concept of sensory alteration

7/30/2019 Concept of Sensory Alteration

1/41

Altered

Sensory Perception


2/41

The visual, auditory and olfactory systems

are distance senses, bringing informationabout our environment to our perception.

Each system detects the intensity and

quality of stimuli, encodes and processesthis information, and transmits it to the

cerebral cortex. Together these senses

provide much of the available information

about our environment


3/41

CLASSIFICATION OF SENSE

ORGANS GENERAL SENSE ORGANS

microscopic receptors widely distributed

throughout the body in the skin, muscles,

tendons, joints and other internal organs of

the body

SPECIAL SENSE ORGANS

The special sense organs are responsible

for the special senses of smell, taste,

vision, hearing and equilibrium


4/41

Normal Sensory Perception Sensory perception depends on the sensory receptors,

reticular activating system (RAS), and functioning

nervous pathways to the brain. The RAS influencesawareness of stimuli, which are received through the fivesenses: sight, hearing, touch, smell, and taste.Kinaesthetic and visceral senses are stimulatedinternally.

Reticular activating system (RAS) It is responsible for bringing together information from

the cerebellum and other parts of the brain with thesense organs.

The RAS is highly selective. For example, a parent may

be awakened in the middle of the night at the slightestmurmur of an infant in a bedroom down the hall but maysleep through the loud traffic noises outside the bedroomwindow. Destruction of the RAS produces coma and anelectroencephalograph pattern characteristic of sleep.


5/41

NEURAL PATHWAYS

SENSORY IMPULSES TRAVEL TO THE

BRAIN VIA

2 ASCENDING NEURAL PATHWAYS

SPINO-THALAMIC TRACT &

POSTERIOR COLUMNS

IMPULSES ORIGINATE IN THE

AFFERENT FIBERS OF THEPERIPHERAL NERVES, ARE CARRIED

THROUGH THE POSTERIOR DORSAL

ROOT INTO THE SPINAL CORD


6/41

LATERAL SPINOTHALAMIC

TRACT PAIN

TEMPERATURE

CRUDE & LIGHT TOUCH


7/41

POSTERIOR COLUMNS

POSITION

VIBRATION

FINE TOUCH


8/41

COMPONENTS OF SENSORY

PERCEPTION

RECEPTION

Reception is the process of receiving stimuli from

nerve endings in the skin and body. A receptor

converts a stimulus to a nerve impulse andtransmits the impulse along sensory neurons to

the CNS


9/41

COMPONENTS OF SENSORY

PERCEPTIONPERCEPTION:

It is the ability to interpret the impulses

transmitted from the receptors and give meaning

to the stimuli. After the receptors generate nerveimpulses, the impulses travel along the neural

pathways to the spinal cord and brain. They are

then relayed to the specialized locations in the

brain where perception of the stimuli occurs


10/41

Input of SensesSensory function begins with reception of stimuli by the senses.

Externally, the senses receiving s t imu l i are;

Vision, hearing, smell, taste, and touch.

Receptor o rgans are

The eyes, ears, olfactory receptors in the nose, taste buds of thetongue, 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 placementand action of body parts. The visceral sense receives stimuli thataffect 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 termedsomatic senses. After stimuli are received, they are perceived

with the help of the RAS. Sensory perception is a consociatesprocess of selecting, organizing, and interpreting sensory stimulirequiring intact and functioning sense organs, nervous pathways,and the brain.


11/41

Characteristics of Normal Sensory Perception These are the normal measures in quality and quantity

of the special and somatic senses.

Normal vis ionis associated with visual acuity at or near20/20, full field of vision, and tricolour vision (red,green, blue).

Normal hearingis associated with auditory acuity ofsounds at an intensity of 0 to 25 dB, at frequencies of

125 to 8,000 cycles per second. Normal tasteinvolves the ability to discriminate sour,

salty, sweet, and bitter.

Normal smellinvolves the discrimination of primary

odours, such as cainphoraceotrs, musky, floral,peppermint, ethereal, pungent, and ptitrid.

Somatic sensesinclude discrimination of touch,pressure, vibration, position, tickling, temperature, andpain.


12/41

Normal Sensory Pattern

Sensor stasis

Each person has his or her own comfort zone.

This comfort zone varies from person to personand is the range at which a person performs athis or her peak. Sensor stasis is a state ofoptimum arousal-not too much and not toolittle. The RAS is viewed by some theorists as a

monitor for sensor static balance. Adaptation

Beyond the point of sensor stasis, sensoryadaptation occurs. Sensory receptors adapt to

repeated stimulation by responding less andless. Lead time and after burn are twonecessary time periods crucial to helping aperson deal with new stimuli.


13/41

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 becomingoverwhelmed


14/41

Factors Affecting Sensory Perception

Environment

Sensory stimuli in the environment affect sensory

perception. For example, a teacher may not noticethe noise in a consistently noisy environment, suchas the school cafeteria. But the same teacher mayperceive a loud television set very differently in hisor her own home, which is usually quiet.

Previous Experience

It affects sensory perception in that people becomemore alert to stimuli that evoke a strong

response. For example, a person may drive to workby the same route each day, noticing little along theway. A person may listen to the radio inattentivelyuntil a favourite song is played, then listen to everyword. A new experience, such as hospitalization,may cause a client to perceive a barrage ofthreatening new stimuli.


15/41

Lifestyle and Habits

It affects sensory perception. One person may enjoy alifestyle surrounded by many people, frequent changes,bright lights, and noise. Another person may prefer less

contact with crowds, less noise, and a slow-pacedroutine. People with different lifestyles perceive stimulidifferently.

Cigarette smoking causes atrophy of taste buds,decreasing sensory perception of taste. Chronic alcohol

abuse may lead to peripheral neuropathy, a functionaldisorder of the peripheral nervous system those resultsin sensory impairment.

Illness

Certain illnesses affect sensory perception. Diabetes

and hypertension cause changes in blood vessels andnerves, leading to visual deficits and decreasedsensation of touch in the extremities. Cerebrovasculardisorders impair blood flow to the brain, possiblyblocking sensory perception. Pain, fatigue, and stress

caused by illness also affect perception of stimuli.


16/41

Medications

Some antibiotics, including streptomycin and gentamicin, candamage the auditory nerve, impairing hearing. Central nervoussystem (CNS) depressants, such as narcotic analgesics, decreaseawareness 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 mayoccur.

On the other hand, if a person experiences less than the usualstimulation, 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 andclients. Sensory overload and deprivation can lead to perceptual,cognitive, and decisional problems. When the RAS is overwhelmedwith input, a person may experience sensory overload and feel

confused, anxious, and unable to taken constructive action . Whenthe RAS fails to recognize a stimulus because it is below thethreshold level or lacks relevant meaning to the person, sensorydeprivation may occur, and the person experiences depression,restlessness, and hallucinations


17/41

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 theexcessive input from the environment. Routine activity inthe health setting can contribute to sensory overload inclients.

These activ i t ies fal l into three main catego ries:

internal factors, information, and

environment .

Internal Facto rs;

such as thinking about surgery or the meaning of amedical diagnosis, can contribute to anxiety andcognitive overload so that the person cannot processadditional stimuli. Pain, medication, lack of sleep, worry,and brain injury also can contribute to a person's

vulnerability to sensory overload.


18/41

Informat ion; 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, orhelping the client solve a problem. Anxiety related to medical

diagnosis, prognosis, and treatment can contribute to sensoryoverload. Lights and frequent activity may cause sensory overload ina premature newborn in the neonatal intensive care unit.

Envi ronment ;

The environment of the healthcare agency provides a higher thanusual amount of sensory stimulation. A client newly admitted to thehospital, for example, may have to cope with adjusting to a newroommate, having the television on more than usual, bright lights,paging systems, meeting many staff members, having the bed moveup and down at someone else's bidding, waiting for someone toanswer the call light, uncontrolled pain, and having strangers touchand not respect private body areas. Clients in intensive care unitsoften exhibit symptoms of sensory overload because of the highdegree of light, noise, and activity around the clock.


19/41

Sensory Deprivation

Although sensory deprivation can bethought of as the opposite of sensory

overload, they share many elements.

Sensory deprivation generally means a

lessening o r lackof meaningful

sensory stimuli, monotonous sensory

input, or an interference with the

processing of information.


20/41

Sensory deprivat ion (under st imu lat ion)

It can be just as disruptive as sensory overload. Cognitiveand emotional deterioration can occur when stimuli are

reduced below a person's optimum level of stimulation.One common source of sensory deprivation is a suddendecrease in stimuli when a person moves from a fast- to aslow-paced environment.

Each person's tolerance of and reaction to a lessening or

lack of meaningful sensory stimuli differs, but clients withextreme cases experience a gross misperception ofevents and personality changes. Any time a clientexperiences an interference with or a diminution ofsensory input, that person may be at risk for sensorydeprivation.

In the hospital such occurrences fall in to two generalcategories: altered sensory reception

deprived environments;


21/41

A ltered senso ry recept ion

Occurs in such conditions as spinal cord injury,

brain damage, changes in receptor organs,sleep deprivation, and chronic illness. Theperson does not receive adequate sensoryinput because of an interference with thenervous system's ability to receive and process

stimuli.

Deprived env ironments

It can have negative effects on a person's

sensor stasis. A person who is immobilized orisolated for any reason is deprived of the usualamount of stimulation and may showmanifestations of sensory deprivation


22/41

Manifestations of Altered SensoryPerception Function

Anxiety Cognitive Dysfunction, which is a

Disturbance in remembering, reasoning, andproblem 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


23/41

Impact on Activities of Daily Living Sensory perception dysfunction may have effects on activities of

daily living (ADLs). Visual deficits cause problems with self-careactivities 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 hazardsalso 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 andinjuries to the extremities. Moving around outside the home may beimpossible without special aids or help .

Many jobs are prohibited for people with sensory deficits, and drivingmay not be allowed.

This further restricts the environments in which they may move aboutsafely, making them dependent on others. If the affected person isthe major wage earner, a reduction in or loss of income may occur.

People with cognitive dysfunction from sensory overload ordeprivation may exhibit poor judgment and problem solving duringeveryday activities, increasing the necessity for family members tomonitor activities and decisions.

All these concerns place more stress on the family to cope with sensory

dysfunctions.


24/41

Risk Factors for Sensory Perception Dysfunction in theHealthcare Environment

Sensory Over load

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 Depr ivat ion

Private room

Eyes bandaged

Bed rest

Sensory aid not available (hearing aid, glasses)

Isolation precautions

Few visitors


25/41

SENSORY DEFICITS:

Impaired or absent functioning in one or

more senses are termed as sensory

deficits

Eg: impaired sight and hearing, altered

taste, numbness and paralysis that results

in altered tactile perception, and impaired

kinaesthetic sense


26/41

Impaired vision:

Vision occurs when light rays that focus onthe retina trigger a nerve impulse that is

transmitted to the visual area of brain in

the occipital region. Visual deficits mayresults from trauma or diseases of the eye,

microvascular problems, or CNS

disorders. Common causes of visual

deficits include refractive errors, orbitaltrauma, cataracts, glaucoma, diabetic or

hypertensive retinopathy, or loss of visual

field after stroke.


27/41

Impaired hearing :

Hearing occurs when sound wavesentering the ear canal are converted to

vibrations and transferred from the middle

ear to the inner ear. Vibrations cause thehair cells in the cochlea to bend,

generating impulses that are carried by

cranial nerveVIII to the brain. The auditory

area in the brain is located in the temporallobes. The auditory area interprets the

sound and and allows you to determine

from which direction the noise is coming.


28/41

IMPAIRED HEARING

Hearing deficits may result from injury or

diseases in the structures of the ear, the

nerves or the brain. Inability to hear

decreases the ability to communicate andhampers social interaction. It may interfere

with a persons ability to understand

instructions from health care professionalsand create a safety hazard due to inability

to hear warnings.


29/41

IMPAIRED TASTE

taste imparts interest to food. Taste deficits may decrease

the pleasure associated with eating; weight loss andmalnutrition may result.

Taste depends on the functioning of the taste buds

on the tongue and, to a lesser extent, on the soft palate.

Four types of taste buds exist: sweet, sour, salt, and

bitter. The buds for sweet and salty tastes are primarilyon the tip of the tongue; for sour taste, on the lateral

sides of the tongue; and for bitter taste, primarily on the

posterior tongue and the soft palate. When stimulated,

taste buds generate nerve impulses that travel along thefacial and glossopharyngeal nerves (cranial nerves VII

and IX, respectively) to the taste area in the parietal-

temporal cortex.


30/41

Impaired smell

The sense of smell is triggered when chemoreceptors in the upper nasal cavities detect

vaporized chemicals. Chemo receptors generate

impulses carried by the olfactory nerve (CN I) into the olfactory area in the temporal

lobes. Vaporized molecules can be detected

from a far distance, so the sense of smell can

serve as an early warning system for detection

of smoke and noxious chemicals.


31/41

Causes : impaired smell

cranial nerve damage,

a tumor, or atherosclerosis.

Zinc deficiency, heavy smoking, cocaineuse,

rhinitis, and sinusitis can cause reversible

anosmia.


32/41

Impaired tactile perception

The dermis of the skin contains receptors

for the cutaneous sensation of light touch,

pressure, heat, cold and pain. Information

from these receptors is transmitted to thesensory areas in parietal lobes. The

number of cutaneous receptors

determines the sensitivity of an area andthe amount of space devoted to the region

in the sensory cortex area.


33/41

Impaired tactile perception

contd.. Loss of tactile sensitivity: causes:-

cerebrovascular accident, brain or spinal tumor or injury, or

peripheral nerve damage caused by

diabetes, GBS, or chronic alcoholism.


34/41

Impaired kinaesthetic sense:

Kinaesthesia or muscle sense, is a

complex process involving propioceptors

that detect stretch in muscles to create a

mental picture of how the body ispositioned. Conscious muscle sense is

perceived in the parietal lobes.

Unconscious muscle sense occurs in thecerebellum, which co-ordinates

movement.


35/41

Impaired kinaesthetic sense:

causes Parkinsons disease,

other neurologic disorders,

tumors, CVA, and

certain medication


36/41

ASSESSMENT

SCATTER STIMULI OVER THE DISTALAND PROXIMAL PART OF ALL

EXTREMITIES AND TRUNK TO COVER

MOST OF THE DERMATOMES.

ABNORMAL SYMPTOMS MAY

INDICATE NEED TO TEST THE ENTIRE

BODY SURFACE.

PAIN

NUMBNESS

TINGLING


37/41

Assessment contd.

COMPARE SENSATION ON

SYMMETRIC PARTS OF THE BODY

IF DECREASE IN SENSATION

SYSTEMATIC TESTING

FRON POINT OF DECREASED

SENSATION TOWARD SENSITIVE

AREA

NOTE WHERE SENSATION CHANGES

MAP BORDERS OF DEFICIENT AREA

Assessment contd


38/41

Assessment contd..

NOTE, IF THE PATTERN OF SENSORY

LOSS IS DISTAL

GLOVE AND STOCKING (HANDS &

FEET)

DERMATONES

C3-FRONT OF NECK

T10-UMBILICUS C6-THUMB

L1-INGUINAL


39/41

Diagnostic Statement:


40/41

Diagnostic Statement: Senso ry/Perceptual A lterat ions

Defin i t ion;Sensory/perceptual alteration is a

state in which a person experiences a change in the amount orpatterning 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 Clientby name, explaining all activities, and, when leaving, acknowledgingclient that the nurse will return. Length, tendency, and content ofinteractions should he based on individual needs. Talking to theclient, showing the client equipment or articles used in care,encouraging

the client to smell and taste food that is served, and touching theclient are appropriate stimuli during interactions


41/41

Nursing Interactions for Altered

Sensor- Perception function Stimulation

Providing meaningful external stimuli can helpa 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, andturning on lights.

Plan: the bed or chair so the client can see or

hear activities in the area.

concept of sensory alteration

Documents