Neurology (Stroke & TIA)
What are the contraindications to using thrombolysis?
1) Elevated BP that cannot be controlled 2) Bleeding disorder 3) Stroke or head trauma in the prior 3 months 4) Prior history of intracranial hemorrhage 5) Major surgery in the past 14 days 6) GI or GU bleeding in the previous 21 days 7) MI in the prior 3 months 8) LP within the past 7 days 9) Evidence of hemorrhage on head CT 10) Symptoms suggestive of SAH, even if CT is normal 11) Pregnancy or lactation 12) Active bleeding or acute trauma/fracture
What is herniation?
#1) Midline shift #2) Downward displacement of the cranium #3) Uncus and hippocampus herniate into the tentorial notch #4) Cerebellar tonsils herniate through the foramen magnum = DEATH
What should I do with Patients who have had a suspected TIA and require urgent evaluation?
1) Determine type and location of TIA 2) Non-contrast CT scan 3) Duplex ultrasound and transcranial doppler 4) MRI/MRA can demonstrate circulation, evaluate for stenosis 5) ECG and transesophageal echocardiography 6) Hospitalization may expedite workup 7) Consider hospitalization for patient with first TIA in the past 24-48 hours, as well as those with symptoms that are worsening or last for more than one hour, if there is a known carotid artery stenosis, afib, or hypercoagulable state
What is a TIA (transient ischemic attack)?
1) Brief episode of neurological dysfunction 2) Resulting from decreased perfusion 3) Impeding stroke!!! 4) Symptoms resolve in less than an hour
What are the sources of an embolus that causes a stroke?
1) Cardiac - Atrial fibrillation - Valvular Disease (endocarditis) 2) Carotid - Atheroma 3) Aortic atheroma 4) Unknown
What are the symptoms of an intercerabral hemorrhage?
1) Confined to the tissues that contain bleeding 2) Evolve over minutes-hours 3) Do NOT BEGIN ABRUPTLY 4) ARE NOT MAXIMAL AT ONSET 5) Symptoms are progressive
What is the PRIMARY prevention of stroke and TIA?
1) HTN --> Control it baby! If you don't its badness 2) Other cardiac risk factors - Risk of stroke is 50% higher in smokers than in nonsmokers 3) Aspirin 4) Consider anticoagulation for patients with A-fibrillation
What are the causes of intercerbral hemorrhage?
1) Hypertension 2) Trauma 3) Illicit drug use (cocaine and/or methamph.)
Most guidelines recommend that BP NOT be treated acutely in the patient with ISCHEMIC stroke unless SBP over
220mgHg and/or DBP over 120mmHg
Which occurs most, ischemic or hemorrhagic stroke?
80% Ischemic Stokes : 20% Hemorrhagic
What is an Aneurysm?
A bulge (dilation) in the wall of an artery, usually the aorta.
What is the most IMPORTANT risk factor for stroke?
Arterial Hypertension!!!! (Systolic and diastolic BP are independent risk factors)
This is defined as: 1) Congenital Arterial-Venous connections w/o a capillary bed in-between 2) High flow of blood 3) Not completely normal blood vessels
Arteriole-Venous Malformations (AVM)
If a stroke patient is not a candidate for thrombolytics, what shoule be prescribed?
Aspirin, after exclusion of hemorrhage on CT.
What is used in the evaluation "screening" of suspected stenosis of the intracranial internal carotid artery, middle cerebral artery, or basilar artery.
Carotid Doppler
This is hemorrhage within the brain substance
Cerebral hemorrhage
**What is the s "gold standard" for AVM or SAH but has a 1% risk of stroke during procedure.**?
Conventional angiography
Which is better in Atrial Fibrillation, Coumadin or Aspirin?
Coumadin
This is caused by include bleeding within the brain (intracerebral hemorrhage) and bleeding between the inner and outer layers of the tissue covering the brain (subarachnoid hemorrhage).
Hemorrhagic stroke
If by chance the BP gets over 220/120, what should be prescribed?
Labetolol (Beta Blocker) Works by relaxing blood vessels and slowing heart rate to improve blood flow and decrease blood pressure.
What is another name for Small Vessel Disease ?
Lacunar Infarcts
How does hemorrhagic stroke look on a non-contrast CT?
Looks bright/white - should show up earlier
How does Ischemic stroke look on non-contrast CT?
Looks dark - may be normal in first 24 hours
What is much better than CT for detecting brainstem and cerebellar strokes?
MRI
I say again, what is the threshold in ISCHEMIC stroke?
220/120
What is another name for hypoperfusion?
Anoxic Brain injury
What arteries are affected in small vessel disease?
****Small (.5-1.5 mm) arteries from**** 2) Distal vertebral artery 3) Basilar artery 4) Middle cerebral artery stem
What large vessels are affected in ischemic stroke??
***Large vessel disease (inside & outside the head)*** 1) Circle of Willis 2) Carotids 3) Vertebral blood vessels
Manage the Temperature! But how?
***Liberal use of antipyretics*** - Decreased stress - Watch for worsening disease - Think edema--> Increased ICP o Neuro checks q2 hrs o Vitals q2 hrs
Why should I be permissive with the Blood pressure in ISCEHMIC stroke?
- Ischemic stroke causes decreased blood flow distal to obstruction, with blood flow in the distal blood vessels dependent upon systemic BP - Elevated BP may be a chronic condition or may be a response to decreased cerebral perfusion
What is the treatment of a patient with a TIA?
1) * Consider thrombolytic therapy 2) Antiplatelet therapy - Aspirin reduces risk of subsequent TIAs or stroke - 325mg po qD - Ticlopidine 250mg po BID may be more effective than aspirin in preventing stroke but it's a lot more expensive - Clopidogrel (Plavix) 75mg po qD is another antiplatelet option. 3) Carotid endarterectomy (may be indicated for patients with 70% or more carotid stenosis (of course, only works for patients with stenosis of common or internal carotid artery, not in treatment of vertebrobasilar TIAs) 4) Angioplasty or stenting? ****Either way, antiplatelet agents should be started ****
What is an emboli?
1) A particle from elsewhere that lands in the brain 2) Variable clinical picture
What are some other risk factors for stroke?
1) A. Fib 2) Smoking 3) Lipids 4) Diabetes 5) Previous TIA 6) 1/3 will have a full stroke in 5 years Age
What are the three most predictive examination findings for acute stroke (Ischemic)?
1) Asymmetric facial paresis 2) Arm drift/weakness 3) Abnormal speech (dysarthria) **Note** Ischemia is dark (black)
What are the causes of large vessel disease?
1) Atherosclerosis 2) Vasoconstriction 3) Arterial Dissection
What are the two mechanisms of action for a stroke?
1) Bleeding - Hemorrhage 2) Lack of blood flow - Thrombotic - Embolic
Describe what happens during an aneurysm
1) Bleeding typically short - Arterial spasm common - Rebleeding very common o And fatal 2) Clot formation causes vasospasm 3) Distal hypoperfusion - Results in Ischemic damage
What happens when there is Arterial bleeding into the CSF?
1) Blood is NOXIOUS to the Brain 2) Blood spreads throughout the CNS 3) Causes elevated ICP -->Coma-->Death
What should be prescribed if a patient with a Intracerebral hemorrhage or a subarachnoid hemorrhage has a Systolic BP over 160?
1) IV nitroprusside (Nitropress) - A vasodilator that works by relaxing the muscles in your blood vessels to help them dilate (widen). This lowers blood pressure and allows blood to flow more easily through your veins and arteries. 2) Nicardipineis (Cardene) - used to treat high blood pressure. It relaxes your blood vessels so your heart does not have to pump as hard. It also increases the supply of blood and oxygen to the heart to control chest pain (angina). 3) Labetalol
What are the three goals of managing a stroke?
1) Identifiy the cause of neurologic deficit - IF NOT stroke, then what? Can it be treated - Said another way, not all neurologic deficits are from stroke! 2) Plan an immediate plan of action - Candidate for lytics? Anticoagulation? 3) Long term management Can we prevent future strokes?
What are the ways to prevent elevated intracranial pressure in patients with intracerebral hemorrhage and subarachnoid hemorrhage?
1) Keep head of bed elevated 2) Consider sedation (barbiturate coma) 3) Consider mannitol 4) Consider hyperventilation
What is the secondary prevention of stroke and TIA?
1) Lipid-lowering therapy (aggressive) - LDL 100 or less 2) Smoking cessation 3) Other cardiac risk factors 4) Stroke survivors average 10 outpatient visits/year
What are the causes of small vessel disease?
1) Lipohyalinosis 2) Atheroma formation (when cholesterol and fatty sub. that is carried in the blood accumulates on the inside lining of the arteries and form a yellow deposits)
What are the diagnoses that may mimic stroke (AKA the differential diagnosis)
1) Migraine 2) Seizures 3) Syncope 4) Transient global amnesia 5) Peripheral nerve disorders 6) Intracranial hemorrhage 7) Intracranial masses 8) Neuroses (panic, anxiety) 9) Metabolic disorders
What should be done after a intracerebral hemorrhage and subarachnoid hemorrhage that cause a stroke?
1) Prophylaxis for DVT and PE 2) Physical therapy, speech therapy, occupational therapy, swallowing studies 3) Recall that, of the patients who survive the acute period, only a little over half regain independent function - 30% remain incapacitated and require long-term care.
What are the "warning shots" of a stroke?
1) Sentinal bleeds (Warning bleed) 2) TIA
What does decreased oxygen supply in hypoperfusion (Anoxic Brain injury) cause?
1) Sepsis 2) Shock 3) Bleeding
What are the clinical features of small vessel disease?
1) Silent at first 2) AKA Lacunar infarcts 3) Step-wise progression 4) Slowly accumulates deficits - Pure motor hemiplegia - Dysarthria - Ataxic hemiparesis - Dementia (recall: multi-infarct dementia)
Describe the onset of a Sentinal bleeds (Warning bleed)
1) Sudden and severe headache 2) Typically 6-20 days before "THE BIG ONE"
What are the signs and symptoms of an intercerbral hemorrhage that has caused an elevated intracranial pressure (ICP)?
1) Vomiting 2) Decreased level of consciousness
Describe a Berry Anuerysm
1) very common in elderly 2) rupture can be life threatening 3) 35% fatality on 1st hemorrhage 4) Sudden, severe headache followed by coma 5) **Associated with polycystic kidney disease**
Why does death occur as a result of a stroke?
1.) Cells loose blood supply 2.) Aerobic metabolism stops 3.) Cells die 4.) Dead cells swell 5.) The amount of swelling depends on the volume of dead tissue 6.) Enlarging tissue increases the Intercranial pressure 7.) Blood flow decreases to the head - Remember what drives blood flow? 8.) Increased ICP (intercranial pressure) decreases blood flow which makes cerebral perfusion worse 9.) The area around an infarct becomes progressively hypoxic causing more swelling 10.) More swelling causes worse blood flow 11.) Eventually the brain becomes too big to stay in the cranium 12.) HERNIATION occurs (Next card, wait for it.....)
What are the symptoms of a stroke?
Abrupt onset v. gradual 1) Severe--> Subarachnoid hemorrhage (SAH) 2) Headache--> (97% of cases of SAH) 3) "Worst headache of my life"--> SAH 4) Vomiting 5) Consciousness - Initially brief w/ Lucid interval to follow 6) Neck Stiffness 7) Aseptic Meningitis
What is the Big complication of pushing throbolytics?
BLEEDING!! DO NOT PUSH LYTICS IN THE DARK
Why is a Subarachnoid hemorrhage is considered a stroke ONLY when it occurs spontaneously
Because a Subarachnoid hemorrhage can occur as a result of trauma as well
This is a small aneurysm at the base of the brain in the Circle of Willis
Berry Anuerysm
This is described as is death of an area of brain tissue (cerebral infarction) resulting from an inadequate supply of blood and oxygen to the brain due to blockage of an artery.
Ischemic Strokes
OK. BP control in HEMORRHAGIC stroke is handled a little differently. What should I keep the BP at in a Intracerebral hemorrhage or a subarachnoid hemorrhage?
Keep SBP between 140-160mmHg and monitor for signs of cerebral hypoperfusion induced by fall in BP
What is the DOC in a patient with a subarachnoid hemorrhage and why?
Labetalol (Because a patient will get increased blood flow with nitroprusside vasodilation)
What is the mot important diagnostic test for a stroke?
Noncontrast CT
This produces mass lesion that can compress the underlying brain.
Subdural or epidural hemorrhage
What is the most common cause of subarachnoid hemorrhage?
Rupture of a bulge (aneurysm) in an artery
What usually causes a rupture of an aneurysm?
Rupture usually comes from increased intracranial pressure - Valsalva/coughing/sneezing **Note** Bleeding is white
How can I control my patient's lipids?
STATINS 1) Statin therapy provides protection for all-cause mortality and nonhemorrhagic strokes 2) Statin therapy for all-stroke prevention: RR 0.84 (95% CI 0.79-0.91) 3) Statin therapy for all-cause mortality RR 0.88 (95% CI 0.88-0.93)
What is the most common disabling neurologic disorder?
STROKE!
This is bleeding into the space (subarachnoid space) between the inner layer (pia mater) and middle layer (arachnoid mater) of the tissue covering the brain (meninges).
SUBARACHNOID HEMORRHAGE
What is the sensitivity/ specificity of a non-contrast CT in diagnosing a Subarachnoid hemorrhage?
Sensitivity: 89%; specificity: 100%
This is bleeding into subarachnoid space, causing elevated intracranial pressure, vasospasm, and toxic effects.
Subarachnoid hemorrhage
What are the surgical options for patietns with TIA/stroke?
Surgical clipping or placement of coil for aneurysm Ligate or embolize AVM. Evacuation
This is described as when a thrombus formation in an artery causes decreased perfusion downstream and subsequent cell death
Thrombotic strokes
This is a sudden or rapid onset of neurologic deficit caused by cerebral ischemia. It may last for a few minutes or up to 24 hours and clears without residual signs. "a brief episode of neurologic dysfunction caused by focal brain or retinal ischemia, with clinical symptoms typically lasting less than 1 hour, and without evidence of acute infarction."
Transient ischemic attack (TIA)
What is used to detect cardiogenic and aortic sources for cerebral embolism?
Transthoracic and transesophageal echocardiography (TTE or TEE)
T or F. Acute infarction is seen sooner with MRI than CT
True
T or F. Transthoracic and transesophageal echocardiography can be postponed until after the acute treatment phase
True
When does a stroke occur?
When an artery to the brain becomes blocked or ruptures, resulting in death of an area of brain tissue (cerebral infarction) and causing sudden symptoms.
OK so how does bleeding cause a hemorrhagic stroke?
When blood vessels of the brain are weak, abnormal, or under unusual pressure, a hemorrhagic stroke can occur. In hemorrhagic strokes, bleeding may occur within the brain, as an intracerebral hemorrhage. Or bleeding may occur between the inner and middle layer of tissue covering the brain (in the subarachnoid space), as a subarachnoid hemorrhage
How does a acute subarachnoid hemorrhage appear on Non-Contrast CT?
acute hemorrhage appears bright on CT scan, whether in the brain itself, or outside the brain parenchyma (subarachnoid, subdural hemorrhage).
