PWCDFR

1
PWCDFR

• Protocol Review
• Stroke (CVA) 21

2
Scope

• 3rd leading cause of death
• Approximately 160,000 annually
• 500,000 new cases annually
• 100,000 recurrent strokes annually
• 1/3 of new stroke survivors will have a
  recurrent stroke within five years
• The incidence of stroke is highest for black
  males
• White males and females suffer strokes on an
  equal basis however, the death rate is much
  higher for females

3
The Cost Of Stroke

• 30 billion annually
• Direct costs 17 billion
• Indirect costs 13 billion annually
• Loss of productivity

4
Basic Anatomy

• The Central Nervous System
• Brain
• Spinal Cord
• The brain
• Cerebrum
• Diencephalon
• Cerebellum
• Brain stem

5
Cerebrum

• Largest portion of the brain
• Controls higher functions
• Thought
• Memory
• Voluntary movement
• Divided down the middle into hemispheres (right
  and left)
• Each hemisphere is divided into four lobes
• Frontal (anterior, superior)
• Temporal (lateral)
• Parietal (lateral, superior)
• Occipital (posterior)

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Diencephalon

• Area between cerebrum and brain stem
• Major Structures
• Thalamus
• Sensory perception
• Motor functions (movement)
• Hypothalamus
• Regulates hormones
• Regulates temperature
• Regulates pain
• Pituitary Gland
• Master gland of the endocrine system

7
Cerebellum

• Posterior portion of the brain
• Just inferior to the cerebrum
• Controls coordination

8
Brainstem

• Most inferior portion of the brain
• Connects to the spinal cord
• Major structures
• Midbrain
• Pons
• Medulla oblongata
• Major functions
• Control of vegetative functions
• Heart rate, breathing, digestion

9
The Linings Of The Brain(Meninges)

• Pia mater
• Thin and delicate membrane that adheres to the
  brain
• Arachnoid membrane
• Thin, transparent, middle membrane that resembles
  a spiders web
• Dura Mater
• Outer most membrane that is thick and fibrous

10
Cerebrospinal Fluid, The Brains Cushion

• Produced in the ventricles of the brain
• Bathes the brain and spinal cord
• 150 ml (adult)
• Circulates between the pia mater and arachnoid
  membrane
• High in dextrose
• Nutrients for the membranes
• Normally is crystal clear

11
The Cranial Vault, The Brains Protector And
Killer

• Relatively thick bones that are fused together to
  form one
• Temporal area is very thin
• Inferior portion of the brain is snugly fitted
• Little motion
• No room to expand
• Superior portion of brain is less tightly fitted
• Allows for some sloshing
• Owing to the cranial vaults rigidity and the
  compactness of the brain into the vault, outward
  swelling is extremely limited

12
The Brains Blood Supply

• 25 of cardiac output is circulated to the brain
• High O2 and glucose consumption
• 80 via the internal carotid arteries
• 20 via the vertebral arteries

13
Types Of Stokes

• Ischemic
• Thrombotic
• Embolic
• Hemorrhagic

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Ischemic Stroke/Thrombotic

• A loss of blood flow through a cerebral artery
  owing to thrombus formation
• Most commonly caused by atherosclerosis
• Tissue that the artery primarily serves dies
  within minutes
• Infarct area
• Tissue that surrounds infarct area is ischemic
  and is in danger of infarcting
• Ischemic penumbra
• Must be reperfused within 3 hours

15
Internal Carotid Thrombus
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Cerebral Infarction

• Here is a large remote cerebral infarction.
  Resolution of the infarction has left a huge
  cystic space encompassing much of the cerebral
  hemisphere in this neonate.

17
Ischemic Stroke/Embolic

• A blockage of a cerebral artery from a clot or
  other mass
• travels to the brain from some other part of the
  body
• Most commonly from the atria of the heart owing
  to atrial fibrillation
• The effects to the brain are the same as that of
  a thrombotic stroke

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CT OF Infarcted Areas Owing To An Embolic Stroke
Note the shift of the ventricle
19
Emboli On Surface Veins

• Hint, they look like dark bubbles

20

• This angiogram demonstrates an embolic
  obstruction of a branch of the left common
  carotid artery just past the first main
  bifurcation

21

• Here is a cerebral infarct from an arterial
  embolus, which often leads to a hemorrhagic
  appearance. There is edema which obscures the
  structures. The acutely edematous infarcted
  tissue may produce a mass effect. Note the
  decrease in size of the ventricle on the left
  with shift of the midline.

22
Hemorrhagic Stroke

• A disruption of blood flow to brain tissue owing
  to a ruptured blood vessel
• Tissue that surrounds the rupture does not
  necessarily lose all of its blood supply
• Escaping blood irritates brain tissue and leads
  to rises in intracranial pressures
• Carries a high mortality rate
• Hypertension is the most prevalent cause

23
Intraventricular and Intracerebral hemorrhage
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Cerebral Aneurysm

• This patient is at extreme risk for developing a
  hemorrhagic stroke

25
Ruptured Berry Aneurysm

• The white arrow on the black card marks the site
  of a ruptured berry aneurysm in the circle of
  Willis. This is a major cause for subarachnoid
  hemorrhage .

26
Vascular Malformation

• Another cause for hemorrhage, particularly in
  persons aged 10 to 30, is a vascular
  malformation.
• Seen here is a mass of irregular, tortuous
  vessels over the left posterior parietal region.

27

• Acute brain swelling in the closed cranial cavity
  is serious. Swelling of the left cerebral
  hemisphere has produced a shift with herniation
  of the uncus of the hippocampus through the
  tentorium, leading to the groove seen at the
  white arrow.

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Signs And Symptoms Of Ischemic Stroke

• Sudden weakness or paralysis of the face and leg
  on one side of the body
• Slurred speech
• Sudden confusion with difficulty speaking or
  understanding speech
• Sudden dimness or loss of vision
• particularly in one eye
• Loss of balance and coordination
• Sudden severe headache
• Abnormal sensations or loss of sensation in an
  arm or a leg or on one side of the body
• Note
• Thrombotic strokes tend to occur during periods
  of inactivity while embolic strokes tend to occur
  during periods of high activity

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Signs And Symptoms Of Hemorrhagic Stroke

• Symptoms of a hemorrhagic stroke are largely the
  same as those of an ischemic stroke but may also
  include
• Sudden severe headache
• Nausea and vomiting
• Seizures
• Temporary or persistent loss of consciousness
• Severe hypertension

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Late Signs Of Stroke

• Coma
• Cushings Triad
• Hypertension
• Bradycardia
• Slow and irregular respirations
• Fixed and Dilated pupil (s)

Note This pupil also has a cataract
31
The Protocol

• Perform initial patient assessment and obtain
  pertinent medical history
• Time of onset is crucial
• Use multiple sources and compare if possible
• Use references if necessary
• Meal, news program, football program, etc.
• How rapid S/S progressed
• Rule-out trauma
• Take C-spine precautions if indicated

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Consider Using The Cincinnati Stroke Test

• Have them
• Smile broadly, enough to show teeth
• This reveals facial numbness or drooping on one
  side
• Close their eyes, raise their arms in front and
  hold them out for a count of 10
• This reveals arm weakness
• Repeat a simple phrase, such as "How are you, I'm
  fine, thanks."
• This reveals slurring of speech

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Airway

• Establish and maintain a patent airway
• Administer O2
• Ventilate as required
• Note High arterial oxygen PO2 can lead to
  decreased cerebral blood flow. If SpaO2 is 90 or
  greater and ventilatory assistance is not
  required, low flow oxygen via a nasal cannula is
  preferred over a NRB
• Elevate the head of the semiconscious or
  unconscious patient 20 30 degrees
• Refer to Unconscious Protocol (22)

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Additional Things

• Obtain blood sugar level
• Hypoglycemia can mimic a stroke
• Complete Thrombolytic Checklist
• Cardiac Monitor
• Treat life-threatening dysrhythmias per
  appropriate sub-protocol
• Do not treat bradycardia unless patient is
  hypotensive
• Establish an IV of Normal Saline (KVO rate)
• Establish a second IV (same arm if possible) if
  time allows

35
Additional Things

• Complete the Thrombolytic Eligibility Checklist
• Contact the receiving hospital and initiate a
  CODE STROKE

36
Summary

• Stroke carries a high mortality and disability
  rate
• While EMS can do nothing to reverse the initial
  infarct area of all types of strokes, it can
  greatly influence the long term outcome of
  ischemic strokes
• Get the patient to a appropriate stroke
  facility within 3 hours of the onset of symptoms
• Our primary objectives are
• Recognition
• Supportive care
• Rapid transport