Strokes

Causes of a blockage in ischemic strokes

A blood clot either a thrombus or in emboli, or from stenosis of a vessel caused by a buildup of plaque

When maximum neurological deficit from a stroke in evolution has been reached usually by three days the condition is called

A completed a stroke

Client may also experience amaurosis fugax with a TIA

A fleeting blindness of one I described as a shading coming down over vision with the affected eye

Transient ischemic strokes

A mini stroke, is a brief period of localized cerebral ischemia that causes neurological deficit's lasting for less than 24 hours

Contralateral deficit

A stroke in the right hemisphere of the brain is manifested by deficits in the left side of the body and vice versa

Antiplatelet agents often used to treat clients with TIAs or those who had a previous stroke such as

Aspirin, clopidogrel, dipyridamole, ticlopidine

Ischemic thrombotic stroke

Caused by occlusion of a large cerebral vessel by a thrombus

If BP levels greater than 185/110 then

Client cannot be treated with IV TPA

Deficits that occur with TIA

Contralateral numbness or weakness of the leg hand and forearm and corner of the mouth, aphasia visual disturbances

TPA or tissue plasminogen activator

Converts Plasminogen to Plasmin resulting in fibrinolysis of the clot

These drugs have been used to treat cerebral edema but the results are not always positive

Corticosteroids such as prednisones or dexamethasone

In a lumbar puncture test Frank blood may be seen in the CSF if the patient had this type of stroke

Hemorrhagic stroke

Most common cause of a hemorrhagic stroke

Hypertension

Monitor clients body temperature as this may develop

Hyperthermia

Lacunar strokes which are thrombotic stroke affecting the smaller cerebral vessels

Leaves a small cavity or lake in the brain tissue

Hemianopia

Loss of half of the visual field of one or both eyes

If client has increased intracranial pressure hyper all smaller solutions such as these may be administered

Mannitol or diuretics

Sensory perception all deficits in patients who had a stroke

May include deficits in vision, hearing, equilibrium, taste and sense of smell also the ability to perceive vibration pain warmth called and pressure may be impaired

A thrombus

May remain in place and continue to enlarge occluding the lumen of the vessel or it may break off and become an embolus

Warfin sodium

Maybe given orally

Sodium heparin

Maybe given subcutaneously or by continuous IV drip

Lumbar puncture

Maybe performed to obtain CSF if there is no danger of increased intracranial pressure

Hemorrhagic stroke can also occur due to this

Aneurysm that ruptured is releasing blood into the brain

Do not dissolve and existing clot, they prevent further extension of the clot and formation of new clots

Anticoagulants

These are never administered to a client with a hemorrhagic stroke

Anticoagulants

Autoregulation

Allows the brain to maintain a constant blood flow despite changes in systemic blood pressure

Flaccidity

Absence of muscle tone hypotonia

Hemorrhagic stroke most often occurs in these individuals

Assisting increased in systolic and diastolic blood pressure

Most frequent sites of cerebral emboli

At bifurcations of vessels, particularly those of the carotid and middle cerebral artery's

Not effective when systemic blood pressure falls below 50 MMHG or rises above 160 MMHG

Autoregulation

Carotid angioplasty

Balloon catheter inserted through an artery in the clients arm or leg and advanced to the area of the carotid artery he stenosis, a small filter is inserted to catch any clots or pieces of debris that might break loose. Balloon is inflated to widen the artery and a permanent stent is inserted

If increased intracranial pressure causes seizures anticonvulsants may be prescribed such as these

Barbiturates and phenytoin(dilantin)

Reason that strokes lead to loss of sensormotor functions on the side of the body opposite the side of the brain that is damaged

Because the motor pathways cross at the junction of the medulla and spinal cord

Subarachnoid hemorrhage results from

Bleeding into the spaces around the brain

Intracerebral hemorrhage results from

Bleeding within the brain

Proprioception

Body's senses of its position in space this is lost sometimes in a patient has a stroke

Cerebral infarction's visible within 6 to 8 hours post stroke can be seen on this

CT scan

Diagnostic test useful in distinguishing the type of stroke

CT scan

Hemorrhage strokes visible immediately on this

CT scan

Survival of penumbra

Depends on a timely return of adequate circulation

If embolus breaks up into smaller fragments and is absorbed by the body the manifestations will

Disappear in a few hours to a few days

When a completed stroke occurs the brain tissue is

Edamatous and necrotic

Given concurrently with an anticoagulant used to treat thrombotic stroke

Fibrinolytic therapy or TPA

CT scan

First imaging technique used to demonstrate the presence of hemorrhage, tumors, aneurysm, ischemia, Adema and tissue necrosis

To be effective TPA should be given

IV within three hours of the onset of manifestations after CT scan to confirm the occurrence of an ischemic stroke

Apraxia

Inability to carry out some motor pattern

Agnosia

Inability to recognize one or more subjects that were previously familiar

Alterations in mental status and level of consciousness in movement indicate this

Increased intracranial pressure which is the major cause of death in the acute phase of a stroke

Spasticity

Increased muscle tone or hypertonia

Etiology of TIA

Inflammatory artery disorders, sickle cell disease, atherosclerotic changes in cerebral blood glasses, thrombosis, emboli

Anti-thrombotic drugs such as aspirin and dipyridamole

Inhibits platelet face of clot formation so used as a preventative measure for clients at risk for embolic and thrombotic stroke

Most common location of thrombi

Internal carotid artery he, vertebral arteries, and the junction of the vertebral and basilar arteries

Two types of hemorrhagic stroke's

Intracerebral hemorrhage and subarachnoid hemorrhage

TPA will also increase the risk of

Intracranial hemorrhage

Penumbra

Is central core of dead or dying sells surrounded by a band of minimally perfused swells

Risk of strokes

Occur more frequently in man and risk of stroke is greater in women during pregnancy and for six weeks following birth

Manifestations of a hemorrhagic stroke

Occur suddenly and when the affected individual is engaged in some activity

Thrombotic stroke

Occurs rapidly but progresses slowly

Embolic ischemic stroke

Occurs when a blood clot or clump of matter traveling through the cerebral blood vessels become lodged in a vessel that is too narrow to permit further movement

Hemorrhagic stroke

Occurs when a blood vessel breaks open spilling blood into spaces surrounding neurons

Hemorrhagic stroke or intracranial hemorrhage

Occurs when a cerebral blood vessel ruptures

Ischemic strokes

Occurs when the blood supply to a part of the brain is interrupted by a thrombus which is a blood clot or an embolus which is foreign matter traveling through the circulation or stenosis which is narrowing

Thrombotic stroke's most often occur in this population

Older individuals who are resting or sleeping because blood pressure is lower during sleep

Hemiplegia

Paralysis of the left or right half of the body

Surgery such as carotid endarterectomy

Performed at the carotid artery by furcation to remove atherosclerotic plaque

Extracranial-intracranial bypass of the internal carotid, middle cerebral or vertebral arteries

Performed when included or stenotic vessel is not directly accessible. The process reestablish his blood flow to the affected area of the brain

Ischemic strokes

Result from blockage or stenosis of a cerebral artery decreasing blood flow and causing brain infarction

Other factors that cause a hemorrhagic stroke

Rupture of plaque encrusted artery wall, ruptured aneurysm, trauma, erosion of blood vessels by tumors, arteriovenous malformations, anticoagulant therapy and blood disorders

PLAC test

Scans the blood for high levels of lipoprotein associated with phospholipase A2

Stroke may cause partial loss of the

Sensations that trigger bladder illuminations resulting in urinary frequency, urgency or incontinence

One of the main symptoms patients suffer from a hemorrhagic stroke

Severe headache

Characteristics of an EKG and individuals with a stroke

Shortened PR interval, Pete T waves and a D pressed ST segment

Risk factors for stroke

Sleep apnea because it increases blood pressure smoking sickle cell disease and substance abuse

A woman's symptoms when having a stroke

Sudden face and limb pain, sudden nausea and sudden hick ups and sudden shortness of breath, palpitations and generalized weakness

Manifestations of an embolic stroke

Sudden onset and causes immediate deficits

Manifestations of TIA

Sudden onset and often disappear within minutes or hours

When cellular metabolism ceases cells will

Swell as sodium draws water into the cell

Clients may be deemed medically inappropriate for treatment with TPA if

Symptoms are greater than three hours

Thrombotic stroke begins with

TIAA and continues to worsen over 1 to 2 days this condition is called a stroke in evolution

Neglect syndrome

The individual cannot integrate and use perceptions from the affected side of the body and therefore ignores that side

Embolic strokes originate from this

The thrombus in the left chambers of the heart formed during atrial fib relation

Even if embolus is absorbed

The vessel wall where the embolus lodges maybe weekend increasing the potential for cerebral hemorrhage

In a lumbar puncture test the CSF pressure maybe elevated if patient had this type of stroke

Thrombotic stroke

Warning signs of an ischemic thrombotic stroke

Tia

A platelet aggregation inhibitor that reduces thrombotic stroke risk

Ticlopidine

Large vessel disease caused by plaque

Usually a result of thrombi

Manifestation of hemorrhagic stroke depend on the location but include

Vomiting headache seizures, hemiplegia and loss of consciousness

Most commonly use anticoagulant drugs therapy for ischemic stroke

Warfarin sodium, heparin and enoxaparin

Hemiparesis

Weakness of the left or right half of the body

Hypertension

When increased systemic pressure causes an increase in cerebral blood flow which results in over distention of cerebral vessels

Cellular metabolism

Will cease when blood flow to cerebral neurons is interrupted and glucose glycogen and ATP are depleted and sodium potassium pump fails

Typical clients of an embolic ischemic stroke

Younger clients and it occurs when the client is awake and active

Small vessel disease caused by plaque also called lacunar infarct's

very small infarcts in the deep non-cortical areas of the brain or brain stem