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K:\STROKE CENTER\Staff Learning Opportunities\eLearn\MOD1 (rev. 01.18.08)
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STROKE: The Brain MattersModule I
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Prevalence and incidence: From 1970s to early 1990s, non-
institutionalized stroke survivors increased from 1.5 million to 2.4 million
On average, every 45 seconds someone in the U.S. has a stroke
Each year 700,000 people experience a new or recurrent stroke
Blacks have almost twice the risk of first-ever stroke compared with whites
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Impact of stroke
Stroke accounted for about one of every 15 deaths in the U.S. in 2003
Stroke ranks No. 3 among all causes of death 8-12% of ischemic strokes and 37-38% of
hemorrhagic strokes result in death within 30 days
Top cause of disability
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Estimated Direct and Indirect Costs of Major Cardiovascular Diseases and StrokeUnited States: 2006
Source: Heart Disease and Stroke Statistics – 2006 Update
142.5
57.9 63.5
29.6
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What is Stroke? BRAIN ATTACK Clinical diagnosis supported by testing Abrupt onset of neurologic deficit
attributable to a focal vascular cause Sudden loss of blood, with subsequent loss of
nutrients and oxygen to a part of the brain, causing cell death
Ischemic vs. Hemorrhagic
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Ischemic strokes: 80% of all strokes
Ischemic strokes occur if blood flow is blocked locally in an artery supplying the brain or if the entire circulation fails so that all organs, including the brain, are inadequately perfused
What might block a brain artery? 1. Pathology such as atherosclerotic plaque in the vessel's wall that narrows or even obliterates its lumen or produces complete collapse of the wall 2. A "plug" in its lumen formed by material carried in the blood 3. Abnormally high pressure in brain tissue surrounding the vessel that compresses its wall to the point of squeezing shut its lumen
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Ischemic stroke Cerebral thrombosis most
common and occurs in arteries narrowed by cholesterol plaque
Cerebral embolism occurs when a wandering clot or other particle forms away from the brain (usually the heart or aorta) and this clot occludes an artery leading to the brain
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Hemorrhagic stroke: 20% of all strokes
Half involve rupture of either aneurysms which initially bleed into the subarachnoid space or of arteriovenous malformations which are often located within the brain and therefore tend to bleed into the brain itself. Both of these pathologies are thought to be the consequence of developmental abnormalities and are characterized by thinned vascular walls
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Intracerebral Hemorrhage Caused by rupture of the walls of small penetrating
arteries serving deep structures, with bleeding directly into the brain and its ventricles
These vessels are at particular risk because of their thin muscular walls and narrow lumens. It is thought that the cumulative effects of untreated hypertension and atherosclerosis or other kinds of pathologic changes weaken their walls and put them at special risk for rupture
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Lobar hemorrhages Small arteries supplying the superficial regions of
the cerebral hemispheres may develop deposits of an abnormal protein called amyloid in the extremely elderly
In some cases, this material can weaken the walls of these vessels to the extent that they rupture and cause hemorrhages in the superficial regions of the hemispheres
Unlike the intracerebral hemorrhages involving midline penetrating vessels, superficial lobar hemorrhages can occur in individuals who have had normal blood pressure throughout
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Transient Ischemic Attack (TIA) Symptoms and causes similar to stroke Important RISK FACTOR; about 15% of all
strokes are heralded by a TIA TIAs are produced by transient blockage of the
cerebral or retinal circulation. Typical duration of symptoms is 5-15 minutes
By definition, neurologic deficits that resolve in <24 hours
Evaluation parallels that of stroke
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Risk factors for stroke after TIA Age over 60 years Diabetes mellitus Symptom duration more than 10 minutes Residual weakness or speech disturbance
N Eng J Med 4/17/03
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Brain anatomy:
www.tbts.org/assets/ images/brainmap.gif
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Different parts of the brain: Cerebrum ~ The cerebrum (supratentorial or front of brain) is
composed of the right and left hemispheres. Functions of the cerebrum include: initiation of movement, coordination of movement, temperature, touch, vision, hearing, judgment, reasoning, problem solving, emotions, and learning.
Brainstem ~ The brainstem (midline or middle of brain) includes the midbrain, the pons, and the medulla. Functions of this area include: movement of the eyes and mouth, relaying sensory messages (hot, pain, loud, etc.), hunger, respirations, consciousness, cardiac function, body temperature, involuntary muscle movements, sneezing, coughing, vomiting, and swallowing.
Cerebellum ~ The cerebellum (infratentorial or back of brain) is located at the back of the head. Its function is to coordinate voluntary muscle movements and to maintain posture, balance, and equilibrium.
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More specific areas of the brain: Pons ~ A deep part of the brain, located in the brainstem, the pons contains many of
the control areas for eye and face movements.
Medulla ~ The lowest part of the brainstem, the medulla is the most vital part of the entire brain and contains important control centers for the heart and lungs.
Frontal lobe ~ The largest section of the brain located in the front of the head, the frontal lobe is involved in personality characteristics and movement.
Parietal lobe ~ The middle part of the brain, the parietal lobe helps a person to identify objects and understand spatial relationships (where one's body is compared to objects around the person). The parietal lobe is also involved in interpreting pain and touch in the body.
Occipital lobe ~ The occipital lobe is the back part of the brain that is involved with vision.
Temporal lobe ~ The sides of the brain, these temporal lobes are involved in memory, speech, and sense of smell.
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Cerebrovascular circulation
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Stroke Symptomso Sudden numbness or weakness of face, arm or leg
especially on one side of the bodyo Sudden confusion, trouble speaking or
understandingo Sudden trouble seeing in one or both eyeso Sudden trouble walking, dizziness, loss of balance
or coordinationo Sudden severe headache with no known cause
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Neurologic symptoms of occluded vessels will vary depending on location
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Vessels typically effected and an overview of possible symptoms
Middle cerebral artery
Vertebrobasilar artery
Anterior cerebral artery
Posterior cerebral artery
Carotid artery
Aphasia, visual field defects, hemi paresis, hemiplegia, hemi sensory loss, inattention, apraxia.
Diplopia, dysarthria, ataxia, poor motor coordination, vertigo, nausea/vomiting.
Personality changes, confusion, weakness usually> distally, hemiplegia.
Cortical blindness, dyslexia, visual field defects if occipital.
Altered level of consciousness, weakness, numbness.
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American Heart Association’s 7 “D’s” of Stroke Care
Detection, early recognition of the signs and symptoms and determination of onset time. If the patient awakened with signs and symptoms of a stroke, the onset time is considered the last time he was seen awake without them.
Dispatch, rapidly getting the patient emergency medical care. Delivery, transporting him to the nearest stroke center or a hospital capable of following
the latest stroke guidelines. Door, rapid triage in the ED. Data, documenting or collecting information about the patient's history, lab work,
imaging studies, examinations, physical assessments, and time of onset of signs and symptoms. Needs to undergo a noncontrast computed tomography (CT) scan of the brain within 25 minutes of arrival at the ED, and it must be interpreted within 45 minutes of arrival to determine if an acute ischemic stroke occurred.
Decision, answering the inclusion and exclusion criteria for t-PA therapy and reviewing treatment options with the patient and family.
Drug, starting t-PA treatment within 3 hours of onset of symptoms if all conditions are met; Nursing care at the door.
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Diagnostics Lab work: Complete blood cell count, glucose
and electrolyte levels, renal and liver function studies, prothrombin and partial thromboplastin times, and cardiac biomarkers
12-lead electrocardiogram CT of brain (w/angiography IF indicated and
does not delay administration of t-PA) CT of brain with angiography
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Timing is critical!!Three (3) hour window of time to receive acute treatment for ischemic stroke.
ED Ischemic stroke pathway:
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t-PA (Tissue Plasminogen Activator) Inclusion / Exclusion Criteria
Inclusion Criteria: Clinical diagnosis of stroke Age 18 or older Time of stroke onset (i.e. last time pt witnessed to be well) < 3 hours BP Systolic <= 185, diastolic <= 110 (can receive 1-3 doses of BP agent for control) Pro time <= 15 seconds or INR <= 1.7 Platelet count >= 100,000 Blood Glucose => 50 and <= 400 mg/dl Exclusion Criteria: Minor stroke or rapidly resolving stroke Seizure at onset of stroke Heparin treatment during the past 48 hours with an elevated PTT Evidence of acute myocardial infarction Exclusion Criteria (Relative Contraindications): History of prior intracranial hemorrhage, neoplasm, AVM or aneurysm Major surgical procedures within 14 days Stroke or serious head injury within 3 months Gastrointestinal or urinary bleeding within last 21 days Lactation or Pregnancy within 30 days
Modified from NINDS criteria
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t-PA dose and administrationTissue Plasminogen Activator (t-PA)
Alteplase (Activase®)
Drug class = Fibrinolytic used to treat acute ischemic stroke. Clot-specific binding to fibrin-bound plasminogenallowing conversion to plasmin, which digests the fibrin.
Onset of action occurs in 60-90 minutes.
LOADING dose = 0.09 mg/kg IV push over 1 minute (dose not to exceed 9 mg)
Followed by: INFUSION dose = 0.81 mg/kg IV infusion over 1 hour (dose
not to exceed 81 mg)
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Order sets used by the ED:
Link: ??
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Post-thrombolytic order set Key issues: ASA, heparin, Coumadin
contraindicated up to 24 hrs. after t-PA administered
NPO until swallow evaluated Assess for changes in neuro status that may
indicate post t-PA complication of bleeding Assess any other abnormal bleeding
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Other ED pathways: TIA and Hemorrhagic
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Stroke Patient Placement Patient placement is planned with use of
designated stroke unit beds unless other factors determine otherwise
After t-PA, patients are monitored in CICU 18-24 hrs (or SCU). If stable, they are then transferred to P3CD (R4, if tele needed)
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Stroke Bed Aggregation:
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Act F.A.S.T.If you think someone may be having a stroke, act F.A.S.T. and do thissimple test: FACE Ask the person to smile.
Does one side of the face droop? ARMS Ask the person to raise both arms.
Does one arm drift downward? SPEECH Ask the person to repeat a simple sentence.
Are the words slurred? Can he/she repeat the sentence correctly? TIME If the person shows any of these symptoms, time is
important. Call 911 or get to the hospital fast. Brain cells are dying.
TIME LOST IS BRAIN LOST!
NINDS