brain attack! is it a stroke? dr richard i lindley consultant geriatrician part-time senior lecturer...
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Brain attack! Is it a Stroke?
Dr Richard I Lindley
Consultant Geriatrician
Part-time Senior Lecturer
How accurate is the diagnosis of stroke typically made by the
doctor in the Emergency Room?
• 50%
• 60%
• 70%
• 80%
• 90%
• 95%
How accurate is the diagnosis of stroke typically made by the
doctor in the Emergency Room?
• 50%
• 60%
• 70%
• 80%
• 90%
• 95%
1991 to 1992 WGH Series
350 patients referred to stroke team
54 did not have stroke
85% accuracy
Mimics
3% Tumour
1% Seizures
1% Previous stroke and new intercurrent illness
Other mimics
• Migraine• TIA• Wernicke’s
encephalopathy• Myelopathy• Hyponatraemia• Labyrinthitis• Septicaemia
• Delirium• Hysteria• Spinal cord stroke• Chest pain!• Lung cancer• Phenytoin toxicity• Spinal cord
compression
Dr Peter Hand 2000-2001
Assessed 350 patients
(92% admitted through ARU)
18.6% were stroke mimics
4% Seizure
3% Tumour
2% Sepsis
2% Toxic/metabolic
Stroke Mimics 2000
• Syncope• Delirium• Vestibular dysfunction• Mononeuropathy• Medically unexplained• Dementia• Migraine
• Parkinson’s Disease• Spinal Cord Lesion• SAH• Transient global
amnesia
What are the key components to identify definite stroke from
stroke mimic?
Need to reflect on the definition of stroke and TIA
Stroke
A clinical syndrome characterized by rapidly developing clinical symptoms and/or signs of focal, and at times global (applied to patients in deep coma and those with subarachnoid haemorrhage), loss of cerebral function, with symptoms lasting more than 24 hours, or leading to death, with no apparent cause other than that of vascular origin.
Hatano 1976
Transient ischaemic attack (TIA)
A clinical syndrome characterized by an acute loss of focal cerebral or monocular function with symptoms lasting less than 24 hours and which is thought to be due to inadequate cerebral or ocular blood supply as a result of low blood flow, arterial thrombosis or embolism associated with diseases of the arteries, heart or blood.
Hankey & Warlow 1994
Advantages of stroke and TIA definitions
•Allows stroke incidence to be compared around the world (epidemiology)
•Ensures a common language (clinicians)
•Helps clinician identify certain non-stroke pathology (guides differential diagnosis)
Disadvantages of definitions of stroke and TIA
•The invention of CT scanning (1970’s) emphasised the heterogeneity of stroke (syndrome can be due to cerebral infarction, cerebral haemorrhage or subarachnoid haemorrhage)
•In the era of “time is brain” what do we call an attack, which has not resolved, assessed within 24 hours of onset?
•They are based on clinical assessment and in the era of modern technology have we not got a better objective method of assessment?
TIA: Ischaemic stroke continuum
Anything which causes a TIA, will, if prolonged cause a stroke.
Quantitatively, not qualitatively, different
Duration of attack and percentage of patients with a
relevant infarct on CT
0
5
10
15
20
25
30
35
40
45
50
% of patients withinfarct on CT scan
1-30
min
31-6
0min
1-4
hou
rs
5-24
hou
rs
1-7
day
s
1-6
wee
ks
Per
sist
ing
Duration of symptoms
Koudstaal et al 1992 JNNP;55:95
The History
Strokes are common in old people with vascular disease
How old are they?
If young (<60 years old) have they premature vascular disease or have they an unusual cause of stroke (e.g. a right to left shunt from patent foramen ovale)
Have they got vascular disease?
Previous heart attacks, diabetes, hypertension, previous stroke or TIA, high cholesterol?
Were they previously well?
The History: exclude mimics
• Transient loss of consciousness suggests seizure or cardiac disease
• Dementia makes all diagnoses difficult
• Have you got a source of history from another person?
The Examination
• Have they got signs of vascular disease (e.g. lost pulses, heart murmurs, carotid bruits, hypertension)?
• Have they got focal neurological deficits?
• Have they got sustained global neurological deficit e.g. coma?
Acute brain attack
Exclude: fits/migraine
Hypo-hyperglycaemia
Other metabolic causes
CT ScanExclude tumour /structural lesion Non-stroke pathology
Confirmed ischaemic brain attack
PICH, SAH, Subdural
Exclude:
intracranial bleed
Stroke IS an Emergency!
Stroke is a “Brain Attack”
Brain Attack is an emergency
“Time is Brain”
The Brain Attack Team: the need for investment• Ambulance Service
• Casualty Dept
• Radiology/Neuroradiology/Physicians/Radiographers
• Acute stroke units
• Pharmacy & Laboratory
• Large RCT’s
• Admissions
• Administration
• Public Relations/CommunityEducation
AMBULANCEAMBULANCE
Confirmed ischaemic brain attack
TIAAre the symptoms/signs resolving rapidly?
Yes
No
Are the symptoms/signs disabling?No
Treat like TIA
Yes
Consider more intensive treatment
Summary
Definitions of TIA and Stroke a bit out of date
The new paradigm of Brain Attack may be useful
There are many non-cerebrovascular causes of brain attack
Question 1
Mrs X 78 years old
Perfectly well until day of presentation
Wife noticed that he was “not himself”
Collapsed and brought into A&E dept
Was noted to be aphasic (language problem) and right sided weakness
Then had an epileptic fit
CT scan
CT scan
Showed a problem in the appropriate hemisphere
Interpreted as being early ischaemia
Admitted to stroke unit
Developed status epilepticus
Is this a stroke?
CT scan reviewed
Odd swollen appearance
Possibly herpes simplex encephalitis
Despite anticonvulsants, and anti-viral therapy, patient died.
Post mortem showed...
Post mortem examination
Gliomatosis cerebri
Brain tumour cells found throughout entire brain
Did eventual tumour mass cause electrical instability?
Lesson
A common mimic of “stroke” in emergency medicine is brain tumour (a cause of about 3-5% of all initial “stroke” diagnoses).
Clues: CT scan appearance very atypical for stroke
Status epilepticus rare after acute stroke
Question 2: Mr Y
A 72 year old lady with known bladder cancer (transitional cell carcinoma) presents with mild left sided weakness.
CT scan
What’s the diagnosis?
What’s the diagnosis?
Right frontal lesion is a primary intracerebral haemorrhage stroke
The left frontal lesion is an incidental meningioma
Lessons
Stroke affects older people and co-morbidity is common
About 10% of all stroke is due to primary intracerebral haemorrhage
Pathology of stroke can now be reliably established by CT scanning done within hours/days of the event
Cerebral infarction 80%
Primary intracerebral haemorrhage 10%
Subarachnoid haemorrhage 5%
Unknown 5%
Sudlow & Warlow 1997
Systematic review of world-wide incidence studies
Question 3
64 year old man was driving his car and he suddenly lost power in his right arm and leg
He had no headache
No loss of consciousness
Called for help and son brought him to casualty
No significant medical history
On examination
Looked well
Blood pressure 200/120 mmHg
Normal language
Slurred speech
Complete weakness affecting his right face, arm and leg
No hemianopia
Is this a stroke?
Yes! Due to a Lacunar Infarction
Question 4: 85 year old lady
Presents with a sudden onset of dizziness and headache
On examination she had nystagmus
Six hours after admission started to complain of worsening headache
24 hours later was unconscious
Is this a stroke?
Yes! A cerebellar
haemorrhage with acute
hydrocephalus
Question 5Mrs X 69 years old
Developed Right hemiparesis and aphasia during breakfast (9am)
Husband called GP and sent immediately to A & E department
Severe (0/5) right face, arm and leg weakness
Dyspraxia (disorganised movement of body)
Aphasic (no understanding or expression of language)
Is this a stroke?
Is this a stroke?
Yes! Dense MCA sign indicating thrombus in the left MCA