4 Etiologies of CVA/Stroke Flashcards
What are the 4 types?
Ischemic - thrombotic
Ischemic - embolic
Hemorrhage - intracerebral
Hemorrhage - subarachnoid
Key question/observation for
Hemorrhage - intracerebral
Upon straining
Key question/observation for
Hemorrhage - subarachnoid
THUNDER CLAP headache
Ischemic Thrombotic CVA/Stroke
What is atherosclerosis?
What are the types?
Complications of the late stage?
“Athero” meaning soft, fatty, glue-like
“atheroma” meaning a fomration of “athero” within vessel that results in luminal narrowing
Thick - Hard - Less Elastic
Present with low distal perfusion, may develop aneurysms, prone to rupture with hypertension
Ischemic Thrombotic CVA/Stroke
What are the vessels at risk?
Internal carotid (carotid endarterectomy)
Upper vertebral (angioplasty)
Lower basilar (Rx & prevention)
Ischemic Thrombotic CVA/Stroke
What are the risks?
8
High cholesterol, triglycerides, lipids
Hypertension
Stress increases cortisol (lipids) & catecholamines
Hereditary
Sedentary lifestyle (lack of exercise)
Birth control pill, smoking & weight gain
Cardiac disease, dysrythmia
Diabetes Mellitus
Ischemic Thrombotic CVA/Stroke
What’s the prevention?
EMS care/Acute management?
Antiplatelet agents to prevent atherothrombosis
ASA & ticlopine are used most often
Carotid endarterectomy for internal carotid TIA
Angioplasty
Position the patient on their affected (body) side with the head elevated @ 30 degrees
High concentration oxygen & assisted ventilation with support of spontaneous breathing & augmentation of rate to no greater than 20 min.
Ischemic Embolic CVA/Stroke
What are the causes/risks for HYPERTENSION & ATHERTHROMBOTIC PLAQUE?
What are the causes/risks for IMPAIRED BLOOD FLOW LEADING TO STASIS?
What are the causes/risks for DAMAGED VALVE LEADING TO CLOT/FIBRIN EMBOLI?
It is an Embolus from atheromatous plaque in the carotid sinus or internal carotid artery.
Diabetes, hyperlipidemia, smoking, b/c pill, prior, overweight or + weight gain, sedentary lifestyle
CSM or Chiropractic neck manipulation.
Hyper viscosity syndromes & Glue sniffing
Recent AMI with dyskinetic left ventrical
Atrial Fibrillation
Rheumatic Heart disease
Prosthetic valves
Bacterial Endocarditis
Mitral Valve Prolapse
Ischemic Embolic CVA/Stroke
What area of the brain is USUALLY affected (the vessel)?
The # of emboli determines?
The left middle cerebral artery, especially the upper division, is the most frequent site of cerebral emboli b/c it is straighter which means less resistance to emboli
the extent of damage
Ischemic Embolic CVA/Stroke
What’s the prevention?
What’s the EMS care/Acute management for an ischemic embolic stroke?
Decrease other risk factors which cause hypertension & atherothrombotic plaque.
Avoid CSM & neck manipulation
Antiplatelet agents – warfarin more effective than ASA for preventing ischemic stroke
associated with AF
Thrombolytic therapy for acute care
Position the patient on their affected (body) side with the head elevated @ 30 degrees
High concentration oxygen & assisted ventilation with support of spontaneous breathing & augmentation of rate to no greater than 20 min
Intracerebral hemorrhage (ICH) CVA/Stroke
What does it mean?
How does it happen?
intraparenchymal means deep tissue (there’s a hematoma deep in the brain tissue)
- Bleeding occurs in the space surrounding the tissue.
- Distal brain cells become hypoxic immediately resulting in a focal presentation. (e.g., weakness in one hand).
- Blood is particularly irritating to local arteries which spasm in response to contact.
- The spasm may involve quite a large area resulting in an ever expanding / evolving presentation.
- Clot will form & brain tissue in the area becomes liquid.
- Clot eventually is removed by phagocytosis & replaced with blood vessels, astroglia fibers & fibrin to fill void.
*Brain tissue does not replace dead cells.
Intracerebral hemorrhage (ICH) CVA/Stroke
What’s the symptom onset?
What are the complications?
What are the causes?
Slower to get worse
Initially focal
necrotic tissue & the edema causes herniation through the tentorium.
missile injury
tumors which bleed
hypertensive crisis (50% of cases)
arteriosclerosis
Intracerebral hemorrhage (ICH) CVA/Stroke
Where is it usually located?
Who does it affect?
anterior portion of the temporal lobes & the posterior portion of the frontal lobes
older men (68)
Intracerebral hemorrhage (ICH) CVA/Stroke
What’s the prevention?
What’s the EMS care/Acute management?
Stop the use of alcohol, tobacco, & use of cocaine & amphetamines
Mannitol & other osmotic agents reduce ICP caused by edema
Position the patient on their affected (body) side with the head elevated @ 30 degrees
High concentration oxygen & assisted ventilation with support of spontaneous breathing & augmentation of rate to no greater than 20 min
Intracerebral hemorrhage (ICH) CVA/Stroke
What’s the prognosis for a supratentorial hematoma GREATER than 5cm?
What about an infratentorial (pontine) hematoma GREATER than 3cm?
Poor
FATAL!!
Subarachnoid hemorrhage (SAH) CVA/Stroke
What’s the cause?
Who’s the target demographic?
What is the usual location, size, and apearance?
A rupture of blood vessels which merge with the sub-arachnoid space (the saccular aneurysms – circle of willis)
AND/OR
A laceration of arachnoid vessels caused by missiles or blunt trauma to brain (contusions).
45% younger than 55 y/o
Can affect children
the elderly & alcoholics
located at bifurcations
Small - pinpoint 2-3cm in diameter
Think walled blisters that gradually enlarge
Subarachnoid hemorrhage (SAH) CVA/Stroke
What’s the symptom onset?
How long can it last?
What are the symptoms of meningeal irritation?
abrupt with the “worst headache” or “something snapped” CC
nuchal rigidity
sensorium deterioration
coma
convulsions
min-hours-days
Nuchal rigidity
Severe acute onset & intense headache
Photophobia
Projectile vomiting
Trauma may or may not be evident
Subarachnoid hemorrhage (SAH) CVA/Stroke
What are the causes?
What are the complications?
Provoked by hypertension
Exacerbated by anticoagulation therapy or bleeding disorders
Occurs during periods of:
- stress
- exertion
- valsalva maneuvers
- coitus
- labour & delivery
- weight lifting - WITH or without the use of anaboic steroids
Subarachnoid hemorrhage (SAH) CVA/Stroke
What are the complications?
What’s the prevention?
hemorrhage extending into the ventricle system
temporal lobe herniation
midbrain compression
Major therapeutic emphasis is on preventing predictable complications of re-rupture
Subarachnoid hemorrhage (SAH) CVA/Stroke
What’s the EMS care/Acute management plan?
Re-bleeding management is central to the management of ruptured aneurysms.
Quiet dark room, given stool softener, analgesia
Position the patient on their affected (body) side with head elevated @ 30 degrees
High concentration oxygen & assisted ventilation with support of spontaneous breathing & augmentation of rate to no greater than 20 min.
How many cc’s of blood can the brain tolerate WITHOUT clinical manifestations (symptoms)?
What’s considered lethal in the brainstem?
100cc
5ml clot
