Stroke Level 4 Questions and Answers
Rated A+
Apraxia - ANSWER--the inability to carry out learned sequential movements on
command
Broca's aphasia - ANSWER--nonfluent aphasia
-damage to the frontal lobe of the brain
-frequently speak in short phrases that make sense but are produced w great effort
-often omit words like "is" "and" "the"
-understands others
-often aware of difficulties and frustrated
Cerebral blood flow regulation - 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
Common long term disabilities of stroke - ANSWER--hemiparesis
-inability to walk
-complete or partial dependance for ADLs
-aphasia
-depression
Diagnosing stroke - ANSWER--goals: confirm diagnosis of stroke and identify the cause
, -CT or MRI: distinguish between ischemic and hemorrhagic stroke, size and location of
stroke
-CTA: visualization of cerebral blood vessels, can be done after or during CT
-MRA: can detect vascular lesions and blockages
-cardiac imaging: recommended because many strokes are caused by blood clots from
the heart
-cerebral angiography: study to identify source of SAH
-risks involved: dislodging an embolus, causing vasospasm, inducing further
hemorrhage, provoking an allergic reaction to contrast media
-digital subtraction angiography (DSA): uses smaller catheters than angiography and
shorter time periods, involves the injection of a contrast agent to visualize blood vessels
in the neck, considered safer
-transcranial Doppler: detects micro-emboli and vasospasm, good for SAH
-carotid duplex scanning: used to detect cause of stroke and treat carotid stenoses
-lumbar puncture: done to look for RBCs in the cerebrospinal fluid if an SAH is
suspected but CT does not show hemorrhage
-LICOX system: measures brain O2 and temp, used to evaluate progression of a stroke
Drug therapy for Ischemic Stroke - ANSWER--Fibrinolytic therapy: recombinant tissue
plasminogen activator (tPA), used to produce localized fibrinolysis by binding to the
fibrin in the thrombi, lyses the clot
-administered via IV
-reestablishes blood flow through blocked artery
-must be administered w/I 3-4.5 hrs of the onset of ischemic stroke
-before tPA: pts screened to rule out hemorrhagic stroke, glucose levels, coagulation
disorders, hx GI bleeding, stroke, head trauma, or major surgery
-BP control critical during administration and for 24 hrs after
-Intraarterial administration also possible for up to 6 hrs after stroke symptoms
-Neurovascular specialist inserts catheter, immediately targets clot, less tPA needed
when clot directly targeted
-Aspirin 325 may be administered within 24-48hrs after the onset of ischemic stroke
-after stabilization, pts with strokes caused by thrombi and emboli may be treated with
anticoagulants and platelet inhibitors
Hemorrhagic stroke - ANSWER--result from bleeding into the brain tissue itself or into
the subarachnoid space or ventricles
-INTRACEREBRAL HEMORRHAGE:
-bleeding within the brain caused by a rupture of a vessel
-poor prognosis
-HTN is the most common cause
-other causes: vascular malformations, coagulation disorders, anticoagulant and
thrombolytic drugs, trauma, brain tumors, and ruptured aneurysms
-commonly occurs during periods of activity
-usually sudden onset with progression over mins to hrs
-common manifestations: neuro deficits, HA, n/v, decreased LOC, HTN
Rated A+
Apraxia - ANSWER--the inability to carry out learned sequential movements on
command
Broca's aphasia - ANSWER--nonfluent aphasia
-damage to the frontal lobe of the brain
-frequently speak in short phrases that make sense but are produced w great effort
-often omit words like "is" "and" "the"
-understands others
-often aware of difficulties and frustrated
Cerebral blood flow regulation - 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
Common long term disabilities of stroke - ANSWER--hemiparesis
-inability to walk
-complete or partial dependance for ADLs
-aphasia
-depression
Diagnosing stroke - ANSWER--goals: confirm diagnosis of stroke and identify the cause
, -CT or MRI: distinguish between ischemic and hemorrhagic stroke, size and location of
stroke
-CTA: visualization of cerebral blood vessels, can be done after or during CT
-MRA: can detect vascular lesions and blockages
-cardiac imaging: recommended because many strokes are caused by blood clots from
the heart
-cerebral angiography: study to identify source of SAH
-risks involved: dislodging an embolus, causing vasospasm, inducing further
hemorrhage, provoking an allergic reaction to contrast media
-digital subtraction angiography (DSA): uses smaller catheters than angiography and
shorter time periods, involves the injection of a contrast agent to visualize blood vessels
in the neck, considered safer
-transcranial Doppler: detects micro-emboli and vasospasm, good for SAH
-carotid duplex scanning: used to detect cause of stroke and treat carotid stenoses
-lumbar puncture: done to look for RBCs in the cerebrospinal fluid if an SAH is
suspected but CT does not show hemorrhage
-LICOX system: measures brain O2 and temp, used to evaluate progression of a stroke
Drug therapy for Ischemic Stroke - ANSWER--Fibrinolytic therapy: recombinant tissue
plasminogen activator (tPA), used to produce localized fibrinolysis by binding to the
fibrin in the thrombi, lyses the clot
-administered via IV
-reestablishes blood flow through blocked artery
-must be administered w/I 3-4.5 hrs of the onset of ischemic stroke
-before tPA: pts screened to rule out hemorrhagic stroke, glucose levels, coagulation
disorders, hx GI bleeding, stroke, head trauma, or major surgery
-BP control critical during administration and for 24 hrs after
-Intraarterial administration also possible for up to 6 hrs after stroke symptoms
-Neurovascular specialist inserts catheter, immediately targets clot, less tPA needed
when clot directly targeted
-Aspirin 325 may be administered within 24-48hrs after the onset of ischemic stroke
-after stabilization, pts with strokes caused by thrombi and emboli may be treated with
anticoagulants and platelet inhibitors
Hemorrhagic stroke - ANSWER--result from bleeding into the brain tissue itself or into
the subarachnoid space or ventricles
-INTRACEREBRAL HEMORRHAGE:
-bleeding within the brain caused by a rupture of a vessel
-poor prognosis
-HTN is the most common cause
-other causes: vascular malformations, coagulation disorders, anticoagulant and
thrombolytic drugs, trauma, brain tumors, and ruptured aneurysms
-commonly occurs during periods of activity
-usually sudden onset with progression over mins to hrs
-common manifestations: neuro deficits, HA, n/v, decreased LOC, HTN
