Stroke - Level 4
Stroke - ✔✔ correct answer -occurs when there is ischemia to part of the brain or hemorrhage into
the brain that results in death of brain cells
-functions controlled by that portion of the brain are impaired or lost
-also called brain attack and cerebrovascular accident (CVA)
-can occur at any age
Common long term disabilities of stroke - ✔✔ correct answer -hemiparesis
-inability to walk
-complete or partial dependance for ADLs
-aphasia
-depression
Cerebral blood flow regulation - ✔✔ correct answer -blood flow must be maintained at 750 to 1000
mL/min or 20% of cardiac output for optimal brain functioning
-if blood flow is totally interrupted neuro metabolism is altered in 30 secs
-metabolism stops in 2 mins
-cellular death occurs in 5 mins
-cerebral auto regulation: changes in the diameter of cerebral blood vessels in response to changes
in pressure so that blood flow to the brain stays constant
-when ischemia occurs, impairs auto regulation
-CO2 = potent vasodilator
-increased CO2 levels increase cerebral blood flow
-decreased CO2 levels decrease cerebral blood flow
-arterial O2 less than 50 mm Hg increases cerebral blood flow
-increased H+ concentration increases cerebral blood flow
-factors affecting blood flow to the brain: systemic BP, cardiac output, and blood viscosity
-if cardiac output is reduced by 1/3rd cerebral outflow will be reduced
-decreased viscosity increases flow
-collateral circulation: develops to compensate for a decrease in cerebral blood flow, the vessels in
the brain make an alternate route
-if one vessel is blocked, blood will flow from the intact artery to the damaged one preventing CVA
-increased ICP causes compression and reduced cerebral blood flow
, Stroke - Level 4
Risk factors for CVA - ✔✔ correct answer NONMODIFIABLE
-male gender
-advanced age (>65)
-African Americans
-family hx of stroke
-sickle cell disease
-migraine headaches
MODIFIABLE
-HTN***
-heart disease: a fib**, MI, cardiomyopathy, valvular abnormalities
-diabetes mellitus
-smoking
-excessive alcohol consumption
-obesity (especially abdominal)
-sleep apnea
-metabolic syndrome
-lack of physical exercise
-poor diet: high fat and low in fruits and veg
-drug abuse
-increased cholesterol
-early forms of birth control pills with high levels of progestin and estrogen
Transient Ischemic attack (TIA) - ✔✔ correct answer -a transient episode of neuro dysfunction
caused by focal brain, spinal cord, or retinal ischemia
-there is no acute infarction of the brain
-symptoms last less than an hour
-likely caused by micro emboli that temporarily block the blood flow
-pts should seek treatment immediately, no way to predict if it will turn into a stroke
-warning sign of progressive cardiovascular disease
-1/3 of pts will not have another event
Stroke - ✔✔ correct answer -occurs when there is ischemia to part of the brain or hemorrhage into
the brain that results in death of brain cells
-functions controlled by that portion of the brain are impaired or lost
-also called brain attack and cerebrovascular accident (CVA)
-can occur at any age
Common long term disabilities of stroke - ✔✔ correct answer -hemiparesis
-inability to walk
-complete or partial dependance for ADLs
-aphasia
-depression
Cerebral blood flow regulation - ✔✔ correct answer -blood flow must be maintained at 750 to 1000
mL/min or 20% of cardiac output for optimal brain functioning
-if blood flow is totally interrupted neuro metabolism is altered in 30 secs
-metabolism stops in 2 mins
-cellular death occurs in 5 mins
-cerebral auto regulation: changes in the diameter of cerebral blood vessels in response to changes
in pressure so that blood flow to the brain stays constant
-when ischemia occurs, impairs auto regulation
-CO2 = potent vasodilator
-increased CO2 levels increase cerebral blood flow
-decreased CO2 levels decrease cerebral blood flow
-arterial O2 less than 50 mm Hg increases cerebral blood flow
-increased H+ concentration increases cerebral blood flow
-factors affecting blood flow to the brain: systemic BP, cardiac output, and blood viscosity
-if cardiac output is reduced by 1/3rd cerebral outflow will be reduced
-decreased viscosity increases flow
-collateral circulation: develops to compensate for a decrease in cerebral blood flow, the vessels in
the brain make an alternate route
-if one vessel is blocked, blood will flow from the intact artery to the damaged one preventing CVA
-increased ICP causes compression and reduced cerebral blood flow
, Stroke - Level 4
Risk factors for CVA - ✔✔ correct answer NONMODIFIABLE
-male gender
-advanced age (>65)
-African Americans
-family hx of stroke
-sickle cell disease
-migraine headaches
MODIFIABLE
-HTN***
-heart disease: a fib**, MI, cardiomyopathy, valvular abnormalities
-diabetes mellitus
-smoking
-excessive alcohol consumption
-obesity (especially abdominal)
-sleep apnea
-metabolic syndrome
-lack of physical exercise
-poor diet: high fat and low in fruits and veg
-drug abuse
-increased cholesterol
-early forms of birth control pills with high levels of progestin and estrogen
Transient Ischemic attack (TIA) - ✔✔ correct answer -a transient episode of neuro dysfunction
caused by focal brain, spinal cord, or retinal ischemia
-there is no acute infarction of the brain
-symptoms last less than an hour
-likely caused by micro emboli that temporarily block the blood flow
-pts should seek treatment immediately, no way to predict if it will turn into a stroke
-warning sign of progressive cardiovascular disease
-1/3 of pts will not have another event
