Download The Unconscious Patient and Stroke

Stroke
Andy Ritson
Definition
• Focal neurological deficit of cerebrovascular
origin lasting >24 hours
• <24 hours = TIA
• Two types:
– Ischaemic
– Haemorrhagic
Ischaemic stroke
Pathophysiology
• Usually thrombotic embolus
• Origins:
– Heart (AF, MI)
– Carotids (atherosclerosis)
• Lodges distally occluding blood supply and
hence ↓O2 delivery to cerebral tissue
Ischaemic Cascade
• Failure of ATP dependant Na+/K+ pump –
depolarisation
• Glutamate toxicity
• Ca2+ influx into cells
• Initiating wide spread destructive effects
• Progressive infarction
Risk Factors
• Atherosclerosis:
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Smoking
Diabetes
Hypercholesterolaemia
Age
SE Asian heritage
• Thrombosis:
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Oral Contraceptive Pill
Polycythaemia
Thrombophilia
Vasculitis
• Cardiac:
- MI
- AF
- Valvular heart disease
- Previous Stroke / TIA
Clinical Picture
• Related to neuroanatomy:
Classification
Partial Anterior Total Anterior
Posterior
Lacunar
Signs
2 of the
following:
motor or
sensory deficit;
higher cortical
dysfunction,
hemianopia
Motor or
sensory deficit,
higher cortical
dysfunction
and
hemianopia
Isolated
Motory or
hemianopia,
sensory deficit
brainstem signs only
and cerebellar
ataxia
Arteries
affected
Ant. or middle
cerebral
Ant. or middle
cerebral
Post. cerebral,
basillar or
vertebral
Any deep
penetrating
artery
Higher cortical functions: Speech disturbances and visual-spatial disturbances.
Brainstem signs: Heart rate, blood pressure, breathing, swallowing, digestion, eye
movements, speech and body movement.
Cerebellar signs: nystagmus, truncal ataxia, co-ordination problems etc
ACUTE MANAGEMENT
• Airway
– Protected
– Swallowing?
• Breathing
– Adequate on air?
• Circulation
– Fluid replacement if BP ↓
– Do not routinely treat hypertension
• Disablility
– GCS
– Pupils
• Exposure
– Sustained other injuries with fall?
– Concomitant pathologies?
• GLUCOSE!
Investigations:
• CT Scan:
– Rule out HAEMORRHAGE
– Exclude tumour
– Evidence of early ischaemic changes
• Bloods – FBC, U+E, Glucose, Coagulation,
ESR
• Cardiac
– ECG
– Echo
– Carotid doppler US
• CXR – heart size, lung pathology, tumours
Thrombolysis
• Administered <4.5hrs of symptom onset
• Recombinant tissue Plasminogen Activator
(rtPA) = “alteplase”
• Binds to fibrin and activates plasminogen →
cleaves fibrin → degrades thrombus
• Also give Aspirin 300mg
Contraindications
•
Extremes of age (>80 or <18)
•
Previous severe disability / terminal illness
•
Hx ICH / neoplasm or AV malformation
•
Stroke / prev head trauma (3/12)
•
Platelets ↓or INR > 1.5
•
Pregnancy / Recent Childbirth (2 weeks)
•
Recent MI (1 month)
•
Active Bleeding / Acute Trauma
•
Major Surgery (2 weeks)
Complications
• Dysphagia
– Malnutrition / Medications
– Aspiration pneumonia
• Immobility
– Muscle wasting and contractures
– Pressure sores → ulceration → infection
– Falls
– Osteoporosis
• Incontinence
– Skin integrity
– Retention of Urine
– Catheterisation → UTI
• Epilepsy
• Depression
• Death
Secondary Prevention
• Antiplatelet
– Aspirin 300mg (2/52) then 75mg
• Statin
• BP (aggressive if DM)
• Carotid Endarterectomy
• Lifestyle
Case 1
An 81 year old woman is found collapsed on
her bedroom floor by the sheltered housing
warden the day after a trip to her bingo. A CT
scan of the brain reveals an area of ischaemia
in the left parietal cortex, consistent with a
recent cerebral infarct. She is badly bruised
and has an obvious weakness on the right side
of her body. She is confused and her speech
sounds slurred.
• An 81 year old woman is found collapsed on
her bedroom floor by the sheltered housing
warden the day after a trip to her bingo. A CT
scan of the brain reveals an area of ischaemia
in the left parietal cortex, consistent with a
recent cerebral infarct. She is badly bruised
and has an obvious weakness on the right side
of her body. She is confused and her speech
sounds slurred.
a. What is the definition of a stroke?
A rapidly developing focal neurological deficit
of vascular origin lasting over 24 hours or
causing death
b. Suggest 4 risk factors for stroke?
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Hypertension
Atrial fibrillation
Diabetes mellitus
Smoking
Previous TIA/stroke
Increasing Age
Oral contraceptive pill use
Coagulopathy
Sedentary lifestyle
Hypercholesterolaemia
Raised haematocrit
Cocaine use
Male
Asian descent
c. The CT scan of the brain showed an area of ischaemia. Explain the
pathogenesis of this cause of stroke.
• Narrowing of the supplying blood vessels (thrombus, embolus)
causes reduced blood flow (and thus oxygen and glucose) to an
area of the brain.
• There is a central area of necrosis surrounded by a penumbra that
may be salvageable if blood supply is re-established.
• There is an initiation of the ischaemic cascade that causes
inflammation and oedema that results in tissue damage.
• This leads to glutamate toxicity and cell membrane permeability
changes thus activating destructive enzymes.
d. Given this lady’s symptoms, which is the
most likely artery to have been affected by
this stroke?
• Left Middle Cerebral Artery
e. List 4 significant non-neurological complications
of stroke.
• Aspiration pneumonia
• DVT/PE due to immobility
• Communication difficulties due to dysphasia and
dysarthria
• Depression
• Bed sores due to immobility
• Urinary incontinence
f. This patient shows slow improvement over
the next three months. Outline 2
management options that the OT would be
able to help with in cases like this.
• Home assessment and adaptations where
appropriate
• Physical and cognitive deficit screen and
provision of aids where needed
Past paper 2
While working as a FY1 on a medical ward you
are asked to assess Mrs FK, a 75 year old woman,
who was admitted to hospital one week
previously with a sudden onset of weakness in
the right arm and leg. On examination you
confirm the weakness and also find that the
muscle tone in the right arm and leg is increased.
Sensation is decreased on the right side.
Although she can talk, she sometimes has
difficulty finding the words she wants.
While working as a FY1 on a medical ward you
are asked to assess Mrs FK, a 75 year old woman,
who was admitted to hospital one week
previously with a sudden onset of weakness in
the right arm and leg. On examination you
confirm the weakness and also find that the
muscle tone in the right arm and leg is increased.
Sensation is decreased on the right side.
Although she can talk, she sometimes has
difficulty finding the words she wants.
a. What changes do you expect in the tendon reflexes on the right side?
Hyper-reflexive (brisk)
b. What is the mechanism of this alteration to the reflexes?
Loss of descending inhibitory input to the reflex arc resulting in an uninhibited
reflex response.
c. What do you expect the right plantar reflex to be?
Up going
d. Which cranial nerve is the one most likely to be affected?
Trigeminal (CN 5)
e. What visual field abnormality might you expect to find on examination?
Homonymous hemianopia
Over the next 24 hours the patient’s condition
deteriorates. A CT scan confirms an infarct in
the left middle cerebral artery territory. Her
husband calls you aside and asks you to write
in her notes that she should not be
resuscitated if she stops breathing.
f. Which 2 articles of the Human Rights Act are most applicable when
considering these issues?
Article 2 – right to life
Article 3 – protection from mistreatment
e. Having established the diagnosis, what three issues do you need to take
into consideration
before writing a “Do Not Resuscitate” order?
• Has the DNR order been discussed with the patient and family
• Does the patient have capacity to make the decision
• Would resuscitation likely to be successful and beneficial for the patient
Haemorrhagic strokes
Pathology
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Aneurysms
Arteriovenous formation
Trauma
Blood coagulation disorders
Vessel erosion by tumours
Types
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Extradural
Subdural
Intracerebral
Subarachnoid
Case 1
• 18 year old male presents to ED after
being hit on the head with a bottle 3 hours
previously
What would you do?
– ABCDE
– History: slightly drowsy after injury, but has
resolved, no LoC
– O/E: GCS 15, no focal neurology, large
parietal haematoma
Deteriorates after another hour
Extradural
• Laceration of MMA by fracture of temporal
or parietal bones
• Features:
– Lucid interval followed by GCS
– Deterioration is due to ICP
– May get UMN signs
• Management:
– ABCDE  CT  Surgeons
Case 2
• 87 year old demented female has fallen
out of bed that morning
What would you do?
– ABCDE
– History: headache, “more confused”, AF,
vomited
– O/E: GCS 13, drowsy, dysphasic
Therefore:
- Bloods and CT
Acute Subdural
• Shearing of veins crossing the subdural
space
• Associations:
– Trauma, alcohol, anticoagulation
• Features:
– Progressively GCS
– Signs of ICP
• Management:
– ABCDE  CT  Surgeons
Chronic Subdural
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Similar to ASDH, but insidious
Fluctuating consciousness
Personality change
Sleepiness
Unsteadiness
Features of raised ICP
Almost always very old or very young
Case 3
• 48 year old male presents to the ED after
a night out
• What would you do?
– ABCDE
– History: friends says he collapsed, had been
using cocaine
– O/E: GCS 12, Babinski positive on the right,
right hemi-paresis
– CT and bloods
Intra-cerebral
• Rupture of small intracerebral vessels:
– Spontaneous = “haemorrhagic stroke”
• Features:
– Neurology dependent on location
– ICP (blood + oedema)
• Associations:
– Hypertension
– AVM, bleeding disorders, drugs
• Management:
– ABCDE  CT  ?Surgeons
Case 4
• 48 year old female presents with “worst
headache of my life”
• What would you do?
– ABCDE
– History: instantaneous severe occipital
headache, vomited 3 times, has polycystic
kidneys
– O/E: GCS 12, Kernig’s positive, hypertensive,
pyrexial
Subarachnoid
• 80% ruptured aneurysm, 5% AVM
• Associations:
– Smoking, alcohol, hypertension
– Polycystic kidney disease, family history,
bleeding disorders
• Features:
– Thunderclap headache, vomiting, GCS, neck
stiffness, pyrexia, Kernig’s sign, BP
• Management:
– ABCDE  CT  Nimodipine  Surgeons