Neuroanatomy and Symptoms of Stroke: A Comprehensive Guide, Exams of Nursing

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SCRN EXAM REVIEW EXAM 2023 /202 4

Posterior Cerebral Artery (PCA) - ANSWER Arises from basilar. Supplies Occipital Lobe , Midbrain, Thalamus, Pineal Gland, Choroid Plexus, and Corpus Callosum Symptoms of PCA Stroke - ANSWER - Contralateral Visual Field Homonymous hemianopia

• Visual Agnosia (unable to interpret/recognize visual information)
• Weber's Syndrome (3rd nerve palsy + contralateral hemiplegia)
• Parinaud's Syndrome (Impaired upwards gaze, convergence-retraction nystagmus, primary conjugate downward gaze) Anterior Inferior Cerebellar Artery (AICA) - ANSWER Feeds anterior inferior parts of the cerebellum Symptoms of AICA Stroke - ANSWER Lateral Pontine Syndrome: vertigo, vomiting, nystagmus, falling towards the side of the lesion, ipsilateral loss of sensation to the face, ipsilateral facial paralysis, ipsilateral hearing loss Posterior Inferior Cerebellar Artery (PICA) - ANSWER Feeds cerebellum, superior section of the medulla,. Choroid plexus and fourth ventricle Symptoms of PICA Stroke - ANSWER Wallenburg Syndrome (lateral Medullary Syndrome): Loss of pain and temperature sensation in the contralateral trunk and ipsilateral face Basilar Artery - ANSWER An artery, formed by the fusion of the vertebral arteries, that supplies blood to the brainstem (medulla and pons) and to the posterior cerebral arteries. Symptoms of Basilar Artery Stoke - ANSWER Coma, quadriparesis, ataxia, dysarthria, CN dysfunction and visual deficits,

Locked in Syndrome, Intranuclear Opthalmoplegia, gaze paresis, Millard Gulber Syndrome CN VI VII damage (diplopia facial weakness, loss of corneal reflex), Nausea, vomiting, diplopia, gaze palsy, dysarthria,. vertigo, tinnitus, hemiparesis, and quadriplegia. Anterior Cerebral Artery (ACA) - ANSWER Feeds the media portion of the frontal and parietal lobes as well as the corpus callosum Symptoms of ACA Stroke - ANSWER Contralateral motor/sensory deficits impacting legs > arms Middle Cerebral Artery (MCA) - ANSWER Feeds majority of the frontal, parietal, and temporal lobes, basal ganglia, internal capsule. It is divided M1 - M Symptoms of MCA Stroke - ANSWER - Aphasia if dominant hemisphere

• Neglect if non-dominant hemisphere
• Contralateral motor/sensory loss of face/arm/leg with Arms > Legs
• Anosognosia: neglect or lack of self awareness Venous Vascular Anatomy - ANSWER Venous channels enter into venous sinuses located in the Dura matter. Superior Sagittal Sinus - ANSWER Travels posteriorly between the cerebral hemispheres towards the occiput Straight Sinus - ANSWER Travels along the tentorium, draining blood from the superior cerebellar veins. Transverse Sinus - ANSWER Travels along the base of the occiput laterally and forwardly Sigmoid Sinus - ANSWER Begins beneath the temporal bone and travels to the jugular foramen where it becomes the internal jugular veins

Stroke Pathophysiology - ANSWER Arterial blood flow to the brain tissue fails to meet metabolic demands resulting in cell damage or death. ISCHEMIA FIRST THEN INFARCT. Penumbra - ANSWER Zone surrounding the core infarct, damaged by ischemia but not yet infarcted ---- functionally silent yet metabolically active Hypoxia leading to Necrotic Pathway - ANSWER Cell energy failure Hypoxia leading to Apoptotic Pathway - ANSWER Programmed cell death in the penumbral zone ICH Stroke Pathophysiology - ANSWER Occurs when a cerebral blood vessel opens abnormally and spills blood into brain tissue. Classification of ICH Brain Injury - ANSWER Primary Brain Injury: Direct result of the hematoma Secondary Brain Injury: Hours or days after ICH, mass effect causes mechanical disruption and damage to cell membranes SAH Stroke Pathophysiology - ANSWER Aneurysm from s in the cerebral vasculature and ruptures, resulting in blood spilling in the subarachnoid space Saccular Aneurysm - ANSWER narrow neck, widened dome -- Most Common Fusiform Aneurysm - ANSWER Outpouching of the vessel without a distinct neck --- Less common Early Brain Injury - ANSWER Hours and first several days after aneurysm rupture cerebral edema forms, injury results from decreased cerebral blood flow Cerebral Vasospasm (Delayed Cerebral Injury) - ANSWER Large Vessel Spasm generally begins on day 4 continues up to 21 days

Brain Requirements - ANSWER 20% of the body's Oxygen 15% of the body's Cardiac Output Cerebral Blood Flow - ANSWER Normal: 50 - 55 mL/100g/min Oligemia: 30 - 40 mL/100g/min Moderate Ischemia (the penumbra): 20 - 30 mL/100 g/min Severe ischemia and Cell Death: 0 - 10 mL/100 g/min Large Vessel occlusion - ANSWER Embolic: develop elsewhere and travel to blood vessel in the brain Small Vessel Occlusion - ANSWER Thrombotic: caused by a clot that develops in the vessel of the brain Cerebral Cortex - ANSWER Grey matter on the outermost section of the cerebrum and cerebellum Divided into four lobes

• Frontal
• Parietal
• Occipital
• Temporal Frontal Lobe - ANSWER motor, behavioral expression. Motor/sensory maps Parietal Lobe - ANSWER Sensation, optic radiations carrying sensory input from the eyes, language centers typically left side of brain Language Centers - ANSWER Broca's: Production/Expressive Wernicke's: Comprehension/Receptive

Occipital Lobe - ANSWER Vision and interpretation of visual sensory signals Dysarthria - ANSWER Slurred speech, reflecting poor motor control of the muscles associated with speech and language Temporal Lobe - ANSWER Coding visual memory and processing auditory and visual sensory input and language comprehension Basal Ganglia - ANSWER a group of nuclei serving as the coordinating center for several nerve tract including coordinating muscle movement Globus Pallidus - ANSWER A key component of the basal ganglia instrumental in control of voluntary muscle movement Limbic System - ANSWER a group of nuclei and cortical structures that encode memory and regulate autonomic nervous system and endocrine function in response to emotional situations Hypothalamus - ANSWER Coordinates autonomic nervous system with endocrine function, control of body temperature, circadian rhythm, and body water/osmolality Amygdala - ANSWER Plays a crucial role in the management of stress, rage, and anxiety. Center for memory and emotions.

Cingulate Gyrus - ANSWER develop emotions and encode memory Hippocampus - ANSWER Contains centers for memory and learning, regulation of corticosteroid production, and spatial relations Diencephalon - ANSWER Between the brain stem and cerebellum Thalamus - ANSWER The brain's sensory switchboard, located on top of the brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla Pineal Gland - ANSWER produces serotonin and melatonin - contributes to circadian rhythms Pituitary Gland - ANSWER Two Lobes Anterior: produces hormones Posterior: releases hormones Cerebellum - ANSWER Movement coordination and maintaining balance and position sense.

*Cannot initiate movement however is responsible for the unconscious coordination of movement. Brainstem - ANSWER Most basic neurologic functions and reflexes Midbrain - ANSWER Coordinates eye movement and reflexes associated with hearing and vision CNI: Olfactory: above the midbrain CNII: (s) Optic: Transmits visual cues (visual field deficits) CNIII: (M) Oculomotor: innervates 4 of the 6 muscles that move the eye, medially, upwards, outwards, downwards, pupillary constriction dilation and accommodation CNIV: (M) Trochlear: moves the eye downward and inward Pons - ANSWER Acts as a message center between cerebellum and cerebrum CNV: (M/S) Trigeminal: pain temp and light touch from the face, scalp, gag CNVI: (M) Abducens: Lateral gaze

CNVII: (M/S): Facial: innervates facial muscles CNVIII: (S) Vestibulocochlear: cochlear- hearing, Vestibular- balance Medulla - ANSWER The base of the brainstem; controls heartbeat and breathing CNIX : (M/S) Glossopharengeal: movement of pharynx and larynx, swallowing, taste on posterior tongue CNX: (M/S) Vagus: parasympathetic input to the neck thorax, and abdomen, sensor imput from external ear CNXI: (M) Accessory: motor impulses to pharynx and shoulders CNXII: (M) Hypoglossal: allows for control of the tongue muscles resulting in normal speech and swallow Somatosensory Tracts - ANSWER Pathways of neuronal communication 2 pathways System 1: Fine touch proprioception and vibration

System 2: Carries pain and temperature sensation from the periphery of the CNS Lock-In Syndrome - ANSWER Occlusion of the vertibrobasilar artery resulting in pontine damage - quadriplegic and cannot speak but cognition remains intact Small Vessel Stroke: Lacunar Infarct - ANSWER Approx. 25% of all strokes Caused by: Atherosclerosis, vasculitis, cerebral angiopathy Lacunar Syndrome

• Pure Motor hemiparesis
• Ataxic Hemiparesis
• Dysarthria and Clumsy Hands
• Pure Sensory stroke: unilateral numbness tingling or burning
• Mixed sensorimotor: hemiparesis with ipsilateral impairment without cortical signs e Watershed Strokes - ANSWER Caused by hypotension Reversible Cerebral Vasoconstriction Syndrome (RCVS) - ANSWER A genetic condition causing vessels to constrict.

Intercranial Hemorrhage - ANSWER Intraparenchymal hemorrhage symptom presentation generally associated with the location of hemorrhage Deep Hemorrhage: rapid decline in LOC, lateral focal neurologic deficits -- often associated with hypertension, and may be caused by vascular malformations or coagulopathy Lobar Hemorrhage: signs and symptoms related to lobar location -- more often associated with amyloid angiopathy, mass with associated with hemorrhage, or vascular malformation Subarachnoid Hemorrhage Cause - ANSWER Caused by head trauma, aneurysm rupture, vasculitis, infectious vascular abnormalities, and stimulant drug use Aneurysmal Subarachnoid Hemorrhage - ANSWER - Form at bifurcations

• 85% anterior
• Classification by morphology (85% saccular, fusiform)
• Sudden onset of a headache, LOC, nausea, vomiting, syncope, focal neurologic deficits Kernig's Signs: When thigh is flexed at the hip and extension of the knee is painful

Brudzinski's sign: when supine patient exhibits an involuntary lifting of the leg when the head is lifted. Sentinal headache: severe headache reported in the days or weeks before aSAH (15 - 60%) Non Aneurysmal SAH - ANSWER Approx: 15% Rarely experience cerebral vasospasm better outcomes overall Stroke Mimics - ANSWER 6 - 20% of suspected stroke patients toxic metabolic syndromes (hypoglycemia, hyponatremia, hepatic encepalopathy) Seziures disorders - esp. post ictal Todd's paralysis Migraines Headache Degenerative neurologic condition (MS)

Risk Factors: Ischemic Strokes - ANSWER Non Modifiable:

• Age
• Sex
• Low Birth Weight
• Face and Ethnicity
• Genetic Factors Modifiable
• Hypertension: treating hypertension is associated with 35 - 35% risk reduction
• Obesity
• Smoking: Doubles risk
• Diet and Nutrition (DASH)
• Physical Inactivity
• Limit Alcohol (2 drinks men, 1 drink women)
• Diabetes as defined as ---- Normal fasting < 100 ---- Impaired fasting 100 - 125 ---- Fasting Glucose > 126 ---- HgA1C > 6.5%
• Dyslipidemia 33.5% Americans have elevted LDL (goal < 70)
• Atrial Fibrillation
• Asymptomatic Carotid Artery Stenosis

• Post Menopausal Hormone Therapy
• Oral Contraceptive Use Potentially Modifiable
• Migraine Headaches
• Sleep-disorderd breathing Intracranial Hemorrhage Risk Factor - ANSWER Non Modifiable
• Age
• Sex
• Race
• Genetics Modifiable
• Hypertension
• High Alcohol Intake
• Oral Anticoagulation Therapy
• Use of Sympathomimetic Drugs
• Hemorrhagic Transformation of Ischemic Stroke
• Reperfusion Syndrome
• Smoking
• Diabetes
• Hypercholesterolemia

Aneurysmal Subarachnoid Hemorrhage Risk Factor - ANSWER Non Modifiable

• Sex
• Age
• Race
• Genetics Modifiable
• Smoking
• Heavy Alcohol Intake
• Hypertension
• Sympathomimetic Drug Use
• BMI
• Diet
• Increase Caffeine Intake
• Unruptured Cerebral Aneurysm Goals of EMS - ANSWER Rapid evaluation Early Stabilization Neurologic evaluation

--- Cinicinnati prehospital stroke scale --- Los Angeles prehospital stoke screen ED: Goal Action Times - ANSWER Door to Physician: < 10 minutes Door to Stroke Team < 15 minutes Door to CT initiation < 25 minutes Door to CT interpretation < 45 minutes Door to Alteplase < 60 minutes Stroke score - ANSWER Calculate Stroke Scores in ED NIHSS: Ischemic Stroke Hunt Hess & Fisher: SAH ICH score: ICH Acute Treatment of Ischemic Stoke - ANSWER IV tPa

• criteria

• dosing Post Administration care Identify Post Administration Complications
• symptomatic ICH
• bleeding from another site
• Angioedema Interventional Treatment of Ischemic stroke (Door to IA 90 - 120 minutes)
• IA tPa
• Mechanical Thrombectomy (within 6 hours of stroke) -- coil retrievers -- Aspiration/debulking system -- Stent retrievers Hemicraniectomy tPa Criteria - ANSWER 3 hours
• No trauma or stroke in 3 months
• sx suggesting SAH
• no Hx of IPH, anyurysm, or tumor

• No acute bleeding
• No Platelets < 100,
• No heparin < 24hrs. or PTT > normal
• INR > 1.7 or PT > 15
• No current use of oral anticoagulant
• No BG < 50
• No hypodensity of > 1/3 of the brain 4.5 hours
• No age > 80
• No NIHSS > 25
• No anticoagulation
• No hx of diabetes or stroke Relative Contradictions
• minor or rapidly improving stroke sx
• Pregnancy
• Seizures at onset
• Recent GI or Urinary tract hemorrhage (21 days)
• Recent MI (w/in 3 months) tPa Dosing - ANSWER 0.9 mg/kg

10% administered over 1 minute. Remainder over an hour MAX DOSE: 90 mg Acute Interventions for Hemorrhagic Strokes - ANSWER Correct coagulopathies Understand need for ventriculostomy -- in ICH EVD used for pts with GCS < 8 or for those with IVH, hydrocephalus, or s/s or hermiation Manage ICP Non Enhanced CT - ANSWER Parenchymal brain imaging -- computer processed x rays to yield cross sectional imagines CT Perfusion - ANSWER Cerebral perfusion can be observed recorded and quantified CT-A - ANSWER 3D rendering of vessel anatomy MRI - ANSWER Can measure infarct cor and penumbra adding valuable information in the consideration for reperfusion therapy MR Spectroscpoy - ANSWER a technique that investigates

metabolic changes in brain disorders MR- Perfusion - ANSWER Measure cerebral perfusion via assessment of various hemodynamic measurements such as cerebral blood volume, cerebral blood flow, and mean transit time. Cerebral Angiography - ANSWER Post procedure monitoring should include monitoring for bleeding, hematoma, or impaired circulation including pulses. 6 hours flat unless a collagen closure device is used Assess for chest pain or shortness of breath s/p procedure Transcranial dopplers - ANSWER 2D ultrasound imagining to measure blood flow velocities over time Identifies intracranial vessel abnormalities, occlusion, and stenosis Transthoracic Echocardiogram - ANSWER Cardiac ultrasound to assess heart valves, degree of heart muscle contraction, strength and condition of the lining of the heart and aorta Transesophageal Echocardiogram - ANSWER Ultrasound of the heart through the lining of the esophagus

NPO for 6 hours Electroencephalogram (EEG) - ANSWER 24 noninvasive scalp electrodes to capture and record electrical fluctuations that occur within the cerebral neurons utilized for the diagnosis and analysis of convulsive and nonconvulsive seizures Some evidence suggests continuous EEG may detect delayed ischemia associated with cerebral vasospasm Electrocardiogram - ANSWER A snapshot of the electrical activity of the heart such as rate and regularity Carotid Doppler Ultrasound - ANSWER Noninvasive ultrasound capable of detecting degree of stenosis at the origin of the internal carotid artery Lumbar Puncture - ANSWER Puncture at the level of L3/L4 or L4/L5 to obtain cerebral spinal fluid for diagnostic purposes or to measure CSF pressure Glascow Coma Scale (GCS) - ANSWER Most widely used coma scale Eye opening, Verbal response, motor response

FOUR score - ANSWER Eye reaction, motor function, brain stem reflexes, and respiratory pattern National Institutes of Health Stroke Scale (NIHSS) - ANSWER Quantitatively measures 15 neurological assessment items Score correlates with infarct volumes Score is predictive of outcome at 7 days and 2 months -- Score 7 - 13 predictive of inpatient rehab -- Score of 14 or more requiring acute care facility Israeli Vertebrobasilar Stroke Scale - ANSWER 11 item scale that incorporate posterior circulation s/s such as diplopia, dysphagia, and gait instability ICH Score - ANSWER Score of 1 - 6 graded on admission GCS, intitial hematoma volume, presence of IVH, infraentorial location of the bleed and age Hunt and Hess Score - ANSWER 0 - unruptured 1 - minimal HA and nuchal rigidity (5%) 2 - mod-sev headache, nuchal rigidity, no neuro defecit (10%)

3 - + above and drowsiness/confusion and mild defecit (30%) 4 - stupur, hemipareisis, mild decerebration 5 - comatose, decerebreation, rigidity Fisher Scale - ANSWER Score 1 - 4 based on assessment of blood volume ABCD score - ANSWER risk assessment tool used with TIA patients to assess their risk of strokes Modified Rankin Scale (mRS) - ANSWER Measures comprehensive stroke outcomes Measures functional independence - 0 (no symptoms) to 6 (clinically dead) Barthel Index - ANSWER Self-care and mobility scale 100 is normal lower the score the higher the disability and dependency Functional Independence Measure - ANSWER Measures 18 ADLs ranked 1 to 7

1 total assist 7 complete independence Acute Care Diagnostic Testing - ANSWER Noncontrast CT Imaging MRI Angiography Carotid Doppler Transcranial Doopler Echocardiogram Acute Stroke Care - ANSWER Frequent neuro assessment and vital signs Cardiac monitoring and BP goals Proper oxygenation > 94% Early mobilization Pain assessment and management Blood glucose management

Targeted Temperature Management Hyperglycemia in strokes - ANSWER Hyperglycemia occurs in 30 - 40% of all stroke patients Injured brain does not tolerate hyperglycemia and inflammatory response Pts with hyperglycemia after stroke have worse outcomes In SAH prolonged hyperglycemia is a predictor of death In ICH hyperglycemia in the first 72 hours is associated with increased mortality Targeted Temperature Mangement - ANSWER Fever independently contributes to death and disability at 30 days in stroke, ICH, and SAH Pharmacological interventions include Acetaminophen: With attention to total dose per day and liver function

Ibuprofen: with attention to renal function and potential impact on platelet functions Buspirone: anti-shivering properties Magnesium: promotes mild muscle relaxation Dantrolene: decreases amplitube of shivering response Merperidine: the only opiate with antishivering characteristics Safety Measures for Stroke Patients - ANSWER Aspiration risk: swallow function assessment/evidence swallow strategies Fall Precautions: use fall assessment tools/proactive universal fall precautions Seizures Precautions -- Ischemic: routes use of seizure prophylaxis associated with worse patient outcomes -- ICH at highest risk for seizures in first 24 hours

• --- Prophylactic AEDs should not be used -- SAH: as high as 20% --- Start seizure prophylaxis for 3 - 7 days