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Neurolo Neurolo gy gy Chapter #31 Chapter #31 Jason N. Cook Jason N. Cook Emergency Care & Rescu Emergency Care & Rescu Weber State University Weber State University

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Page 1: Neurology

NeurologyNeurologyChapter #31Chapter #31

Jason N. CookJason N. CookEmergency Care & RescueEmergency Care & Rescue

Weber State UniversityWeber State University

Page 2: Neurology

Pathophysiology of CNS Pathophysiology of CNS EmergenciesEmergencies

Structural ChangesStructural Changes Often due to Trauma but not alwaysOften due to Trauma but not always Circulatory ChangesCirculatory Changes

• Inadequate PerfusionInadequate Perfusion

Alterations of ICPAlterations of ICP• Response to insultResponse to insult

Toxic Metabolic statesToxic Metabolic states Alteration to blood chemistry or introduction of toxinsAlteration to blood chemistry or introduction of toxins

Psychiatric ‘mimicking’Psychiatric ‘mimicking’

Page 3: Neurology

Nervous System AnatomyNervous System Anatomy Two partsTwo parts

Central nervous system Central nervous system (CNS)(CNS)

Peripheral nervous system Peripheral nervous system (PNS)(PNS)

CNSCNS BrainBrain Spinal cordSpinal cord

• Both encased in and Both encased in and protected by boneprotected by bone

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Page 4: Neurology

Peripheral Nervous SystemPeripheral Nervous System 43 pairs of nerves 43 pairs of nerves

originate from CNS to originate from CNS to form PNSform PNS 12 pairs of cranial nerves12 pairs of cranial nerves

• Originate from brainOriginate from brain 31 pairs of spinal nerves31 pairs of spinal nerves

• Originate from spinal cordOriginate from spinal cord

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Page 5: Neurology

Cells of the Nervous SystemCells of the Nervous System Neurons—fundamental units Neurons—fundamental units

Neuroglia—connective tissue cellsNeuroglia—connective tissue cells Protect and hold neurons togetherProtect and hold neurons together

NeuronsNeurons Cell body—single nucleus and nucleolusCell body—single nucleus and nucleolus Dendrites—branching projections Dendrites—branching projections Axon—single, elongated projectionAxon—single, elongated projection

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Page 6: Neurology

Cells of the Nervous SystemCells of the Nervous System

Neuron with dendrites,Neuron with dendrites,cell body, axoncell body, axon

Neuron

Page 7: Neurology

Cells of the Nervous SystemCells of the Nervous System Dendrites transmit impulses Dendrites transmit impulses toto neuron cell neuron cell

bodiesbodies

Axons transmit impulses Axons transmit impulses away from away from cell cell bodiesbodies Bundles of parallel axons with sheaths are white Bundles of parallel axons with sheaths are white

• White matterWhite matter

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Page 8: Neurology

Cells of the Nervous SystemCells of the Nervous System In PNS, bundles of axons and their sheaths In PNS, bundles of axons and their sheaths

are called are called nervesnerves Collections of nerve cells are gray Collections of nerve cells are gray

• Gray matterGray matter

Gray matter is integration site within nervous Gray matter is integration site within nervous systemsystem

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Page 9: Neurology

Types of NeuronsTypes of Neurons Classified by impulse transmission direction:Classified by impulse transmission direction:

Sensory neuronsSensory neurons• Afferent neuronsAfferent neurons

Motor neuronsMotor neurons• Efforent neuronsEfforent neurons

InterneuronsInterneurons• Connecting neuronsConnecting neurons

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Page 10: Neurology

Impulse TransmissionImpulse Transmission Nervous system transmission similar to Nervous system transmission similar to

electrical impulse conduction in heartelectrical impulse conduction in heart

Unmyelinated axonsUnmyelinated axons

Myelinated axonsMyelinated axons

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Page 11: Neurology

Nerve Impulse ConductionNerve Impulse Conduction

Unmyelinated fiberUnmyelinated fiber

Myelinated fiberMyelinated fiber

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Page 12: Neurology

SynapseSynapse Membrane-to-membrane contactMembrane-to-membrane contact

Separates axon endings of one neuron (presynaptic Separates axon endings of one neuron (presynaptic neuron) from dendrites of another neuron neuron) from dendrites of another neuron (postsynaptic neuron)(postsynaptic neuron) Presynaptic terminalPresynaptic terminal Synaptic cleftSynaptic cleft Plasma membrane of postsynaptic neuronPlasma membrane of postsynaptic neuron

Presynaptic terminals have synaptic vesicles Presynaptic terminals have synaptic vesicles containing neurotransmitter chemicals containing neurotransmitter chemicals

NeurotransmittersNeurotransmitters

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Page 13: Neurology

Components of a Synapse Components of a Synapse

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Page 14: Neurology

ReflexesReflexes Receive stimulus and generate responseReceive stimulus and generate response

Unidirectional impulse conductionUnidirectional impulse conduction• Sensory receptorSensory receptor

• Sensory neuronSensory neuron

• InterneuronsInterneurons

• Motor neuronMotor neuron

• Effector organEffector organ

Vary in complexityVary in complexity

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Page 15: Neurology

Neural Pathway Involved inNeural Pathway Involved inPatellar (“Knee Jerk” ) ReflexPatellar (“Knee Jerk” ) Reflex

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Page 16: Neurology

Blood SupplyBlood Supply Arterial blood supply to brainArterial blood supply to brain

Vertebral arteriesVertebral arteries Internal carotid arteriesInternal carotid arteries

Circle of WillisCircle of Willis Safeguard to ensure blood supply to all parts of Safeguard to ensure blood supply to all parts of

the brain if vertebral or internal carotid arteries are the brain if vertebral or internal carotid arteries are blockedblocked

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Page 17: Neurology

Blood SupplyBlood Supply

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Page 18: Neurology

VeinsVeins Veins that drain blood from head form venous Veins that drain blood from head form venous

sinusessinuses

Drain into internal jugular veinsDrain into internal jugular veins

Internal jugular veins join subclavian veins on Internal jugular veins join subclavian veins on each side of the bodyeach side of the body

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Page 19: Neurology

Venous Sinuses AssociatedVenous Sinuses Associatedwith the Brainwith the Brain

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Page 20: Neurology

Ventricles of the BrainVentricles of the Brain Lateral ventricleLateral ventricle

Space in cerebral Space in cerebral hemispheres is filled hemispheres is filled with cerebrospinal fluidwith cerebrospinal fluid

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Page 21: Neurology

Divisions of the Adult BrainDivisions of the Adult Brain Brain stemBrain stem

MedullaMedulla PonsPons MidbrainMidbrain

CerebellumCerebellum

DiencephalonDiencephalon HypothalamusHypothalamus ThalamusThalamus

CerebrumCerebrum

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Page 22: Neurology

Neurological PathophysiologyNeurological Pathophysiology Cerebral blood flow (CBF) interrupted by:Cerebral blood flow (CBF) interrupted by:

Structural changes or damageStructural changes or damage Circulatory changesCirculatory changes Alterations in intracranial pressure (ICP)Alterations in intracranial pressure (ICP)

Three structures in intracranial space:Three structures in intracranial space: Brain tissueBrain tissue BloodBlood WaterWater

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Page 23: Neurology

Intracranial SpaceIntracranial Space Brain tissueBrain tissue

Mostly water, intracellular and extracellularMostly water, intracellular and extracellular

BloodBlood Major arteries in base of brainMajor arteries in base of brain Arterial branches, arterioles, capillaries, Arterial branches, arterioles, capillaries,

venules, veins within brain substance venules, veins within brain substance Cortical veins and dural sinusesCortical veins and dural sinuses

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Page 24: Neurology

Intracranial SpaceIntracranial Space Water in:Water in:

Ventricles of brainVentricles of brain Cerebrospinal fluidCerebrospinal fluid Extracellular and intracellular fluidExtracellular and intracellular fluid

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Page 25: Neurology

Cerebral Perfusion Pressure (CPP)Cerebral Perfusion Pressure (CPP)

Cerebral blood flow depends on cerebral Cerebral blood flow depends on cerebral perfusion pressureperfusion pressure Pressure gradient across brainPressure gradient across brain

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Page 26: Neurology

Cerebral Blood FlowCerebral Blood Flow Cerebral blood flow controls oxygen and Cerebral blood flow controls oxygen and

glucose deliveryglucose delivery Cerebral perfusion pressure (CPP) and cerebral Cerebral perfusion pressure (CPP) and cerebral

vascular bed resistancevascular bed resistance CPP determined by:CPP determined by:

• Mean arterial pressure (MAP): (Diastolic pressure + Mean arterial pressure (MAP): (Diastolic pressure + ⅓⅓ pulse pressure) minus intracranial pressurepulse pressure) minus intracranial pressure

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Page 27: Neurology

Cerebral Blood FlowCerebral Blood Flow As ICP approaches MAP:As ICP approaches MAP:

Gradient for flow decreasesGradient for flow decreases Cerebral blood flow restrictedCerebral blood flow restricted

When ICP increases, CPP decreasesWhen ICP increases, CPP decreases As CPP decreases, cerebral vasodilation As CPP decreases, cerebral vasodilation Increases cerebral blood volume (increasing Increases cerebral blood volume (increasing

ICP) and further cerebral vasodilationICP) and further cerebral vasodilation

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Page 28: Neurology

ICP ReviewICP Review CBF (Cerebral Blood Flow) is a factor of CPP CBF (Cerebral Blood Flow) is a factor of CPP

(Cerebral Perfusion Pressure) & CVR (Cerebral Perfusion Pressure) & CVR (Cerebral Vascular Resistance)(Cerebral Vascular Resistance) If CPP If CPP , then CBF , then CBF If CVR If CVR , then CBF most likely , then CBF most likely

CPP = MAP - ICPCPP = MAP - ICP MAP = Diastolic + 1/3 PPMAP = Diastolic + 1/3 PP PP = SBP - DBPPP = SBP - DBP

PCOPCO22 has greatest effect on CVR has greatest effect on CVR Sympathomimetics may Sympathomimetics may CVR CVR

Page 29: Neurology

ICP ReviewICP Review As PCOAs PCO22 , CVR , CVR

Therefore, if PCOTherefore, if PCO22 , CVR , CVR Then, as CVR Then, as CVR , CBF , CBF

Normal ICP < 15 mm HgNormal ICP < 15 mm Hg As ICP As ICP , CPP , CPP then CBF then CBF Compensation for Compensation for ICP via ICP via MAP MAP

Cushing’s Reflex (Triad)Cushing’s Reflex (Triad) Cushing’s triad with coma indicates possible Cushing’s triad with coma indicates possible

herniationherniation

Page 30: Neurology

Is unconsciousness itself an Is unconsciousness itself an immediate life threat?immediate life threat?

Loss of airwayLoss of airway Vomiting, aspirationVomiting, aspiration

YES, IT IS!

Page 31: Neurology

Altered Mental StateAltered Mental State

Manage ABC’s Before Investigating Cause!

Page 32: Neurology

Goals of Emergency CareGoals of Emergency Care Airway controlAirway control

Stabilization and support of cardiovascular systemStabilization and support of cardiovascular system

Intervention to interrupt ongoing cerebral injuryIntervention to interrupt ongoing cerebral injury

Protection from further harmProtection from further harm

Transport to an appropriate medical facilityTransport to an appropriate medical facility

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Page 33: Neurology

Initial AssessmentInitial Assessment Level of consciousnessLevel of consciousness

Ensure patent airwayEnsure patent airway

Immobilize cervical spineImmobilize cervical spine

Airway adjuncts if indicatedAirway adjuncts if indicated Monitor for respiratory arrestMonitor for respiratory arrest

Ventilatory support and supplemental oxygen for any Ventilatory support and supplemental oxygen for any neurological emergencyneurological emergency

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Page 34: Neurology

Initial Initial Assessment/ManagementAssessment/Management

AirwayAirway Open, clear, maintainOpen, clear, maintain If trauma or If trauma or ++ history, control C-spine history, control C-spine

BreathingBreathing Presence? Adequacy (rate, tidal volume)?Presence? Adequacy (rate, tidal volume)? High concentration OHigh concentration O22 on on ALLALL patients with altered patients with altered

mental statusmental status Assist ventilations prnAssist ventilations prn

CirculationCirculation Pulses? Adequate Perfusion?Pulses? Adequate Perfusion?

Page 35: Neurology

HistoryHistory History of event from patient, family, History of event from patient, family,

bystandersbystanders

If loss of consciousness, ascertain events prior If loss of consciousness, ascertain events prior to unconscious state:to unconscious state: Patient position (sitting, standing, lying down)Patient position (sitting, standing, lying down) Complaints of a headacheComplaints of a headache Seizure activitySeizure activity FallFall

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Page 36: Neurology

HistoryHistory When no history is available, assume the When no history is available, assume the

onset of unconsciousness was acute and that onset of unconsciousness was acute and that an intracranial hemorrhage is likelyan intracranial hemorrhage is likely

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Page 37: Neurology

Investigate CauseInvestigate Cause DERMDERM

DD = Depth of Coma = Depth of Coma EE = Eyes = Eyes RR = Respiratory Pattern = Respiratory Pattern MM = Motor Function = Motor Function

Page 38: Neurology

D = Depth of ComaD = Depth of Coma What does patient respond to?What does patient respond to? How does he respond?How does he respond?

Avoid use of non-specific terms like “stuporous”, “semi-conscious”, “lethargic”,

“obtunded”

Page 39: Neurology

D = Depth of ComaD = Depth of Coma

AVPUAVPU Glasgow Scale (later)Glasgow Scale (later)

Describe level of consciousness in terms of

reproducible findings

Page 40: Neurology

Neurological EvaluationNeurological Evaluation AVPU and Glasgow Coma ScaleAVPU and Glasgow Coma Scale

Determine baseline neurological statusDetermine baseline neurological status Allow comparisonsAllow comparisons

Report and record patient information with Report and record patient information with specific descriptive termsspecific descriptive terms

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Page 41: Neurology

E = EyesE = Eyes PupilsPupils

Size - mid, dilated or constrictedSize - mid, dilated or constricted• measurement - e.g. 4 mmmeasurement - e.g. 4 mm

Shape - round, oval, pontineShape - round, oval, pontine Equality - equal in sizeEquality - equal in size Symmetry - equal in reaction/responseSymmetry - equal in reaction/response Response to lightResponse to light

• Yes or NoYes or No

• How? How?

Page 42: Neurology

Pupils at DifferentPupils at DifferentLevels of ConsciousnessLevels of Consciousness

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Page 43: Neurology

Extraocular MovementsExtraocular Movements Conjugate gazeConjugate gaze

A deviation of both eyes A deviation of both eyes to either side.to either side.• Irritative focusIrritative focus

• Destructive focusDestructive focus

Dysconjugate gazeDysconjugate gaze Deviation of the eyes to Deviation of the eyes to

opposite sidesopposite sides• Brain Stem injuryBrain Stem injury

Page 44: Neurology

R = Respiratory PatternR = Respiratory Pattern

DepthDepth Unusually deep or shallow?Unusually deep or shallow?

PatternPattern Regular or Unusual patternRegular or Unusual pattern

• Can you identify the pattern?Can you identify the pattern?

Page 45: Neurology

Respiratory PatternsRespiratory Patterns Normal or abnormalNormal or abnormal

Abnormal respiratory patternsAbnormal respiratory patterns Cheyne-Stokes respirationCheyne-Stokes respiration Central neurogenic hyperventilationCentral neurogenic hyperventilation Ataxic respirationAtaxic respiration Apneustic respirationApneustic respiration Diaphragmatic breathingDiaphragmatic breathing

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Page 46: Neurology

Respiratory PatternsRespiratory Patterns

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Page 47: Neurology

M = Motor FunctionM = Motor Function Paralysis?Paralysis?

Where?Where? Muscle tone? Muscle tone?

Rigid or FlaccidRigid or Flaccid Movement?Movement?

Where? What is it like?Where? What is it like? Posturing? Posturing?

How?How? Symmetrical Motor Function?Symmetrical Motor Function?

Page 48: Neurology

Posturing, Muscle Tone, and ParalysisPosturing, Muscle Tone, and Paralysis

Disturbances of posture result from:Disturbances of posture result from: Flexor spasmsFlexor spasms Extensor spasmsExtensor spasms FlaccidityFlaccidity

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Page 49: Neurology

Posturing, Muscle Tone, and ParalysisPosturing, Muscle Tone, and Paralysis

Decorticate rigidityDecorticate rigidity FlexionFlexion Abnormal flexor responses of one or both arms Abnormal flexor responses of one or both arms

with extension of legswith extension of legs Structural impairment of certain cortical regions of Structural impairment of certain cortical regions of

brainbrain

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Page 50: Neurology

Posturing, Muscle Tone, and ParalysisPosturing, Muscle Tone, and Paralysis

Decerebrate rigidityDecerebrate rigidity ExtensionExtension Abnormal extensor response of arms and legs Abnormal extensor response of arms and legs Worse prognosis than decorticate rigidityWorse prognosis than decorticate rigidity Impairment of subcortical regions of brainImpairment of subcortical regions of brain

FlaccidityFlaccidity Brain stem or cord dysfunctionBrain stem or cord dysfunction Dismal prognosisDismal prognosis

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Page 51: Neurology

PosturingPosturing

Abnormal extension (decerebrate posturing)

Abnormal flexion (decorticate posturing)

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Page 52: Neurology

Assessment—Abnormal ReflexesAssessment—Abnormal Reflexes

Positive Babinski's signPositive Babinski's sign Plantar reflexPlantar reflex Dorsiflexion of great toe Dorsiflexion of great toe

with or without fanning of with or without fanning of toestoes

Relaxation of sphincter Relaxation of sphincter tone with evacuation of tone with evacuation of bowels and/or bladderbowels and/or bladder

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Page 53: Neurology

Vital SignsVital Signs Assess and record frequentlyAssess and record frequently

May change rapidly May change rapidly Monitor ECG for dysrhythmiasMonitor ECG for dysrhythmias

Cushing’s triad, if increased ICP:Cushing’s triad, if increased ICP: Increase in systolic pressure (widening pulse Increase in systolic pressure (widening pulse

pressure)pressure) Decrease in pulse rateDecrease in pulse rate Irregular respiratory patternIrregular respiratory pattern

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Page 54: Neurology

Physical ExamPhysical Exam Vital SignsVital Signs

Shock? Shock? Increased ICP? Increased ICP? Hypoxia/HypercarbiaHypoxia/Hypercarbia

DiagnosticsDiagnostics Dysrhythmias?Dysrhythmias? Blood glucoseBlood glucose Oxygen saturationOxygen saturation

Page 55: Neurology

Physical ExamPhysical Exam Detailed (Head-to-Toe) ExamDetailed (Head-to-Toe) Exam

Injuries causing coma?Injuries causing coma? Injuries caused by coma?Injuries caused by coma? Clues to the causeClues to the cause

Page 56: Neurology

Probable Causes of AMSProbable Causes of AMS Not enough Not enough OxygenOxygen Not enough Not enough SugarSugar Not enough Not enough blood flowblood flow to deliver oxygen, to deliver oxygen,

sugarsugar Direct brain Direct brain injuryinjury

StructuralStructural MetabolicMetabolic

Page 57: Neurology

Differentiating AMS CausesDifferentiating AMS Causes StructuralStructural

Asymmetrical Asymmetrical deficitsdeficits

Unequal pupilsUnequal pupils AfebrileAfebrile History of trauma, History of trauma,

structural structural abnormalityabnormality

Often a rapid Often a rapid onsetonset

MetabolicMetabolic Symmetrical deficitsSymmetrical deficits Equal pupils Equal pupils

(? altered function)(? altered function) ? Fever? Fever History of metabolic History of metabolic

disorder or illnessdisorder or illness Rapid onset less Rapid onset less

likelylikely

Page 58: Neurology

ManagementManagement Maintain ABCsMaintain ABCs Attempt to identify causeAttempt to identify cause Mainstays of therapyMainstays of therapy

Oxygenation/VentilationOxygenation/Ventilation IV fluids appropriate for the patientIV fluids appropriate for the patient D50 (if hypoglycemic)D50 (if hypoglycemic) Narcan if possibility of opiate ODNarcan if possibility of opiate OD Flumazenil in known benzo only ODFlumazenil in known benzo only OD

Page 59: Neurology
Page 60: Neurology

ComaComa A decreased state of consciousness A decreased state of consciousness

from which a patient cannot be arousedfrom which a patient cannot be aroused

MechanismsMechanisms Structural lesionsStructural lesions Toxic Metabolic statesToxic Metabolic states Psychiatric ‘mimicking’Psychiatric ‘mimicking’

Page 61: Neurology

Brain injuryBrain injury Recall that Brain injury is often shown by:Recall that Brain injury is often shown by:

Altered Mental StatusAltered Mental Status SeizuresSeizures Localizing signsLocalizing signs

Page 62: Neurology

Stroke and Intracranial HemorrhageStroke and Intracranial Hemorrhage

Stroke (“brain attack”)Stroke (“brain attack”)

Sudden interruption in brain blood flow Sudden interruption in brain blood flow

Results in neurological deficitResults in neurological deficit IncidenceIncidence Morbidity/mortalityMorbidity/mortality Risk factorsRisk factors

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Page 63: Neurology

Stroke PathophysiologyStroke Pathophysiology Blood supply to brain through Blood supply to brain through

four vesselsfour vessels Carotid arteriesCarotid arteries

• 80% of cerebral blood flow80% of cerebral blood flow Vertebral arteriesVertebral arteries

• Form basilar arteryForm basilar artery• 20% of cerebral blood flow20% of cerebral blood flow

Interconnected at various Interconnected at various levelslevels• Circle of WillisCircle of Willis

Onset and symptoms depend Onset and symptoms depend on area of brain involvedon area of brain involved

Page 64: Neurology

Types of StrokeTypes of Stroke Neurological manifestations of Neurological manifestations of

decrease in blood flow to braindecrease in blood flow to brain Ischemic and hemorrhagic Ischemic and hemorrhagic

strokesstrokes Both can be life threateningBoth can be life threatening Ischemic stroke rarely causes death Ischemic stroke rarely causes death

in first hourin first hour Hemorrhagic stroke can be rapidly Hemorrhagic stroke can be rapidly

fatalfatal

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Page 65: Neurology

Ischemic StrokeIschemic Stroke 85% of strokes are 85% of strokes are

ischemicischemic Cerebral thrombosis due Cerebral thrombosis due

to:to: Atherosclerotic plaquesAtherosclerotic plaques Extrinsic pressure brain Extrinsic pressure brain

massmass Thrombotic strokeThrombotic stroke

Slower to develop than Slower to develop than cerebral hemorrhagecerebral hemorrhage

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Page 66: Neurology

Cerebral EmbolusCerebral Embolus Intracranial vessel occluded by foreign Intracranial vessel occluded by foreign

substance from outside CNS.substance from outside CNS. Signs and symptomsSigns and symptoms

Similar to thrombotic strokeSimilar to thrombotic stroke Usually develop more quicklyUsually develop more quickly Often have identifiable causeOften have identifiable cause

Page 67: Neurology

Hemorrhagic StrokeHemorrhagic Stroke IncidenceIncidence

Morbidity/mortalityMorbidity/mortality

CausesCauses Cerebral aneurysmsCerebral aneurysms Arteriovenous (AV) Arteriovenous (AV)

malformationsmalformations HypertensionHypertension

Signs and symptomsSigns and symptoms

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Page 68: Neurology

Transient Ischemic AttacksTransient Ischemic Attacks Focal cerebral dysfunction lasting from minutes Focal cerebral dysfunction lasting from minutes

to several hoursto several hours

Return to normal Return to normal <<24 hrs24 hrs

No permanent neurological deficitNo permanent neurological deficit Indication of impending strokeIndication of impending stroke

Signs and symptomsSigns and symptoms

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Page 69: Neurology

Differentiating between Ischemic and Differentiating between Ischemic and Hemorrhagic StrokeHemorrhagic Stroke

Ischemic StrokeIschemic Stroke Hemorrhagic StrokeHemorrhagic Stroke

Most commonMost common Least commonLeast common

Atherosclerosis or tumor within Atherosclerosis or tumor within brainbrain

Cerebral aneurysms, AV Cerebral aneurysms, AV malformations, hypertensionmalformations, hypertension

Slow onsetSlow onset Abrupt onsetAbrupt onset

Long history of vessel diseaseLong history of vessel disease Stress or exertionStress or exertion

Valvular heart disease and atrial Valvular heart disease and atrial fibrillationfibrillation

Cocaine and other Cocaine and other sympathomimetic aminessympathomimetic amines

Hx of angina, previous strokesHx of angina, previous strokes May be asymptomatic before May be asymptomatic before rupturerupture

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Page 70: Neurology

AssessmentAssessment Emergency care prioritiesEmergency care priorities

Maintain patent airwayMaintain patent airway Provide adequate ventilatory supportProvide adequate ventilatory support OxygenOxygen Thorough historyThorough history

ManagementManagement Time in field must be reducedTime in field must be reduced Establish time of symptom onset (if possible)Establish time of symptom onset (if possible) Supportive measuresSupportive measures

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Page 71: Neurology

Cincinnati Prehospital Stroke Cincinnati Prehospital Stroke ScaleScale

A simple version of the National Institutes of Health Stroke A simple version of the National Institutes of Health Stroke ScaleScale

Accurate in identifying patients with strokeAccurate in identifying patients with stroke An abnormal finding in ANY of the three tests strongly suggests An abnormal finding in ANY of the three tests strongly suggests

a stroke. a stroke.

Facial DroopFacial Droop Arm DriftArm Drift Slurred SpeechSlurred Speech

Page 72: Neurology

Los Angeles Prehospital Stroke Screen Los Angeles Prehospital Stroke Screen (LAPSS)(LAPSS)

AgeAge HistoryHistory Symptom durationSymptom duration Baseline disabilityBaseline disability

Identifies asymmetry in:Identifies asymmetry in:• Facial smile/grimaceFacial smile/grimace

• GripGrip

• Arm strengthArm strength

Asymmetry in any category indicates a possible strokeAsymmetry in any category indicates a possible stroke

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Page 73: Neurology

Prehospital Stroke ManagementPrehospital Stroke Management

Rapid transportRapid transport Determine time of symptom onsetDetermine time of symptom onset Manage airwayManage airway Oxygen if SaO2 <92%Oxygen if SaO2 <92% Monitor vital signs and ECGMonitor vital signs and ECG Initiate IV en routeInitiate IV en route Assess blood glucoseAssess blood glucose Control seizures with benzodiazepinesControl seizures with benzodiazepines

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Page 74: Neurology

HeadacheHeadache Categorized by underlying cause:Categorized by underlying cause:

Tension headachesTension headaches MigrainesMigraines Cluster headachesCluster headaches Sinus headachesSinus headaches

Common medical complaintCommon medical complaint

Page 75: Neurology

Tension HeadachesTension Headaches Muscle contractions of face, neck, scalpMuscle contractions of face, neck, scalp

CausesCauses

Signs and symptomsSigns and symptoms

ManagementManagement

Page 76: Neurology

MigrainesMigraines Severe, incapacitating headachesSevere, incapacitating headaches

Often preceded by visual or GI disturbancesOften preceded by visual or GI disturbances

Intense, throbbing pain on one side of headIntense, throbbing pain on one side of head May spreadMay spread Often nausea and vomitingOften nausea and vomiting

Constriction and dilation of blood vesselsConstriction and dilation of blood vessels Imbalance of serotonin or hormone fluctuationsImbalance of serotonin or hormone fluctuations

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Page 77: Neurology

MigrainesMigraines Also triggered by:Also triggered by:

Excessive caffeine useExcessive caffeine use Various foodsVarious foods Changes in altitudeChanges in altitude Extremes of emotionsExtremes of emotions

ManagementManagement

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Page 78: Neurology

Cluster HeadachesCluster Headaches Occur in bursts (clusters)Occur in bursts (clusters)

Often several hours after asleepOften several hours after asleep

PainPain SevereSevere Usually around one eyeUsually around one eye Often nasal congestion and tearingOften nasal congestion and tearing Often lasts 30 min to 2 hrs, and recurs a day or so laterOften lasts 30 min to 2 hrs, and recurs a day or so later May occur every day for months before long periods of May occur every day for months before long periods of

remissionremission

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Page 79: Neurology

Cluster HeadachesCluster Headaches Histamine headachesHistamine headaches

Release of histamine from tissuesRelease of histamine from tissues SymptomsSymptoms

• Dilated carotid arteriesDilated carotid arteries

• Fluid accumulation under eyesFluid accumulation under eyes

• Tearing Tearing

• RhinorrheaRhinorrhea

ManagementManagement

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Page 80: Neurology

Sinus HeadachesSinus Headaches Pain in forehead, nasal area, and eyesPain in forehead, nasal area, and eyes

Feeling of pressure behind faceFeeling of pressure behind face

Inflammation or infection of membranes lining Inflammation or infection of membranes lining sinus cavities or allergiessinus cavities or allergies

ManagementManagement

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Page 81: Neurology

Brain NeoplasmBrain Neoplasm Mass in cranial cavityMass in cranial cavity

Malignant or benignMalignant or benign

Risk factorsRisk factors

Signs and symptomsSigns and symptoms

ManagementManagement

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Page 82: Neurology

Brain AbscessBrain Abscess Accumulation of purulent material (pus) Accumulation of purulent material (pus)

surrounded by a capsule within brainsurrounded by a capsule within brain

CausesCauses

Clinical manifestationsClinical manifestations

Management Management

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Page 83: Neurology

Muscular DystrophyMuscular Dystrophy Inherited muscle disorderInherited muscle disorder

Unknown causeUnknown cause

Slow, progressive degeneration of muscle Slow, progressive degeneration of muscle

Different forms classified by:Different forms classified by: Age symptoms appearAge symptoms appear Rate of disease progressionRate of disease progression How inheritedHow inherited

Duchenne muscular dystrophyDuchenne muscular dystrophy Most common typeMost common type

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Muscular Muscular DystrophyDystrophy

Page 85: Neurology

Multiple Sclerosis (MS)Multiple Sclerosis (MS) Progressive CNS disease Progressive CNS disease

Scattered patches of myelin in brain and Scattered patches of myelin in brain and spinal cord are destroyedspinal cord are destroyed CauseCause IncidenceIncidence Morbidity/mortalityMorbidity/mortality Clinical manifestationsClinical manifestations ManagementManagement

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Page 86: Neurology

DystoniaDystonia Local or diffuse alterations in muscle tone Local or diffuse alterations in muscle tone

Usually abnormal muscle rigidityUsually abnormal muscle rigidity

CausesCauses Painful muscle spasmsPainful muscle spasms Unusually fixed posturesUnusually fixed postures Strange movement patternsStrange movement patterns

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Page 87: Neurology

DystoniaDystonia Localized dystoniaLocalized dystonia

Torticollis (painful neck spasm)Torticollis (painful neck spasm) Scoliosis (abnormal curvature of the spine)Scoliosis (abnormal curvature of the spine)

Generalized dystoniaGeneralized dystonia Parkinson diseaseParkinson disease StrokeStroke

Also feature of schizophrenia or side effect of Also feature of schizophrenia or side effect of antipsychotic drugsantipsychotic drugs

ManagementManagement

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Page 88: Neurology

Parkinson DiseaseParkinson Disease Degeneration or damage to nerve cells within basal Degeneration or damage to nerve cells within basal

ganglia in brainganglia in brain

Leading neurologic disability in persons over 60 yoLeading neurologic disability in persons over 60 yo

Characterized by :Characterized by : Muscle rigidityMuscle rigidity Tremors (start on one side)Tremors (start on one side) WeaknessWeakness Shuffling gaitShuffling gait May lead to dementiaMay lead to dementia

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Page 89: Neurology

Central Pain SyndromeCentral Pain Syndrome Infection or disease of trigeminal nerve (cranial nerve Infection or disease of trigeminal nerve (cranial nerve

V)V) Tic douloureux (trigeminal neuralgia)Tic douloureux (trigeminal neuralgia)

• Common form Common form • Excruciating painExcruciating pain

Affects one side of faceAffects one side of face

Brief attacks of intense painBrief attacks of intense pain

May be associated with MS in persons under 50 yoMay be associated with MS in persons under 50 yo

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Page 90: Neurology

Bell’s Palsy (Facial Palsy) Bell’s Palsy (Facial Palsy) Paralysis of facial musclesParalysis of facial muscles

Inflammation of seventh cranial nerveInflammation of seventh cranial nerve Usually one sided and temporaryUsually one sided and temporary Often develops suddenlyOften develops suddenly

Affects 1 in 60 or 70 peopleAffects 1 in 60 or 70 people

Often spontaneous recoveryOften spontaneous recovery

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Page 91: Neurology

Bell’s Palsy Bell’s Palsy

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Page 92: Neurology

Amyotrophic Lateral Sclerosis (ALS)Amyotrophic Lateral Sclerosis (ALS) Lou Gehrig’s diseaseLou Gehrig’s disease

Rare disorders (motor neuron disease)Rare disorders (motor neuron disease)

Nerves that control muscular activity degenerate within Nerves that control muscular activity degenerate within brain and spinal cordbrain and spinal cord

Often begins with weakness in the arms and handsOften begins with weakness in the arms and hands

Paralysis progresses to include respiratory musclesParalysis progresses to include respiratory muscles

Death often within 2-4 years of diagnosisDeath often within 2-4 years of diagnosis

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Page 93: Neurology

Peripheral NeuropathyPeripheral Neuropathy Diseases and disorders affecting peripheral nervous Diseases and disorders affecting peripheral nervous

system, including:system, including: Spinal nerve rootsSpinal nerve roots Cranial nervesCranial nerves Peripheral nervesPeripheral nerves

Damage or irritation of axons or myelin sheathsDamage or irritation of axons or myelin sheaths

Affect different areas of bodyAffect different areas of body

Many medical causesMany medical causes

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Page 94: Neurology

MyoclonusMyoclonus Rapid and uncontrollable muscular Rapid and uncontrollable muscular

contractions (jerking) or spasms of muscle(s)contractions (jerking) or spasms of muscle(s) Occur at rest or with movementOccur at rest or with movement

Associated with:Associated with: Disease of nerves and musclesDisease of nerves and muscles Brain disorder (e.g., encephalitis)Brain disorder (e.g., encephalitis) Seizure disorderSeizure disorder

May occur in healthy personsMay occur in healthy persons

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Page 95: Neurology

Spina BifidaSpina Bifida Congenital defectCongenital defect

One or more vertebrae fail to develop completelyOne or more vertebrae fail to develop completely Leaves portion of spinal cord exposedLeaves portion of spinal cord exposed

Most common in lower backMost common in lower back

Incidence Incidence Morbidity/mortalityMorbidity/mortality

Cause is unknownCause is unknown

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Types of Spina BifidaTypes of Spina Bifida Severity depends on how much nerve tissue Severity depends on how much nerve tissue

is exposed after neural tube closureis exposed after neural tube closure Spina bifida occultSpina bifida occult MeningoceleMeningocele MyeloceleMyelocele EncephaloceleEncephalocele

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Polio (Poliomyelitis)Polio (Poliomyelitis) Caused by Caused by poliovirus hominispoliovirus hominis

Incidence declined in 1950s after vaccineIncidence declined in 1950s after vaccine

Risk if unvaccinated and traveling abroadRisk if unvaccinated and traveling abroad

Febrile illness with or without paralysisFebrile illness with or without paralysis

Can cause breathing difficultyCan cause breathing difficulty

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