Stroke Flashcards
A stroke is also known as a ____.
Cerebral Vascular Accident (CVA)
What is a stroke? What are the two types of stroke?
Sudden loss of neurological function as the result of a disruption to blood flow resulting in tissue death.
Types:
- Ischemic
- Hemorrhagic
Stroke is the ___th leading cause of death in the US
5th
Leading cause of serious long term disability
What are the top 3 CONTROLLABLE risk factors for stroke? List the other 5 controllable risk factors.
- Hypertension (BP > 160/95 mmHg)
- Smoking (increases risk by 50%)
- Hyperlipidemia
Cardiac disease Diabetes Obesity Sedentary lifestyle Excessive alcohol consumption (>3-4 drinks/day increases risk by 40%)
What are 5 risk factors for stroke that we CANNOT control?
- Age (incidence increases with age)
- Sex (Females 20% < men, levels out with age)
- Heredity (risk greater with family history)
- Race (African Americans > Hispanics > Caucasians)
- Geography (Southeast US highest death rate)
What are 5 warning sign of stroke?
- Sudden numbness/weakness of face/arm/leg
- Sudden difficulty speaking or understanding speech; increased confusion
- Sudden trouble seeing in one or both eyes
- Sudden trouble walking, dizziness, loss of balance or coordination
- Sudden severe headache with no known cause
What is the relationship between time and stroke related disability?
Those who arrive to the ED within 3 hrs. of the start of symptoms tend to have less disability 3 months post CVA
What does the acronym FAST stand for?
Facial droop
Arm weakness
Speech difficulties
Time (tongue deviation)
What are 9 diagnostic tests that can be done to detect stroke?
- Non contract CAT scan (common): differentiates ischemic from hemorrhagic
- MRI: assess size/extent of infarct
- MRA: assess atrial stenosis/presence of aneurysm
- EKG: detects Afib
- Echo: assess heart ventricular/valve function
- Echo with bubble: r/o patent foramen ovalus (PFO)
- Telemetry: min 24 hours
- Carotid Doppler: detects stenosis due to plaque accumulation
- TEE (trans esophageal echocardiogram): determines origin/source of infarct
What is tPA? When should it be used (timeframe)? Why is it important?
tPA- tissue plasminogen activator
Results in lysis of fibrin
Used with ischemic stroke to prevent disability post event
Use with 3 hours of the stroke for optimal results
What is the University of Oxford ABCD Scale?
Performed in MD office
***Predictor of stroke after TIA
Scale:
- Age—1 point over 60
- Blood Pressure—1 point for systolic above 140 mmHg or diastolic above 90 mmHg
- Clinical features—- 2 points for one sided weakness and 1 point for speech issues w/o weakness
- Duration—2 points for symptoms > 60 min and 1 point < 60 min
Score w/in 7 days: 0-4=4% chance,5=12% chance, 6=32% chance
What is the NIH stroke scale?
Standardized tool to assess if impairments warrants use of tPA
Performed at:
- Baseline
- 2 hrs. post treatment
- 24hrs from symptom onset
- 7-10 days later
- 3 months
Max score of 42 (severe stroke)
score of 12-20 = best outcomes
___ % of all CVAs are ischemic.
80%
What is an ischemic stroke?
Decreased blood flow resulting in tissue death
What are 2 types of ischemic stroke?
- Thrombotic: aggregation of platelets & fibrin in a cerebral artery resulting in occlusion
gradual onset
often awaken with symptoms - Embolic: thrombus that originates elsewhere breaks away and is carried through bloodstream to a narrowing region
abrupt onset; often with activity
most common area of origin is cardiac—post surgery
What is a lacunar infarct?
Occlusion of small vessels; may be gradual onset
Associated with hypertension or diabetes
Tissue death is evident
What is a transient ischemic attack?
Short period of disrupted blood flow with complete recovery of symptoms
Symptoms recover within 24 hours
15% of CVA’s had a reported TIA
What occurs in an ischemic cascade?
Refer to slide 22 of the stroke PPT
Too much info and I’m not about to type it all out
What is an ischemic penumbra?
Rim of mild to moderately ischemic tissue around the area of infarction is evolving
Remains viable for several hours due to collateral arteries
Tissue death if reperfusion is not established during the early hours
Brain tissue requires ____ % of regular blood flow to survive.
20-25%
What are 5 common medications prescribed post stroke?
- Antiplatelets (prevents clot formation)
- Anticoagulants (increase clotting time)
- Statins (blocks enzymes that produce LDL cholesterol)
- Antihypertensive (beta blockers/ACE inhibitors)
- Diabetic Medications
What are the symptoms associated with a hemorrhagic stroke?
Sudden onset
Closely linked to HTN
Decreased level of consciousness, headache, nausea and vomiting
What are 4 types of hemorrhagic strokes?
- Intracerebral hemorrhage
- Subarachnoid hemorrhage
- Subdural hematoma
- Epidural hematoma
What is an intracerebral hemorrhage? What percentage of strokes are they responsible for?
Arterial bleeding into the brain parenchyma (intraparenchymal hemorrhage)
Responsible for 15% of all strokes
High mortality rate from stroke is dependent on what 4 factors?
- size
- degree of neuro deficits
- location (midline = mortality)
- rapid development
What is the underlying etiology of primary intracerebral hemorrhage (ICH)?
- Atherosclerosis weakens small arterial walls
- Sudden increase in BP
- Over 65 yo doubles w/ each decade
What are the 3 clinical manifestations of ICH?
- specific to region
- sx increase as hematoma enlarges
- seizure activity possible (esp. in cerebral cortex)
What 3 things occur as a result of an ICH?
- Distortion of structures
- Rise in intracranial pressure
- Development of severe edema causing midline shift
What is a subarachnoid hemorrhage? What are the symptoms associated with this condition?
Blood in the subarachnoid space
Sudden onset with sever headache
Nausea/vomiting, syncope, neck pain, coma, confusion, lethargy
What are the causes of a subarachnoid hemorrhage?
- AVM—congenital defect-most common cause of SAH (80%)
- Berry Aneurysm most common–often occurs at bifurcation of vessels esp. at Circle Of Willis
- Age (highest incidence > 70 yo female)
- Trauma
- Neoplasm
- Infection
- HTN
- Vascular malformations
- Smoking
- Familial
What is the prognosis and medical management for a subarachnoid hemorrhage?
Prognosis is good <3cm
Medical mgmt: evacuation of hematoma w/resection of aneurysm or coiling
What is a subdural hematoma? What is the typical presentation?
Trauma results in tearing of the bridging veins between the brain surface and dural sinus
Subset is chronic esp in elderly—caused by slow leakage of small vein. Presents with decline in cognitive and/or functional status
Small—absorbed by body
Large—becomes space occupying req. evacuation
What is an epidural hematoma?
Traumatic tearing of the meningeal arteries that supply the periosteal layer of the dura
Medical emergency req. evacuation immediately as can cause compression brainstem
Anterior circulation begins in the carotid arteries and supplies what 5 areas?
- Frontal lobe (executive function)
- Parietal lobe (movement/orientation)
- Basal ganglia (movement regulation)
- Internal capsule
- Temporal lobes (auditory, speech, memory)
What is the most common area for lacunae infarcts?
Internal capsule
Posterior circulation begins in the vertebra-basilar arteries and supplies what 4 areas?
- Occipital lobe (visual processing)
- Posterior temporal lobe (visual processing for object and pattern recognition)
- Cerebellum (coordination, balance, posture)
- Brainstem
What is aphasia?
Difficulties in speaking, listening, reading, and writing, but does not affect intelligence
What are the 3 types of aphasia?
- Broca’s: expressive, non-fluent, some subtle receptive problems, anterior(posterior aspect frontal lobe)
- Wernicke’s: receptive, fluent, poor self monitoring, posterior(temporal to parietal lobe)
- Global Aphasia: receptive/expressive—full MCA infarct affection both frontal and parietal lobes
What is alexia?
Impairment in reading–know they are letters but unable to decode
What is agraphia?
Impairment in writing
What anatomical areas are affected if a patient presents with both alexia and agraphia?
Issue with visual assc. cortex w/ wernicke’s and motor cortex
What is apraxia?
Inability to execute a voluntary motor movement despite being able to demonstrate muscle function
Understands requirement
Present with and without paresis (frontal and parietal region)
What is agnosia?
Loss of ability to perceive auditory, visual, tactile input though sensory systems are intact
What is anosognosia?
Lack of awareness of illness (parietal lobe lesion)
What is dysarthria?
Motor speech disorder affecting respiration, articulation and phonation
What is dysphagia?
Inability/difficulty in swallowing due to CN involvement includes CN V, VII, CN IX-CN XII
What is preservation?
Unable to refrain from certain behaviors—NO brakes
eg. might not be able to get off a specific topic during conversation
What is seen in an UE flexor synergy?
Scap retraction/elevation Shoulder abduction Elbow flexion Forearm supination Wrist/finger flexion
What is seen in an UE extensor synergy?
Scap retraction Shoulder add/IR Elbow extension Forearm pronation Wrist/finger flexion
What is seen in an LE flexor synergy?
Hip flex/abd/ER
Knee flexion
Ankle DF/INV
Toe DF
What is seen in an LE extensor synergy?
Hip ext/add/IR
Knee extension
Ankle PF/INV
Toe PF
What is homonymous hemianopsia?
Loss of half of the field of view on the same side in both eyes.
***Good pic on slide 48
Anterior Cerebral Artery (ACA) is responsible for less than ___% of CVAs
3%
What deficits are noted with an ACA CVA?
Hemiplegia/paresis – leg more involved than arm
Hemisensory deficits
Urinary incontinence
Difficulty bimanual tasks or imitation
Aphasia if dominant hemisphere (Wernicke’s—receptive, fluent)
Apraxia if non-dominant hemisphere
Personality/behavior changes – impulsive/loss of inhibition
What is the most common region for a CVA? (%)
Middle cerebral artery (51%)
What 4 deficits are apparent with a CVA of the superior division of the MCA?
- Contralateral hemiparesis/ hemiplegia
- Contralateral sensory loss
- Left hemispheric: Broca’s expressive aphasia
- Right hemispheric: Visual perceptual disorders—neglect/depth perception
What 3 deficits are apparent with a CVA of the inferior division of the MCA?
- Homonymous hemianopsia—loss of temporal vision of one eye and nasal of the other
- Left hemispheric=Wernicke’s aphasia (fluent aphasia unable to process auditory language)
- Right hemispheric=Left visual neglect
What deficits are seen with a complete MCA occlusion?
Global aphasia Hemiplegia—UE/face>>LE Hemisensory loss Left neglect or inattention Visual-perceptual and spatial-perceptual deficits Perseveration Anosognosia (denial of disease)
What are the functions of the right hemisphere?
Responsible for learned behaviors that require voluntary initiation, planning and spatial perceptual judgement
What are the functions of the left hemisphere?
Responsible for learning and using language symbols
What are the clinical signs/sxs present with right hemisphere damage?
Left hemiplegia/paresis visual-spatial perceptual deficits Impulsive Poor judgement Labile Memory deficits subtle communication problems Left sided sensory loss
What are the clinical signs/sxs present with left hemisphere damage?
Right hemiplegia/paresis Right sensory loss Delayed processing of verbal cues Aphasia Apraxia Slow cautious behaviors Memory deficits
What are 3 characteristics associated with Pusher syndrome?
- Spontaneous body posture—towards side of involvement
- Increase of pushing force by spreading the non paretic limbs
- Resistance to passive correction of posture (in seated and standing posture)
How is Pusher syndrome treated?
Treatment combines visual, somatosensory and motor learning
Allow pt. to “fall” from pushing—mimic sensation of falling
Use of vision–attain posture to mimic vertical objects (eg. Mirror)
Sitting weight-shift
Progression sit to stand
Single leg activities—step ups with uninvolved
Functional training—to uninvolved side
Body weight supported gait training
What deficits are seen with a PCA CVA?
Hemiparesis
Impairment of light touch and deep pressure (due to thalamic involvement)
Thalamic syndrome – intolerable pain and sensory perseveration
Homonymous hemianopsia
Receptive aphasia–dominant side
Ipsilateral choreoathetoid movement, ataxia or tremor
Visual agnosia—do not recognize objects
What 2 deficits are seen with a complete occlusion of the PCA?
- CN III palsy and ataxia (Claude Syndrome)
2. CN III palsy w/ hemiplegia (Weber’s Syndrome)
What 6 sxs are present in patients with cerebellar artery syndrome?
Ipsilateral ataxia Loss of pain and temp in contralateral ext./torso/face Dysmetria of ipsilateral UE>>LE Dysarthria Nausea/vomiting Vertigo
Name 2 vertebrobasilar artery syndromes
- Wallenberg syndrome
2. Horner’s syndrome
What sxs are associated with Wallenberg syndrome?
Dysphagia
Dysphonia
Vertigo
Nystagmus
Ipsilateral ataxia, dyskinesia(jerky motion) or intention tremor
Impaired sensation ipsilateral face/contralateral torso/limbs
What sxs are associated with Horner’s syndrome?
ptosis of eyelid constriction of pupil loss ipsilateral facial sweating Dysphagia/dysphonia loss pain and temp sensation contralateral torso/limbs
A complete occlusion of the basilar artery will result in ____? (high or low mortality rate?
Locked in syndrome
high mortality rate
What are the characteristics of patients with locked in syndrome?
Tetraplegia
Cognition spared
Bilateral cranial nerve palsy(no horizontal eye movement)
Mute
