sensory Flashcards
mechanoreceptors
receptors that detect pressure/vibration
ex: hair cells in the cochlear for hearing, equilibrium and balance
thermal receptors
temp variations
photoreceptors
in the eye (rods and cones)
chemoreceptors
taste buds after reception of stimuli
first step of sensation
Reception/activation of sensory receptors in the stimuli from nerve endings in the skin and inside the body.
The receptor converts the stimulius to nerve impulse and transmits the impulse to CNS
What is perception of stimuli?
Perception = to interpret the impulse from the receptors and give them meaning.
nerve impulses travel along the spinal cord and brain to specific locations in the brain.
The person becomes aware of the stimulius, recieves the information, adn interprets the sensation.
What is arousal mechanism?
Response to the sensation from the activation of the reticular activating system (RAS): mediates the endrocrine system, autonmic nervous system, consciousness, and alertness located in the brainstem.
Cataracts
A lens opacity (nontransparency) that impairs vision.
The proteins in the lens will deterioate and clump together to thicken and harden creating the opacity obstructing the light into the retina.
Cataracts - Risk factors
- old age: common
- trauma
- UV light
- Toxins
- corticosteroids
- severe myopia
- Fam History
- Diabetes
Cataracts - S/S
- painless gradual loss of vision
- complain of blurry/double vision
- pupil appears white/gray: advanced
- absent red reflex
Cataracts Dx
- physical examination
- visual acuity test
Cataract Treatment
Surgical removal of cataract
Cataract - post surgery care
- Eye drops: antibiotic, steroid, NSAIDs several times a day. maintain a strict regimen for those.
- wear dark sunglasses when going outside.
- Avoid activities IOP: bending at the waist, sneezing, coughing, blowing nose, do not lift >10lbs, aviod straining w/ bowel movements
- Vision should return approx 4-6 weeks.
Glaucoma
an eye disorder that damages the optic nerve and causes an increase in IOP.
open angle glaucoma
- more common.
- caused by aquaeous humor overproduction/decrease in outflow.
- Either of these causes gradual increase of intraolcular pressure
closed angle glaucoma
- less common
- caused by forward displacement of the iris
- the iris bulges forward and closes the angle completely between the iris and the cornea
- causes aqueous humor outflow to be blocked completely!
- results in rapid increase in IOP
Glaucoma risk factors
- aging
- genetics
- DM
- HTN
- eye trauma
- infection
S/S open angle glaucoma
- loss of peripheral vision
- ## mild aching in eyes/HA
S/S closed angle glaucoma
Emergency!
- severe eye pain
- N/V
- halos around lights
- ocular erythema - eye redness
- blurred vision
Glaucoma Dx
- tonometry: measures pts IOP
- normal IOP is 10-21mmhg
Glaucoma treatment
- Mannitol: osmotic diuretic which rapidly brings down IOP : closed angle glaucoma
- eye drops: open angle glaucoma for decreasing aqueous humor production or improving aqueous humor outflow.
macular degeneration
deterioration of the macula - part of the retina at the back of the eye
-results in central loss of vision
dry macular degeneration
more common
- tiny clumps of protein called drusen, that grow under the macula and cause that macular to become thinner adn dry out.
- slow onset
wet macular degeneration
- abnormal blood vessels that grow under the retina and leak blood/fluid into the macula causing scarring.
- less common
- faster onset
Dry macular degeneration TX
- No cure
Wet Macular Degeneration TX
- photodynamic therapy/ laser to seal off the blood vessels that are leaking
Macular degeneration teaching
- smoking cessation
- wear gunglasses
- follow up care with their eye PCP
- make home modifications: safety
loss of central vision
Macular degeneration assessment
decline in central vision
blurred vision + distortion
retinal detatchment
separation from the retina from the underlying epitheium
patho:
virteous humor that builds up behind the retina and pushes the retina away from the back of the eye and causes it to detatch
Retinal detachment: risk factors
- aging
- injury
- family history
- previous intraocular surgery
- ocular tumors
Retinal detachment S/S
- may complain of floaters
- flashing lights
- ## a curtain being drawn over their visual field
Retinal detachment TX
- emergency surgery to repair detatched retina
retinal detatchment surgery teaching
- restict head movement before surgery
- avoid activites that increase IOP
- report pain/nausea
Meriere’s disease
- inner ear disorder that causes issues with hearing and balance.
- exact cause is unknown.
- results in accumulation of endolymphatic fluid in the inner ear
Meriere’s disease S/S
- tinnitis = ringing in the ears
- unilateral sensoneural hearing loss
- vertigo = spinning sensation
- vomiting/balance issues
Meriere’s disease risk factors
- genetics
- infection
- otoxic medicatons (lasix)
Meriere’s diseaseTX
- No Cure. Provide supportive care.
- medications:
antihistamines
diuretics
antiemetics
-procedures:
labrynthectomy - will result in complete hearing loss on affected side.
Meriere’s disease Pt teaching
- advise pt to avoid caffiene, smoking and alcohol
- restrict salt intake
- distribute their fluid intake evenly throughout the day
Sensory overload S/S
- increased HR, BP, and breathing
- anxiety
-fear
-restlessness - irritibility
- covering eyes + ears
- tantrums in children
Sensory Deprivation S/S
- confusion
- drowsiness
- depression
- irritiabiltiy
- hallucinations
- illusion
- delusions
damage to the R hemispehere of the brain
affects functional communication, problem solving, memory, and reasoning.
homonymous hemianopsia
a field loss deficit in the same halves of a visual field in each eye
from a tumor, stroke, or TBI
homonymous hemianopsia example
An injury to the R side of the brain will cause loss in left half of both eyes
an injury to the L side of the brain will result in loss of vision in the R half of each eye.
R hemisphere syndrome w/ L homonymous hemianopia
- oritented yet impulsive
- struggle w/ organization
- speech is slow
- L sided neglect: L side of the world does not exist
Sensory overload interventions
- optimal pain management
- silencing non essential alarms
- clustering care activities
- resetting her internal clock: promoting sleep/wake cycles
Sensory deprivation interventions
- increasing interactions w/ visitors or chaplain
- open windows
- provide music, videos, crosswords
- providing in participation in care
- distraction activities: folding towels
Management of perceptual alterations
- reorienting to the external enviroment
- remind them that they are in the hospital and they are safe
- providing reassurance
- decreasing anxiety
- using simple commands
