TIA and Stroke Flashcards
TIA
Transient ischemic attack; acute focal cerebral insufficiency lasting under 24h (often under 60min)
Do TIAs have residual effects?
NO - and no acute infarction
Who gets TIAs
more males than females
Does TIA cause increased risk of stroke?
Yes - inc risk after one within 1 month
Do TIAs recur often?
Yes - often with the same symptoms
TIA CM
depend on the affected vessel and follows a vascular “line”
TIA CM (specifics)
Like Bell’s palsy
- droopy face, like stroke
- carotid area–weak, numb, heaviness in the contralat arm, leg, face, dysphagia and ipsilateral monocular vision loss
- vertebrobasilar–blurry vision, vertigo, dysphasia, motor or sensory changes, ipsilateral face, contralateral body
TIA care
- hx and physical for pattern or vasc problem
- CT, MRI, MRA 1st to r/p hemorr, lacunar infarct or aneurysm
- Carotid doppler study for carotid stenosis
- echo for cardiac causes
TIA tx
- anticoag–ASA or clopidogrel or hep/warf if cardiac
- carotid endarectomy w/ over 70% stenosis
- edu on lifestyle meds
Names for strokes
CVA aka stroke aka brain attack
Risk fx for stroke
HTN, HLD (inc chol), endothelial damage–tobacco and DM, obese, alc, fam, race (AfAm), oral contraceptives, old, men, SCA, physically inactive, arterial disease, hx TIA, a-fib, IV, coke use, HF (EF <25%)
Stroke CM
numb/weak unilaterally in face, arm, leg, confuse, trouble speaking, slurred speech (dysarythria), ataxia, severe HA w/o cause (esp hemorr)
What to do first after a stroke
CT w/o contrast
- bright white shows hemorrhaging blood
- darkness shows damaged tissue
Ischemic stroke
Vessel occlusions stop blood distal to brain occlusion
- occluded cerebral artery
- thrombus or embolus
How to treat an ischemic stroke best?
Known the best cause
Hemorrhagic stroke
Ruptured vessel in brain parenchyma
Hemorrhagic conversion
happens post-stroke, extravasation of blood from peripheral circulation across a disrupted BBB
- occurs after reperfusion is established
- natural or with therapy
Stroke patho
dec blood supply, o2 dec, neuro def and sx w/i 1 min, cont loss of supply, irreversible damage
Thrombotic stroke
from arterial obstruction from thrombus
- often athero that ruptures
- or clot
- or hypercoag state–cancer, oral cont, COVID
Embolic stroke
- often cardiac source like a-fib, mural thrombus
- often arterial on L side
- venous if atrial septal defect or patent foramen ovale
- thrombus of vegetation of valves from mitral valve (IE) and valve replace
- carotid plaque rupture (hear bruit)
What is a mural thrombus
in L ventricle a part breaks off
penumbra
injured but salvagable tissue around dead area
Goal of stroke tx
Tx w/i 3h to save
- maintain perfusion–BP <180/105 w/ TPA; BP <220/120 w/o TPA
What are hemorrhagic strokes associated with
- long standing, severe HTN–inc pressure weakens the vessel
- aneurysms
Mortality of hemorrhagic stroke
quick–minutes to hours or w/i seconds in the brainstem
With a hemorrhagic stroke, ICP…
Increases with inflammation
- herniation can occur
- tissue death
- cranium defines the space
Age range for hemorrhagic stroke
30-60Y (younger than ischemic)
What does hemorrhagic stroke prognosis depend on
Age (older is better), location and size, how rapid the brain shifts occur
Midline shift
blood forces the brain past the cranial midline
Where does a hemorrhagic stroke occur?
Below the pia mater
Epidural bleed
- skull fracture
- arterial bleeds
- less severe injury
subdural bleeds
injury in bridging veins that carry blood from outer region to larger brain vessels
- if severe, rapid decline
- brain moves but vessels don’t
- can be slow–2-10d later (bc venous)
- need to relieve pressure
Where does a subarachnoid hemorrhage occur?
In the CSF
- often due to cerebral aneurysm or AVM
- may see blood in the CSF during a lumbar puncture
Which bleed will NOT be treated by evacuating the blood build up?
Bleeds in the tissue
Hemorrhagic stroke presentation
- worst HA ever
- rapid chx in LOC
- irritation of the meninges–nuchal rigidity and photophobia (subarachnoid)
AVM
abnormal junction with blood flow direct from artery to vein without slowing thru caps
- puts at risk of intracranial hemorrhage
When is a lumbar puncture most sensitive for detecting a subarachnoid bleed?
12 hours after onset of sx
Subarachnoid hemorrhage management
- keep BP steady (withing borders)
- bed rest
- surgery ASAP for aneurysm–clip or coil
- anticonvulsant maybe
- CCB post-surg to “narrow BVs to slow BF”
- triple H therapy for perfusion–HTN (pressors), hypervolemia, hemodilution
When is the risk of rebleed highest?
24 hours after
Fibrinolytics
Destroy an already formed clot
BE FAST
Balance, HA, dizzy
Eyes (vis loss)
Face (symmetry)
Arm (weak)
Speech
Time to call 911
Endovascular embolization
Insert cath in groin and thread to aneurysm and coil metal inside to block blood flow in aneurysm
What is important to know for a stroke?
Last known normal
GCS < 8
Intubate–worry about protecting airway
Stroke protocol
- ABCs
- Glucose and labs
- CT
How do you r/o hemorr or ischemic?
CT scan w/o contrast
tx for hemorrhagic stroke
- Reverse anticoags
- Control HTN
- Manage ICP
- raise HOB, antipyretics, head neutral
tx for ischemic stroke
Anticoags or thrombolytics to dec penumbra
MRI vs CT for stroke
MRI more detailed but not first choice in emergencies
L side head stroke complications
Logic, math, communication
R side stroke comps
Pictures, stories, music, art
Alteplase class and MOA
- fibrinolytic therapy
- Converts plasminogen to plasmin to dissolve clots
Alteplase SE and NC
Biggest risk is intracranial bleeding, dysrhythmias with reperfusion, hypotension
- give w/i 30-70 min for sx of MI
- can give with Hep and clopidogrel
- CI with brain bleed
- IV
- antidote is aminocaproic acid (anti-thrombolytic)–stops the bleed
Surgical tx for ischemic stroke
Penumbra procedure–mechanical thrombectomy
Other comps of stroke
- dysphagia–need swallow study
- motor and sensory
- flaccid on contralat side
- spasticity w/i 6W and contractures
- Contralat vision changes
- aphasia–probs with lang reception of reading, speaking
Homonymous hemianopia
Lose the r or l side of both visual fields
Receptive aphasia
Difficulty understanding but can communicate
Dysarthria
Impaired speech
Expressive aphasia
Can’t express language but can comprehend
Cognitive stroke effects
- memory
- behavioral–apathetic, emotional, slow rxn time, cautious, underestimate own abilities
- depression