Name one similarity and one difference between a TIA and a stroke
Similarity: They both have the same symptoms with same pathophysiology
Difference: TIA lasts for less than 24 hours, stroke lasts for more than 24 hours. Duration of symptoms is determining difference
Two reasons why TIA does not cause permanent infarction
Reperfusion
- ) Embolus breaks up
- ) Collateral circulation
What is the risk of stroke in 5 years after a TIA
30%
What are the risk factors for TIA/Stroke
Primary: Age and Hypertension
Secondary: Smoking, diabetes, hyperlipidemia, atrial fib, CAD, family history, previous stroke/TIA, and carotid bruits
What are risk factors for TIA/Stroke in young people
- ) Oral contraceptives
- ) Hypercoaguble state (Protein C and S deficiency, antiphospholipid antibody syndrome)
- ) vasoconstrictive drug use (cocaine, amphetamines)
- ) Polycythemia vera
- ) Sickle Cell Disease
Which one is more common: Embolism or Thrombus
Embolism
What are the four main sources of embolic strokes
- ) Heart (most common) - afib
- ) Internal Carotid Artery
- ) Aorta
- ) Paradoxical (from peripheral veins through ASD, patent foramen ovale, or pulmonary AV fistula)
What are common places of thrombus, hence thrombotic strokes
- ) Large arteries (i.e. birfurciation of common carotid)
2. ) Middle cerebral artery (MCA)
Which sized vessels does lacunar stroke affect, and what are the common areas
Small vessels
Subcortical regions - Basal ganglia, thalamus, internal capsule, brainstem
Two risk factors of lacunar stroke
- ) HTN (main)
2. ) Diabetes
The source of an embolic stroke is evaluated by three things
- ) Echo
- ) Carotid dopplers
- ) ECG, holter monitoring
Pathophysiology of lacunar strokes
THICKENING of vessel wall
Common places of lacunar stroke:
- ) Small branches off MCA
- ) Circle of Willis arteriies
- ) Basilar and vertebral arteries
Clinical feature of thrombotic stroke
Symptoms rapid or stepwise, with classic awakening from sleep with neurologic deficits
If embolism went to MCA, what would you see clinically
- ) Contralateral hemiparesis and hemisensory loss
- ) Aphasia (if dominant hemisphere)
- ) Apraxia, contralateral body neglect, confusion (if nondominant)
Four major focal clinical features of lacunar stroke
- ) Pure motor (internal capsule)
- ) Pure sensory (Thalamus)
- ) Ataxic hemiparesis - incordination ipsilaterally
- ) Clumsy hand dysarthria
Five modalities ordered to diagnose stroke
- ) CT Scan w/o contrast - determines if intracerebral hemorrhage is present
- ) MRI - more sensitive, not in emergency
- ) ECG - Acute MI or Afib
- ) Carotid duplex - carotid stenosis
- ) MRA - definitive for stenosis and aneurysms - carotids, vertebro basilar circulation, circle of willis, ACA, PCA, MCA
Three complications of stroke
- ) Cerebral edema 1 to 2 days causing mass effect
- ) Hemorrhage into infarction
- ) Seizure
How to treat cerebral edema secondary to stroke
Hyperventilation and mannitol
What to use for treatment of acute stroke in ED
Supportive treatment and t-PA therapy within 3 hours
Contraindications to TPA due to risk of hemorrhagic transformation
If time of stroke unknown If more than 3 hours have passed Uncontrolled HTN Bleeding disorder Anticoagulation Recent trauma or surgery
When to give TPA and when to give aspirin in acute treatment of stroke
TPA: Within 3 hours
Aspirin: After 3 hours (do not give both)
If aspirin not tolerated - clopidogrel, clopidogrel not tolerated - ticlopidine
Do not give heparin or warfarin in acute stroke
The three conditions in which you are allowed to give BP medications during acute stroke
- ) BP above 220/120
- ) Acute MI, aortic dissection, severe heart failure, hypertensive encephalopathy
- ) Thrombolytic therapy already given
When is carotid endarterectomy indicated
When patients are symptomatic with carotid artery stenosis of over 70%. For asymptomatic, give aspirin
Prevention of strokes in both embolic and thrombotic disease
Aspirin and control of atherosclerotic risk factors
Prevention of lacunar strokes
Control hypertension
Most common cause of intracerebral hemorrhage
HTN (sudden increase - 50 to 60%) that ruptures small vessels in brain parenchyma
Four minor causes of intracerebral hemorrhage
- ) Amyloid angiography
- ) Anticoagulant/antithrombolytic use
- ) Brain tumors
- ) AV malformations
Three locations of intracerebral hemorrhage
Basal Ganglia (65%)Pons (10%)Cerebellum (10%)
Four clinical features of intracerebral hemorrhage
- ) Abrupt onset of focal deficit worsening over 30 to 90 minutes
- ) Altered level of consciousness
- ) Headache, vomiting
- ) Signs of increased ICP
Diagnosis of intracerebral hemorrhage
CT scan (95%) with coagulation panel and platelets
Six complications of intracerebral hemorrhage
Increased ICP Seizures Rebleeding Vasospasm Hydrocephalus SIADH
Treatment of acute intracerebral hemorrhage
Step 1: ICU admission
Step 2: ABC’s due to altered mental status
Step 3: BP reduction gradually - prevents hypotension (BP > 160 to 180/105) - nitroprusside
Step 4: Mannitol and diuretics only if ICP elevated
Step 5: Surgical evacuation of hematomas if they exist
Should steroids be given in intracerebral hemorrhage
No
Two major categories of hemorrhagic stroke
- ) Intracerebral hemorrhage - bleed into parenchyma
2. ) Subarachnoid hemorrhage - bleeding into CSF
Three different pupillary findings in intracerebral hemorrhage depending on location
Pons - pinpoint pupils
Thalamus - poorly reactive pupils
Putamen - dilated pupils
Common location of subarachnoid hemorrhage
Saccular aneurysms - bifurcations of arteries at circle of willis
Three causes of subarachnoid hemorrhage
- ) Ruptured berry aneurysm - most common and most dangerous
- ) Trauma
- ) AV malformation
Clinical features of subarachnoid hemorrhage
Worst headache of life, with loss of consciousness, vomiting, and meningeal irritation with photophobia and retinal hemorrhages
Two diagnostic modalities of subarachnoid hemorrhage
- ) Noncontrast CT
2. ) Lumbar puncture if CT scan is negative - shows blood and xanthochromia - gold standard
After diagnosis of subarachnoid hemorrhage, what test should be ordered to confirm diagnosis
Cerebral angiogram
Complications of subarachnoid hemorrhage
- ) Rerupture
- ) Vasospasm
- ) Communicating hydrocephalus
- ) Seizures
- ) SIADH
Surgical treatment options of subarachnoid hemorrhage
Berry aneurysms treated surgically
Medical treatment of subarachnoid hemorrhage
Bed rest in quiet room, stool softeners to avoid straining, analgesis for headache, IV fluids for hydration, control HTN by BP lowering gradual, calcium channel blocker (nifedipine) for vasospasm
What is a heat stroke and what is required to make the diagnosis
Thermoregulatory problem - hyperthermia > 40.5C
How do patients with heat stroke present clinically
Acute confusion, tachycardia, coagulopathic bleed, hypotension
What is a complication of heat stroke
Rhabdomyolosis
What is wallenberg’s syndrome and what area of the brain does it affect
Occlusion of PICA or vertebral artery, affecting lateral medulla
What are the symptoms of wallenberg syndrome, and what is spared?
- ) Pain/temp loss over ipsilateral face/contralateral body
- ) Vestibulocereballar impairment
- ) Horners syndrome
Spared: Motor function
What is the diagnostic modality of choice for wallenberg syndrome
MRI
What is the difference in symptoms between intracerebral hemorrhage of cerebellum, thalamus, and pons
Cerebellum - Occipal lobe affected and gait disturbed
Thalamus - pupils do not react, eyes deviate toward lesion
Pons - pinpoint pupils, paraplegia then deep coma within minutes