Cerebral Vascular Accident/Test 3 Flashcards
Stroke:
- Third most common cause of death in the US and Canada
* After a stroke, nearly 25% will die within a year
Stroke/CVA/Brain attack occurs when
There is ischemia to a part of the brain or hemorrhage into the brain that results in death of brain cells.
The goals of stroke/cva/brain attack are:
-early recognition of s/s, dx&tx within 3 hours of onset, increase cerebral blood flow and reverse the ischemic process to the viable brain cells
Transient Ischemic Attack:
A temporary focal loss of neurologic function caused by ischemia of one of the vascular territories of the brain; lasts less than 24 hours and often less than 15 minutes
Risk factors for stroke/cva/brain attack. Nonmodifiable:
- Age
- gender
- men more likely to have stroke
- women more likely to die from it
- Race
- Hereditary
- Atherosclerosis
- thrombus formation contribute to emboli
Risk factors for stroke/cva/brain attack.
Modifiable
- Hypertentions-single most important modifiable risk factor
- Heart disease-a-fib, MI, cardiomyopathy, cardiac valve abnormalties and cardiac congenital defects
- Diabetes
- Cholesterol
- Smoking
- Excessive alcohol use
- Obesity
- Physical inactivity
- Poor diet
- Drug abuse
- Oral contraceptives
Warning signs of a stroke: FAST
Sudden onset:
- Face- weakness, numbness or loss of sensation on one or both sides of the body
- Difficulty speaking or understanding speech, confusion
- Severe headache, occuring without apparent reason or different from usual
- Dizziness, loss of balance or coordination, falling, unsteady gait without apparent reason
Pathophysiology of stroke:
Blood is supplied to the brain by 2 major pairs of arteries
- the internal carotid arteries (anterior circulation)
- the vertebral arteries (posterior circulation)
- Circle of willis unites the anterior and posterior circulations
- Auto regulation maintains blood flow at a rate of 750 ml/min
Anterior Cerebral Artery:
Supplies most of the medial surface of the cerebral cortex (anterior 3/4) frontal pole via cortical branches and anterior portions of the corpus callosum. Perforating branches (including the recurrent artery of Heubner and Medial Lenticulostriate arteries) supply the anterior limb of the internal capsule, the inferior portions of head of the caudate and anterior globus pallidus . Bilateral occlusion of anterior cerebral arteries at their stems results in infarction of the anteromedial surface of the cerebral hemispheres (SEE SLIDE)
Stroke Types
Ischemic
Hemorrhage
Ischemic stroke
A clot blocks blood flow to an area of the brain
Hemorrhage stroke
bleeding occurs from inside or around brain tissue
CT Scan will
indicate size and location
*differentiates between ischemic or hemorrhage
Clinical distinction between meningitis and encephalitis is based on
brain function
Meningitis
uncomfortable, lethargic, disctracted by headache but cerebral function remains normal
Encephalitis:
abnormalties in brain function are common, including altered mental status; motor or sensory deficits; speech/movement disorders
Ischemic stroke:
80% of all strokes
-inadequate blood flow from partial or complete occlusion
Thrombotic stroke
- injury to a blood vessel wall
- formation of a blood clot
- narrowed blood vessel lumen
- if it becomes occluded, infarction occurs
Embolic Stroke:
- embolus lodges in and occludes
- resulting in infarction
- What dysrhythmia predisposes patients to an embolic stroke-
Hemorrhagic stroke:
*bleeding into the brain tissue, subarachnoid space, or ventricles
Intracerebral hemorrhage
- caused by vessel rupture
* poor prognosis
Subarachnoid hemorrhage
*bleeding into the cerebrospinal fluid-filled space between the arachnoid and pia mater commonly caused by rupture of aneurysm
Clinical Manifestations
- Remember two vessels most often affected middle cerebral artery and the internal carotid artery
- Thrombus formation occurs during sleep or rest most of the time
- Symptoms may develop abruptly or progress slowly over a period of time
- Symptoms peak in 72 hours after the event specific symptoms reflect the site and severity of ischemic damage
Common clinical manifestations
- Intellectual function
- Personality and Affect
- Motor activity impairment
- Diminished sensation
- Altered spatial perception
Common clinical manifestations: Anosognosia
Apparent unawareness or denial of any loss or deficit in physical function.
Loss of proprioceptive skills:
Lack of awareness of where various body parts are in relation to each other and the environment
Agnosia
Inability to recognize a familiar object by use of the senses
Apraxia-
Loss of ability to carry out a learned sequence of movements. i.e., dressing, brushing teeth, combing hair
Spacial relationships
Loss of ability to judge distance or size or localize objects in space
Bowel and bladder
Frequency, urgency and urinary incontinence. Potential for bladder retraining if cognitively intack. Neurogentic bladder: frequency and urgency.
Unilateral lesion:
partial sensation and control of bladder
Brain stem:
bilateral damage and the loss of control of urination/constipation r/t immobility
Motor:
Hemiparesis or hemiplegia on the opposite side of the ischemia site- initially flaccid then progresses to spastic
Dysphagia
Swallowing reflex may be impaired-pt will pocket food on the effected side
Dysarthria
difficult and defective speech d/t impairment of the tongue or other muscles (pharynx, facial muscles) essential to speech. Slurred speech/garbled. Mental function is intact. May be unable to speak but no deficit in the ability to understand, read or write.
Aphasia:
total loss of comprehension and use of language
Dysphasia
difficulty related to the comprehension or use of language
Expressive motor: Nonfluent
Broca’s area (Left frontal)
-loss of power to express self by: speech, writing, unable to combine speech sounds into words
Receptive Sensory: Fluent
- Wernickes area (left temporal)
- difficulty or inability to comprehend speech
- alexia: inability to understand the written word
- agraphia- inability to express self in writing
Most difficult consequence for familites
Aphasia
Motor:
Hemiparesis or hemiplegia on the opposite side of the ischemic site
- initially flacid then progresses to spastic
- respiratory function
- apraxia-performing learned movements.
- *self-care abilities
- swallowing (dyphagia) & gag reflex.
Visual disturbances:
*Remember that the right brain is responsible for processing light coming from the left visual field and vice-versa-thus a lesion in the right visual pathway distal to the chiasm produces deficit of the left visual field. Blindness of nasal half of the visual field of one eye and temporal half of the other eye. Left or right side of corresponding side of both eyes. Need to teach pt to turn head and eyes toward direction of deficit and scan the whole room and pay attention to that side of the deficit.
-decreased visual acuity
-diplopia
-homonymous hemianopia
,,,blindness of corresponding side of both eyes
Unilateral Neglect:
Complex disorder which varies on the cause of damage and severity. A neurological disorder in which patients display a paucity of response to stimuli that appear contralateral to the side of the lesion. Neglect is more often associated with the right hemisphere damage, especially when this damage includes the regions of the inferior parietal lobule and/or the temporal-parietal junction. It may also occur, however, after damage to other brain structures.
Acute Stroke: Goals
Preserving life-ABC's-preventing further brain damage reducing disability -HTN common immediately after a stroke. -A&B- respiratory system is a nursing priority --airway protection and aspiration pneumonia risk --CO2 monitoring C: Promote perfusion --fluid and electrolyte balance --adequately hydration D. Neurologic status: --monitored closely to detect changes --Increased ICP --Vasospasm
Acute phase: treatment depends on type of stroke:
- Reperfusion Therapy (tPA)- tissue plasminogen activator
- Surgery- Evacuation if bleed larger than 3 cm
- coiling
- MERCI- mechanical embolus retrieval in cerebral ischemia
- *Salvage brain tissue
- *Restore cerebral perfusion
- *Prevent increased ICP
- *Prevent cerebral ischemia
In acute phase: additional problems
- Respiratory problems
- Urinary infections
- Disuse complications
- skin breakdown
- deep vein thrombosis
- muscle atrophy
- joint contratures
Treatment
- Reperfusion therapy
- tPA
Surgeries
- Carotid ndarterectomy- goal is to resestablish adequate cerebral blood flow
- Transluminal angioplasty
- Stenting
- Clipping
- Coiling
Greatest risk during surgery is
compromised cerebral blood flow.
Potential complications from surgery
- Hoarseness
- Dysphagia
- CVA
- Vasospasms
- B/P
Post operative managment
*VS-except unstable b/p for the first 24 hrs.
*Monitor for comlications-frequent neuro checks, particularly facial and vagus Cranial VII & X
*Monitor for dysrhythmias and assess for chest pain
*Monitor for signs of reperfusion therapy
-worsening or recurring stroke symptoms
*Signs of increased ICP
*Monitor for incision site for patency and drainage
*Assess for hoarsness and dyphagia
Report immediately Cranial XII and IX
*Assess for trachea midline
Rehabilitation:
The process of maximizing the patient’s capabilities and resources to promote optimal functioning related to physical, mental, and social well-being
After the stroke has stabilized for 12 to 24 hours, collaborative care shifts from preserving life to prevention of re-occurence
- Anti-platelet drugs (aspirin/plavix)
- Anticoagulants
- Lessening disability
- Attaining optimal function beginning with ROM, progressing with OT/PT, etc.
Nursing Management: Planning
- Maintain a stable or improved LOC
- Attain maximum physical functioning
- Attain maximum self-care abilities and skills
- Maintain stable body functions e.g. bladder control
- Maximize communication abilities
- Maintain adequate nutrition
- Avoid comlications of stroke
- Maintain effective personal and family coping.
Warning signs of stroke:
- Sudden weakness, paralysis, or numbness of the face, arm, or leg, especially on one side of the body
- Sudden dimness or loss of vision in one or both eyes
- Sudden loss of speech, confusion, or difficulty speaking or understanding speech
- Unexplained sudden dizziness, unsteadiness, loss of balance or coordination
- Sudden severe headache
