sensory disorders Flashcards
1
Q
are the 4 eye functions that provides clear images and vision (4)
A
- refraction
- pupillary constriction
- accommodation
- convergence
2
Q
refraction
A
bends light rays from the outside into the eye through curved surfaces and refractive media and finally into the retina
3
Q
pupillary constriction
A
- constriction and dilation control the amount of light that enters the eyes
4
Q
accommodation
A
allows the healthy eye to focus images sharply on the retina whether the image is close to the eye or distant
5
Q
convergence
A
- ability to turn both eyes inward toward the nose at the same time
6
Q
coordinated eye movements ensure?
A
- both eyes receive an image at the same time so only a single image is seen
7
Q
muscles around the eye are innervated by
A
cranial nerves 3 (oculomotor), 6 (trochlear), and 11 (abducens)
8
Q
the optic nerve (CN 2) is
A
nerve of sight, connecting the optic disc to the brain
9
Q
the trigeminal nerve (CN 5)
A
stimulates the blink reflex when the cornea is touched
10
Q
the facial nerve (CN 7) innvervates
A
lacrimal glands and muscles for lid closure
11
Q
assessment of the the eyes include: (2)
A
- assess muscle function (eyes will NOT turn to a particular position if the muscle is weak or if the controlling nerve is affected)
- vision testing: visual acuity tests to measure both distance (snellen eye chart) and near vision (rosenbaum pocket vision screener) -> findings recorded as a comparision between what the patient can read at 20 feet and the distance that a person with normal vision can read that the same time
ex:
- 20/50 means that the patient sees at 20 feet from the chart what a healthy eye sees at 50 feet
12
Q
age related changes for vision (5)
A
1) arcus senilis
2) presbyopia
3) ectropion
4) clarity and shape of the cornea change with age (cornea flattens, curve of its surface becomes irregular, this change worsens with astigmatism and blurred vision)
5) iris has less ability to dilate, which leads to difficulty in adapting to dark environments
13
Q
arcus senilis
A
an opaque, bluish white ring within the outer edge of the cornea, caused by fat deposits (will look like blue eyes)
14
Q
presbyopia
A
- near objects, especially reading material must be placed farther from the eye to be seen clearly (bifocals)
15
Q
ectropion
A
- the lower eyelid may relax and fall away from the eye, leading to dry eye manifestations
16
Q
refraction
A
bending of light rays for the ability of the eye to focus images on the retina and depends on the length of the eye from front to back and the refractive power of the lens system
17
Q
types of refraction (4)
A
1) emmetropia
2) hyperopia
3) myopia
4) astigmatism
18
Q
emmetropia
A
perfect refection of the eye in which light rays from a distant source are focused into a sharp image on the retina
19
Q
presbyopia (what, as a result, begins in)
A
age related problem in which the lens loses its elastricity and is less able to change shape to focus the eye for close work
- as a result, images fall behind the retina (hyperopia)
- begins in people in their 40s
20
Q
hyperopia (farsightedness) (what, s/sx, tx)
A
- occurs when the eye does not refract light enough, as a result, images actually converge behind the retina
- s/sx: distant vision is normal, near vision is POOR
- tx: corrected with a convex lens in eyeglasses or contact lenses
tips: difficulty driving/reading, can see far away, reading glasses
21
Q
myopia (nearsightedness) (what, s/sx, tx)
A
- occurs when the eye over bends the light and images converge in front of the retina
- s/sx: near vision is normal, distance vision is POOR
- tx: corrected with a biconcave lens in eyeglasses or contact lenses (LASIK)
22
Q
astigmatism (3)
A
- refractive error caused by unevenly curved surfaces on or in the eye, especially of the cornea
- these uneven surfaces distort vision
- d/t light rays are not refracted equally in all directions, the image does not focus on the retina
23
Q
refractive errors nursing interventions (3)
A
- eyeglasses
- contact lenses
- last in-situ kertamileusis (LASIK) surgery or photorefractive keratectomy (PRK): both procedures correct nearsightedness, farsightedness, and astigmatism, powerful laser pulses reshape the deep corneal layers
extra:
- side effects: halos, glares (decreased visual acuity)
- meds: corticosteroids, NSAIDs, antibiotics
24
Q
blindess
A
having best corrected visual acuity that can range from 20/400 to no light perception
- legally defined by visual acuity with corrective lenses is 20/200 or less in the better eye or if the visual field is 20 degrees or less
- blindness can occur in one or both eyes
25
blindness nursing interventions (5)
- communication
- safety
- ambulation
- self care
- support
26
glaucoma
group of eye disorders resulting in increased OP (intraocular pressure)
- tissues damage starts in the periphery and moves inward toward the fovea centralis
27
IOP
normal IOP requires a balance between production and outflow of aqueous humor
- if IOP becomes too high, the extra pressure compresses retinal blood vessels and photoreceptors and their synapsing nerve fibers
- this compression results in poorly oxygenated photoreceptors and nerve fibers
- these sensitive nerve tissues become ischemic and die. when too many have died, vision is lost permanently
28
what is normal IOP when aqeuous fluid production and drainage are in balance
10-21 mmhg
29
primary open angle glaucoma (POAG) (3)
- wide angle glaucoma
- most common form of primary glaucoma, outflow of aqeuous humor through the chamber angle is reduced
- usually affects both eyes and has no manifestations in the early stages
30
primary angle closure glausoma (PACG) (3)
- acute glaucoma or narrow angle glaucoma
- forward displacement of the iris, which presses against the cornea and closes the chamber angle, suddenly preventing outflow of aqueous humor
- sudden onset, EMERGENCY
31
glaucoma s/sx angle closure glaucoma (6)
- severe pain in the eye or forehead
- redness
- decreased or blurred vision
- seeing halos or rainbows
- headache
- N/V
32
glaucoma s/sx open angle glaucoma (3)
- early manifestations: none, painless
- loss of peripheral vision
- halos
33
glaucoma nursing interventions (pharm (5), surgery (2))
pharm:
- prostaglandins agonists drugs: reduce IOP by increasing aqueous humor outflow
- adrenergic agonists, beta adrenergic blockers: reduce IOP by limiting the production of aqueous humor and by dilating the pupil
- cholinergic agonists: reduce IOP by increasing the outflow of the aqueous humor
- carbonic anhydrase inhibitors: directly and strongly inhibit production of aqueous humor
- systemic osmotic drugs may be given for angle closure glaucoma to rapidly reduce IOP (oral glycerin, IV mannitol)
surgery:
- shunts, implants (helps aqueous humor to flow)
34
cataract (what, s/sx (4))
lens opacity that distorts the image
- both eyes may have cataracts, but the rate of progression in each eye is different
s/sx:
- early manifestations: slightly blurred vision, decreased color perception
- blurred vision
- double vision
- opacity: prevents light from producing images
35
cataracts nursing interventions (3, post surgery (4))
- prevention: smoking cessation, weight reduction, optimal blood sugar control, sunglasses, etc.
- promote safety and independence
- surgery when symptoms interfere with ADLs (cataract removal surgery -> outpt.)
post surgery:
- educate on the importance of close adherence to the eye drop regimen after surgery
- wear a light eye patch at night to prevent accidental rubbing
- assess for signs of infection
- remind the patient to avoid activities that might increase IOP
36
macular degeneration
deterioration of the macula (area of central vision)l with the most common type being the age related macular degeneration (AMD)
37
macular degeneration types (2)
1) dry AMD: most common, caused by gradual blockage of retinal capillaries, allowing retinal cells in the macula to become ischemic and necrotic
2) wet AMD: growth of new blood vessels in the macula, which have thin walls and leak blood and fluid
38
macular degeneration s/sx (4)
- central vision declines
- mild blurring
- distortion
- eventual loss of all central vision
39
macular degeneration nursing interventions (3)
1) prevention: key or slow the progression of vision loss
- dietary intake of antioxidants, vitamin B12, vitamin E, carotenoids
- control HTN (increased IOP, increase microvascular damage)
- stop smoking
2) supportive care
3) wet AMD
- laser therapy to seal the leaking blood vessels can limit the extent of the damage
- ocular injections with the vascular endothelial growth factor inhibitors (VEGFIs), such as bevacizumad (avastin) or ranibizumab (lucentis)
40
retinal disorders (2) s/sx (5)
1) retinal tear
2) retinal detachment
s/sx:
- sudden onset
- painless
- bright flashes of light (photopsia)
- floating dark spots (floaters)
- shade or curtain coming across the vision
41
retinal tear
- more jagged and irregularly shaped break in the retina
42
retinal detachment
- separation of the retina from the epithelium, classified by the type and cause of their development
- MEDICAL EMERGENCY
43
retinal disorders nursing interventions (4)
- education
- supportive care
- retinal hole or tear: defect may be closed or sealed with surgery
- retinal detachment: surgical repair via scleral buckling, to place the retina in contact with the underlying structures (put back where it's supposed to be)
44
conjunctivitis
- inflammation with or without infection of the conjunctiva
- occurs from exposure to allergens or irritants
- often called "pink eye", it is a common eye disease, especially in children
45
conjunctivitis s/sx (7)
- a gritty feeling in one or both eyes
- itching or burning sensation in one or both eyes
- excessive tearing
- discharge from one or both eyes
- swollen eyelids
- pink discoloration to the whites of one or both eyes
- increased sensitivity to light
46
allergic conjunctivitis
- occurs more commonly among people who already have seasonal allergies, they develop these symptoms when they come into contact with a substance that triggers an allergic reaction in their eyes (bilateral)
47
allergic conjunctivitis s/sx (7)
- edema
- sensation of burning
- a "bloodshot" eye appearance
- excessive tears/watery drainage
- extreme itching
- severe photophobia
- don't touch eye/mucous membrane
48
allergic conjunctivitis treatment (4)
- cool compresses and artificial tears sometimes relieve discomfort in mild cases
- NSAIDs and antihistamines
- vasoconstrictor and corticosteroid eye drops
- instruct patients to avoid using makeup near the eye until all symptoms are gone
49
viral conjunctivitis
- most commonly caused by contagious viruses associated with the common cold
- since tears drain into the nasal passageway, forceful nose blowing can cause a virus to move from your respiratory system to your eyes
50
viral conjunctivitis s/sx (3)
- tearing/drainage, itchiness, redness, and light sensitivity
- recent or current upper respiratory infection
- possibly preauricular lymphadenopathy (infront of ears)
51
viral conjunctivitis treatment (2)
- symptoms can often be relieved with clean cool compresses and artificial tear solution
- topical steroid drops may be prescribed to reduce the discomfort from inflammation in severe cases
52
bacterial conjunctivitis
infection most often caused by staphylococcal or streptococcal bacteria from your own skin or respiratory system
53
bacterial conjunctivitis s/sx (3)
- blood vessel dilation, redness, edema, burning, and discharge
- discharge is watery at first and then becomes thicker, with shreds of mucus
- crusting in the morning
54
bacterial conjunctivitis treatment (3)
- cultures of the drainage may be obtained to identify the organism
- ophthalmic antibiotics are prescribed to eliminate the infection
- teach the patient the importance of preventing the spread of the infection to other eye or to other people
tip: may not see cultures as often unless other issues, teach kids to avoid touching eyes (bacteria spreads easily)
1) hand hygiene
2) clean face towels
3) don't share items
55
trauma
foreign bodies, lacerations or penetrating trauma
56
trauma s/sx (5)
- feeling of something being in the eye (depends on severity/type)
- blurred vision
- pain
- tearing
- photophobia
57
trauma treatment (2, surgery)
- immobilize (do NOT apply a pressure patch to the affected eye -> paper cup to prevent spread)
- antibiotics
- surgery: remove foreign object in eye
58
the ear has 3 important divisions important to hearing:
external ear (pinna, ear lobe, canal)
middle ear (tympanic membrane, osciles)
inner ear (labrinth, CN 8th)
59
auditory sensory perception (5)
main function of the ear and occurs when sound is delivered through the air to the external ear canal
- sound waves strike the movable eardrum, creating vibrations
- eardrum is connected to the first bony ossicle, which allows the sound wave vibrations to be transferred from the eardrum to the malleus, incus, stapes
- receptors at the cochlea transduce (change) the vibrations into action potentials (conduced to the brain as nerve impulses by the cochlear portion of the 8th CN (auditory) nerve)
- nerve impulses are processed and interpreted as sound by the brain in the auditory cortex of the temporal lobe (brain)
60
age related changes ear (7)
- pinna becomes elongated because of loss of subcutaneous tissues and decreased elasticity
- hair in the canal becomes coarser and longer, esp. in men
- cerumen is drier and impacts more easily, reducing hearing function
- tympanic membrane loses elasticity and may appear dull and retracted
- hearing acuity decreases
- ability to hear high frequency sounds is lost first (older adults may have particular problems hearing the "f,s,sh,and pa"
- presbycusis
61
presbycusis (3)
- hearing loss that occurs with aging
- caused by degeneration of cochlear nerve cells, loss of elasticity of the basilar membrane, or a decreased blood supply to the inner ear
- shell structure of ear
62
assessment (3)/examination of ear (3)
- assess: vertigo, tinnitus, any medications
- examination: inspection, palpation, otoscope
otoscope: hold the otoscope in your dominant hand, and gently pull the pinna up and back with your other hand to straighten the canal
63
normal hearing (weber, rinne)
weber: sound is heard equally in both ears
rinne: air conduction is audible longer than bone conduction in both ears
64
conductive hearing loss (weber, rinne)
weber: sound is heard best in affected ear (hearing loss)
rinne: sound is heard as long or longer in affected ear (hearing loss)
65
sensorineural hearing loss (weber, rinne)
weber: sound is heard best in normal hearing ear
rinne: air conduction is audible longer than bone conduction in affected ear
66
cerumen impaction (what 2)
- cerumen (earwax): most common cause of impacted canal
- becomes impacted as a result of foreign bodies that can enter or be placed in the external ear canal, such as vegetables, beads, pencil erasers, and insects (esp. peds)
67
cerumen impaction s/sx (4)
- otalgia (ear pain)
- hearing loss
- itching
- dizziness
68
cerumen impaction nursing interventions (4)
- watchful waiting (self resolved)
- manual irrigation (water solution)
- manual removal
- ceruminolytics (meds remove ear wax)
69
external otitis
inflammation of the external auditory canal and is painful condition caused when irritating or infective agents come into contact with the skin of the external ear
- occurs more often in hot, humid environments, especially in the summer, and "swimmer's ear" because it occurs most often in people involved in water sports
70
external otitis s/sx (3)
- redness and tender to touch or movement
- mild itching
- swelling of the ear canal can lead to temporary hearing loss from obstruction
71
external otitis nursing interventions (3, pharm (4))
- applying heat to the ear for 20 minutes 3 times a day
- teach patient that minimizing head movements reduces pain
- avoid any water sport activity for approximately 7-10 days to allow the canal to heal (summer cap, ear plugs)
pharm:
- topical antibiotic drops
- steroid therapies
- oral or IV antibiotics are used in severe cases
- analgesics
72
external otitis ear drops application (6)
- remove and discard any ear packing
- irrigate the ear if the eardrum is intact
- place the bottle of eardrops in a bowel of warm water for 5 minutes
- tilt the patient's head and place the drops in the ear
- move the head back and forth 5 times
- insert a cotton ball into the opening of the ear to act as packing
73
otitis media
infecting agent in the middle ear causes inflammatino of the mucosa, leading to swelling and irritation of the ossicles within the middle ear, followed by purulent inflammatory exudate (drainage)
- pathogens enter the middle ear after eustachian tube dysfunction -> caused by obstruction related to upper respiratory infections, inflammation of surrounding structures, or allergic reactions
74
otitis media s/sx (5)
- fever, ear pain, otalgia
- reduced hearing
- tinnitus, dizziness
- headache
- nausea/vomiting
75
otitis media nursing interventions (supportive care, pharm, surgery)
1) supportive care:
- quiet environment
- low heat application
- reduce head movements
2) pharm:
- antibiotics PO
- analgesics (pain)
- antipyretic (fever)
3) surgery
- ear tubes to help balance pressure from middle to external ear (common)
76
tinnitus
continuous ringing or noise perception in the ear, common ear problem that can occur in one or both ears
77
tinnitus s/sx (1)
- mild ringing to loud roaring
78
tinnitus contributing factors (5)
- age
- sclerosis of the ossicles
- underlying disorders
- drugs (lasix, vanco, abx)
- exposure to loud noise
79
tinnitus nursing interventions (supportive care, pharm (2))
1) supportive care:
- decrease background noise
- ear mold hearing aids
- support groups
2) pharm:
- mirapex (dopamine agonist) -> parkinson's disease
- not indicated by FDA
lasix: otoxicity
80
vertigo
sense of whirling or turning in space, whether it be the person or the surroundings
81
dizziness (2)
- aka lightheadedness
- disturbed sense of a person's relationship to space
82
vertigo/dizziness s/sx (5)
- nausea, vomiting
- falling
- nystagmus
- hearing loss
- tinnitus
83
vertigo/dizziness nursing interventions (supportive care, pharm (4))
1) supportive care:
- restrict head motion and change position slowly
2)pharm:
- dimenhydrainte OTC (antihistamines - N/V)
- meclizine (antihistamines)
- scopolamine (anticholinergics -> antagonistic histamine response)
- diazepam (benzo)
extra:
- side effects: dry mouth, dizziness, urinary retention, drowsiness, avoid driving
84
meniere's disease
abnormality in inner ear fluid balance caused by a malabsorption in the endolymphatic sac or a blockage in the endolymphatic duct
85
meniere's disease 3 features
- tinnitus
- one sided sensorineural auditory sensory perception loss
- vertigo, occuring in attacks that can last for several days
86
meniere's disease nursing interventions (supportive care, pharm (4), surgery (3))
1) supportive care:
- move head slowly to prevent worsening of the vertigo
- nutrition and lifestyle changes can reduce the amount of endolymphatic fluid
2) pharm:
- mild diuretics to relieve symptoms by lowering the pressure of the ear
- antihistamines to shorten attacks
- benzodiapepines in acute instances to help control vertigo
- antiemetics to control N/V
3) surgery:
- shunts
- vestibular
- vertigo sx are debilitating
87
hearing loss/deafness
partial or complete loss of the ability to hear
88
deafness s/sx (7)
- tinnitus
- increasing inability to hear when in a group
- a need to turn up the volume of the tv
- can trigger changes in attitude
- inability to communicate
- unawareness of surroundings
- the ability to hear high frequency consonants (esp. s,sh,f,th,ch sounds) is lost first
89
heading loss/deafness diagnostic labs/tests (6)
- labs: none
tests:
- weber test
- rinne test
- audiometry
- XR
- CT
- MRI
90
hearing loss nursing interventions (4)
1) protective measures: ear muffler, avoiding ototoxicity meds
2) correct underlying problem
3) assistive devices: portable amplifiers, hearing aids, learning lip reading/sign lang.
4) surgery:
- cochlear implants
