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MDPH/OEMS Stroke Point of Entry. Created by: Central Mass EMS Corp. www.cmemsc.org Edited by: Lee H. Schwamm, MD, FAHA Associate Director, Acute Stroke Services, MGH www.stopstroke.org and Jonathan L. Burstein, MD, FACEP Medical Director, Office of Emergency Medical Services. Purpose.
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MDPH/OEMSStroke Point of Entry Created by: Central Mass EMS Corp. www.cmemsc.org Edited by: Lee H. Schwamm, MD, FAHA Associate Director, Acute Stroke Services, MGH www.stopstroke.org and Jonathan L. Burstein, MD, FACEP Medical Director, Office of Emergency Medical Services
Purpose To provide EMTs with the fundamental knowledge needed to recognize and manage potential stroke in the pre-hospital setting and make appropriate transport and hospital notification decisions based on the Stroke POE Plan. Courtesy of UMass Memorial LifeFlight & Mark Ide
Objectives • Identify the two major categories of stroke • List common signs & symptoms of stroke • Provide several risk factors for stroke • Explain the importance of rapid stroke therapy • Describe pre-hospital assessment and care, including the MASS and thrombolytic checklist • Describe the MA and Regional Stroke POE plan • Discuss appropriate treatment and transport modalities • Describe detailed stroke documentation
Background • Third leading cause of death in the U.S. • Approx. 700,000 people suffer strokes each year • Incidence increases with age • Mortality from stroke increases with age • Frequent cause of disability • Pre-hospital care has been primarily supportive
Stroke: What is it? • Injury or death of brain tissue due to oxygen deprivation; usually due to an interruption of blood flow • Also referred to as “Brain Attack” or “Cerebrovascular Accident” (CVA) • A true emergency!
Etiology Overview Atheromatous Atheromatous Source: Brady CD, Paramedic Care: Principles & Practice Vol.3 ©2001
Ischemic Stroke • About 80% of all strokes • Occurs when a cerebral artery is blocked by a clot or other foreign matter • Causes ischemia (inadequate blood supply to tissue) • Progresses to infarction (death of tissues) • Classified as: • Embolic Stroke • Thrombotic Stroke
Ischemic Stroke • Embolic • The occlusion is caused by an embolus (solid, liquid, or gaseous mass) carried to a blood vessel from another area • Most common emboli are blood clots • Risk factors for blood clots include Atrial Fibrillation and diseased or damaged carotid or vertebral arteries • Rare causes of emboli include air, tumor tissue, and fat • Occurs suddenly & may rarely be accompanied by headache
Embolic Stroke Source: http://www.irishhealth.com/?level=4&con=8
Ischemic Strokes • Thrombotic • The occlusion is caused by a cerebral thrombus; a blood clot which develops gradually in a previously diseased artery and obstructs it • Caused by atherosclerosis: • atheromatous plaque deposits form on the inner walls of arteries, resulting in narrowing and reduction of blood flow • platelets adhere to the roughened surface of the plaque deposit and a blood clot is created
Ischemic Strokes • Thrombotic, continued: • Signs & symptoms may develop more gradually • Often occurs at night with patient awakening from sleep with symptoms
Thrombotic Stroke Source: http://www.strokecenter.org/pat/ais.htm
Hemorrhagic Strokes • About 20% of all strokes • Onset usually sudden with severe headache • Classified as: • Intracerebral hemorrhage (within the brain) • Subarachnoid hemorrhage (in the fluid filled spaces around the blood vessels outside the brain)
Hemorrhagic Strokes • Intracerebral hemorrhage • Most occur in the hypertensive patient when a small vessel within the brain tissue ruptures • Hemorrhage inside the brain often tears and separates brain tissue
Intracerebral Hemorrhage Often caused by a ruptured blood vessel within the brain tissue of the hypertensive patient.
Hemorrhagic Strokes • Subarachnoid hemorrhage • Most often result from congenital blood vessel abnormalities (e.g., aneurysm) or head trauma
Subarachnoid Hemorrhage Often result from congenital abnormalities (e.g., aneurysms) or from head trauma Source: http://medic.med.uth.tmc.edu/edprog/Path/NeuroIIb.htm
Cerebral Aneurysm • dilation, bulging or ballooning out of part of the wall of a vein or artery in the brain.
Hemorrhagic Strokes • Subarachnoid hemorrhage • Blood in the subarachnoid space may impair drainage of cerebrospinal fluid and cause a rise in intracranial pressure • Herniation of brain tissue may occur
Herniation Protrusion of brain tissue through the base of skull (shown as “e”) from pressure due to mass lesion Source: http://www.uth.tmc.edu/radiology/test/er_primer/skull_brain/skull.html
What can be done? • Rapid recognition and prompt transport to a Primary Stroke Service (PSS) provider • A Primary Stroke service provider is a MDPH designated facility that offers emergency diagnostic and therapeutic services provided by a multidisciplinary team and available 24 hours per day, 7 days per week to patients presenting with symptoms of acute stroke.
Stroke: What can be done? Tissue plasminogen activator (tPA) and other thrombolytic (clot dissolving) agents used for heart attack, are also effective against certain ISCHEMIC strokes
Stroke: What can be done? A multi-center, randomized clinical trial conducted by The National Institute of Neurological Disorders and Stroke (NINDS) found that selected stroke patients who received t-PA within three hours of the onset of stroke symptoms were at least 30 percent more likely than placebo patients to recover from their stroke with little or no disability after three months.
Time Sensitive Treatment • Must receive treatment within three (3) hours of onset of symptoms • EMS must determine the exact time of onset as accurately as possible and also note the time the patient was last seen well • Transport to PSC within 2 hours of symptom onset if possible • Time = Brain Tissue
Team Approach • Detection • Importance of early recognition by lay public • Dispatch (9-1-1) • Obtains pertinent info; identifies urgency • Delivery (EMS) • Evaluates, obtains symptom onset, minimizes on scene time; immediate transport and pre-notification to PSS as soon as possible!
Team Approach • Door (Primary Stroke Service) • Alerts stroke team, performs patient exam & assessment, rapid CT scan • Data • Reviews all pertinent patient information • Decision • determines if thrombolytic therapy candidate • Drug • administers treatment <60 min of arrival
Therapies & New Developments • Thrombolytic Agents • Cytoprotective Agents • Platelet Inhibitor Drugs • Neuroradiological Intervention • Ultrasound-aided Therapy • In vitro diagnostic tests • may allow rapid detection of ischemic stroke in the field, at the bedside or in the ED!
Stroke Risk Factors • High blood pressure • Atrial fibrillation, CHF • High cholesterol • Diabetes (twice the risk) • Smoking (50% higher risk) • Alcohol or Drug Abuse • Inactivity or Obesity • Clotting problems (OCP, Sickle Cell)
Stroke Risk Factors, continued • Prior Stroke History • Heredity • Age (risk increases with age) • Gender • more common in men • more women die from stroke • Race (greater risk among African Americans)
Stroke: Signs & Symptoms • Paralysis on one side • Facial Droop • Limb Weakness • Paresthesias/Sensory loss (numbness or tingling) • Ataxia • Gait Disturbance • Uncoordinated fine motor movements
Signs & Symptoms, continued • Speech Disturbance • Vision Problems • Headache • Confusion/Agitation • Dizziness/Vertigo
Speech Disturbance • Aphasia • Inability to speak • Dysphasia • Difficulty speaking • Dysarthria • Impairment of the tongue muscles essential to speech
Vision Problems • Nystagmus • Involuntary jerking of the eyes • Diplopia • Double vision • Monocular blindness • Blindness in one eye
Transient Ischemic Attacks (TIAs) • Temporary interruption of blood supply to brain • Carotid artery disease a common cause • Stroke-like neurological deficit symptoms • abrupt onset • Symptoms resolve in less than 24 hours, usually within minutes. • No long-term effects, but high stroke risk
TIAs, continued • One third of TIA patients will suffer an acute stroke • Evaluate through history taking: • History of HTN, prior stroke, or TIA • Symptoms and their progression • Impossible (at this time) in pre-hospital setting to determine if a neurological event is due to TIA or stroke
Conditions that mimic Stroke • Hypoglycemia • Electrolyte imbalances (esp. Sodium) • Epidural or subdural hematoma • Brain abscess or tumor • Post-seizure • Migraine
Pre-hospital Care • Scene safety & BSI • Maintain airway & assist ventilations as indicated (do not hyperventilate) • Provide 2 lpm O2 NC unless in resp. distress • Provide C-Spine immobilization if indicated • Obtain Vital Signs & SAMPLE history • Collect or document ALL medications
Pre-hospital Care, continued • Record onset time and phone access to witness • Do not allow patient to exert themselves • Do not administer aspirin unless evidence of acute coronary syndrome • Complete and then document results of Massachusetts Stroke Scale (MASS) • (Refer to Protocols Appendix Q) • ONE positive finding is strongly predictive of stroke
Massachusetts Stroke Scale (MASS) • FACIAL DROOP • Patient shows teeth or smiles NORMAL ABNORMAL
MASS Scale • ARM DRIFT • Patient closes eyes & extends arms for 10 seconds NORMAL ABNORMAL
MASS Scale • SPEECH • Patient repeats “The sky is blue in Boston” Normal: States correctly without slurring on first attempt Abnormal: Slurs words, says the wrong words or is unable to speak on first attempt (mute)
Pre-hospital Care, continued • Determine blood glucose level if allowed; get medical control permission to administer glucose even if glucose level is low • If unconscious or seizing, transport on left side • If BP drops below 100 systolic, treat for shock • Initiate transport by ground to nearby PSS using BLS or ALS; activate ALS in patients with respiratory or hemodynamic compromise
Pre-hospital Care, continued • Notify receiving facility ASAP • Monitor/record VS every 5 minutes if unstable, or every 15 minutes if stable • Position the patient, protecting paralyzed extremities • Secure patient to stretcher and transport rapidly without excessive movement or noise • Use Thrombolytic Checklist en-route & include information in documentation
Pre-hospital Care: ALS • Contact medical control prior to administration of D50 or D5W • IV access & 12 lead should not delay transport
Stroke POE Plan • EMS Operational Definition of Acute Stroke • Onset of symptoms < 2hr duration (or since last seen at baseline) according to the MASS scale OR other concerning neurologic signs consistent with stroke, such as: • Eye movement abnormalities • Weakness affecting the leg • Double vision • Sudden onset dizziness AND unable to walk
Stroke POE Plan • Following the Mass EMS Pre-hospital Treatment Protocols for Acute Stroke (3.11), determine possibility of stroke based on MASS scale (Protocols, Appendix Q) and assessment • Establish time of onset and last time seen at baseline
Stroke POE Plan • If stroke symptoms present & time from onset of symptoms to hospital arrival will be < 2 hours, transport patient to nearest appropriate DPH designated provider of Primary Stroke Service (PSS) • Notify receiving facility ASAP
Stroke POE Plan • GOAL: To transport patient to PSS within 2 hours of symptom onset. • Choose most appropriate mode of transport (ground, air) and destination to achieve this.
Stroke POE Plan • It may be more appropriate to transport to the nearest hospital for acute stabilization if: • Compromised airway • Hemodynamically unstable • Depressed level of consciousness • Documented or suspected severe hypoglycemia (diaphoretic & known diabetic)
Stroke POE Plan • If CT Scan capability is unavailable at the nearest PSS (e.g., “Cautionary Status”), the patient should be transported to the next nearest appropriate PSS • If the patient will arrive at the PSS more than 2 hours after symptom onset, transport to the nearest hospital. • These time guidelines may be revised as new therapies extend the stroke treatment time frame