Neurosensory Flashcards
Alert
Follows commands in a timely fashion
Lethargic
Appears drowsy, easily drifts off to sleep
Stuporous
Requires vigorous stimulation before responding
Comatose
Doesn’t respond to verbal or painful stimuli
Obtunded
Having diminished arousal and awareness, often as the result of intoxication, metabolic illness, infection, or neurological catastrophe
Semi-Comatose
State of drowsiness and inaction, in which more than ordinary stimulation may be required to evoke a response.
Syncope
A brief loss of consciousness caused by inadequate blood flow to the brain
Nystagmus
Involuntary, rapid, rhythmic movement (horizontal, vertical, rotatory, or mixed, i.e., of two types) of the eyeball
Flaccid
Weak, lax, or soft; applied especially to muscles
Dysphagia
Difficulty swallowing
Expressive Aphasia
Cannot communicate through speech, writing, or signs
Receptive Aphasia
Cannot receive or interpret verbal/non-verbal messages
Paresthesias/Neuropathy
An abnormal prickly, burning, or tingling sensation caused by nerve injury/Any disease of the nerves
4 Components of the Neurosensory Experience and the role of the Reticular Activating System
Reception, Perception/RAS, Arousal Mechanism, Responding to Sensations
- Reception
Process of receiving stimuli from nerve endings in the skin and inside the body
Reception:
Receptors convert stimuli to a ____ ______ and then transmits them along ____ ____ to the _____.
Nerve impulse; sensory neurons; Central Nervous System
Adaptation
Receptors responses to stimuli decline over time
Sensory Receptors: Mechanoreceptors
Skin and hair; detect touch, pressure, and vibrations
Sensory Receptors: Hair
- Hearing
- Cochlea= sound waves
- Vestibular Apparatus= acceleration of body and position of head
Sensory Receptors: Thermoreceptors
Skin; detect temperature
Sensory Receptors: Proprioceptors
Skin, muscles, tendons, ligaments, joint capsules; coordinate input and allow us to sense body position in space (proprioception)
Sensory Receptors: Photoreceptors
Retina; detect visible light
Sensory Receptors: Chemoreceptors
Taste buds; detect taste
Sensory Receptors: Olfactory receptors
Epithelium of nasal cavity; detect smell
- Perception
Ability to interpret impulses and give meaning to stimuli
• after impulses are sent to the CNS, they are then relayed to specialized locations in the brain where perception and awareness of the stimuli occurs
Perception requires functioning of the:
Sensory receptors, reticular activating system (RAS), neural pathways, and the brain
Factors that affect Perception of a stimulus
- Location (of receptors and pathway activated)
- Number (of receptors activated)
- Frequency (of action potentials generated [vary according to intensity of stimulus])
- Changes (in location, number, and frequency)
- Past experiences, knowledge, attitude, etc.
Reticular Activating System
Controls consciousness and alertness
• Neurons in the RAS make connections between the thalamus, spinal cord, cerebral cortex, and cerebellum –> relay visual, auditory, and other stimuli –> keep us alert, awake, and observant
• Anesthesia, opioids, sedatives, and other drugs depress the RAS along with dark rooms and quiet environments
• Regulates sleep
- Arousal Mechanism
see RAS
• Brain can adapt to constant stimuli, so to maintain arousal, variation in stimuli is required
- Responding to Sensation
• Brain sends impulses along motor pathways--> evokes response • Response to a stimulus is based on: Intensity Contrast Adaptation Previous Experience
Stimulus Response: Intensity
Excites more receptors –> stronger response
i.e. Bright light= shielding, squinting vs. dim light= little response
Stimulus Response: Contrast
Being outside in freezing cold windy weather and then entering a garage that blocks the wind, or then entering a room with a fireplace thats burring hot
Stimulus Response: Adaptation
Becoming accustomed to a stimuli, “tuning it out”
Stimulus Response: Previous Experience
•Affects ongoing responses to same stimulus in future
ex. Patient scrunching eyes before an injection (memory of a prior negative experience)
Factors that Affect Neurosensory Function: Developmental
Adults/Older Adults: Older adults have slower reflexes and delayed response to stimuli; structural changes in the eye and ear; sensory decline can cause depression, hallucinations, social isolation, withdrawal, etc.
Sensory Changes with Aging: Vision
- Decreased peripheral vision and tear production
- Vitreous humor thins (floaters appear)
- Lens discolors and is opaque/pupil shrinks= less light= limited vision
- Lens is less flexible/cannot focus on near objects
- Ciliary body contracts/lens thickens= lost visual acuity, decreased accommodation to distance and sudden changes in illumination/decreased night vision
Sensory Changes with Aging: Hearing
- Cerumen dries/solidifies= hearing loss
- Scarring
- Presbycusis (loss of high-frequency sounds) and decreased speech discrimination
Sensory Changes with Aging: Taste
- Taste buds atrophy and lessen= less tasting ability (esp. sweet)
- Drier mouth can alter taste
Sensory Changes with Aging: Smell
• Atrophy/loss of olfactory neurons= decreased ability to perceive smell (can also alter sense of taste)
Factors Affecting Neurosensory Functioning: Culture
Affects the nature, type, and amount of interaction and stimulation a person is comfortable with
Factors Affecting Neurosensory Functioning: Illness and Medications
- Illness: Neurologic diseases (i.e. MS) delay transmission of nerve impulses; Circulation impairment (i.e. atherosclerosis) affects sensory receptors/brain –> alter perception and response; Diseases can affect specific sensory organs (diabetic retinopathy=blindness)
- Medications: Aspirin and Lasix (furosemide) can become ototoxic and damage the auditory nerve; CNS depressants (opioids and sedatives) blunt perception/reception of stimuli
Factors Affecting Neurosensory Functioning: Stress
Stress= stimulation (i.e. running a marathon); can be too much stimulation and lead to sensory overload
Factors Affecting Neurosensory Functioning: Lifestyle and Personality
Clients are at risk for sensory alterations if previous level of stimuli doesn’t match current level; Loss of a partner, change in environment, and health problems can all lead to a change in stimuli
Assessment of a patient for Neurosensory Deficits: Nursing History
Usual and current mental status, prior sensory problems, use of sensory aides
Assessment of a patient for Neurosensory Deficits: Physical Assessment
6 senses (hearing, sight, touch, taste, smell, balance)
Assessment of a Patient for Neurosensory Deficits Info
Factors affecting, mental status, level of consciousness, recent changes, use of sensory aides, client’s environment, support network, and focused examination
Assessment: Level of Consciousness (LOC)
- Arousal and orientation
- Auditory stimuli (verbal communication or noise); Tactile stimuli (touch); Painful stimuli
- Alert, Lethargic, Stuporous, Comatose
Assessment: Orientation Status
- Time (year, date, time of day)
- Place (surroundings)
- Person (recognition of familiar people/self-identity)•
Assessment: Mental Status and Cognitive Function
Includes: behavior, appearance, response to stimuli, speech, memory, communication, and judgement
Observe for: clarity of thought, concentration, ability to perform abstract reasoning, appropriate material, and memory
Assessment: Mental Status and Cognitive Function
- Includes: behavior, appearance, response to stimuli, speech, memory, communication, and judgement
- Observe for: clarity of thought, concentration, ability to perform abstract reasoning, appropriate material, and memory
Assessment: Sensory Function
- Applying pressure to various parts of the body with patient’s eyes closed
- Usually upper/lower extremities (start with most peripheral i.e. foot–> leg)
Assessment: Pupillary Reaction/Accommodation
- Reaction: eye reaction, equality, speed
* Accommodation: pupil location and size
Sensory Deprivation
RAS depression caused by a lack of meaningful stimuli
Situations that cause Sensory Deprivation
Impaired sensory reception, impaired ability to transmit/process impulses, non stimulating environment, different cultures, restricted mobility, sensory deficits
Assessment: Client’s Environment/Support Network
- Compare patient’s usual personality and lifestyle to current environment; Assess effects of environment on sensory deficits (worsen/help compensate)
- Assume chores, provide comfort, increase stimulation and decrease sensory deprivation, reorient and calm confused persons from sensory alterations
Assessment: Pupillary Reaction/Accommodation
- Reaction: eye reaction, equality, speed
* Accommodation: pupil location and size
Sensory Deprivation: Definition and Signs
- RAS depression caused by a lack of meaningful stimuli
* Depression, delusional, hallucinations, preoccupied with somatic complaints
Sensory Overload
- External/internal stimuli exceeds higher level than what a person’s sensory system can effectively process
- Muscle tension, cant concentrate, disoriented, anxiety, decreased performance, restlessness
People at Risk for Sensory Overload
- Physical problems that stimulate CNS (hyperthyroidism)
- Medications/substances that stimulate CNS (caffeine, weight-loss pills)
- Neurological/Pyschiatric disorders–> cannot adapt to stimuli increase
- Hospitalized patients experience physical discomfort, anxiety, separation from family, unfamiliar environment
Nursing Interventions for Sensory Deprivation
*Provide stimulation; help patient perceive/interpret stimuli* • Visual/Auditory/Tactile stimulation • Media (inappropriate media--> sensory deprivation) • Social interaction • Minimizing anxiety and confusion • Facilitate communication • Collaboration • Self-stimulation • Pet Therapy
Sensory Deprivation: Causes and Effects of Visual Impairment
(CAROtMdRGSTDCNSMV) • Cataracts • Age-Related • Orbital trauma • Macular degeneration • Retinopathy (diabetic, hypertensive) • Glaucoma • Stroke • Trauma/disease of eye • CNS disorders • Microvascular problems *Affects ADL and limits mobility/interaction
Sensory Deprivation: Causes and Effects of Hearing Impairment
Injury/trauma to: • structures of the ear • nerves • brain *Creates safety hazards through decreased communication ability, social interaction, understanding
Nursing Interventions for Sensory Overload
- Control auditory/visual/olfactory stimuli
- Good TV/radio use
- Minimize stress
- Promote sleep
Sensory Deprivation: Causes and Effects of Hearing Impairment
Injury/trauma to: • structures of the ear • nerves • brain *Creates safety hazards through decreased communication ability, social interaction, understanding
Sensory Deprivation: Nursing Interventions for Visual Impairments
Client with sight: • Clean eyeglasses • Soft/diffuse light, sunglasses when outside • Large print Client with severely limited sight: • Uncluttered environment • Self-care items within reach • Make staff aware • Offer arm on preferred side when walking • Books on tape or braille • Bed in low position
Sensory Deprivation: Nursing Interventions for Hearing Impairments
- Promote auditory functioning (hearing aides, cerumen impaction, captions)
- Improve communication (written instructions)
- Safety (@ home: blinking lights; @ hospital: limit background noise, call bell in reach)
Sensory Deprivation: Causes and Effects of Confusion
Interferes with ability to interpret stimuli
• Delirium: acute, reversible, caused by meds and physiologic (hypoxia, metabolic disorders, infections, sensory alterations) CHANGES IN LOC
• Dementia: chronic, progressive, caused by physical changes in brain NO CHANGES IN LOC
Sensory Deprivation: Nursing Interventions for Confusion
- Promote orientation
- Simple communication
- Reduce anxiety
- Safety
- Continuity of care
Sensory Deprivation: Nursing Interventions for Unresponsive/Unconscious
- Involve/teach patient’s support network
- Incorporate touch
- Safety (bed in low, side rails up when not at bedside, eye care if eyes not closed, oral care)
Seizure
• Abrupt onset of disturbances in electrical activity in the brain; Neurons fire abnormally
• Rhythmic jerking, decreased LOC or loss of consciousness
*Incidence highest amongst:
-younger than 10 and older than 65
-males
Safety Precautions for Seizures
- Pad head, foot, and side rails of bed
- Keep side rails up when not at bedside
- Suctioning at bedside
- Suction after to prevent aspiration
- Dont open mouth or insert depressor/hand
