Download STROKE: Defined - West Sound Advanced Practice Association

Filissa M Caserta MSN, ACNP-BC, CNRN
The Johns Hopkins Hospital
Neurosciences Critical Care Unit
Baltimore Maryland
STROKE: Defined
Destruction of a portion of brain tissue as a
result of circulatory failure in the distribution
of a specific arterial vessel
Epidemiology of Stroke
• 5,500,000 stroke survivors are alive today
• 700,000 each year
– 500,000 of these are first attacks
– 200,000 are recurrent attacks.
• Every 45 seconds, someone in the US has a stroke
• Every 3 minutes, someone in the US dies from a stroke
• 30% to 50% of stroke survivors do not regain functional
independence
• 15% to 30% of all stroke survivors are permanently disabled
• Public awareness about the signs of stroke should be
improved, so that patients and their loved ones realize when a
stroke is occurring
Incidence of Stroke
•
•
•
•
•
•
Increases with age
28% are less than 65 yrs old
80% of strokes are preventable
19% greater in men than women
Women > 65 have higher incidence than men
African Americans twice as likely to have a
stroke than Caucasians
Stroke: Classification
Two Broad Categories
ISCHEMIC
HEMORRHAGIC
• Too little blood
• Too much blood
• Intracerebral Hemorrhage • Thrombotic
(ICH)
• Embolic
• Subarachnoid Hemorrhage
(SAH)
• Intraventricular Hemorrhage
(IVH)
STROKE TYPES
•ISCHEMIC 84%
•Thrombotic 53%
•Embolic 31%
•HEMORRHAGIC 16%
•Intracerebral 10%
•Subarachnoid 6%
Circle of Willis
Arteries
that
supply
brain
STROKE TREATMENT
• Guidelines for Prevention of Stroke in
Patients With Ischemic Stroke or Transient
Ischemic Attack
• Guidelines for the Early Management of
Adults With Ischemic Stroke
• Guidelines for the Management of
Spontaneous Intracerebral Hemorrhage in
Adults
ISCHEMIC
STROKE
Risk Factors for Ischemic Stroke
AHA/ASA Guidelines
Primary Prevention of Ischemic Stroke
A Guideline From the American Heart
Association/American Stroke Association Stroke Council...
Stroke. 2006;37:1583
Risk Factors for Stroke
Not Modifiable
• Sex
• Age
• Race/ethnicity
• Low birth weight
• Genetics
Risk Factors for Stroke
• Modifiable- well documented
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–
–
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–
–
–
–
–
–
–
Hypertension
Heart Disease [Afib]
Carotid artery stenosis
Sickle cell disease
Postmenopausal hormone
therapy
Cholesterol level
Diabetes
Exposure to Cigarette Smoke
Poor diet
Physical Activity
Obesity
Body fat distribution
• Modifiable- Less well documented
–
–
–
–
–
–
–
–
–
–
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ETOH abuse
Drug abuse
BCP
Sleep disordered breathing
Migraines
Hyperhomocysteinemia
Elevated lipoprotein
Elevated lipoprotein-associated lipase
Hypercoagulability
Inflammation
Infection
Ischemic Stroke: Types
Thrombotic
• Cause: Platelet
Aggregation/Vessel
Occlusion
• Onset: During Sleep when
BP is lowest
• Risk Factors:
– Large Vessel Disease
• Atherosclerosis
• Dissection
• Arteritis
– Small Vessel Disease
• Chronic Hypertension
• Lacunar : small subcortical
infarcts
Embolic
• Cause: Fragments formed
outside the brain break off
and travel to a vessel in the
brain
• Onset: Abrupt, may occur
during exercise
• Risk Factors
–
–
–
–
Afib
Endocarditis
Valve Disease
Patent Foramen Ovale (PFO)
Transient Ischemic Attack
• A TIA is a rapidly reversible focal neurologic
deficit that usually lasts for less than 30 minutes
• Within 48 hours of the TIA there is an increased
risk of stroke
• A TIA workup should be given the same
importance as a stroke workup
• TIA is a warning sign; find the source, treat, and
hopefully prevent a stroke
Prevention of Recurrent Ischemic Event
• Guidelines for Prevention of Stroke in
Patients With Ischemic Stroke or Transient
Ischemic Attack
– A Statement for Healthcare Professionals From the
American Heart Association/American Stroke
Association Council on Stroke… Stroke.
2006;37:577
Prevention of Recurrent Ischemic Event
• Includes all strategies listed in primary prevention
document for BP, Smoking, Lipids, DM, weight
etc..
• ETOH; eliminate/reduce
• Medical and/or surgical intervention for:
– Arterial dissection
– Patent Foramen Ovale
Prevention of Recurrent Ischemic Event
• Medical management for the following:
–
–
–
–
–
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–
–
–
–
–
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Vertebrobasilar disease
Intracranial atherosclerosis
Atrial fibrillation
Acute MI and LV thrombus
Cardiomegaly
Valvular disease
“Cryptogenic” Infarcts
Lacunar Infarcts
Hypercoagulable states
Hyperhomocysteinemia
Cerebral venous thrombosis
Pregnancy
Ischemic Penumbra
• Definition:
– the area surrounding the infarcted
tissues that is potentially reversible
– The main goal of stroke therapy is to
preserve the ischemic penumbra!!!
Management of Ischemic Stroke
Guidelines for the Early Management of
Adults With Ischemic Stroke
A Guideline From the American Heart Association/ American
Stroke Association Stroke Council, Clinical Cardiology
Council, Cardiovascular Radiology and Intervention
Council, and the Atherosclerotic Peripheral Vascular
Disease and Quality of Care Outcomes in Research
Interdisciplinary Working Groups: The American Academy
of Neurology affirms the value of this guideline as an
educational tool for neurologists
(Stroke. 2007; 38:1655.)
Classification of Recommendations
Class I:
•
Conditions for which there is evidence for and/or general agreement
that the procedure or treatment is useful and effective
Class II:
– Conditions for which there is conflicting evidence and/or a
DO’s
divergence of opinion about the usefulness/efficacy of a
procedure or treatment
• Class IIa The weight of evidence or opinion is in favor of the procedure
or treatment.
• Class IIb Usefulness/efficacy is less well established by evidence or
opinion.
D
O
– Conditions for which there is evidence and/or general agreement
that the procedure or treatment is NOT useful/effective and in N
Ts
some cases may be HARMFUL
Class III
I. Pre-Hospital Management
Class I
• EMS
• Assessment
– Cincinnati Prehospital Stroke Scale
– Los Angeles Prehospital Stroke Screen
• Management
EMS Management
•
•
•
•
•
•
•
•
DO’s
Manage ABCs
Cardiac monitoring
Intravenous access
Oxygen (as required O2
saturation <92%)
Assess for hypoglycemia
NPO
Alert receiving ED
Rapid transport to closest
appropriate facility capable of
treating acute stroke
DON’T’S
• Dextrose-containing fluids in
nonhypoglycemic patients
• Hypotension/excessive
blood pressure reduction
• Excessive intravenous fluids
II. Designation of A Stroke Center
Class I
• Brain Attack Coalition recommended that stroke centers
be established
• Goal: to improve the organization and delivery of care to
stroke patients
• Certification through JCAHO began in 2004
– Standard measures for stroke (see end)
– Primary Stroke Center (PSC)
• Comprehensive Stroke Center (CPS)
II. Designation of A Stroke Center
PSC
CSC
• Have personnel,
• All for PSC PLUS
programs, expertise and
– Treat complicated strokes
including ICH/IVH / SAH
infrastructure to care for
– Have endovascular
uncomplicated strokes
capabilities
• Use many acute therapies
– Have ICUs to manage the
• Admit patient to a stroke
complicated stroke patients
unit
• JCAHO & ASA are
creating a formal process
for certification
III. Emergency Evaluation and Diagnosis
of Acute Ischemic Stroke (AIS)
Class I
• Organized protocol for emergency evaluation and
treatment plan within 60 minutes
• Acute stroke team to include MD/RN/
Lab/Radiology
• Use of stroke rating scale (preferably NIHSS—see
end)
• Lab tests
• Imaging
III. Emergency Evaluation and Diagnosis of
Acute Ischemic Stroke (AIS)
All Patients
Selected patients
• Noncontrast brain CT or brain
MRI (should not delay tx)
• Blood glucose
• Serum electrolytes/renal
function tests
• ECG
• Markers of cardiac ischemia
• CBC
• Coags
• Oxygen saturation
•
•
•
•
•
•
Hepatic function tests
Toxicology screen
Blood alcohol level
Pregnancy test
ABG (if hypoxia is suspected)
Chest radiography (if lung
disease is suspected)
• Lumbar puncture (if
subarachnoid hemorrhage is
suspected and CT scan is
negative for blood)
• Electroencephalogram (if
seizures are suspected)
IV. Early Diagnosis: Brain and
Vascular Imaging
Class I
• Imaging recommended prior to therapy: CT
provides the info you need
• Multi-modal CT and MRI can be helpful but
should not delay treatment
Class II
• For intra-arterial rtPA, surgery and endovascular
procedures, need vascular imaging
Ischemic stroke on HCT
V. General Supportive Care and
Treatment of Acute Complications
Class I
• ABCs
• Normothermia
• CV Monitoring and Treatment
• BP control –HTN
• BP control– Hypotension
– Avoid it
– Find and tx cause
• Glycemic control
V. General Supportive Care and
Treatment of Acute Complications
• HTN Management
– Controversial because data is ambiguous, however, it
is true that rapidly lowering BP does cause harm.
– Not eligible for tPA
• SBP< 220mmHg /or DBP < 120mmHg non-tPA
– Eligible for tPA
• Pre Rx: SBP <185 or DBP <110
• Post Rx: SBP < 180 or DBP <105
VI. Intravenous Thrombolytics
Class I
• IV tPA is the only FDA approved medical
therapy for patients with AIS
• Other thrombolytics are NOT recommended
outside of clinical trials
VI. Intravenous Thrombolytics
Intravenous rtPA (0.9 mg/kg, maximum dose 90 mg) is strongly
recommended for carefully selected patients who can be treated
within 3 hours of onset of ischemic stroke
Agent
• Tissue Plasminogen Activator [t-PA]
Timeframe:
• 3 hours for IntraVenous
Goals:
• Open the occluded vessel
• Re-establish blood flow
• Limit injury/Improve Outcome
VII. Intra-arterial tPA
Class I
• < 6 hours for selected patients who are NOT eligible
for IV tPA.
• Must be at an experienced stroke center with immediate
access to angio and interventionalists
Class II
• IA tPA is reasonable for pts who have
contraindications to IV tPA (recent surgery, age, time
frame)
• Class III
• Availability of IA tPA should NOT preclude IV tPA in
eligible patients
VIII. Anticoagulants
Class III
• VIII. Anticoagulation
– Urgent anticoagulation is NOT recommended for
treatment of AIS
– Should not be used in lieu of IV thrombolysis in eligible
patients
– Can cause hemorrhagic transformation
IX. Antiplatelets
Class I
• Aspirin : initial dose 325 mg
• Given within 24- 48 hours of stroke onset
Class III
• Aspirin should NOT be used as a substitute for other
acute interventions, especially intravenous
administration of rtPA
• ASA as an adjunctive therapy within 24 hours of rtPA is
NOT recommended
• Clopidogrel alone or in conjunction with ASA is NOT
recommended for AIS
X. Volume expansion/Vasodilators and
Induced Hypertension
Class I
• Induced HTN: In “exceptional” cases, an MD may
prescribe vasopressors to improve cerebral blood
flow
• Need close CV and neuro monitoring
Class III
• No hemodilution
• No vasodilators (methylxanthine derivatives)
XI. Surgical Intervention
• Immediate intervention
– Carotid Endarterectomy (CEA)
– Extracranial-intracranial arterial bypass (EC-IC
bypass)
• Insufficient data exists to make a recommendation
XII. Endovascular Intervention
Class II
• MERCI retrieval device is reasonable in carefully
selected patients although the utility of the
device in improving outcomes is unclear
• Other mechanical endovascular treatments
should be used in the setting of clinical trials.
XII. Endovascular Intervention
• Mechanical removal of clot
– Clinical trials have shown that thrombectomy with
mechanical thrombolysis devices is indeed feasible in
the treatment of acute stroke.
– Many devices have been discontinued
– MERCI Retriever has received FDA clearance.
XIII. Combination Reperfusion
Therapies in AIS
Class III
• Combo interventions to restore perfusion are NOT
recommended outside of clinical trials
**Combo =Using thromolysis combined with
antiplatlets/neuroprotection
XIV. Neuroprotective Agents
Class III
• No neuroprotection agents can be recommended
** Neuroprotective agents= nimodipine, NMDA, magnesium
and others
XV. Admission to Hospital & General Acute
Treatment after Hospitalization
Class I
•
•
•
•
•
•
Use of comprehensive, specialized stroke care
Use of standardized stroke ordersets
Early mobilization
Swallow eval BEFORE eat/drink
Treat UTI/pneumo with abx
DVT prophylaxis with SQ anticoagulation ( as well as early
mobilization and external compression devices)
• Treatment of concomitant medical disease
• Early intervention to prevent recurrent stroke
XV. Admission to Hospital & General Acute
Treatment after Hospitalization
Class II
• If cannot swallow, provide NG/OG/PEG nutrition
• ASA is potential intervention for DVT prophylaxis, but less
effective than anticoagulation.
• If cannot receive anticoagulation for DVT, use external
compression devices
Class III
• No nutritional supplements are needed for patients who can
swallow
• If possible, avoid using a foley due to high rosk of UTI
XVI. Treatment of Acute
Neurological Complications
Class I
• Treat increased ICP as using standard interventions
to decrease ICP
• For risk of malignant cerebral edema, transfer to
medical center with neurosurgical expertise
• EVD if hydro
• Decompressive surgical evacuation of spaceoccupying cerebellar infarctions
• Treat recurrent seizures
XVI. Treatment of Acute
Neurological Complications
Class II
• Although measure to decrease ICP are used, they
are unproven with AIS
• Decompressive Surgery for cerebral hemisphere
infarct
– Can be a life-saving measure
– Age, side of infarct
– Surgery may be recommended for seriously affected
patients
– If surgery is recommended, in-depth discussion with
families re: potential outcomes/disability should occur.
XVI. Treatment of Acute
Neurological Complications
Class III
• NO steroids
• NO prophylactic anticonvulsants
Palliative Care
• Ensure dialogue is occurring re: patient wishes
• Advanced directives
• Withdrawal of Life Support
Other Diagnostic Work-Up
• Additional work up
• LABS: TSH, RPR, Homocysteine, cholesterol, LDL,
HDL, triglycerides
– TESTS
• Transthoracic Echo
• Carotid Dopplers
HEMORRHAGIC
STROKE
Hemorrhagic Strokes: Types
• SAH (Subarachnoid Hemorrhage)
– Ruptured Aneurysm
• ICH (Intracerebral Hemorrhage)
– Hypertension
– Cocaine
– Many other
• IVH (Intraventricular Hemorrhage)
– Usually an extension of ICH
– Rarely isolated
Risk Factors for Hemorrhagic
Stroke
Modifiable
• HTN!!!
• IVDA- cocaine/amphetamines
• Chronic hypertension
ICH CAUSES
• Coagulopathy
– Thrombocytopenia
• Neoplasm
–
Malignant primary CNS
– Metastatic CNS tumor
– Hepatic failure
• Postendarterectomy reperfusion
– Factor deficiency
• Sinus thrombosis/venous
– Anticoagulant therapy
• Trauma
– Thrombolytic therapy
• Vascular anomalies
• Drugs
– Cocaine
– Sympathomimetics
• Hemorrhagic transformation
of cerebral infarct
• Infection
– Aneurysms/ Arteriovenous
malformations
– Vasculitis/Vasculopathy
– Amyloid angiopathy
– Moyamoya disease
Intracerbral Hemorrhages Location
A) Intracerebral hemorrhages most
commonly involve cerebral lobes,
originating from penetrating cortical
branches of the anterior, middle, or
posterior cerebral arteries
B) Basal ganglia, originating from
ascending lenticulostriate branches of
the middle cerebral artery
C) Thalamus, originating from ascending
thalmogeniculate branches of the
posterior cerebral artery
D) Pons, originating from paramedian
branches of the basilar artery
E) Cerebellum, originating from penetrating
branches of the posterior inferior,
anterior inferior, or superior cerebellar
arteries
Spontaneous Intracerebral Hemorrhage Adnan I. Qureshi, M.D., Stanley Tuhrim, M.D., Joseph P. Broderick, M.D., H. Hunt Batjer, M.D Hidek Hondo, M.D., and Daniel F.
Hanley, M.D. NEJM.Volume 344:1450-1460 May 10, 2001 Number 19
ICH Management
Guidelines for the Management of
Spontaneous Intracerebral Hemorrhage
in Adults
2007 Update: A Guideline From the American Heart Stroke
Association Stroke Council, High Blood Pressure Research
Council, and the Quality of Care and Outcomes in
Research Interdisciplinary Working Group: The American
Academy of Neurology affirms the value of this guideline
as an educational tool for neurologists
(Stroke. 2007; 38:2001.)
Emergency Diagnosis and
Assessment of ICH
Class I
• ICH is a medical emergency, with frequent early,
ongoing bleeding and progressive deterioration, severe
clinical deficits, and subsequent high mortality and
morbidity rates, and it should be promptly recognized
and diagnosed
• CT and magnetic resonance are each first-choice initial
imaging options; in patients with contraindications to
magnetic resonance, CT should be obtained
• ***Angiography- if high suspicion of vascular anomaly
ICH
IVH
Treatment of Acute ICH/IVH
Class I
• Monitor in an ICU
• Antiepileptic drugs (AEDs) to treat
seizures
• Treat and decrease fever
• Early mobilization and rehab
Treatment of Acute ICH/IVH
Class II
• ICP-manage using a variety of medical therapies
as well as EVD if hydro; CPP goal > 70 mmHg
• Glycemic control (treat > 140mg/dL)
• BP control: SBP < 180 and MAP < 130; CPP 6080
• Factor rFVIIa
• “Brief” period of prophylactic AEDs soon after
ICH may decrease risk of seizures especially in
lobar hemorrhage
Treatment of Acute ICH/IVH
• If SBP is >200 mm Hg or MAP is >150 mm Hg, then consider
aggressive reduction of blood pressure with continuous IV meds
monitor BP q 5 minutes.
•
If SBP is >180 mm Hg or MAP is >130 mm Hg and there is
suspicion of increased ICP, reducing blood pressure using
intermittent or continuous IV meds to keep CPP perfusion
pressure >60 to 80 mm Hg
• If SBP is >180 mm Hg or MAP is >130 mm Hg and no suspicion
of elevated ICP, then consider a modest reduction of blood
pressure (eg, MAP of 110 mm Hg or target blood pressure of
160/90 mm Hg) using intermittent or continuous intravenous
medications to control blood pressure, and clinically reexamine the
patient every 15 minutes.
Treatment of Acute ICH/IVH
Class II
• rFVIIa
• Treatment with rFVIIa within the first 3 to 4 hours
after onset to slow progression of bleeding has
shown promise in one moderate-sized phase II trial
• However, the efficacy and safety of this treatment
must be confirmed in phase III trials before its use
in patients with ICH can be recommended outside
of a clinical trial
Prevention of DVT and PE
Class I
• Hemiparesis/hemiplegia ---should have intermittent
pneumatic compression
Class II
• Prophylaxis:
– after 3-4 days
– once documented bleeding has stopped
– low-dose subcutaneous low-molecular-weight heparin or
unfractionated heparin
• Treatment
– Placement of a vena cava filter
– Long-term antithrombotic therapy after placement of a vena cava
filter must look at risk of rebleed vs risk of thrombus
ICH Related to Fibrinolysis
Carries a poorer prognosis because bleeds tend to be huge
Class I
• Heparin---Protamine sulfate (dose depends on time heparin
stopped)
• Coumadin– Vitamin K IV (10mg) with treatment to replace
clotting factors
Class II
• Replace clotting factors
– Prothrombin complex concentrate, factor IX complex
concentrate, and rFVIIa; quick and less volume
– FFP; large volumes and longer infusion time
ICH Related to Fibrinolysis
When to restart anticoagulation after ICH??
Class II
• Consider:
– Risk of subsequent arterial or venous thromboembolism
– Risk of recurrent ICH
– Overall state of the patient
• If low risk of thromboembolic event, may restart
antiplatelet instead of warfarin
• If warfarin must be restarted, wait 7-10 days after ICH
Surgery
• Surgical Approaches
• Timing of Surgery
• Decompressive Craniectomy
• International Surgical Trial in Intracerebral Hemorrhage
(STICH)
• New NIH study: Minimally Invasive Stereotactic Surgery + rtPa for ICH Evacuation (MISTIE)
Surgical Approaches
Class I
• Cerebellar ICH > 3cm with neuro deterioration /herniation or
hydro should have removal of hemorrhage
Class II
• Lobar clots within 1 cm of the surface may be considered for
standard craniotomy
• Stereotactic infusion of urokinase into clot
– decreases size of clot and risk of death BUT it’s usefulness is UNKNOWN
• Minimally invasive clot evacuation via mechanical devices
– needs further testing therefore it’s usefulness is UNKNOWN
Class III
• Evacuation of supratentorial ICH by standard craniotomy within
96 hours is NOT RECOMMENDED except as noted above
Decompressive Craniectomy
Class II
• Too few data currently exist to comment on the
potential of decompressive craniectomy to
improve outcome in ICH
Withdrawal of Life Support
• We recommend careful consideration of aggressive
full care during the first 24 hours after ICH onset
and postponement of NEW DNR orders during that
time.
• In all cases, physicians and nurses caring for ICH
patients who are given DNR status should be
reminded that the designation relates only to the
circumstance of cardiopulmonary arrest and that
patients should receive all other appropriate medical
and surgical interventions.
Prevention of Recurrent ICH
Class I
• Treating hypertension in the nonacute setting is the
most important step to reduce the risk of ICH and
probably recurrent ICH as well
• Smoking, heavy alcohol use, and cocaine use are
risk factors for ICH, and discontinuation should be
recommended for prevention of ICH recurrence
• 72 yo white male
• PMHx:
Case Study
– Mild HTN
• Meds
– Lisinopril 10mg qday
• Family Hx
– Mom- s/p cva
– Dad- s/p cva x 2
• Social
– MS in Civil Engineering
– Working as tunnel expert FHWA
Case Study
•
•
•
•
•
Home alone
“Didn’t feel well”
Sudden onset right sided weakness
Called 911—could he talk??
EMS Arrives---house locked—tic-toc tPA
minutes!!
• Establish TOSO??
Case Study
• Since could not establish TOSO, no thrombolytics
• Cause?
– Undiagnosed afib with SLOW ventricular response
• Rx
– Pacemaker
– Heparin--- Coumadin
– Acute rehab after 72 hours!
• Rehab
– Acute 30 days
– Day Hospital 2 months
- Subacute 3 months
- Outpatient
PRE STROKE HAWAII 1996
POST STROKE HAWAII 2005
THERE IS LIFE AFTER STROKE!!
Cincinnati Prehospital Stroke Scale
Last time seen normal ________________
Evaluate for Facial Droop
Present?
Absent?
Hold up arms and look for Drift
Present?
Absent?
Repeat “The sky is blue in
Cincinnati.
Abnormal?
Normal?
BP__________
Blood sugar___________
History of anticoagulant medications ? Warfarin_____
Heparin ________
Patients with 1 of these 3 findings -as a new event - have a 66% probability of
an ischemic stroke. If all 3 findings are present the probability of an acute stroke
is more than 88%
Los Angeles Prehospital Stroke Screen
• Last time patient known to be symptom free
• Screening
–
–
–
–
–
Age >45 y
No history of seizures or epilepsy
Symptoms present <24 h
Not previously bedridden or wheelchair bound
If unknown or yes
•
Blood glucose 60 to 400 mg/dL Yes No
Examination
• Exam
– Facial smile grimace
– Grip
– Arm strength (drift)
• Based on examination, patient has unilateral weakness Yes
No
• If items are yes or unknown, meets criteria for stroke
NIHSS
• National Institutes of Health Stroke Scale (NIHSS)
– The initial NIHSS score provides important prognostic
information.
– Approximately 60% to 70% of patients with an acute
ischemic stroke and a baseline NIHSS score <10 will
have a favorable outcome after 1 year as compared with
only 4% to 16% of those with a score >20.
– The NIHSS score can also help identify those patients
at greatest risk for ICH associated with thrombolytic
treatment.
Designation of A Stroke Center
JCAHO Standard Measures
• tPA considered
• Screen for dysphagia
• Deep vein thrombosis prophylaxis
• Lipid profile during hospitalization
• Smoking cessation
• Education about stroke
• Plan for rehabilitation considered
• Antithrombotic medications started within 48 hours
• Antithrombotic medications prescribed at discharge
• Anticoagulants prescribed to patients with a-fib