Chapter 31 Stroke

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 2 Overview  Pathophysiology  Types of Stroke  Risk Factors  Assessment  Management

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 3 Pathophysiology  Injury to brain tissue caused by disruption of blood flow  Also called a cerebrovascular accident (CVA)  Results in loss of body function

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 4 Pathophysiology  Advances in treatment  Time-sensitive condition

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 5 Types of Stroke  Brain cells depend on oxygen  Two types of stroke

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 6 Types of Stroke  Ischemic stroke –Blockage of blood supply –85% of strokes

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 7 Types of Stroke  Ischemic stroke –Blood vessels narrow –Platelets accumulate –Vessel is blocked

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 8

9 Types of Stroke  Ischemic stroke –Embolus can also form elsewhere and travel to the brain

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 10 Types of Stroke  Ischemic stroke –Severe shock can cause very low blood pressure –Brain receives no oxygen

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 11 Types of Stroke  Ischemic stroke –Brain cells deprived of oxygen will die in a very short time –A group of cells that have died is called an infarct –The tissue around an infarct is the penumbra –The penumbra may recover

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 12 Types of Stroke  Transient ischemic attack –Stroke symptoms that resolve spontaneously –Caused by a thrombus –High risk of a stroke

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 13 Types of Stroke  Hemorrhagic stroke –Caused by rupture of a blood vessel in brain –May be from high blood pressure or aneurysm –15% of strokes

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 14 Types of Stroke  Hemorrhagic stroke –Leaking blood can injure brain tissue –Intracranial pressure may become elevated

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 15

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 16 Risk Factors  Vascular disease  Diabetes  Irregular heart rhythms  High blood pressure  Previous stroke

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 17 Assessment  Signs and symptoms –Depend on the affected area of brain –Middle cerebral artery is most common vessel affected –Dysarthria

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 18 Assessment  Signs and symptoms –Headache and ICP –Early diagnosis improves outlook

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 19  Symptoms associated with stroke –Generalized or focal weakness –Paralysis on one side of the body –Paresthesias on one side of the body –Difficulty in speaking Assessment

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 20 Assessment  Symptoms associated with stroke –Headache –Vomiting –Visual changes –Dizziness

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 21 Assessment  Assess for life threats  History  Focused neurologic examination

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 22 Assessment  Initial assessment –Assess ABCs –Identify potential life threatening issues at that point

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 23 Assessment  Focused history –Past medical history –Allergies –Medications taken

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 24 Assessment  Focused history –Obtain history from family, if necessary –The management of stroke is very time sensitive

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 25 Assessment  Focused physical exam –Patient’s mental status –Pupils –Assess for pronator drift –Assess for facial droop –Assess for dysarthria

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 26 Assessment  Focused physical exam –Patient’s mental status –Assess pupils

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 27 Assessment  Focused physical exam –Pronator drift A useful way to test for arm weakness

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 28 Assessment  Focused physical exam –Facial droop Facial droop indicates facial muscle weakness

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 29 Assessment  Focused physical exam –Dysarthria Garbled speech

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© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 31 Assessment  Focused physical exam –Expressive aphasia –Receptive aphasia –No speech

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 32 Assessment  Focused physical exam –Cincinnati Prehospital Stroke Scale –Other stroke scales

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 33 Assessment  Baseline vital signs –May have high blood pressure

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 34 Management  Recognize and transport  Every minute counts

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 35 Management  Hospital management –Diagnosis –Therapy

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 36 Management  Hemorrhagic stroke –Control blood pressure  Ischemic stroke –Medications

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 37 Management  Stroke centers  Timely transport

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 38 Management  Specific management of all stroke patients includes: –ABCs –High-flow 100% oxygen –Support blood pressure –Elevate head of bed

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 39  Other diagnoses to consider in presence of stroke-like symptoms: –Hypoglycemia –Bell’s palsy –Traumatic brain injury Management

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 40 Management  Other diagnoses to consider in presence of stroke-like symptoms: –Seizure –Migraine –Drug toxicity

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 41  Transport –To most appropriate hospital –ALS intercept –Notify hospital Management

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 42 Management  Ongoing assessment –Note carefully any changes

© 2005 by Thomson Delmar Learning,a part of The Thomson Corporation. All Rights Reserved 43 Stop and Review  Describe the pathophysiology of ischemic stroke.  Describe the pathophysiology of hemorrhagic stroke.  Identify several conditions that might mimic stroke.