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  1. 1. Neurological Dysfunction Functions of the Nervous System * Consciousness and mentation * Movement: head and body * Sensation * Integrative regulation Nerve Cells * Neurons: highly specialized cells; basic unit of the nervous system; contains a sensory (afferent) and motor (efferent) component. * Neuroglia: connective tissue that connects nerve cells Three Components of the Nervous System * Central: brain and spinal cord * Peripheral: cranial and spinal nerves * Autonomic: sympathetic and parasympathetic Central Nervous System * Cerebrum: is the largest area; divided into four major lobes: * Frontal * Parietal * Temporal * Occipital Cerebellum * Is the second largest area. * Controls balance and coordination Diencephalon * Right and left thalamus: relay station for sensory impulses to cerebral cortex. * Hypothalamus: includes optic chiasm and stalk of the pituitary; links the nervous system to the endocrine system; major center for controlling ANS. Brainstem * Midbrain: pupillary reflexes and eye movement; 3rd and 4th cranial nerves * Pons: 5th-8th cranial nerves; conducting pathway; contains portion of respiratory control * Medulla: 9th-12th cranial nerves; vital and non-vital reflexes; RAS Spinal Cord * Consists of 31 segment; each gives rise to a pair of spinal nerves. * Provides conduction pathways to and from the brain. * Functions as a center for reflex action Peripheral Nervous System * Cranial nerves: 12 pairs are numbered according to order in which they arise; conducts impulses between brain and structures in head, nect, thoracic, and abdominal cavities. * Spinal nerves: 31 pairs; each nerve consists of a dorsal (sensory) root and a ventral (motor) root. Autonomic Nervous System
  2. 2. * Involves involuntary or autonomic function. * Impulses are coveyed to smooth muscle, cardiac muscle, and glandular epithelium. * Center is located in the hypothalamus * Two parts; sympathetic and parasympathetic Sympathetic Nervous System Functions * Increases cardiovascular response * Pupil dilation * Decreased peristalsis * Regulates temperature * Increases blood sugar * Increases secretion of sweat glands * Adrenal medulla: epinephrine Parasympathetic Nervous System Functions * 3rd, 7th, 9th, &10th cranial nerves * Pupillary constriction * Decreases heart rate * Stimulates watery secretions * Relaxes bladder and rectal sphincters The Brain's Blood Supply * Vertebral arteries: supplies posterior portion (brainstem, diencephalon, cerebellum, occipital lobes, parts of temporal lobes); unites to form basilar artery which bifurcates into 2 posterior cerebral arteries * Internal carotids: supplies eyes, middle and anterior cerebral arteries. Assessment of the Nervous System * A complete neurological exam is not always possible or necessary. * Baseline date must be obtained. Health History * Current health status * Past medical history * Family history * Review of systems: head, eyes, ears, nose, mouth, musculoskeletal, neurologic Physical Exam * Cerebral functioning: mental status and speech; LOC * Cranial nerves * Cerebellar function * Motor system * Sensory system Mental Status and Speech * Physical appearance * Speech: quality, quantity, organization * Mood and emotional state * Thought processes * Cognitive function
  3. 3. Mood or Emotional State * Is patient approachable? * Ask general questions such as "How do you feel"? * If depression is suspected, ask if they ever get discouraged, what do they see for themselves in the future, and is life worth living? Cognitive Function * Orientation * Attention and concentration * Memory: remote and recent * Information * Vocabulary: start simple * Abstract reasoning: proverbs, similarities, judgement Level of Consciousness * Is an assessment of the patient's state of alertness and mental function. * Must establish a baseline LOC Terms Describing LOC * Dementia * Delirium * Lethargy * Obtundation * Stupor * Coma Motor System * Muscle size * Muscle tone * Involuntary movement * Muscle strength General Guidelines for Sensory Assessment * May get unreliable results if patient is fatigued. * If patient has no neurological deficits, make the exam brief * Compare sensations symmetrically * Compare distal and proximal areas of extremities Sensory System Assessment * Superficial tactile sensations * Superficial pain * Temperature * Vibration See Guide to a Rapid Neurological Assessment Neurological Diagnostic Tests * CAT Scan * Cerebral angiography * Electroencephalography (EEG) * Lumbar puncture CAT Scan * Non-invasive radiologic technique that obtains cross-sectional view
  4. 4. of the body. * Calculates differential absorption of x-ray by tissues in continuous slices. * Diagnose lesions, abscesses cysts, aneurysms * No special precautions or complications Cerebral Angiography * Injection of radiopaque contrast media into carotid or femoral artery. * Pre-test: consent form, NPO, neuro status, IVF, vital signs * Post-test: vital signs, neuro status, bleeding, pressure dressings, ice bags to puncture site, pedal pulses, bedrest for 24 hrs. EEG * Recording of electrical activity of the brain. * Diagnosis of seizures, brain tumors; is a criteria for brain death * No anticonvulsants or sedative before tests; decreased blood sugar may alter results of test. Lumbar Puncture * Insertion of needle into subarachnoid space in 4th lumbar vertebral space. * Therapeutic and diagnostic purpose * Must maintain aseptic technique * Obtain consent * Bedrest for 24 hours * Herniation, infection, headache Intracranial Presure * The cranium contains brain, blood, and CSF * The volumes and pressures of those 3 components are usually in a state of equilibrium. * Causes of increased ICP: head injury, stroke, lesions, brain tumor Signs & Symptoms of Increased ICP * LOC is most important parameter * Lethargy * Initially restlessness, headache, purposeless movements, mental cloudiness * Vital signs: decreased H.R., decreased respirations, increased BP, increased temperature Transient Ischemic Attack * Transient cerebral ischemia with temporary episodes of neurological dysfunction * Focal deficits depend on area of brain involved. * Most common deficits: weakness of lower face, fingers, hands, arms, legs. Transient dysphagia and sensory deficits Cerebrovascular Accident * Most common disease of the nervous system. * Causes: thrombus, embolus, hemorrhage * Sudden impairment of cerebral circulation
  5. 5. * Third most common cause of death in U.S. Factors Increasing Risk of CVA * History of TIA * Atherosclerosis * Hypertension * Arrhythmias * Rheumatic heart disease * Diabetes mellitus * Family history Cerebral Thrombosis * Atherosclerosis is most frequent cause * Onset: during sleep or just after awakening * Symptoms usually worsen for first 48 hours * Symptoms: personality changes, irritability, unhappiness, confusion Cerebral Embolism * Second most common cause of CVA * Affects younger people * Embolus usually originates from a thrombus in the heart. * Develops rapidly * MCA most often affected Clinical Manifestations of CVA * Will vary depending on area of brain affected * Most symptoms are those caused by disruption of blood flow through the MCA * Diagnostic tests CVA Symptoms * Middle cerebral artery: aphasia, dysphagia, visual field cuts, hemiparesis on affected side * Carotid artery: weakness, paralysis, numbness, sensory changes, visual disturbances on affected side, altered LOC, bruits, headaches, aphasia, ptosis CVA Symptoms continued * Vertebrobasilar artery: weakness on affected side, numbness around lips and mouth, visual field cuts, dipolpia, poor coordination, dysphagia, slurred speech * Anterior cerebral artery: confusion, weakness and numbness on affected side, incontinence, loss of coordination, personality changes, motor and sensory Stroke Symptoms continued * Posterior cerebral artery: visual field cuts, sensory impairment, dyslexia, coma Assessment of Stroke Patient: Subjective * Understanding of disease or symptoms * Onset of symptoms * Headache * Sensory deficits
  6. 6. * Visual ability * Cognitive difficulties Assessment of Stroke Patient: Objective * Motor strength * LOC * Signs of increased ICP * Respiratory status * Ability to verbalize Nursing Care Stroke: Thrombus/ Embolus * Prevention * Emergency care * Initial phase * Acute care * Nutritional support * Promote ADLs Intracranial Hemorrhage * Includes bleeding into the subarachnoid space or the brain tissue itself * Third most frequent cause of stroke * Causes: ruptured aneurysm, hypocoagulation, subarachnoid hemorrhage Pathophysiology of Hemorrhagic Stroke * Ruptured blood vessels * Disruption of blood flow * Brain tissue infarction * Unconsciousness * Vasoactive substances * Arterial spasms * Further decrease in cerebral perfusion Diagnosing Hemorrhagic Stroke * CAT scan * Arteriogram * Possible lumbar puncture Medical Management Hemorrhagic Stroke * Evacuation of hematoma * Craniotomy and aneurysm clipping Signs & Symptoms Hemorrhagic Stroke * Sudden explosive headache * Photophobia * Neck rigidity * Loss of consciousness * Convulsions Nursing Care: Hemorraghic Stroke * Move patient gently * Dark room * Bedrest with HOB elevated * No ice water
  7. 7. * Bowel program * No rectal temps, enemas, or suppositories Multiple Sclerosis * A chronic, progressive degenerative disorder of the CNS * Demyelination process and disappearnace of oligodendrocytes * Plaque formatin leads to sclerosis in multiple areas of the CNS Clinical Manifestations of MS * Early symptoms: diplopia, spots before eyes, weakness or numbness, fatigue, upper resp. infection, emotional instability bowel or bladder problems * Progressive symptoms:nystagmus, speech disorders, urinary frequency, changes in muscle coordination, difficult swallowing Assessment of MS * History * Motor * Sensory * Cognition * Psychosocial assessment Treatment of MS * Corticosteroids: ACTH, prednisone, decadron * Antispasmodics: valium and Lioresal * Anticholinergic drugs: Pro-banthind and Ditropan * Immunosuppressive therapy: cytoxan and ACTH combined Nursing Care of MS Patient * Activity and mobility * Physical therapy * Patient education Nursing Diagnoses * Impaired physical mobility * Sensory/Perceptual alterations * Body image disturbance Myasthenia Gravis * Disease of the neuromuscular junction * Results in reduced number of acetylcholine receptor sites * Ach. Molecules are prevented from attaching and causing muscle contraction. Results in loss of muscle strength in skeletal muscle. Clinical Manifestations of MG * Ptosis and diplopia earliest signs * Impaired facial mobility * Difficulty chewing and swallowing * Trunk muscles and limbs less often affected * Proximal muscles of the neck, shoulder, and hip more often affected than distal Diagnostic Studies for MG * Have patient look at ceiling to detect ptosis * EMG to detect muscle fatigue
  8. 8. * Tensilon test: when injected, will reveal improved contractility. If cholinergic crisis, muscle weakness will not improve Myasthenic Crisis * An exacerbation of myasthenia * Will get improved strength following IV anticholinesterase drugs (Tensilon) * Ptosis, difficulty swallowing, dyspnea * Cholinergic Crisis: overdose of anticholinesterase drugs ( won't improve with tensilon) Complications of MG * Muscle weakness in areas which affect swallowing and breathing * Myasthenic crisis * Aspiration, respiratory insufficiency, respiratory infection Nursing Diagnosis: MG * Ineffective airway clearance * Impaired physical mobility * Self care deficit * High risk for injury * Sensory/perception alterations (visual) * Altered nutrition Parkinson's Disease * Due to impairment of the dopamine-producing cells in the mid brain (substantia nigra) * Substantia nigra: part or the extrapyramidal system that influences initiation, modulatin, and completion of movement and regulates unconscious automatic movement. Signs & Symptoms of Parkinson's Disease * Tremor * Rigidity * Bradykinesia Medical Management of Parkinson's Disease * Dopaminergic: Levodopa, Sinemet * Anticholinergic: Cogentin, Artane Nursing Management of Parkinson's Disease * Promote physical exercise * Diet with roughage, small meals * Elimination: constipation * Bradykinesia Alzheimer's Disease * Types of dementia characterized by progressive deterioration in mental functioning and orientation. * Must be distinguished from delirium Signs & Symptoms of Alzheimer's Disease * Initial: subtle deterioration in memory * Later: long-term memory loss * Loss of ability to perform ADLs
  9. 9. Diagnostic Tests * Diagnosis of exclusion * CAT scan: may show brain atrophy and enlarged ventricles in later stages * Definitive diagnosis can only be made after death (neurofibrillary tangles documented) Nursing Management of Alzheimer's Disease * Prevent injury * Promote sleep * promote activity * Prevent agitation/violence *
  10. 10. Diagnostic Tests * Diagnosis of exclusion * CAT scan: may show brain atrophy and enlarged ventricles in later stages * Definitive diagnosis can only be made after death (neurofibrillary tangles documented) Nursing Management of Alzheimer's Disease * Prevent injury * Promote sleep * promote activity * Prevent agitation/violence *