Acute Stroke
nursing management?
- ABC's - activity should increase (PT, OT) - nutrition - evaluate swallowing, assess cognitive ability to feed self, appropriate position, monitor throat clearing and coughing - elimination problems - fluids, stool softeners, short term catheters
Cerebral angioplasty?
- can reverse neurologic defects from atherosclerotic lesions - microballon catheter mechanically dilates vessels introduced via femoral artery, directed to major arteries at base of brain - risks: intracerebral hemorrhage
What does diminished blood flow and cell formation result in?
- cells lack O2 to generate energy - cellular Na-K pumps fail (b/c of O2 deficiency) - intracellular Na, Cl and Ca increase - electrolyte accumulation is toxic to intracellumar structures - severe/prolonged ischemia causes cellular death
manifestations of stroke?
- depends on area: numbness and weakness of face and arm, difficulty with balance/speech, loss of vision in one eye, contralateral hemiparesis (indicates hemispheric stroke)
Aspirin
- puts with acute IS/TIA - start within 48hrs (50-325 mg/day) - reduces stroke morality, lowers morbidity - CI: allergy, GI bleeding, tPA
Carotid endartecrectomy?
- removes source of occlusion to increase cerebral blood flow to ischemic area, mgmt of ischemic cerebrovascular disease - prevents recurring cerebral infarcts, TIAs
Diagnostics?
-trans esophageal echocardiography (TEE) - detects cariac and aortic causes of embolism - 12 lead ECG (monitor for Afib) - CBC - CT - determine type, extent, and location of injury - LP - blood in CSF = hemorrhage - serum electrolytes, blood glucose - ABGs, drug screen, serum alcohol level - dopper ultrasound - screen for presence/degree of carotid stenosis - duplex imaging - type of u/s to look at carotid
modifiable risk factors
HTN, cardiac disease, diabetes, drugs, smoking, low activity, hypercholesterdemia, dysrhythmias, coagulopathies
Non modifiable risk factors
age, gender, race, gender factors, prior stroke or MI
Hemorrhagic stroke? types?
appears suddenly; bleeding in brain tissue; intracerebral or subarachnoid
Global ischemia?
associated with lack of collateral blood flow and irreversible brain damage within minutes
Vertebrobasilar ischemia signs and symptoms?
ataxia, diplopia, hemianopsia, vertigo, cranial nerve deficits, contralateral hemiplegia, sensory deficits
hemineglect
aware of items to one side of space
Embolic stroke?
blood clot travels from original site and becomes lodged in artery that feeds brain; usually occur suddenly when person is awake and active; immediate deficits; most emboli originate from thrombus in heart that develops with certain cardiac conditions
Thrombotic stroke?
caused by blood clot that obstructs arterial blood flow; occurs rapidly; during sleep or wake (not associated with activity); preceded by TIA; evidence of plague in coronary or peripheral vasculature
Ischemic strokes? types?
caused by interruption of cerebral blood flow by a thrombi or embolus; caused by atherosclerosis - plague deposits in intimal lining of arteries cause them to weaken, platelets adhere and aggregate to tissue defect to "plug" hole --> initiates coagulation cascade, results in formation of stable fibrin clot, can occlude vessel - thrombotic and embolic
Intracerebral hemorrhage? causes? symptoms?
cerebral blood vessels rupture and blood accumulates in brain tissue; usually basal ganglia, cerebellum, brainstem or cortex, appear suddenly, no warning; causes: HTN, arteriovenous malformation, anticoagulants, aneurysms, trauma and tumors; symptoms: severe headache, nausea/vomiting, photophobia, unilateral weakness
Tetra, hemi, para?
complete or partial paralysis of upper extremities and complete paralysis of lower body parts; paralysis of one half of the body; paralysis of lower part of body, usually below waist
hemianopsia
decreased or loss of vision in one half of vision field
thrombolytic therapy?
intravenous tissue plasminogen activator (tPA) for acute ischemic stroke; goal: save damaged brain tissue and minimize permanent deficits (time to needle within 3hr window); small dose given as bolus followed by IV infusion of drug over an hour; monitor neurological and BP, O2 above 92%
majority of strokes result from?
ischemic infarction and inadequate blood flow - athersclerosis (plaque formation and narrowing/occluding of arteries), causes significant stenosis of cerebral arteries
Ataxia
loss of full control of bodily mvmts
Carotid ischemia signs and symptoms?
monocular vision loss, aphasia, hemineglect, contralateral sensory or motor loss
What is acute stroke? classifications?
neurologic deficit due to impaired blood flow to localized area of brain; results in brain tissue injury; ischemic and hemorrhagic
Central zone?
neutrons are infarcted (dead) with permanent loss of function
Goal of med mgmt?
restore cerebral blood flow and limit extension of infarcted zone
Circle of Willis
right and left internal carotid arteries and the right and left vertebral arteries branches unite to form circle of willis; connecting junction that provides collateral blood flow to either side of the brain; 80% of blood to brain
Subarachnoid hemorrhage? symptoms?
rupture of an aneurysm (weakening and dilatation of vessel wall associated w long term arthersclerosis and HTN) or due to trauma; develops suddenly; symptoms: severe headache, neck pain/stiffness (nuchal rigidity), vomiting, CSF is bloody, reduced blood flow, high ICP
Focal ischemia?
some degree of collateral circulation remains, allowing neutrons to survive and reversal of neuronal damage; treatable
Penumba?
surrounds central zone; neutrons are minimally perfused; functioning and viable but somewhat impaired function/injured; responsive to therapy within certain time (reperfusion therapy ideally within 1st hr of injury but can be 4.5hrs)
Lacunar infarcts?
thrombtic strokes involving smaller vessels; leave behind small cavities; occur in deep penetrating arteries in single region of brain
TIA? symptoms?
transient ischemic attack - brief episodes of focal neurologic deficits; usually resolve in few min-hr; do not cause permanent brain injury; precedes thrombotic strokes (warns of impeding stroke); symptoms: dim/impaired vision, weakness, numbness, tingling, headache, speechlessness, dizziness