neurological disorders

• Neurologic System


  Function: Control of all functions and behavior in the human body
• Neuron


  The basic unit
• Parts of a neuron

  • Dendrites - branch like recipients of electrochemical impulses
  • Axons - long projections carrying electrochemical impulses away from the body of the neuron
  • Cell body/Soma
  • Nucleus
  • Synaptic bulb - site of communication between neuron and target cell/organ
  • Neurolemma - specific to the peripheral nervous system; aids the regeneration of the myelin sheath responsible for the conduction of the nerve impulses
  • Node of Ranvier - spaces between the neurolemma
  • Neuroglial cell - supports, protect, and nourish neurons
• Neurotransmitters


  Chemicals transported within neurons or between neurons and specific tissues/ organs that may excite, inhibit, or modulate specific actions
• Neurotransmitters and their actions

  • Acetylcholine - E/I, Parasympathetic system/arousal/involuntary movement
  • Serotonin - I, Mood, sleep, Pain pathways, happiness
  • Dopamine - I, Behavior, fine motor movement, motivation
  • Norepinephrine - E, Mood, overall activity, stress
  • Gamma-aminobutyric acid (GABA) - I, Calming effect/ Inhibitor of another neurotransmitter/s
  • Enkephalin, Endorphin - E, Pleasurable sensation, pain transmission, lowers stress
• Parts of the Brain and their functions

  • Cerebrum - Frontal lobe: Concentration, abstract thought, memory, motor function, speech, affect, judgment, personality, inhibitions
  • Parietal lobe: Sensory analysis and interpretation, spatial awareness, size and shape discrimination
  • Temporal lobe: Auditory reception and memory, language and music comprehension
  • Occipital lobe: Visual interpretation and memory
  • Corpus Callosum: Connects both hemispheres of the brain for information transmission
  • Basal Ganglia: Fine motor movement
  • Thalamus: Relay station of all sensation except smell
  • Hypothalamus: Regulates the pituitary secretion of hormones
• Parts of the Brain Stem and their functions

  • Midbrain: Connects the pons and cerebellum, with the medulla oblongata; center of auditory and visual reflexes
  • Pons: Bridges the halves of the cerebellum and the medulla and midbrain; respiration
  • Medulla: Decussation of motor and sensory fibers; reflex center for vital functions (VS, coughing, sneezing, swallowing, vomiting)
  • Reticular Formation: Arousal and sleep-wake cycle
• Protective Structures of the Brain

  • Skull: Rigid bone structure to protect from injury
  • Meninges: Protect, support, and nourish the brain and spinal cord
  • Dura Mater: Outermost layer; tough, thick, inelastic, fibrous
  • Arachnoid Mater: Middle layer; extremely thin, delicate; spider-web like
  • Pia Mater: Innermost; thin, transparent; hugs every fold of brain's surface
• Cerebrospinal Fluid


  Clear, colorless fluid that nourishes, transports wastes, and cushions the brain; produced at choroid plexus at 500ml/day
• Cerebral Circulation


  • Arterial and venous systems are not parallel
  • Brain has collateral circulation through the Circle of Willis
  • Blood vessels have two layers only
• Spinal Cord


  • Anterior/Motor Root: voluntary and reflex activity of innervated muscles
  • Posterior/Sensory root
  • Lateral horn: autonomic fibers
• Cranial Nerves


  • I Olfactory - Smell
  • II Optic - Vision
  • III Oculomotor - EOM (inferior rectus and medial rectus, PERRLA
  • IV Trochlear - EOM downward to middle
  • V Trigeminal - Facial sensation, corneal reflex, mastication
  • VI Abducens - EOM away from middle
  • VII Facial - Facial Ex., Salivation, taste, ear sen.
  • VIII Vestibulocochlear /Auditory - Hearing Equilibrium
  • IX Glossopharyngeal - Taste, Swallowing, tongue movement
  • X Vagus - Innervation of thoracic and abd. Org.
  • XI Spinal Accessory - Sternocleidomastoid
  • XII Hypoglossal - Tongue movement
• Spinal Nerves


  • 8 pairs cervical
  • 12 pairs thoracic
  • 5 pairs lumbar
  • 5 pairs sacral
  • 1 pair coccygeal
  • Dorsal - Afferent, Sensory
  • Ventral - Efferent, Motor
• Autonomic Nervous System


  • Internal organ activity regulation/homeostasis and maintenance
  • Sympathetic (excitatory/ fight or flight) vs. parasympathetic (inhibitory/ rest and digest)
• Autonomic Nervous System Actions

  • Pupils: Dilatation (Sympathetic), Constriction (Parasympathetic)
  • Cardiovascular: Inc. HR, BP, force of contraction; constriction of bloob vessels to vital organs, dilation of blood vessels to skeletal and heart muscle (Sympathetic), Dec. BP, HR, force of contraction; constriction of heart muscle (Parasympathetic)
  • Respiratory: Bronchodilation; inc. RR (Sympathetic), Bronchoconstriction; dec. RR (Parasympathetic)
  • Digestive: Liver - Glycolysis (sugar breakdown) (Sympathetic), Glyconeogenesis (sugar formation) (Parasympathetic), Peristalsis - decrease (Sympathetic), increase (Parasympathetic), Muscular Sphincters in GIT - contracted (Sympathetic), relaxed (Parasympathetic), Saliva secretion - Thick, viscous (Sympathetic), Thin, watery (Parasympathetic), Gastro-int secretion - increase (Parasympathetic)
  • Genitourinary: Urinary bladder - Relaxed (Sympathetic), Contracted (Parasympathetic), Urinary sphincter - Contracted (Sympathetic), Relaxed (Parasympathetic), Uterine wall - Contracted (Sympathetic), Relaxed (Parasympathetic), Penile erection - (Parasympathetic)
  • Skin: Perspiration - Increase (Sympathetic)
• Health History


  Common symptoms: Pain (acute/chronic), Seizures, Dizziness (abnormal sensation of imbalance/ movement) and vertigo (illusion of movement, usually rotation), Visual disturbances, Muscle weakness, Abnormal sensation
• Physical Assessment


  • Consciousness and cognition, Mental status, Intellectual functioning, Thought content, Emotional status, Language ability, Impact on lifestyle, LOC
  • Cranial nerves
  • Motor system - Motor ability, Balance and coordination
  • Sensory system - Tactile sensation, Pain and temperature, Vibration
  • Reflexes
  • Patterns of respiration
• Glasgow Coma Scale


  Assesses level of consciousness
• Alterations in LOC


  Change in a patient's state of awareness (ability to relate to self and the environment) and arousal (alertness) - ranging from a state of unconsciousness to hyperarousal
• Modified Ashworth Scale (MAS)


  Assesses muscle tone
• Rating Scale for Muscle Strength


  Assesses muscle strength
• Reflexes


  Assess neurological function
• Positron Emission Tomography (PET)


  Diagnostic test that shows metabolic changes, biochemical alterations and blood flow, locates and differentiates lesions
• Cerebral Angiography


  Diagnostic test to visualize blood vessels in the brain
• Electroencephalography


  Diagnostic test to measure electrical activity in the brain
• Electromyography


  Diagnostic test to measure electrical activity in muscles
• Lumbar puncture and CSF examination


  Diagnostic test to collect and analyze cerebrospinal fluid
• Altered LOC


  Change in a patient's state of awareness (ability to relate to self and the environment) and arousal (alertness) - ranging from a state of unconsciousness to hyperarousal
• Pathophysiology of Altered LOC

  Varied, depending on cause. May be neurologic, toxicologic, or metabolic
• Assessment of Altered LOC

  • Initial: subtle behavioral changes
  • Decreasing state of alertness and consciousness; orientation
  • Changes in pupillary response, eye opening response, verbal response, and motor response
  • Periorbital edema
  • Pattern of respiration
  • Eyes: pupil reactivity, equality, and reaction to light; corneal reflex
  • Facial symmetry
  • Nuchal rigidity
  • Response to noxious stimuli
  • Deep tendon reflex
  • Pathological reflex
  • Abnormal posturing
• Medical Management of Altered LOC

  • Maintain airway patency
  • Mechanical ventilation until independent breathing ability is established
  • Intubation or tracheostomy
  • Monitor circulatory status
  • IV catheterization
  • Adequate cardiac and cerebral perfusion
  • Neurologic support, depending on deficits
  • Nutritional support - NGT insertion or through gastrostomy
• Nursing Management of Altered LOC

  • Consider ALL complications related to immobility
  • Maintain airway patency
  • Elevate head of bed to 30 deg. to prevent aspiration
  • Position patient to lateral or semi-prone position to promote drainage of secretions and to prevent the tongue from falling backward, obstructing airway
  • Suction and practice oral hygiene
  • Perform chest physiotherapy and postural drainage
  • Provide oral care
  • Perform oral care carefully, preferably every 8hrs
  • If with ETT, shift the tube to the opposite side of the mouth once daily
  • Prepare and follow turning schedules
  • Reduce shearing forces when turning the patient
  • Perform passive ROM exercise
  • Position the body correctly
  • Clean eyes with CB with sterile saline solution
  • Instill artificial tears every 2hrs
  • Control body temp by practicing fever reducing strategies to reduce metabolic demands of the body
  • Perform urinary catheterization
  • If conscious, initiate bladder training
  • Provide stool softeners as prescribed to prevent inc. ICP
  • Administer enema as ordered
  • Assist in achieving family needs
  • Monitor for possible complications
• Increased Intracranial Pressure (ICP)


  A rise in the pressure inside the skull that can result from or cause brain injury
• Monro-Kellie Hypothesis


  The sum of volumes of brain, cerebrospinal fluid (CSF) and intracerebral blood is constant. An increase in one should cause a reciprocal decrease in either one or both of the remaining two.
• Pathophysiology of Increased ICP

  • Increase volume of any intracranial contents (blood, CSF, brain matter)
  • Increased ICP
  • Decreased cerebral perfusion
  • Cell death/ necrosis, increases CO2
  • Cerebral edema <_ vasodilation
• Assessment of Increased ICP

  • Earliest sign: Change in LOC
  • Abn. Pupillary, respiratory and vasomotor response
  • Abn motor response: decorticate, decerebrate, flaccid
  • Cushing's triad: HYPERTENSION, BRADYCARDIA, BRADYPNEA
  • Herniation, diabetes insipidus, SIADH
• Medical Management of Increased ICP

  • CT scan, MRI
  • Invasive ICP monitoring
  • Osmotic diuretics (Mannitol)
  • Cerebral perfusion maintenance (inotropes)
  • Fluid restrictions
  • CSF draining
  • Fever control
  • Circulatory stability and respiratory maintenance
  • Reduction of metabolic demands
• Nursing Management of Increased ICP

  • Maintain airway patency
  • Avoid coughing
  • Achieve adequate breathing pattern
  • Maintain adequate cerebral perfusion
  • Position head in midline, elevated at 30-45 deg unless contraindicated
  • Avoid extreme neck rotation and flexion
  • Avoid Valsalva maneuver and abdominal distention; use stool softeners as prescribed.
  • If alert and able to eat, provide high-fiber diet
  • Avoid high PEEP when patient is on mech vent to promote venous drainage on upper body
  • Space interventions that will allow adequate patient rest
  • Provide a calm atmosphere; reduce environmental stimuli.
• Meningitis


  An inflammation of the lining around the brain and spinal cord caused by bacteria (Streptococcus pneumonia, Neisseria meningitides and Haemophilus influenza) or viruses (secondary to lymphoma, leukemia, or HIV).
• Multiple Sclerosis


  An immune-mediated, progressive demyelinating disease of the CNS, Typically manifest in young adults ages 20-40 years, More frequent in women than men.