Stroke (Hon) Flashcards
List facts about stroke (cause of death, incidence, etc)
3rd leading cause of death in US
Leading cause of long-term disability in US
Annual health care cost>$40 billion
Annually, 90,000 women & 60,000 men die, 2/3 within 90 days of stroke
Among survivors, majority will have residual impairment and disability
Approximately 25% of survivors will have another stroke
Important cause of death and disability in women, including both pregnancy and postpartum period
Under age 45 yr, more women die from stroke than from myocardial infarction
What are the subtypes of stroke?
Hemorrhagic stroke (20% of cases) Intracerebral hemorrhage (cortical vs subcortical) Subarachnoid hemorrhage
Ischemic stroke (80%) Large artery atherosclerosis with thromboembolism Small vessel (lacunar) disease Cardioembolism Nonartherosclerotic vasculopathies Hypercoagulable States
What are the risk factors for stroke?
Increasing age Previous TIA or stroke atherosclerosis Cardiac disorders Drug abuse (IVDA, cocaine, amphetamines) Oral contraceptives Pregnancy/postpartum period Fibromuscular dysplasia Hypercoagulable states Inflammatory disorders Migraine
Describe atherosclerosis risk factors for stroke
HTN
Smoking
Diabetes mellitus
Hyperlipidemia
Describe cardiac disorder risk factors for stroke
Valvular heart disease (dysfunctional or prosthetic valve)
Cardiac dysrhythmia (atrial fibrillation)
Mural thrombus
Endocarditis
Atrial myxoma
Interatrial septal abnormalities
Describe hypercoaguable states risk factors for stroke
Thrombocytosis Polycythemia Sickle cell disease Leukocytosis Protein C, protein S deficiency Homocysteine Anticardiolipin/antiphospholipid antibodies
Describe inflammatory disorders risk factors for stroke
Giant cell arteritis SLE Polyarteritis nodosa Granulomatous angiitis Syphilitic arteritis AIDS
What are the symptoms of stroke in left hemisphere?
Aphasia
Right-sided sensory symptoms
Right-sided motor symptoms
Right visual field cut
What are the symptoms of stroke in right hemisphere?
Left hemineglect
Left-sided sensory symptoms
Left-sided motor symptoms
Left visual field cut
What are symptoms of stroke in cerebellar region?
Ipsilateral ataxia
Vertigo
Nystagmus
What are symptoms of stroke in brainstem?
Cranial nerve finding with contrallateral hemisensory or hemimotor symptoms
Vertigo
Describe general management of stroke
Primary prevention
Management of acute stroke itself (major area of change)
Prevention or control of medical complications (complications accoutn for 50% of deaths attributable to stroke: pneumonia, DVT, PE, UTI, decubitus ulcers)
Rehabilitation
Prevention of recurrent stroke
Describe emergent diagnosis and treatment of stroke
ABC’s: airway, breathing, and circulation
BP, pulse, cardiac monitor, EKG, O2 saturation
- acute HTN is common in acute ischemic stroke and in most cases should NOT be treated
- area of infarction may have lost autoregulatory function, so that “normal” BP may be relatively hypotensive in braine
IV access
- all stroke pts need this
- IVF’s should NOT include glucose as hyperglycemia is associated with worse neurologic outcomes
- If tPA is a consideration, 2 IV access sites will be needed to eliminate venipuncture after infusion
Neurologic examination and rapid transport to CT scan
Labs (CBC c diff, PT/PTT, full chemistry panel & fingerstick glucose, UA, CXR)
Describe NIH stroke scale
Important if tPA or intra-arterial intervention is a consideration
Score ranges from 0 (normal) to 42 (coma) and can be used to predict hemorrhagic conversion
-score20 = 17% risk of hemorrhage
Describe summary of evaluation and treatment of acute stroke
Maintain airway, breathing, circulation Elevate HOB to 30 degrees O2 @ 2 liters per NC Obtain vital signs and establish IV with NS EKG Obtain pt weight Try to identify cause and treat fever if present Obtain history
What history should you obtain for evaluation and treatment of acute stroke?
When was last time pt known to be without symptoms?
Did head trauma or seizure occur at onset of symptoms?
Is pt on warfarin/heparin?
Does pt have symptoms suggestive of MI?
Does pt have symptoms suggestive of intracranial hemorrhage?
Describe actions if CT findings show cerebral infarction or is normal
Cerebral infarction
If pt meets all tPA criteria, consider administering tPA if absolutely sure of time deficits began
Normal
Consider another cause: seizure, migraine, hypoglycemia
If history not consistent with ischemia, consider tPA or other therapies (ASA, Aggrenox, Ticlid, Plavix)
Describe IV thrombolytic therapy: tPA
Results of parts 1 and 2 of NINDS rt-PA stroke study support use of tPA for treatment of acute ischemic stroke in patients who meet eligibility requirements if treatment is initiated within 3 hours of onset of symptoms (maybe better if within 1.5 hr)
Of pts treated with tPA, 31-50% had complete or near-complete recovery at 3 months as compared with 20-38% of pts given placebo
Describe eligibility criteria for IV tPA
Age>= 18 yr
Diagnosis of ischemic stroke with clinically apparent neurological deficits
No stroke or head trauma in preceding 3 mo
No major surgery in preceding 14 days
No h/o intracranial hemorrhage
No rapidly resolving symptoms of only minor symptoms of stroke
No symptoms suggestive of SAH
No GI or GU hemorrhage in preceding 21 days
No arterial puncture at non-compressible site in preceding 7 days
No seizure at onset of symptoms
PT=100,000 mm3
Blood glucose > 50 mg/dl
SBP
Describe treatment of acute ischemic stroke with IV tPA
Infuse tPA at dose of 0.9 mg/kg (max 90 mg) over 60 min period with first 10% of dose given as bolus over 1 min period
Perform neuro assessments and check BP q15min during infusion, q30min for 6 hr after, and then q60min for next 16hr (in ICU/stroke unit)
If severe HA, acute HTN, or N/V occur, stop infusion and obtain emergent CT head
If SBP>180 or DBP>105 mm Hg, check BP more frequently and give anti-HTN drugs as needed to maintain BP at below these levels
Describe anticoagulation with heparin for stroke
Sometimes used in effort to
- prevent or limit progression in pts with acute atherothrombotic infarction
- or to prevent recurrent embolism in pts with cardioembolic stroke
But no consensus of indications, optimum level, duration, or loading bolus
AHA guidelines for acute ischemic stroke:
-strongly recommends prophylactic administration of heparin or low-molecular-weight heparin or heparinoids to prevent DVT in immobilized pts with acute stroke when there is no contraindications to antithrombotic drugs
What agents can be used for stroke?
Aspirin Aggrenox Ticlid Plavix Persantine Warfarin Low molecular wt heparin Dagibatran etxilate (Pradaxa) Riveroxaban (Xarelto) Apixaban (Eliquis)
Describe aspirin (ASA) use for stroke
Antiplatelet agent
50-325 mg seems to decrease risk of stroke by approximately 25%
Increasing doses of ASA do not seem to increase efficacy, but do increase side effects
Recent data suggests that ACE inhibitors may interact with ASA, resulting in poor HTN control
Describe aggrenox for stroke
Antiplatelet agent
ASA 25 mg / 200 mg extended-release dipyridamole
ESPS2 study: Reduced risk of stroke by 37% compared to placebo and by 22% compared to ASA 50mg/day
Common ADR: headache (39.2%)
Describe plavix for stroke
Antiplatelet agent
Similar to ASA for prevention of stroke
Caprie trial: decreased risk of stroke by 9% over ASA
TASS trial: decreased risk of stroke by 12% over ASA
NEJM article - link to TTP: 10/11 cases developed within 2 weeks after starting plavix
In what clinical situations is warfarin generally indicated?
Atrial fibrillation Prosthetic valve MI Atrial septal defect Hypercoagulable state Large vessel disease (carotid or vertebral dissection or large artery intracranial stenosis) Aortic arch disease
Describe early diagnostic testing for stroke
In addition to emergent CT scanning of brain, other studies may include CT perfusion studies, MRI, MRA, diffusion weighted and perfusion weighted MRI, transcranial doppler ultrasonography, CT angiography, xenon-enhanced CT, single-photon-emission CT, and cerebral angiography
Above tests would be selected to establish anatomical regions and structures involved and cause of infarct, thereby choosing appropriate interventions
Describe carotid angioplasty with stent placement
Early data shows lower risk of complications than CEA
Consideration when pt at high risk for surgery
-severe CAD or valvular heart disease, distal carotid disease, or bilateral severe carotid disease
Describe endovascular therapy (intra-arterial thrombolysis with clot retrieval)
Early studies showed no difference in outcome when compared to later trials, but this was likely due to poor devices
As devices have improved, now several good, solid studies showing significant improvement in pt outcomes when compared to standard therapy
