Common neurologic disorders

Below are several common neurologic disorders, along with their causes, pathophysiology, signs and symptoms, diagnostic test findings, treatments, and nursing interventions.

Common neurologic disorders: Alzheimer’s disease

Alzheimer’s disease is a progressive neurologic disorder that affects the brain and results in cognitive impairments, such as impaired thinking, memory loss, and bizarre behavior. Alzheimer’s disease is the most common form of dementia and the fourth leading cause of death in adults.

What causes it

The cause of Alzheimer’s disease isn’t known; however, several factors appear to have some association with the disease. These include:

  • deficiencies in the neurotransmitters acetylcholine, somatostatin, substance P, and norepinephrine
  • repeated head trauma
  • abnormalities on chromosomes 14 or 21
  • deposits of beta amyloid protein

Pathophysiology

The brain tissue of patients with Alzheimer’s disease has three distinguishing features:

  1. neurofibrillatory tangles (fibrous proteins)
  2. amyloid plaques (composed of degenerating axons and dendrites)
  3. granulovacuolar degeneration.

Autopsy commonly reveals an atrophic brain that can weigh 1,000 g or less. Normal brain weight is 1,380 g. (See Brain tissue changes in Alzheimer’s disease.)

What to look for

The onset of Alzheimer’s disease is insidious. Initial changes are almost imperceptible, but gradually progress to serious problems. Initial signs and symptoms include:

  • forgetfulness and short-term memory loss
  • difficulty learning and remembering new information
  • deterioration in personal hygiene and appearance
  • inability to concentrate

Later signs and symptoms include:

  • difficulty with abstract thinking and activities that require judgment
  • progressive difficulty communicating
  • severe deterioration in memory, language, and motor function
  • repetitive actions or perseveration (a classic sign)
  • nocturnal wakening, disorientation, and personality changes, such as restlessness and irritability

Brain tissue changes in Alzheimer’s disease

Common neurologic disorders

 

What tests tell you

  • Psychometric testing and neurologic examination can help establish the diagnosis.
  • A PET scan measures the metabolic activity of the cerebral cortex and may help confirm an early diagnosis.
  • EEG, CT scan, and MRI may help diagnose later stages of Alzheimer’s disease.
  • Testing for soluble amyloid beta protein precursor helps assess the extracellular deposits of amyloid beta-peptide, which is a major neuropathic sign of Alzheimer’s disease.
  • Additional tests may help rule out other causes of dementia, such as vitamin B12 deficiency and hypothyroidism.

How it’s treated

Although there’s no known cure for Alzheimer’s disease, donepezil, tacrine, and rivastigmine have proven partially effective in improving mental performance. Drug therapy is also used to treat behavioral symptoms, such as aggression, paranoia, depression, and delusions. These drugs include:

  • antipsychotics, such as haloperidol (Haldol), olanzapine (Zyprexa), quetiapine (Seroquel), and risperidone (Risperdal)
  • anxiolytics, such as alprazolam (Xanax), buspirone (BuSpar), diazepam (Valium), and lorazepam (Ativan)
  • antidepressants, such as amitriptyline, bupropion (Wellbutrin), fluoxetine (Prozac), and paroxetine (Paxil).

What to do

  • Establish an effective communication system with the patient and his family to help them adjust to his altered cognitive abilities.
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Common neurologic disorders: Returning to a safe haven

    • Protect the patient from injury by providing a safe, structured, and supervised environment.
    • Encourage the patient to exercise, as ordered, to help maintain mobility.
    • Refer family members to appropriate social service agencies that can help the family assess its needs.
    • Evaluate the patient. He should be free from injury; have an established, adequate sleep pattern; and have adequate nutrition.
    • Assess the patient’s family to determine if they have sufficient support systems to help them cope with this crisis.
    • Encourage the patient and his family to express their feelings of loss. (See Alzheimer’s disease teaching tips.)

 

Common neurologic disorders: Alzheimer’s disease teaching tips

  • Teach the patient and his family about Alzheimer’s disease — what’s known, what’s suspected, and the degenerative nature of the disorder. Listen to their concerns and answer all questions honestly and with compassion.
  • Refer the family to local and national support groups for additional information and coping strategies. Family members commonly find a degree of solace in knowing that other families are going through the same devastating experience. To locate support groups in your area, contact the Alzheimer’s Disease and Related Disorders Association.
  • Encourage the family to allow the patient as much independence as possible while keeping him safe.
  • Explain how proper diet, regular daily routines, and normal sleep patterns can help.

Common neurologic disorders: Amyotrophic lateral sclerosis

ALS causes progressive physical degeneration while leaving the patient’s mental status intact. Thus, the patient is keenly aware of each new physical change. The most common motor neuron disease of muscular atrophy, ALS results in degeneration of upper motor neurons in the medulla oblongata and lower motor neurons in the spinal cord.

Onset typically occurs between ages 40 and 70, and most patients die within 3 to 10 years, usually due to aspiration pneumonia or respiratory failure.

What causes it

The cause of ALS isn’t known; however, factors associated with ALS include:

  • autosomal dominant inheritance
  • a slow-acting virus
  • a nutritional deficiency in motor neurons related to a disturbance in enzyme metabolism
  • metabolic interference in nucleic acid production by the nerve fibers
  • an autoimmune disorder.

Precipitating factors for acute deterioration include trauma, viral infections, and physical exhaustion.

Pathophysiology

In ALS, motor neurons located in the anterior horns of the spinal column and motor nuclei located in the lower brain stem die. As they die, the muscles they served begin to atrophy. The loss of motor neurons may occur in the upper and lower motor neuron systems. Signs and symptoms vary according to the motor neurons affected because specific neurons activate specific muscle fibers.

What to look for

The patient with ALS develops fasciculations (twitching, involuntary muscle contractions) accompanied by atrophy and weakness, especially in the muscles of the forearms and hands. Other signs and symptoms include:

  • impaired speech
  • difficulty chewing and swallowing
  • difficulty breathing
  • depression
  • choking
  • excessive drooling.

What tests tell you

  • Electromyography and muscle biopsy help determine if the disease is affecting the nerves rather than the muscles.
  • In one-third of all patients with ALS, cerebrospinal fluid (CSF) examination reveals an increased protein level.

How it’s treated

No effective treatment exists for ALS. Management focuses on controlling symptoms and providing the patient and his family with the emotional, psychological, and physical support they need. Care begins with a complete neurologic assessment, which functions as a baseline for future evaluations. Collectively, these assessments will reveal the progression of ALS over time.

What to do

  • Implement a rehabilitation program that maintains as much independence for the patient for as long as possible.
  • Help the patient obtain equipment that will help him move about, such as a walker or a wheelchair. Arrange for a visiting nurse to oversee home care and provide ongoing support, and to teach the family about the illness.
  • Depending on the patient’s muscular ability, help with bathing, personal hygiene, and transfers from wheelchair to bed, as needed. Encourage a regular bowel and bladder routine.
  • Provide meticulous skin care if the patient is bedridden, to prevent skin breakdown. Also, turn him often, keep his skin clean and dry, and use pressure-relieving devices to preserve skin integrity.
  • If the patient has trouble swallowing, give him soft, solid foods and position him upright during meals. He’ll need gastrostomy and nasogastric (NG) tube feedings when he’s no longer able to swallow.
  • Provide the patient and family with information on support groups.

Common neurologic disorders: Making informed decisions

  • Provide the patient and his family with emotional support and the information they need to make informed decisions regarding end-of-life care and help them prepare for the eventual death of the patient. Encourage all concerned to start the grieving process. The patient with ALS may benefit from a hospice program.
  • Evaluate the patient. Intervene as needed to maintain adequate respiratory function with a patent airway, clear lungs, and acceptable results from pulmonary function studies. Help maintain a system of communication and as much physical mobility as possible for as long as possible. Note whether the patient expresses feelings of loss. (See ALS teaching tips.)

Common neurologic disorders: ALS teaching tips

  • Teach one or more family members the proper way to suction the patient. This will help the patient cope with the increasing accumulation of secretions and dysphagia.
  • Explain that he must eat slowly at mealtime and always sit upright. If he develops swallowing difficulties, refer him to the dysphagia team for further evaluation and treatment.
  • If the patient is still able to feed himself, teach him (and a family member) how to administer gastrostomy feedings.
  • When verbal communication becomes too difficult, teach the patient an alternate method of communicating with those around him.
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