Week 10: NEUROCOGNITION II Flashcards
Stroke
- 3rd leading cause of death in Canada
- Acute: Disruption of perfusion of O2 and nutrients to cerebral tissues
Types:
- Ischemic – blocked vessel 80%
- Hemorrhagic – bleed 20%
- Transient Ischemic Attack (TIA) – neurological dysfunction that resolves
without imaging evidence of infarction
Pathophysiology: Stroke
Decreased blood flow to the brain due to thrombus/clot (occlusion) or blood vessel rupture (hemorrhage)
Decreased perfusion causes brain cells to be starved of O2, leading to neurological deficits
If not resolved, cell death from prolonged ischemia leads to severe deficits or death
Entire cascade can also lead to cerebral edema
Risk factors: Stoke
Age 55+ (doubles every 10 years after)
Men at risk for stroke, women at higher risk for mortality
Family members
Prior stroke/TIA
HTN, A fib, diabetes, sleep apnea, dyslipidemia
Substance use (vasoconstriction, increased HR)
Obesity
Physical activity
Smoking, alcohol use
Diet
Stress/depression
Oral contraceptives
Ischemic Stroke
Disrupted blood flow to the brain due to thrombus/clot (occlusion)
- Classifications:
Large artery (BAD) – atherosclerotic plaque formation leads to occlusion, brain perfusion is interrupted
Small artery – emboli, high BP, vasospasm
Cardiogenic embolic – clot from heart goes to brain (Afib)
Cryptogenic – idiopathic (no known cause)
Nursing assessment: Ischemic Stroke
Health history:
Experience of stroke symptoms, VS, LOC
- FAST – face, arms, speech, time
Physical assessment:
ABCs and LOC
Neuro:
Motor deficits
Sensory deficits
Cognitive and verbal deficits
Seizure activity?
Labs and Investigations: Ischemic stroke
Imaging – immediate non-contrast CT or MRI
4.5 hours eligible for thrombolysis
6 hours eligible for endovascular thrombectomy
Can differentiate between ischemic versus hemorrhagic
Medical interventions: Ischemic Stroke
Thrombolysis:
- Fibrinolytic therapy: tissue Plasminogen Activator (tPA) – must be given within 3 hours to dissolve clot
- Anticoagulants – prevent further clots
Endovascular thrombectomy
- Removal of a thrombus under image guidance
Left versus Right Sided Stroke
Left: (speech and language)
Right sided paralysis
Speech issues
Language issues
Memory loss
Slow and cautious
Right sided neglect
Right: (safety risk)
Left sided paralysis
Vision issues
Memory loss
Fast and risky
Left sided neglect
Hemorrhagic Stroke (bleed)
Intracranial:
- Bleeding into brain tissue due to ruptured vessel (tumour, atherosclerosis, etc.)
Subarachnoid:
- Bleeding into subarachnoid space (aneurysm, arterial wall weakness, AVM)
- Results in:
Blood compressing brain tissue increases ICP and causes cerebral edema
Nursing assessment: Hemorrhagic Stroke
Health history:
Rapid onset
Severe headache (splitting)
Nausea/vomiting
Confusion, altered LOC
One-sided weakness
Impaired speech
Fixed pupils
Physical assessment:
Abnormal neuro findings
Weakness – declining motor function
Lethargy, LOC, seizure, coma
Pupil changes and no blinking
Hemodynamic instability (increased BP, decreased HR)
Respiratory distress
Vomiting (w or w/o nausea)
Labs and investigations: Hemorrhagic Stroke (bleed)
Immediate non-contrast CT or MRI
Medical interventions: Hemorrhagic Stroke
Endovascular procedure – use a catheter to repair vessel wall from the inside
Surgical procedure – done outside of the vessel
Nursing Management of Stroke
- Manage ABCs
o Monitor swallowing – aspiration risk, usually NPO
o HOB at 30 degrees – reduces aspiration risk
o Oxygenation
o Blood pressure
o Fluids for perfusion - Manage increased ICP
o Cerebral edema/blood in cranial cavity
o Osmolar diuretics – mannitol
o Increase osmolality of blood – draws fluid from brain
o Increase fluid volume in intravascular space, then use diuretics to excrete
o Caution – electrolyte imbalance and seizures
o Elevate HOB – flat/high fowlers may increase ICP
o Low stimulation environment - Manage interventions
o Reperfusion
o Surgery – remove clots or repair hemorrhage o Medications
Stroke Rehabilitation
Residual deficits:
o Motor
o Dysphagia
o Incontinence
o Aphasia
o Cognitive changes
Nursing Management: Post-Acute Stroke
- Cerebral vascular risk factor modification:
o Healthy balanced diet (reduced cholesterol, high fiber, low sodium)
o Physical activity
o Weight management
o Smokingcessation
o Alcohol use - New medications
o Antihypertensives
o Lipid management (statin)
o Diabetes management
o Antiplatelets
Anticoagulant therapy
Seizure pathology
- Healthy brain – balance of excitatory neurons releasing glutamate, inhibitory release GABA
- Brain during seizure – increased excitatory neurons releasing glutamate, less inhibitory releasing GABA
Seizure Disorders
Seizures are excessive and acute-onset electrical activity of cerebral neurons causing
abnormal motor, sensory, autonomic, and/or psychiatric activity
- Epilepsy – two unprovoked seizures occurring 24 hours apart
- Numerous causes
Underlying Causes of Seizures
- Electrolyte & metabolic imbalances (blood glucose, acidosis, fluid deficit)
- Drug toxicity
- Brain tumours
- CNS infections
Seizure Triggers
- Stress
- Trauma
- Overexertion
- Period/pregnancy
- Sleep loss
- Visual disturbances, sounds, smells
- Recreational drugs
- Alcohol use
- Undermedicated w anticonvulsants
Prodromal seizure
Before seizure activity
- May follow exposure to a trigger
Most common symptoms: confusion, anxiety, irritability, headache, tremor,
anger, mood disturbances
Aura seizure
Warning felt before seizure
Focal aware seizure that precedes a generalized seizure
Most common symptoms: visual disturbances, cognitive disturbances (eg.
feelings of déjà vu)
Ictus seizure
Seizure activity
Important to measure duration
Post ictus
From end of seizure to return of client to baseline
Altered LOC, state of inhibition
- Poverty of speech, motor impairment, memory, lethargy/drowsiness, confusion, delirium, psychosis
- S&S depend on location and type of seizure
3⁄4 of clients with epilepsy experience postictal symptoms
Hours to days to resolve deficits
Focal Onset Seizures
Aware (simple)
Referred to as aura
Motor: jerky movements
Non-motor:
- Sensory
- Autonomic: bp, bowel/bladder control
- Psychiatric: cognition disturbances, anxiety, fear
Impaired Awareness (complex)
Motor: Jerky movements
Non-motor:
- Sensory
- Autonomic: bp, bowel/bladder control
- Psychiatric: cognition disturbances, anxiety, fear
Status Epilepticus
Seizure that lasts longer than 5 minutes OR a seizure within 5 minutes after returning to
baseline – emergency (possible brain damage)
- Causes:
- Uncontrolled epilepsy
- Stroke
- CNS infections
- Fever
- Electrolyte imbalances o BG imbalances
- Alcohol withdrawal
- Treatment:
- Treat cause, give antiseizure meds
Pharmacological Interventions
- Anticonvulsant medications
- Daily – routine blood work monitoring, take same time every day, do not stop abruptly, can interact with one another
- Emergency medications
Surgical Treatment of Seizure Disorders
Focal resection – part of brain is removed
Hemispherotomy – hemispheres of the brain are disconnected
Corpus callosotomy – corpus collosum is disconnected between the right and left
hemispheres of the brain
Vagal nerve stimulator – implantable device stimulates the vagus nerve to prevent
seizures
Nursing Management: Seizures
- Seizure precautions if known epilepsy or risk factors
- Suction and O2 at bedside
- IV access
- Padded bedrails
- Pillows
- Bed in lowest position
- Remove objects likely to cause injury
- Call for help – ABCs
- Administer meds (know orders)
- Clear area of hazards
- Time the phases of seizure, monitor symptoms
- If safe, turn client on side (aspiration prevention)
- Do not restrain client
Postictal:
- Maintain side-lying related to LOC
- Suction secretions
- Reorient to environment
- Low stimulation environment
- Frequent neuro assessments
