Stroke Flashcards
Cerebrum
Frontal love - motor function, provlem solving, high level thinking
Temporal - memory, hearing, speech
Parietal - sensation, space
Occipiral - Sight
Contralateral processing
Information of each hemisphere is responsible for the opposite sside of the body!!!
Other parts of the body anatomy
Cerebellum - fine motor movements
Brain stem - HR, BP, respiratrion, 10 cranial nerves, essential for life
Thalamus - sensory
hypothalamus - smooth muscle, HR, digestion, senses, hormones, body temp
Ventricles - cavities in the brain filled with CSF
Cerebral spinal fluid/CSF - Clear fluid that provides cushioning for the brain and spinal cord
Meninges - 2 protective layers (dura mater, arachnoid mater, pia meter), csf between arachnoid and pia
Blood brain barrier - wall between capillaries and brain tissue
Cerebral circulation = internal carotid arteries and vertebral arteris
Regulation of cerebral blood flow
Continuous need for oxygen and glucose as the brain cannot store glucose
Cellular death occurs if 5 minutes of no flow
Effected by
1) Systemic BP
2) CO
3) Blood thickness/viscosity
4) Intracranial pressure (ICP)
Autoregulation of the brain
Protective mechanism that the brain can regulate its blood flow despire systemic blood pressure
Has limits
Carbone dioxide =
High - vasodilation (get rid of it)
Low - Vasoconstriction
Oxygen
Low = Vasodilate (to get more of it)
pH =
Low= Vasodilates (get rid of the CO2)
Collateral circulation
Sometimes the brain can receive blood from different blood vessels
Stroke
Ischemia or hemorrhage = death of cells
Note that the skull is rigid so the brain doesn’t have space to expand when ICP is high
Ischemic stroke
Most common due to to inadequate blood flow to the brain
Penumbra
Zone of borderline with ischemic tissue
= Reversible tissue that can be saved within 3 HOURS window of opportunity
not that Swelling occurs with cell death, damage seen in 3 days as macrophades infiltrate and eat away necrotic tissue and cause scarring
1) Transient ischemic attack (TIA)
temporary ischemia, warning sign that a larger stroke can occur
Usually lasts less than 1 hour, but can last longer
Usually due to carotid stenosis (artherosclerosis) and atrial fibrilatio
2)Thrombotic
Blood clot in cerebral artery that causes occlusion/block caused by atherosclerosis
Symptoms progress within 72 hours
3) Embolic
Thrombus breaks off and travels to the brain
Commonly from heart issues - mitral valve, endocarditis, atrial fib, rheumatic heart disease - but can be from fat embolus, air embolus, tumor, bacterial clump etc.
- Afib - contraction of atria causes pooling and clots to form
- Infective endocarditis causes inflammation and clumps of bacteria
Sudden onset - faster occurrence than thrombotic
Hemorrhagic stroke
Skull is rigid, therefore only certain amount of blood tissue and CSF can flow
Bleeding causes compression, swelling, ischemia, ICP and necrosis
1) Intracerebral hemorrhage
Bleeding due to ruptured vessel
Rosk factors = HTN, brain trauma, meds like anticoagulants
Sudden onset, usually during periods of activity
Worst HA ever
Subarachnoid hemorrhage
Bleeding into subarachnoid space, more common
Commonly due to ruptured aneurysm - weakening of artery that stretches like a ballon and bursts
More common in women
NA, stiff neck, seizure, nausea
Hematoma
Bleed that already clottes and slowed, whereas hemorrhage is current active bleedings
Stroke risk factors
Atheroscleorsis
Genes - like high cholesterol
Age
Ethniciy - HTN, diabetes
Hypercholestelemia
Smoking
Diabetes
Obesity
Stress (increases SNS)
Substance abuse - cocaine etc. cause arterial spasm and cerebral vasospam
Alcohol - liver, clotting factors
Meds
Atrial fib = embolic stroke
Prengnacy and estrogen replacement
TIA
Arteriovenous malformation (AVM)
Congenital abnormalities, genetic predisposition where abnormal entanglement o fblood vessels = usually aymptomatic but can burst
Acute stroke & ICP
Acute
Sudden numbness/hemiplegia, confusion, slurred speech, vision, severe HA, vomiting
ICP
HA/vomiting, LOC, seizure, posturing, pupil change
Clinical manifestation
1) Motor deficit
Mobility, resp, speech. swallowing, gag reflex
Hemiplegia - paralysis of half the body
Hemiparesis - weakness of half the body
Akinesia - impairment of voluntary movement
Hyporeflex/hyperreflexia (hyper can occur after hypo)
ii) Communication
Aphasia - loss of both receptive and expressive
Expressive/Broca - Pt wants to express themself but cannot and are aware of it
Receptive/Wernicke - can speak but doesn’t make sense
Dysphasia - difficulty speaking
Anomic aphasia - mild formwhere dififfculding naming
Dysarthria = disturbance of muscle that control speech
iii) Cognition
Memory, impulse or overly caution, short attentive span
iv) Spatial
Anosognosia - awareness of own body parts/disease
Unilateral neglect = eg. drawing clock, copies only one side
Homonymous hemianopia = blindness of half they neglected
Agnosia = difficulty recognizing objects
Apraxia = inability to carry out learnt movements
v) Elimination
immobility - constipation, retention, etc.
Stroke complication
Aspiration pneumonia, DVT, UTI, falls, dehydration, constipation, depression, seizures
Atorvastatin (Lipitor)
HMG- inhibitor
Increases the receptors on hepatocytes to bring in LDL
Decreases by 2 weeks, but effects go away when drug is stopped
Generally well tolerated, occasional HA, dizzy, GI, rash
Rare hepatoxicity
Rare Myopathy/Rhabdomyolysis (kidney)
Dose in the evening
LFT, Urea/creatinine, CK
Aspirin
NSAID for prevention of stroke and treatment for only ISCHEMIC
Inhibits thromboxane A2 to prevent platelet aggregation
AE
Heartburn, nausea - take full glass of water/food
GI bleed risk, bleeding risk (discontinue 1-2 weeks before surgery)
PPI prophylaxis
NC
Risk of GI bleed, CVD - hypotension, tachy, weak, pallow, bleeding gum, melena, CBC etc
Renal function
MUST BE USED WITHIN 48 HRS OF ISCHEMIC STROKE
Labetalol
Beta blocker that is VERY potent
Block beta 1 and 2, IV only
AE
Fatigue, weakness, orthostatic hypotension
Pulmonary edema, bradycardia, bronchospasm, congestive HF
NC
Administer w meals if PO
Frrequent BP and pulse = hold is les than 40 bpm of apical
PT MUST STAY SUPINE FOR 3 HOURS
Assess vitals every 5-15 minutes
High alert
NC
Abrupt withdrawal = life threatening arrythmia. HTN, MI
Change position very slowly
Hypoglycemic unawareness
Blood pressure and stroke
Ischemic (TPA) = 185/110
Ischemia (Non-TPA) = 200/120
Hemorrhagic = keep between 140-160
Tissue Plasminogen Alteplase (TPA)
Thrombolytic
NOT FOR HEMORRHAGIC STROKE!!
Moa - binds to fibrin to break down clot
AE
Bleeding!!!!
NC - Always confirm its ischemic with CT before
Must administered between 3-4.5 hours of symptom onset (door to kneedle should be under 60 min)
Before giving make sure to get history, blood work, CT scan, hold all anticoagulants/antiplatelet for 24 hr
Reduce risk of bleeding by avoiding subcut/IM
ABSOLUTE Contraindication
Previous intracranial bleeding or tumors
Active internal pleaded
Suspected aortic dissection
Relative - uncontrolled HTN, anticoagulant use, CPR/surgery less than 3 weeks, recent bleed in 4 week, pregnancy, peptic ulcer
= HIGH RISK OF HEMORRHAGE WHEN USING
Unfractionated heparin
Anticoagulant - increase antithrombin activity
AE
Bleeding
Epidural hematoma
HIT
NC
Monitor VS, aPTT every 4-6 hours, platelet, HgH
Signs of bleeding, CWSM
Antidote - Protamine sulfate!
FAST
- Face
- Arms
- Speech
- Time call 011
Sudeen numbness, slurred speech, blurred vision, dizzy, severe HA
Immediate priorities in acute stroke
Must be completed within 4.5 hours
1) When did onset begin?
2) ABC
- Gag, swallow, cough
- VS - RR, O2, Pulse, BP
3) Rapid neurological assessment
- LOC, GCS, Pupils (PERRLA), arm/leg movement
- Blown pupils = severe brain injyry
4) Blood sugar!!
- Rule out hypoglycemia
- Hyperglycemia occurs in stress
5) Secondary neurological assessment
- Speech, motor, Canadian scale whatever
6) CT scan (hemorrhagic? ischemic?)
7) Treatment
Late bad signs of stroke
Coma, posturing (decorticate/decerebrate), absent motor response, fixed/blown pupils, apneic periods
CVA diagnostics
CT scan, MRI, CTA, etc
Must be done to confirm if ischemic or hemorrhagic (ischemic will be dark coloued, hemorrhagic is bright white)
Blood work
Hgb, platelet, coagulation, glucose, LFT, curea/creatinine, lipid profile
Head to toe
CNS
LOC - GCCS
Speech
gag/swallow/cough
Pipils
Extremities strength
Pronator drift
Cranial nerves
Sensory and motor, cerebellar
CVS
VS, CWSM
Cap refill
DVT, dehydration
Resp
RR, dysphagia, lung sounds, aspiration
GI
Constipation
GU
Urine output
Incontinence, urgency, frequency
Integment
Dry skin, decreased skin turgor, skin integrity
CNS manifestations of stroke
Related to location of stroke
Can effect motor, speech, affect, intellectual function, spatial/perception, sensory
