Stroke Flashcards
A stroke is also known as a ____.
Cerebral Vascular Accident (CVA)
What is a stroke? What are the two types of stroke?
Sudden loss of neurological function as the result of a disruption to blood flow resulting in tissue death.
Types:
- Ischemic
- Hemorrhagic
Stroke is the ___th leading cause of death in the US
5th
Leading cause of serious long term disability
What are the top 3 CONTROLLABLE risk factors for stroke? List the other 5 controllable risk factors.
- Hypertension (BP > 160/95 mmHg)
- Smoking (increases risk by 50%)
- Hyperlipidemia
Cardiac disease Diabetes Obesity Sedentary lifestyle Excessive alcohol consumption (>3-4 drinks/day increases risk by 40%)
What are 5 risk factors for stroke that we CANNOT control?
- Age (incidence increases with age)
- Sex (Females 20% < men, levels out with age)
- Heredity (risk greater with family history)
- Race (African Americans > Hispanics > Caucasians)
- Geography (Southeast US highest death rate)
What are 5 warning sign of stroke?
- Sudden numbness/weakness of face/arm/leg
- Sudden difficulty speaking or understanding speech; increased confusion
- Sudden trouble seeing in one or both eyes
- Sudden trouble walking, dizziness, loss of balance or coordination
- Sudden severe headache with no known cause
What is the relationship between time and stroke related disability?
Those who arrive to the ED within 3 hrs. of the start of symptoms tend to have less disability 3 months post CVA
What does the acronym FAST stand for?
Facial droop
Arm weakness
Speech difficulties
Time (tongue deviation)
What are 9 diagnostic tests that can be done to detect stroke?
- Non contract CAT scan (common): differentiates ischemic from hemorrhagic
- MRI: assess size/extent of infarct
- MRA: assess atrial stenosis/presence of aneurysm
- EKG: detects Afib
- Echo: assess heart ventricular/valve function
- Echo with bubble: r/o patent foramen ovalus (PFO)
- Telemetry: min 24 hours
- Carotid Doppler: detects stenosis due to plaque accumulation
- TEE (trans esophageal echocardiogram): determines origin/source of infarct
What is tPA? When should it be used (timeframe)? Why is it important?
tPA- tissue plasminogen activator
Results in lysis of fibrin
Used with ischemic stroke to prevent disability post event
Use with 3 hours of the stroke for optimal results
What is the University of Oxford ABCD Scale?
Performed in MD office
***Predictor of stroke after TIA
Scale:
- Age—1 point over 60
- Blood Pressure—1 point for systolic above 140 mmHg or diastolic above 90 mmHg
- Clinical features—- 2 points for one sided weakness and 1 point for speech issues w/o weakness
- Duration—2 points for symptoms > 60 min and 1 point < 60 min
Score w/in 7 days: 0-4=4% chance,5=12% chance, 6=32% chance
What is the NIH stroke scale?
Standardized tool to assess if impairments warrants use of tPA
Performed at:
- Baseline
- 2 hrs. post treatment
- 24hrs from symptom onset
- 7-10 days later
- 3 months
Max score of 42 (severe stroke)
score of 12-20 = best outcomes
___ % of all CVAs are ischemic.
80%
What is an ischemic stroke?
Decreased blood flow resulting in tissue death
What are 2 types of ischemic stroke?
- Thrombotic: aggregation of platelets & fibrin in a cerebral artery resulting in occlusion
gradual onset
often awaken with symptoms - Embolic: thrombus that originates elsewhere breaks away and is carried through bloodstream to a narrowing region
abrupt onset; often with activity
most common area of origin is cardiac—post surgery
What is a lacunar infarct?
Occlusion of small vessels; may be gradual onset
Associated with hypertension or diabetes
Tissue death is evident
What is a transient ischemic attack?
Short period of disrupted blood flow with complete recovery of symptoms
Symptoms recover within 24 hours
15% of CVA’s had a reported TIA
What occurs in an ischemic cascade?
Refer to slide 22 of the stroke PPT
Too much info and I’m not about to type it all out
What is an ischemic penumbra?
Rim of mild to moderately ischemic tissue around the area of infarction is evolving
Remains viable for several hours due to collateral arteries
Tissue death if reperfusion is not established during the early hours
Brain tissue requires ____ % of regular blood flow to survive.
20-25%
What are 5 common medications prescribed post stroke?
- Antiplatelets (prevents clot formation)
- Anticoagulants (increase clotting time)
- Statins (blocks enzymes that produce LDL cholesterol)
- Antihypertensive (beta blockers/ACE inhibitors)
- Diabetic Medications
What are the symptoms associated with a hemorrhagic stroke?
Sudden onset
Closely linked to HTN
Decreased level of consciousness, headache, nausea and vomiting
What are 4 types of hemorrhagic strokes?
- Intracerebral hemorrhage
- Subarachnoid hemorrhage
- Subdural hematoma
- Epidural hematoma
What is an intracerebral hemorrhage? What percentage of strokes are they responsible for?
Arterial bleeding into the brain parenchyma (intraparenchymal hemorrhage)
Responsible for 15% of all strokes
High mortality rate from stroke is dependent on what 4 factors?
- size
- degree of neuro deficits
- location (midline = mortality)
- rapid development
What is the underlying etiology of primary intracerebral hemorrhage (ICH)?
- Atherosclerosis weakens small arterial walls
- Sudden increase in BP
- Over 65 yo doubles w/ each decade
What are the 3 clinical manifestations of ICH?
- specific to region
- sx increase as hematoma enlarges
- seizure activity possible (esp. in cerebral cortex)
What 3 things occur as a result of an ICH?
- Distortion of structures
- Rise in intracranial pressure
- Development of severe edema causing midline shift