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Stroke Continuing Education EMS Region 7 May 2010. MENINGES. Dura Mater Arachnoid Pia Mater. Dura Mater creates Potential Space * Epidural space * Subdural space. Epidural Hemorrhage. Subdural Hemorrhage. CEREBRAL CORTEX. FRONTAL LOBE. Personality Behavior
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Stroke Continuing Education EMS Region 7 May 2010
MENINGES • Dura Mater • Arachnoid • Pia Mater
Dura Mater creates Potential Space * Epidural space * Subdural space Epidural Hemorrhage Subdural Hemorrhage
FRONTAL LOBE • Personality • Behavior • Voluntary motor function • Motor speech (Broca’s), Left side dominent • Intellectual functions, problem solving • Judgment; good/bad, right/wrong Called the “MOM” portion of the Brain
PARIETAL LOBE • Primary sensory lobe; pain, pressure, vibration, touch • Localization of stimuli • Object recognition • Position sense • Sensory association
TEMPORAL LOBE • Primary auditory lobe • Long term memory • Emotions • Cognitive speech (Wernicke’s); organize language, understand and respond to verbal input • Uncus discriminates smells
OCCIPITAL LOBE • Processing visual input
INTRACRANIAL DYNAMICS • Three substances in the cranial vault • Brain 80% • Blood 12% • CSF 8% MONRO-KELLIE DOCTRINE If one of these substances increase, then one or both of the other must therefore decrease to maintain normal pressure within the cranial vault
The Brain: Needs constant supply of O2 and glucose Receives 15% of cardiac output Consumes 20% of inspired O2 Perfused by the Circle of Willis BLOOD SUPPLY
Not that Willis….. THE CIRCLE OF WILLIS !
The brain’s own arterial circulatory system Connected to the aorta by the carotid arteries THE CIRCLE OF WILLIS
Stroke is no accident! • CVA is now called Stroke or “Brain Attack” • Carries the same urgency as AMI
STROKE DEFINED • Sudden, catastrophic event causing focal neuro impairment due to interruption of cerebral blood flow • Most often caused by an occlusion or rupture of an artery that supplies a specific part of the brain
Caused by anything that decreases blood flow to the brain Thrombus /embolus (A-fib, hypercoagulable state, etc) Carotid artery plaques Vasospasm Hypotension with carotid artery stenosis BRAIN ATTACK / ISCHEMIC STROKE
Ischemia • Can result from: • Vascular injuries • Secondary vascular spasm • Increased intracranial pressure • Focal or more global infarcts can result
Internal Carotid Artery occlusion No characteristic clinical picture May range from a TIA to infarction of a major portion of the ipsilateral (on the same side) hemisphere If adequate intracranial collateral circulation is present, may see no signs or symptoms Neurological symptoms may include: monoparesis to hemiparesis with or without a defect in vision impairment of speech or language transient monocular blindness
Middle Cerebral Artery occlusion Most occlusions in the first portion of this artery are due to emboli and typically produce a neurological deficit Opportunity for collateral circulation is restricted Neurological symptoms: hemiplegia (paralysis of one side of the body) hemisensory deficit hemianopsia (blindness in 1/2 of the visual field) aphasia (if infarct is in the dominant hemisphere)
Anterior Cerebral Artery occlusion Neurological symptoms may include: weakness of the opposite leg with or without sensory involvement apraxia (particularly of gait) possible cognitive impairment
Vertebrobasilar system Neurological symptoms may include: severe vertigo, nausea, vomiting, dysphagia, ipsilateral cerebellar ataxia decreased pain and temperature loss of 2 point discrimination diplopia, visual field loss, gaze palsies
Posterior Cerebral Artery Occulusion Neurological symptoms may include: Alterations in LOC, delerium and coma possible hemisensory disturbances visual disturbances with possible blindness Visual agnosia-lack of recognition or understanding of visual objects or loss of color Amenesia Loss of motor function possible
STROKE STATISTICS • Stroke occurs every 40 seconds • 3rd leading cause of mortality • 143,00 deaths annually • Death due to stroke every 3-4 minutes • 4.8 million stroke survivors • Leading cause of serious long tern disability • Life time cost of an ischemic stroke is $140,000 • Strides in prevention are off set by aging population • 80% of strokes are preventable!!!
TIA STATISTICS • 200,000-500,000 Per Year • Prevalence increases with age • Half of those with TIA’s fail to report it • 15% of strokes are preceded by a TIA • Following TIA • 12% of patients experience a stroke within the next 30 days • 3-17% have a stroke within 90 days • 25% die with in 1 year
STROKE AWARENESS:SURVEY • 38% aware of 5 stroke signs and would call 911 • Stroke pts: • 55% able to identify 1 stroke warning sign! • 60% able to identify 1 stroke risk factor! • Huge public education need
EFFECT OF STROKE ON BRAIN CELLS Interrupted supply O2 and glucose causing anaerobic metabolism and increasing cellular waste (toxins) causing cell membrane dysfunction causing cellular swelling and pressure on the cells which causes cellular ischemia and death
STROKE RISK FACTORS: NON MODIFIABLE • Age • >55 risk doubles every decade • Gender • Male more common • Female higher death rate • Heredity • Relative with stroke increased risk • Prior stroke/TIA • 25-40% chance of stroke in 5 years • Prior MI • Race • Increased in Hispanic/Asian/Pacific Islander • African American 2x higher rate than whites
STROKE RISK FACTORS: MODIFIABLE • HTN • >140/90 • Most important risk factor • Most common cause of stroke • Increased risk 4-6 times • Improved treatment may be responsible for decreased stroke deaths • High Cholesterol • Clogs arteries • 107 million in US
STROKE RISK FACTORS: MODIFIABLE • Atrial Fibrillation • Pooling blood promotes clots • Increases risk by 6 times • 15% stroke patients have A-Fib • Diabetes • Most have other risk factors as well • 2/3 die from stroke or heart disease • Increases risk 2-4 times
STROKE RISK FACTORS: MODIFIABLE • Tobacco • Damages vessel walls • Accelerates arterial stenosis • Increases CV workload • Increases BP • Increasing clotting factors • Doubles risk • Alcohol • Heavy use related to stroke • >2/day may increase risk by 50% • Leads to HTN
STROKE RISK FACTORS: MODIFIABLE • Obesity • Strains entire cardiovascular system • Likely to have DM, HTN and high cholesterol
NEURO ASSESSEMENT BASELINE ASSESSMENT IS OF GREAT IMPORTANCE TO DETERMINE THE HISTORY OF THE PRESENT ILLNESS AND TO ACT AS A GUIDE FOR FURTHER SERIAL ASSESSMENTS
ASSESSMENT: SYMPTOMS/CHIEF COMPLAINT • Headache of unknown cause • AMS/Sudden confusion • Photophobia, visual deficits • Stiff neck • Weakness/paralysis • Sensory loss face, arm or leg • Vertigo, dizziness,syncope,ataxia • Trouble speaking or understanding • Seizure
ASSESSMENT: CINCINNATI STROKE SCALE • 3 Components • Facial (Smile) • Arm drift-Unilateral weakness • Speech- abnormal speech pattern • Takes less than 1 minute • Reliability • 1 finding= 72% • 3 findings = 85% • However, patients can be having a stroke despite a normal CSS • Correct documentation
CSS: ARM DRIFT • Weakness • Clumsiness • Heaviness • Documentation – in narrative or use built-in Zoll categories • Normal • Drift • Can’t resist gravity • No effort • No movement
CSS: SPEECH • Speech • Ask the patient to repeat a simple sentence • The sky is blue • You can’t teach an old dog new tricks • Assess • Ability to form words • Abnormal pattern • Articulation • Hoarseness • Phonation • Rate
CCS: SMILE • Facial Symmetry • Smile/Grimace • Show teeth • Does he have a deficit?
BELL’S PALSY vs. STROKE • Bell’s Palsy • Total hemiparesis of face • Stroke • Can wrinkle both sides of forehead but has lower facial weakness
STROKE: ABNORMAL PRESENTATIONS • Weakness • Quick neuro exam • Negative suspect ACS obtain a 12 lead • Positive Consider Stroke • Syncope • Hx of seizures • Exam • GCS • ECG • Trauma
STROKE: ABNORMAL PRESENTATIONS • AMS • Scene size up • Differential diagnosis • AEIOUTIPS • Other • Visual disturbances • Hoarseness • “Heavy” sensation • Cranial nerve S/S
STROKE: ABNORMAL PRESENTATIONS • Strong trend for misdiagnosis <35 • 50% of those were diagnosed as inner ear disorder • Women • AMS (most common) • Meaning confusion • Disorientation • Loss of consciousness • Delays in triage, exam and imaging
IT’S NEURO TIME!! • Lessons learned in Trauma and Cardiac care can be applied to Stroke care: • Patients need definitive treatment in the hospital • Outcomes greatly improved with early access to emergency care
STROKE CHAIN OF SURVIVAL • Goal • Minimize brain injury and maximize recovery • Rapid • Recognition and reaction • EMS Dispatch • EMS transport and pre arrival notification • Diagnosis and treatment
7 D’s OF STROKE CAREPOTENTIAL POINTS OF DELAY • Detection • Dispatch • Delivery with advance notification • Door • Data • Decision • Drug/Monitoring
EMS PREHOSPITAL STROKE CARE • ID stroke symptoms • Transport to a Stroke Center • Medical Center pre arrival notification • Safest most efficient method of transport • Manage the life threats • Perform targeted neuro assessment • ID/treat other causes of symptoms • Establish time of symptom onset