CVA/Stroke Flashcards
Concepts & Pathophysiology
Priority: perfusion
Interrelated concepts: cognition, mobility, sensory perception
- Brain tissue, blood, & CSF occupy the skull
- If 1 increases, others dec to maintain equilibrium
Causes
- Blockage of a blood vessel
- Ischemic stroke
- Bleeding into the brain
- Hemorrhagic stroke
Stroke Risk Factors: Modifiable
- HTN ! most common risk
- DM/obesity/cardiovascular (afib, PFO)
- Illicit drug use esp cocaine
- Smoking/heavy alcohol use
- Sleep apnea
- Aneurysm
- Hormone use/oral contraceptives/anticoags/anti-platelets
- Preeclampsia
- Use of phenylpropanolamine (PPA) used in antihistamines
Non-Modifiable
- Age >55
- Race > African Americans
- Gender > women
- Family medical hx
There is often a zone of tissue surrounding an infarction called the ___ ___ that contains ischemic tissue that is not irreversibly damaged
ischemic penumbra
Ischemic stroke
- Sudden blockage of a cerebral blood vessel
- Causes reduction of oxygenated blood to the brain, resulting in an abrupt onset of clinical manifestations
- Ischemic penumbra
- Cerebral blood vessels may be opened or recanalized using IV recombinant tissue plasminogen activator (IV rt-PA)
> Authorized to treat acute ischemic stroke
> Allows a blood clot to be dissolved @ the site
> Restores blood flow to ischemic neuronal tissue
?
This intervention involves a cerebral angiogram to locate a vessel occlusion accompanied by delivery of thrombolytics directly into a blood clot
Intra-arterial thrombolytic administration
Measures to prevent complications of stroke
- VTE prophylaxis
- Management of BP
- Control of stroke risk factors to prevent recurrence
Complications
! Hemorrhagic transformation can be life threatening
- Cytotoxic edema
- Weakness or paralysis
- Disorders of speech d/t facial muscle or CN weakness
- Apraxia (difficulty w/skilled movement) [from inj to frontal & temporal lobes]
- Depression [d/t right hemisphere involvement]
Hemorrhagic Stroke (3 subtypes)
- Nontraumatic subarachnoid hemorrhage (SAH)
- Intracerebral hemorrhage (ICH)
- Intraventricular hemorrhage (IVH)
Medical & surgical management
- Cerebral vasospasm occurs in approx 30% of pts w/SAH & causes narrowing of blood vessel segments
- Surgical evacuation of a hematoma below the tentorium, infratentorial, is gen rec b/c of risk of brainstem compression & irreversible brain inj
?
Is thought to occur as a result of an inherent weakness or gradually acquired weakness of the medial layer in a segment of a blood vessel
cerebral aneurysm
?
Is typ c/b a ruptured aneurysm (weak, dilated vessel) & less commonly by AVM which is a mass of arteries & veins that is not connected by a capillary network
Subarachnoid hemorrhage
?
May also occur as a primary site of hemorrhage
Is typ managed using medical therapies to manage BP & prevent expansion of the hematoma as well as therapies to reverse coagulopathy & treat IICP (e.g., osmotic therapy, hyperventilation, drainage of CSF)
Intraventricular hemorrhage
Administration of ____, a calcium channel blocker, improves outcomes in pts experiencing vasospasm; h/e, this drug is assoc w/hypotension, which may necessitate alteration in dosing by inc the freq of dosing & dec the dose or discont the therapy in some instances
nimodipine
Hyponatremia is a common complication in pts w/SAH, which may be c/b SIADH or by cerebral salt wasting synd, aka renal salt wasting synd
- Myocardial ischemia & infarction, ARDS
?
Localized cerebral ischemia that causes neurological deficits lasting <24 hrs (usually <1-2 hrs)
Causes: inflammatory arterial dz (vasculitis), sickle cell anemia, atherosclerosis, thrombosis, emboli
“warning sign”
Transient ischemic attack (TIA)
Visual deficits
- Blurred vision
- Diplopia (double vision)
- Blindness in 1 eye
- Tunnel vision
Mobility (motor) deficits
- Weakness (facial droop, arm or leg drift, hand grasp)
- Ataxia (gait disturbance)
Sensory perception and speech deficits
- Numbness (face, hand, arm, or leg)
- Vertigo
- Aphasia
- Dysarthria (slurred speech)
TIA: Important Factors
- Low blood flow @ a narrow part of a major artery carrying blood to the brain, such as the carotid artery
- A blood clot in another part of the body (such as the heart) breaks off, travels to the brain, & blocks a blood vessel in the brain
- Narrowing of the smaller blood vessel in the brain, blocking blood flow for a short period of time; usually c/b plaque (a fatty substance) build-up
Important facts to keep in mind
- 40% of people who have a TIA will have an actual stroke
- Nearly half of all strokes occur within the first few days after a TIA
- Sx’s for TIA are the same as for a stroke
There are 2 main types of stroke
What are they?
Ischemic & hemorrhagic
? stroke
Results from a rupture of a vessel within the brain tissue or within the subarachnoid space
Hemorrhagic
? stroke
Occurs when the blood to a part of the brain is interrupted or totally occluded
Result from cerebrovascular obstruction by thrombosis or emboli
Ultimate survival of brain tissue depends upon the length of time it is deprived plus the amt of brain tissue affected
May be referred to as thrombotic or embolic stroke
Ischemic
___ stroke
Hemorrhagic
___ stroke
Embolic
___ stroke
Thrombotic
Major types of stroke
Thrombotic / Embolic / Hemorrhagic
Ischemic: ____
- Forms outside the brain - traveling from another area
> Freq sites: bifurcations of vessels particularly MCA - Cardiac dz - rheumatic heart dz, heart valve dz, >MI [cardiogenic embolic]
> Left heart chambers; afib
> Carotid arteries - Younger
- Sudden & immediate
- Maximum deficits
Embolism
Ischemic: ____
- Atherosclerosis
- Platelet aggregation
- Stenosis
- Occlusion of large cerebral vessel
- Hypertensive
- Clinical manifestation progresses gradually
- Sleeping or upon awakening
- Can present as a TIA (stroke-in-evolution)
Thrombosis
Hemorrhagic
Can be intracerebral (ICH) in the brain tissue or subarachnoid (SAH) bleed b/t brain layers pia mater & arachnoid
- subarachnoid: rebleeding before surgery (!)
! Occurs when a cerebral blood vessel ruptures
- Rupture of blood vessel
- Cause: HTN, aneurysm, trauma, AVM, anticoag, blood dyscrasias, drug abuse
- Sudden, quick, or gradual - caused by HTN
- Focal deficits: severe
- Permanent deficits
! Often fatal
Intracranial hemorrhage
- HA (worst of one’s life)
- Meningeal irritation; neck pain - nuchal rigidity
- Light intolerance
- N/V
- Hemiplegia
- Dec LOC
- Seizures
Hemorrhagic Stroke
! Massive hypertensive hemorrhage rupturing into a lateral ventricle of the brain
Immediate general assessment & stabilization diagnostics
1st: general assessment
> Assess abc’s, VS
> Provide O2 if O2 sat <94%
> Obtain IV access & perform labs
> Conduct assessments
> Check glucose; treat if indicated
> Obtain 12-lead ECG
> Perform neurologic screening assessment
> Order emergent CT w/o contrast
Then: neurological assessment
- Review pt hx
- Establish time of sx onset or last known normal
- Perform neurologic stroke exam (NIHSS)
5 most common sx’s
- Sudden confusion or trouble speaking or understanding others
- Sudden numbness or weakness of the face, arm, or leg
- Sudden trouble seeing in 1 or both eyes
- Sudden dizziness, trouble walking, or loss of balance or coordination
- Sudden severe HA w/no known cause
Stroke Nursing Management
- Primary assessment is focused on cardiac status, respiratory status, & neurologic assessment
If the pt is stable, obtain description of the current illness
> Pay special attention to sx onset & duration, nature, & changes
If stable, obtain
- H/o similar sx’s previously experienced
- Current rx’s
- H/o risk factors & other illnesses (e.g., HTN)
- Fhx of CVA or cardiovascular dz
CVA Awareness: tPA can be given within 3 to max 4.5 hrs onset UNLESS if pt is in 1 of these categories
✦ >80
✦ Anticoagulation regardless of INR
✦ Imaging evidence of ischemic injury involving more than 1/3 of the brain tissue supplied by the MCA
✦ Baseline NIHSS score >25
✦ Hx stroke & DM
2° assessment incl comprehensive neurological exam
- LOC (incl NIHSS)
- Cognition
- Motor abilities
Comprehensive neurologic exam
- CN function
- Sensation
- Proprioception
- Cerebellar function
- DTRs
Many conditions can mimic strokes !
H: Hypoglycemia (& hyperglycemia)
E: Epilepsy
M: Multiple sclerosis (& hemiplegic migraine)
I: Intracranial tumors (or infections, like meningitis, encephalitis, & abscesses)
The area of insult will determine what the sx’s & deficits will be
?
- vision
occipital lobe
?
- movement
- intelligence
- reasoning
- behavior
- memory
- personality
frontal lobe
?
- balance
- coordination
- fine muscle control
cerebellum
?
- breathing
- BP
- heartbeat
- swallowing
brain stem
?
- intelligence
- reasoning
- telling right from left
- language
- sensation
- reading
parietal lobe
?
- speech
- behavior
- memory
- hearing
- vision
- emotions
temporal lobe
?
Is the area responsible for sensory speech
Wernicke
?
Is the area responsible for motor speech
Broca
Manifestations of Right & Left Brain Stroke
Left Hemisphere Stroke
- Agraphia, acalculia
- Alexia (word blindness)
- Anxiety
- Aphasia
- Depressed, quick frustration
- Disorganized
- Intellectual & (poss) memory impairment
- Right hemiparesis/hemiplegia
- Slow, cautious behavior
Right Hemisphere Stroke
- Unilateral neglect
- Poor attention span
- Overestimate their abilities (risk for injury)
- Loss of depth perception
- Poor impulse control
- Poor judgment
- Left hemiplegia/hemiparesis
- Hemianopsia (loss of half of the visual field)
- Impaired sense of humor
- Inability to recognize faces
- Loss of ability to hear tonal variations
Cognitive: Aphasia
- Wernicke’s
- Broca’s
- Global
?
receptive or expressive?
- Motor
- Frontal lobe
- Poor articulation
- Slow
Broca’s
expressive
?
expressive or receptive?
- Sensory
- Temporal lobe
- No comprehension
- Lacks content
- Neologisms
Wernicke’s
receptive
?
- Repeat the same sounds
- Poor comprehension
! A few words @ a time & severe difficulties from communicating effectively
Global
Clients become @ risk for injury/self care deficits
Nursing Interventions: Impaired Verbal Communication
✐ Speech therapy; speak @ a slower rate
✐ Listen carefully; take cues
✐ Anticipate needs; picture board; point to objects & say
✐ Keep it simple; repeat command
✐ When changing topics - tell pt change the topic
✐ Calm reassurance
✐ Demonstrate actions
?
Is disturbed recognition of familiar objects
Agnosia
Also, incontinence - may have altered bowel & bladder control
?
Inaccurate relay of instructions to body
Apraxia
When the lesion affects the right middle cerebral artery (RMC), that’s the right hemisphere; eye deviation toward side of insult
Motor exam tells us about which part of the brain is involved
___ means weakness of 1 side of the body. So, the paralysis or weakness is contralateral to the side affected
___ is paralysis on 1 side of the body
Hemiparesis
Hemiplegia
Left hemiplegia/paresis is a ___ brain insult
Right hemiplegia/paresis is a ___ brain insult
right
left
Hemiparesis occurs w/the MCA, ICA, & the anterior cerebral artery (ACA)
H/e, w/the MCA arm weakness is expected to be greater than leg weakness
W/ ACA leg weakness is > arm
- Doesn’t affect thorax & abdomen
?
Happens when a stroke causes weakness of the muscles 1 uses to speak
May affect muscles used to move the tongue, lips, or mouth, control the breathing when speaking or producing voice
Dysarthria
- Doesn’t affect ability to find the words to say or to understand others, unless they have other communication problems @ the same time
- The voice may sound different & they may have difficulty speaking clearly
- Voice sounds slurred, strained, quiet, or slow
?
CN involved in chewing ability
V
?
Cranial nerve involved in facial paralysis/paresis
VII
?
CN’s involved in swallowing ability (2)
IX, X
Dysphagia involves which CN’s? (4)
V, VII, IX, XII
Nursing Interventions
✐ Early mobilization; reposition frequently, skin inspection
✐ Freq ROM exercises
✐ Bed exercises
✐ Sit for short periods of time
✐ No pillow under affected knee
✐ Prone position for 15-30 min/day
✐ No foot pressure
✐ Trochanter roll - prevent external hip rotation
✐ Pillow under axilla / splints
✐ Assess for manifestations of aspiration
✐ Maintain airway
✐ Suction on hand
✐ Nutritional consult, progressive feeding program
✐ Remain w/pt during meals
✐ Upright position
✐ Place food on unaffected side
✐ Head tuck position
✐ Small servings
✐ High nutritional supplements/enteral feeding
Stroke: Visual Deficits
- Homonymous hemianopia
- Impaired depth & visual perception
Psychosocial: Behavioral Changes
Frontal lobe / anterior cerebral artery
- Memory loss
- Poor judgment
- Loss of abstract thinking
- Loss of inhibition & emotion
- Emotionally labile
- Depression
Treatment: Hyperacute Phase - Ineffective Tissue Perfusion
Goal:
- Early detection & recognition
- Maintain cerebral perfusion
Ischemic Treatment: Restore cerebral blood
____
- Given within 3 hrs of sx’s onset
Exclusions - - Score from the NIHSS >25
- Systolic BP <185, diastolic <110
>80 y.o.
! H/o stroke & DM
INR ≤ 1.7
Recombinant tissue plasminogen activator (RT-PA)
Complications of RT-PA
- Bleeding
! Watch for signs of intracranial hemorrhage
- New complaints of a HA
- N/V
- Sudden change in lvl of consciousness
- Assess for systemic bleeding
> Change in LOC, tachycardia, hypotension, cool clammy skin
! Stop the infusion !
Prevent Complications
- Neurological stroke assessment
- Ongoing BP management
- Monitor for cerebral edema
- Assessment of oxygenation
- Continuous cardiac monitoring
- BG monitoring: hyperglycemia
- Management of temperature
- Monitor/manage seizure
- Monitor/manage vasospasm
↑ ICP: Early signs
- Restlessness, confusion, HA, visual disturbances, pupillary changes (slow response)
Late signs
- Dec LOC, ↑ systolic BP, ↓ diastolic BP, fever
- Pupils (can be non-reactive, fully blown)
Management of ↑ ICP
- Bed rest, HOB 30°
- No flexion of the neck/hip
- Keep BP lowered
- Control fever
- Reduce cellular demand - propofol
- No valsalva maneuver
- Total nursing care
- External ventriculostomy drainage
- Mannitol
- Surgical evacuation
Prevent Recurrence
Anticoagulation
- Heparin
- Warfarin
Antiplatelet agents
- ASA
- Ticlopidine
- Clopidogrel
- Dypyridamole
Surgical Intervention: Carotid Endarterectomy
Post-procedure
- Monitor VS
- Assess for bleeding & hyperperfusion
Post-op Care
- Maintain airway - edema
- No neck flexion
- HTN or hypotension alert!
> Neuro assessment: particular attn to CN’s - VII (facial)
- X (vagus)
- XI (spinal accessory)
- XII (hypoglossal)
