answer 5

Consider decompressive hemicraniectomy for middle cerebral artery infarction

• consider for following criteria

0 clinical deficits that suggest infarction in the territory of the middle cerebral artery, with a score above 15 on the NIHSS

0 decreased level of consciousness, with a score of 1 or more on item 1a of the NIHSS

0 signs on CT of an infarct of at least 50% of the middle cerebral artery territory:
with or without additional infarction in the territory of the anterior or posterior cerebral artery on the same side

or

0 with infarct volume greater than 145 cm3, as shown on diffusion-weighted MRI scan.

Question 6

Acute stroke - carotid stenosis

Answer 6

Have symptomatic carotid stenosis of 50% to 99% according to the NASCET criteria with symptoms of non-disabling stroke or TIA:

0 assessed and referred urgently for carotid endarterectomy

0 receive best medical treatment 
      - control of blood 
        pressure, 
      - antiplatelet agents,
      - cholesterol lowering 
        through diet and drugs, 
        lifestyle advice).

carotid stenosis of less than 50% according to the NASCET criteria, or less than 70% according to the ECST criteria with non-disabling stroke or TIA:

0 do not have surgery

0 receive best medical treatment

Question 7

Management of Haemorrhagic stroke

Answer 7

Medical management - with medicine

surgical - presence of hydrocephalus following primary intracerebral haemorrhage

Hydrocephalus - accumulation CSF in brain

intracerebral haemorrhage -
* if on warfarin give prothrombin complex concentrate + intravenous potassium to return blood clotting kevels to normal as soon as possible

0 blood pressure control 
rapid blood control 
      - if present within 6 
        hours of symptom 
        onset + systolic 
        pressure - 150 -220 
        mmHg 

      - if present after 6 
        hours of symptom 
        onset + systolic 
        pressure > 220 
        mmHg 

• Aim for a 130 -140mmHg within 1 hour of starting treatment.

Do not offer rapid blood pressure lowering to people who:

0 have an underlying structural cause (for example tumour, arteriovenous malformation or aneurysm)

0 have a score on the GCS of below 6

0 are going to have early neurosurgery to evacuate the haematoma

0 have a massive haematoma with a poor expected prognosis.

Question 8

Consequences of haematomas growth ?

Answer 8

haematoma growth ——> increase intracranial pressure ———> midline shift (displacement of brain)

Increased intracranial pressure causes :

• cushing’s triad
  0 increased BP
  0 Bradycardia
  0 irregular breathing

Lumbar puncture - contraindication ibn increased intracranial pressure.

Question 9

What is uncal herination ?

Answer 9

uncus (innermost part of temporal lobe moves down and compresses brain stem.

• compression of oculomotor nerve - nerve palsy

Question 10

What is external herniation ?

Answer 10

Transcalvarial - Brain leaves leaves skull through fracture or surgical site.

Question 11

What is Cingulate herniation ?

Answer 11

Subfalcine - Cingulate gyrus squeezes past falx cerebri
to the opposite side

• falx cerebri - separates left and right hemisphere.
• compress anterior cerebral artery -ischaemic stroke.

Question 12

What is central herniation ?

Answer 12

trans- tentorial - dicephalon and part of temporal lobe move down past tentorium

.- effects cerebrum -supratentorial

Question 13

What is upward cerebellar herniation ?

Answer 13

Cerebellum displaced upwards through notch in tentorium cerebelli

effects cerebellum - infratentorial

Question 14

What is downward cerebellar herniation ?

Answer 14

Tonsillar herination.

Cerebellum tonsil slips through magnum forearm.

Can compress nerves - responsible for breathing and cardiovascular function

Question 15

Dysphagia (abnormal gag reflex) and stroke - what is done about it ?

Answer 15

Enteral feeding - PEG tube - percutaneous endoscopic gastrostomy

or Nasogastric tube

Due to high risk of aspiration and poor nutrition.

Question 16

What is Myasthenia gravis ?

Answer 16

Myasthenia gravis- rare Autoimmune condition long-term condition characterized by: 
     0 presence of 
       acetylcholine receptor 
       antibodies 
     0 depletion of 
        acetylcholine 
       receptors. that causes 
       muscle weakness.

It most commonly affects the muscles that control:

    - eyes and eyelids, 
    - facial expressions, 
    - chewing, swallowing
    - speaking. But it can affect most parts of the body.

It can affect people of any age, typically starting in women under 40 and men over 60.

0 droopy eyelids
0 double vision
0 difficulty making facial expressions
0 problems chewing and 0 0 difficulty swallowing
0 slurred speech
0 weak arms, legs or neck
0 shortness of breath and occasionally serious breathing difficulties

The symptoms tend to get worse when you’re tired. Many people find they’re worse towards the end of the day, and better the next morning after getting some sleep.

*reflexes tend to be normal

Question 17

Test used to confirm myasthenia gravis ?

Answer 17

0 Ice-pack cooling test to affected eyelid - placing ice over the affected eyelid with a temporary resolution of myasthenia

* cold decreasing breakdown of acetylcholine by acetylcholinesterase at neuromuscular junction.   - Postitive test - improvement of ptosis (dropping eyelids ) - 80% positive rate

0 Acetylcholine receptor antibody titres - will have positive titres (majority)

0 edrophonium (or Tensilon) (Acetylcholinesterase inhibitor )test - USED LESS COMMONLY

• injection of a medication called edrophonium (trade name Tensilon) - boosts the signal between nerve and muscle.

Will temporarily improve muscle weakness (only a few mins)

• Side effect

Tends to slow down heart rate. Patient connected to heart monitor. Atropine used to minimise side effect.

0 Thyroid function tests - association with thyroid dysfunction so TFTs should be checked.

0 Electromyography (EMG)- technique for evaluating and recording the electrical activity produced by skeletal muscles

EEG OT INDICATED (ELECTOENEPHALOGRAM - electrical activity if brain)

Question 18

What is Myasthenia crisis ?

Answer 18

Myasthenic crisis is a complication of myasthenia gravis characterized by worsening of muscle weakness,

respiratory muscles get too weak;
     -to move enough air in 
      and out of the lungs
    - To clear bronchial 
      secretions.

0 Risk of sudden apnoea - cessation of breathing

Possible causes

• Chest sepsis is the commonest causative factor
• Pregnancy may precipitate a myasthenic crisis
• Tetracycline is a recognised precipitant

Question 19

Treatment of Myasthenia Gravis ?

Answer 19

Corticosteroids - supress immune system response

Thymectomy - surgical removal of thymus gland (if thymic mass present)

Azathioprine - immunosuppressant

Plasmapheresis - removal of abnormal antibodies and replacement with normal ones from donated blood.

Acetylcholinesterase inhibitor e.g. pyridostigmine

IV Immunoglobulins - decrease immune systems attack on nervous system

Question 20

Myasthenia Gravis - cholinergic crisis ?

Answer 20

Overtreatment with anticholinesterase inhibitor can cause cholinergic crisis.

muscarinic and nicotinic toxicity

• increase in perspiration,
• lacrimation,
• salivation
• pulmonary secretions,
• nausea, vomiting,
• diarrhoea,
• bradycardia,
• fasciculations.

Acetycholine -neurotransmitter - contracts SM, dilate BV , Increase bodily secretions , slow heart rate.

Question 21

What is Bell’s Palsy ?

Answer 21

an idiopathic facial nerve palsy - most common cause of facial nerve palsy.

-viral aetiology is likely -herpes simplex virus

Symptoms

• paralysis affects the entire half of the face, including the forehead (very small percentage have it on both sides)
• Rapid onset of features
• Preceding ear pain

0 drooping of mouth
0drooling
0 inability to close eye - causing dryness
0 excessive tearing in one eye
0 intolerance to loud noise
0facial pain /abnormal sensation 
0 altered taste 

• • Does not affect arms , limbs like in TIA/stroke
• MOST PEOPLE WITH PARALYSIS MAKE A FULL RECOVERY- RAPIDLY- WITH OR WITHOUT TREATMENT IN A FEW WEEKS - WITHIN 6 MONTHS RECOVER SOME OR ALL FACIAL FUNCTION#
• Axonal degeneration is a recognised complication

Question 22

Function of facial nerve ?

Answer 22

Control of facial muscle - facial expression

• eye blinking / closing
• sends nerve impulses to :
  0 tear glands

0 salivary glands (not parotid)

0 muscles of the small bone in middle ear - paralysis of stapedius (can cause hyperacusis - sensitivity to loud sounds)- if facial nerve damaged.

0 Sends impulses to anterior 2/3rds of tongue for taste sensation (via chorda tympani - passes through middle ear - can get damaged by ear conditions)

Question 23

Causes of facial nerve palsy?

Answer 23

0 Bell’s Palsy - most common

0 Ramsay - Hunt syndrome -
* shingles outbreaks affects the facial nerve(inflammed and irritated). Caused by Herpes Zoster.

Symptoms

Vesicular rash in or on the ear - IMPORTANT

A rash or blisters in or around the ear, scalp or hair line. The blisters may also appear inside the mouth.
The rash/blisters are often painful with a generalised sensation of burning over the affected area.

0 Weakness on the affected side of your face which causes the facial muscles to droop.

0 Difficulty closing the eye or blinking on the affected side.
Altered taste on the affected half of the tongue.

0 Loss of facial expression on the affected side.

0 Difficulty eating, drinking and speaking as a result of weakness in the lip and cheek on the affected side.

0 Ear, face or head pain.

0 Hearing loss on the affected side - sensorineural

0Dizziness/vertigo

0 Tinnitis (ringing in the ear) on the affected side.

Question 24

Treatment of Bell’s palsy ?

Answer 24

• Short course of steroids
• Anti viral therapy

Eye protection - Encourage eyelid closure either by hand or using tape at night

• Eye protection is important. Partial lid suturing can be used in cases with severe associated ectropion (eyelid turns outward - inner surface exposed -prone to irritation).