Altered Sensory Function

Sensory Alterations Meaningful sensory stimuli provide information about a person’s environment and are necessary for healthy functioning and normal development. Altered sensory function can result in: -decreased ability to manage self-care tasks -altered communication & cognition -altered socialization -altered sense of self -altered mobility -nutritional problems -safety risks Sources of Sensory Stimulation come from outside and inside the body, and include: Visual- sight Auditory- hearing Tactile- touch Olfactory- smell Gustatory- taste Kinesthetic- awareness of own position and movement of extremities without seeing them. Stereognosis- recognize an object through touch. Normal Sensation- There are 3 parts to all sensory experiences: 1. Reception- sensory receptor is stimulated 2. Perception- the stimulus reaches the brain, and the person becomes conscious of the stimuli -Affected by LOC -Affected by prior experiences 3. Reaction to Sensory Stimuli- only the most important stimuli will elicit a reaction. -remainder are discarded or stored for later (prevents sensory overload). Reticular Activating System (RAS): a part of the brain stem that mediates all sensory stimuli to cerebral cortex. -strives to maintain homeostasis by increasing or decreasing arousal of cortex (prevent deprivation or overload). -even in deep sleep, you can still receive stimuli (full bladder, baby crying) Adaptability: with repeated exposure to the same stimulus, brain ignores stimulus Exception: PAIN Sensory Alterations- Three Main Types: 1. Sensory Deficit: loss in the normal function of sensory reception and perception. -sudden losses can result in fear, anger, helplessness, impairs sense of self. -reaction to loss may be effective or ineffective -if occurs gradually, or has existed for a long while person relies more on unaffected senses Person with sensory deficit has an increased risk for sensory deprivation. Common Sensory Deficits: Visual: -presbyopia -cataract -dry eyes -glaucoma -diabetic retinopathy -macular degeneration -retinal detachment Auditory: -conductive hearing loss -presbycusis -central auditory processing disorders -cerumen accumulation -otosclerosis -Meniere’s disease -ottis media -sensorineural hearing loss Balance: -benign positional vertigo Taste: -xerostomia -taste alterations 2. Sensory Deprivation: occurs when sensory input is insufficient to maintain cortical arousal necessary to maintain a person’s awareness Amount of stimuli is insufficient. Quality of stimuli is inadequate. - Results in monotony (lack of variety and interest) and boredom. Symptoms of sensory deprivation can be mistaken for psychosis, confusion, electrolyte imbalance, etc. Examples: -Reduced capacity to learn -Decreased ability to think/problem solve -Disorientation -Bizarre thinking -Rapid mood swings -Boredom, restlessness -Increase anxiety/panic -Increased need for physical stimulation -Alterations in sensory perception Interventions for Sensory Deprivation: Promote function of existing senses: glasses on, hearing aids in, expose to a variety of textures or colours, announce when entering room. Ensure stimulation is meaningful for patient: appropriate lighting, reading material, large print, audio books, watch, clock, calendars, pictures, TV, radio, cards, mobiles, posters, music, pets, newspaper, etc. Encourage visitors. Provide Meaningful conversation: communication boards for aphasic (lack of ability to communicate) clients, speak slowly, repeat as needed, encourage client to talk about family, friends, etc. Reorient confused patients to person, time, and place. Support, including significant others. 3. Sensory Overload: more sensory stimulation in a given time than one can tolerate. Brain cannot respond appropriately to stimuli OR may ignore stimuli. Sensory overload disrupts mechanism for information processing. Person can no longer make sense of environment: racing thoughts, scattered attention, restlessness, combative, anxiety, panic, confusion, hallucinations, disorientation, aggression, sleep loss= sleep deprivation= psychosis. Causes of Sensory Overload: Increase in internal stimuli: pain, IV lines, catheters. Increase in external stimuli: hospital environment, strangers, noises, lighting, machine, alarms, procedures. Even “comforting actions” can combine with other stimuli & can lead to overload. Interventions for sensory overload: block or reduce stimuli (dark glasses, drapes, ear plugs), minimize unnecessary lighting, noise, alarms, and other distractions. Control pain/nausea, eliminate odour, speak in a low tone/unhurried manner. Cluster care: carry out several nursing tasks at one time to create blocks of resting time. Factors Affecting Sensory Function: Age: Very young- immature NS Late adult- decreased sensory function, increased chronic diseases, medications. Vision: presbyopia, reduced visual fields, increased glare, reduced night vision Reduced colour discrimination- easiest to see: reds, oranges, and yellows. Hearing: hearing low pitch sounds the best, difficulty hearing conversation over background noises, sounds most difficult to discriminate: Z, T, F, G, S, SH, K. Taste/Smell: diminished sensory input, results in reduced desire to eat & drink. Danger: can’t smell bad food, smoke, gas leak, etc. Proprioceptive: decreased sensitivity to pain, pressure, and temperature. Quality of stimuli: needs to be meaningful to the person: pets, pictures, music, TV, calendar, clock. Quantity of stimuli: excess leads to Sensory Overload Insufficient leads to Sensory Deprivation Social Interactions & Family Factors: needed by everyone, family visits reduce sense of isolation. Environmental Factors: work and play environments- contain hazards that can damage senses. Loud noises, repetitive motions, dangerous chemicals, etc. Nursing Diagnosis: -impaired verbal communication -social isolation -risk for injury -disturbed sensory perception -situational low self-esteem Goals & Outcome: -client will demonstrate technique for cleaning hearing aid within 1 week. -client will use appropriate communication skills within 2 weeks. Setting priorities & continuity of care. Preventing Sensory Loss: -Encourage screening for high-risk groups: screen for syphilis or rubella in pregnant women, screen for glaucoma if family history, test hearing if working in noisy environments. -Encourage regular check-ups: eyes, ears, other. -Education: potential sensory threats. See doctor often when pregnant, pre-mature babies have increased risk of damage to eyes, ears, nervous system. -Work and play safely: avoid loud music, safety with ear buds, earmuffs to block loud sounds, hot water temperatures, eye shields, helmets, sunglasses. Visual Interventions: use of colour contrasts- red, orange yellow. Clock method for food plating. Tactile Interventions: usually impairment is over limited portion of the body, thus stimulate the unaffected portions (if ok with patient). For example, brush hair, massage back or feet, touching arms or shoulders. -Provide touch therapy -Turn and reposition patient q2hrs or sooner -Avoid excessive stimuli for hyperaesthetic (excessive sensitivity of skin or sense in a particular area) patient