CH 18 NEURO

• Nervous System


  Splits in two: Central Nervous System (CNS) and Peripheral Nervous System
• Central Nervous System (CNS)


  • Brain and Spinal Cord (Connects brain to peripheral nervous system)
• Peripheral Nervous System


  • Carries messages to and from the CNS
• Three Major Parts of Brain

  • Brain Stem
  • Cerebellum
  • Cerebrum (largest part)
• Brain


  Controls: Speech, Breathing, and other body functions
• Brain Stem


  • Controls: Breathing, BP, Swallowing, Pupil Constriction
  • Contains Pons, Medulla Oblongata
• Cerebellum


  • Controls: Muscle and Body Coordination, involves coordinating tasks: balance, walking, writing, picking up coin, playing piano, daily things
• Cranial Nerves


  Msgs sent to and from the brain travel through nerves, 12 cranial nerves run directly from the brain to parts of the head such as eyes, ears, nose and face. Rest of the nerves in the spinal cord and exit brain through large opening in base of the skull called the foramen magnum.
• Spinal Nerves


  Each vertebra in the neck and back = 2 nerves branch out from the spinal cord and carry signals to and from the body
• Brain is sensitive to = O2, glucose, and temp levels: significant change in any of these levels will result neurologic change
• If the problem is caused by disorder in heart and lung

  Entire brain will be affected. (ex: hypoxia will affect the entire brain causing anxiety, restlessness, and confusion)
• If the problem is caused by brain, such as poor blood supply

  The pt may have s/s's affecting only one side of the body. Right side of brain = S/s on left side of body, Left side of brain = S/s on right side of body
• Brain and skull do not sense pain. Headache caused by: surrounding areas of the face, scalp, meninges, larger blood vessels, and the muscles of the head, neck, and face.
• Meninges


  • Three membranes that envelop the brain and spinal cord: Dura Mater, Arachnoid Mater, Pia Mater
• Cerebrospinal Fluid


  Located in the subarachnoid space between the arachnoid mater and the Pia mater
• Dura Mater


  Thick membrane made of dense irregular connective tissue that surrounds the brain and spinal cord (outermost membrane)
• Arachnoid Matter


  Middle layer, thin weblike, where cerebrospinal fluid is found
• Pia Mater


  Delicate, adheres directly to brain, very thin, fibrous, and vascular --> bleeds rapidly (innermost layer)
• Headache


  Most common complaint you will hear from pt. Should be considered serious condition and requires a complete assessment and transport to the hospital
• Kinds of Headaches


  • Tension Headaches
  • Migraines
  • Sinus Headache
• Tension Headaches


  Caused by stress - Caused by muscle contractions in the head, neck. Described as: squeezing, dull, or as an ache. Do not require medical attention.
• Migraines


  Thought to be caused by changes in blood vessel size in the base of the brain, described as: pounding, throbbing, pulsating - associated w/ nausea, vomiting, may be preceded w/ flashing lights or partial vision loss - can last several hours or days
• Sinus Headache


  Caused by pressured that results from accumulated fluid in the sinuses, can usually result from flu.
• Red flags for headaches

  • Sudden onset
  • Explosive/Thunderclap Pain
  • Altered Mental Status
  • > 50
  • Depressed immune system
  • Neurologic deficits
  • Neck stiffness/pain
  • Fever
  • Changes in vision
  • One-sided paralysis or weakness
• Stroke


  Also called cerebrovascular accident (CVA) - interruption of blood flow to an area within the brain that results in the loss of brain function
• Ischemic Stroke


  • Most common - caused by blockage of blood vessels due to clot
  • Results from thrombosis or embolus or atherosclerosis
• Thrombosis


  Formation of blood clot inside a blood vessel, obstruction from flow of blood through the circulatory system
• Embolus


  Blood clot, air bubble, piece of fatty deposit, or other object that has been carried in the bloodstream to lodge in a vessel and cause an embolism
• Atherosclerosis


  Artery narrowed by plague.. caused by high BP, high cholesterol, smoking, damage leads to formation of plague.. causes white blood cells to stream in and digest the LDL (low density lipoprotein) over years, cholesterol and cells become plaque in the walls of the artery
• Ischemic Stroke Symptoms


  Loss of movement on the side of the body opposite from the side where the blockage has occurred
• Ischemic Stroke Treatment


  Aims to remove blood clots through aspirin or TPA (Tissue plasminogen activator)
• Hemorrhagic Stroke


  • Occurs when blood vessel leaks or ruptures
  • Risk Factors: Uncontrolled High BP, Stress, Too many anti-coagulants
• Hemorrhagic Stroke BP


  Usually: over 140 systolic w/ stroke symptoms
• Aneurysm


  Aneurysm overstretched and rupture resulting from weakening of the arterial wall, blood spurts into area
• Berry Aneurysm


  Common cause of hemorrhagic strokes in healthy, young people, presents as worst headache of their life.. causes subarachnoid hemorrhage
• Subarachnoid Hemorrhage


  Bleeding within the area b/w the brain and the tissues that cover it
• Intra-cerebral Hemorrhage


  A life threatening type of stroke caused by bleeding into the brain tissue, high fatality rate
• Transient Ischemic Attack (TIA)

  • Causes stroke-like symptoms for only 24 or less hours
  • A small clot in a cerebral artery which presents as temporary symptoms
  • May be a warning sign of a larger stroke to come and is considered an emergency
  • About 1/3 of pts who have TIA will experience a stroke soon after
• Signs and Symptoms of Stroke

  • Facial Drooping
  • Sudden weakness/numbness in face, arm, leg, one side of body
  • Double vision or sudden vision in one eye
  • Lack of muscle coordination (ataxia) or loss of balance
  • Decreased or absent movement and sensation on one side of body
  • Difficulty swallowing
  • Decreased LOC or hyperaware
  • Speech disorders
  • Slurred speech (dysarthria)
  • Sudden severe headache
• Stroke in the Left Hemisphere

  • Causes aphasia (inability to produce or understand speech)
  • Ask: "What day is it?" and check for inappropriate words
  • Strokes that affect the left side of the brain can also cause paralysis to the right side of the body