Concept of Sensory Alteration

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Concept of Sensory Alteration
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• Normal Sensory Perception
• Sensory perception depends on the sensory
  receptors, reticular activating system (RAS), and
  functioning nervous pathways to the brain. The
  RAS influences awareness of stimuli, which are
  received through the five senses sight, hearing,
  touch, smell, and taste. Kinaesthetic
• and visceral senses are stimulated internally.
• Reticular activating system (RAS)
• It is responsible for bringing together
  information from the cerebellum and other parts
  of the brain with the sense organs.
• The RAS is highly selective. For example, a
  parent may be awakened in the middle of the night
  at the slightest murmur of an infant in a bedroom
  down the hall but may sleep through the loud
  traffic noises outside the bedroom window.
  Destruction of the RAS produces coma and an
  electroencephalograph pattern characteristic of
  sleep.

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• Input of Senses
• Sensory function begins with reception of stimuli
  by the senses.
• Externally, the senses receiving stimuli are
• Vision, hearing, smell, taste, and touch.
• Receptor organs are
• The eyes, ears, olfactory receptors in the nose,
  taste buds of the tongue, and nerve endings in
  the skin.
• Internally, the kinaesthetic and visceral senses
  receive stimuli. These receptors are nerve
  endings in the skin and body tissues. The
  kinaesthetic sense influences awareness of the
  placement and action of body parts. The visceral
  sense receives stimuli that affect awareness
  related to the body's large interior organs.
  Vision, hearing, smell, and taste are termed,
  special senses. Touch, kinesthetic sensation, and
  visceral sensation are termed somatic senses.
  After stimuli are received, they are perceived
  with the help of the RAS. Sensory perception is a
  consociates process of selecting, organizing, and
  interpreting sensory stimuli requiring intact and
  functioning sense organs, nervous pathways, and
  the brain.

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• Characteristics of Normal Sensory Perception
• These are the normal measures in quality and
  quantity of the special and somatic senses.
• Normal vision is associated with visual acuity at
  or near 20/20, full field of vision, and
  tricolour vision (red, green, blue).
• Normal hearing is associated with auditory acuity
  of sounds at an intensity of 0 to 25 dB, at
  frequencies of 125 to 8,000 cycles per second.
• Normal taste involves the ability to discriminate
  sour, salty, sweet, and bitter.
• Normal smell involves the discrimination of
  primary odours, such as cainphoraceotrs, musky,
  floral, peppermint, ethereal, pungent, and
  ptitrid.
• Somatic senses include discrimination of touch,
  pressure, vibration, position, tickling,
  temperature, and pain.

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• Normal Sensory Pattern
• Sensor stasis
• Each person has his or her own comfort zone.
  This comfort zone varies from person to person
  and is the range at which a person performs at
  his or her peak. Sensor stasis is a state of
  optimum arousal-not too much and not too little.
  The RAS is viewed by some theorists as a monitor
  for sensor static balance.
• Adaptation
• Beyond the point of sensor stasis, sensory
  adaptation occurs. Sensory receptors adapt to
  repeated stimulation by responding less and less.
  Lead time and after burn are two necessary time
  periods crucial to helping a person deal with new
  stimuli.
• Lead time is the time each person needs to
  prepare for an event emotionally and physically.
• After burn is the time needed to think about,
  evaluate, and come to terms with the activity
  after it happens.
• The necessary amount of lead time and after burn
  is different for each person. Lead time and after
  burn helps person process stimuli so he or she
  can respond appropriately without becoming
  overwhelmed.

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• Factors Affecting Sensory Perception
• Environment
• Sensory stimuli in the environment affect sensory
  perception. For example, a teacher may not notice
  the noise in a consistently noisy environment,
  such as the school cafeteria. But the same
  teacher may perceive a loud television set very
  differently in his or her own home, which is
  usually quiet.
• Previous Experience
• It affects sensory perception in that people
  become more alert to stimuli that evoke a strong
• response. For example, a person may drive to work
  by the same route each day, noticing little along
  the way. A person may listen to the radio
  inattentively until a favourite song is played,
  then listen to every word. A new experience, such
  as hospitalization, may cause a client to
  perceive a barrage of threatening new stimuli.

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• Lifestyle and Habits
• It affects sensory perception. One person may
  enjoy a lifestyle surrounded by many people,
  frequent changes, bright lights, and noise.
  Another person may prefer less contact with
  crowds, less noise, and a slow-paced routine.
  People with different lifestyles perceive stimuli
  differently.
• Cigarette smoking causes atrophy of taste buds,
  decreasing sensory perception of taste. Chronic
  alcohol abuse may lead to peripheral neuropathy,
  a functional disorder of the peripheral nervous
  system those results in sensory impairment.
• Illness
• Certain illnesses affect sensory perception.
  Diabetes and hypertension cause changes in blood
  vessels and nerves, leading to visual deficits
  and decreased sensation of touch in the
  extremities. Cerebrovascular disorders impair
  blood flow to the brain, possibly blocking
  sensory perception. Pain, fatigue, and stress
  caused by illness also affect perception of
  stimuli.

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• Medications
• Some antibiotics, including streptomycin and
  gentamicin, can damage the auditory nerve,
  impairing hearing. Central nervous system (CNS)
  depressants, such as narcotic analgesics,
  decrease awareness and impair perception of
  stimuli.
• Variations in stimulation
• If a person experiences more sensory stimulation
  than he or she is used to or can make sense of,
  distress and sensory overload may occur.
• On the other hand, if a person experiences less
  than the usual stimulation, that person is below
  his or her optimum state of arousal and may be at
  risk for sensory deprivation.
• Reactions to sensory overload or sensory
  deprivation are special challenges that nurses
  frequently encounter in themselves and clients.
  Sensory overload and deprivation can lead to
  perceptual, cognitive, and decisional problems.
  When the RAS is overwhelmed with input, a person
  may experience sensory overload and feel
  confused, anxious, and unable to taken
  constructive action . When the RAS fails to
  recognize a stimulus because it is below the
  threshold level or lacks relevant meaning to the
  person, sensory deprivation may occur, and the
  person experiences depression, restlessness, and
  hallucinations

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• Sensory overload
• It occurs when a person is unable to process or
  manage the intensity or quantity of incoming
  sensory stimuli. The person feels out of control
  and overwhelmed by the excessive input from the
  environment. Routine activity in the health
  setting can contribute to sensory overload in
  clients.
• These activities fall into three main categories
  
• internal factors,
• information, and
• environment .
• Internal Factors
• such as thinking about surgery or the meaning of
  a medical diagnosis, can contribute to anxiety
  and cognitive overload so that the person cannot
  process additional stimuli. Pain, medication,
  lack of sleep, worry, and brain injury also can
  contribute to a person's vulnerability to sensory
  overload.

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• Information
• It is Imparting information to a client may lead
  to sensory overload. Some examples include
  teaching a client about a procedure, informing a
  client about a diagnosis, making requests of a
  client, or helping the client solve a problem.
  Anxiety related to medical diagnosis, prognosis,
  and treatment can contribute to sensory overload.
  Lights and frequent activity may cause sensory
  overload in a premature newborn in the neonatal
  intensive care unit.
• Environment
• The environment of the healthcare agency provides
  a higher than usual amount of sensory
  stimulation. A client newly admitted to the
  hospital, for example, may have to cope with
  adjusting to a new roommate, having the
  television on more than usual, bright lights,
  paging systems, meeting many staff members,
  having the bed move up and down at someone else's
  bidding, waiting for someone to answer the call
  light, uncontrolled pain, and having strangers
  touch and not respect private body areas. Clients
  in intensive care units often exhibit symptoms of
  sensory overload because of the high degree of
  light, noise, and activity around the clock.

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• Sensory Deprivation
• Although sensory deprivation can be thought of as
  the opposite of sensory overload, they share many
  elements.
• Sensory deprivation generally means a lessening
  or lack of meaningful sensory stimuli, monotonous
  sensory input, or an interference with the
  processing of information.

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• Sensory deprivation (under stimulation)
• It can be just as disruptive as sensory
  overload. Cognitive and emotional deterioration
  can occur when stimuli are reduced below a
  person's optimum level of stimulation. One common
  source of sensory deprivation is a sudden
  decrease in stimuli when a person moves from a
  fast- to a slow-paced environment.
• Each person's tolerance of and reaction to a
  lessening or lack of meaningful sensory stimuli
  differs, but clients with extreme cases
  experience a gross misperception of events and
  personality changes. Any time a client
  experiences an interference with or a diminution
  of sensory input, that person may be at risk for
  sensory deprivation.
• In the hospital such occurrences fall into two
  general categories
• altered sensory reception
• deprived environments

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• Altered sensory reception
• Occurs in such conditions as spinal cord injury,
• brain damage, changes in receptor organs, sleep
  deprivation, and chronic illness. The person does
  not receive adequate sensory input because of an
  interference with the nervous system's ability to
  receive and process stimuli.
• Deprived environments
• It can have negative effects on a person's sensor
  stasis. A person who is immobilized or isolated
  for any reason is deprived of the usual amount of
  stimulation and may show manifestations of
  sensory deprivation

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• Manifestations of Altered Sensory Perception
  Function
• Anxiety
• Cognitive Dysfunction, which is a Disturbance in
  remembering, reasoning, and problem solving may
  occur with sensory overload.
• Hallucination and Delusions (beliefs not based in
  reality) reflect an unconscious need or fear
• Sensory Deficit
• Depression and withdrawal

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• Impact on Activities of Daily Living
• Sensory perception dysfunction may have effects
  on activities of daily living (ADLs). Visual
  deficits cause problems with self-care activities
  as basic as dressing, toileting, and preparing
  meals. Hearing deficits may restrict people from
  watching television, listening to the radio, and
  answering the telephone. Safety hazards also
  exist for who are hearing impaired.
• People with taste and smell deficits may lose
  interest in eating.
• Those with sensory deficits involving touch are
  at risk for burns and injuries to the
  extremities. Moving around outside the home may
  be impossible without special aids or help .
• Many jobs are prohibited for people with sensory
  deficits, and driving may not be allowed.
• This further restricts the environments in which
  they may move about safely, making them dependent
  on others. If the affected person is the major
  wage earner, a reduction in or loss of income may
  occur.
• People with cognitive dysfunction from sensory
  overload or deprivation may exhibit poor judgment
  and problem solving during everyday activities,
  increasing the necessity for family members to
  monitor activities and decisions.
• All these concerns place more stress on the
  family to cope with sensory
• dysfunctions.

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• Risk Factors for Sensory Perception Dysfunction
  in the Healthcare Environment
• Sensory Overload
• Room close to nurse's station
• ICU or intermediate unit
• Bright lights
• Use of mechanical ventilator
• Use of ECG monitor
• Use of oxygen
• Use of IVs
• Other equipment
• Frequent treatments
• Sensory Deprivation
• Private room
• Eyes bandaged
• Bed rest
• Sensory aid not available (hearing aid, glasses)
• Isolation precautions
• Few visitors

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• Diagnostic Statement
• Sensory/Perceptual Alterations
• Definition Sensory/perceptual alteration is a
• state in which a person experiences a change in
  the amount or patterning of oncoming stimuli,
  accompanied by a diminished, exaggerated,
  distorted, or impaired response to such stimuli
  (NANDA, 1999) .
• Nurse-Client Interaction
• It promotes sensory health function. Clients at
  risk for sensory deprivation may need frequent
  interaction initiated by the nurse. In any case,
  provide appropriate stimuli, such as addressing
  The Client by name, explaining all activities,
  and, when leaving, acknowledging client that the
  nurse will return. Length, tendency, and content
  of interactions should he based on individual
  needs. Talking to the client, showing the client
  equipment or articles used in care, encouraging
• the client to smell and taste food that is
  served, and touching the client are appropriate
  stimuli during interactions

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• Nursing Interactions for Altered
• Sensor- Perception function Stimulation
• Providing meaningful external stimuli can help a
  client overcome sensor' deprivation or sensory
  deficit as playing the television or the radio
  occasionally. playing tennice,
• Encouraging use of a clock and calendar,
• Encouraging the client to dress or the day's
  activities, putting till pictures,
• Encouraging visitors, opening the drapes, and
  turning on lights.
• Plan the bed or chair so the client can see or
  hear activities in the area.