EXAM 4 NUR 265 very detailed lecture notes PDF

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Detailed notes for chapter 46 eye & vision including charts/graphs, colorful and very helpful...

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Chapter 46 Assessment of the Eye & Vision A & P Review Refractive structures and media (each structure bends (refracts) the light waves to focus images on the retina, together they are considered “refracting media”) o

cornea, aqueous humor (in front of pupil), lens, vitreous body, IOP

Aqueous Humor -

Clear, watery fluid; fills anterior and posterior chambers of the eye, produced by ciliary process Drains into the blood to maintain (IOP) (drains in and out when we need it)

Lens and Cataracts -

Lies behind iris, bends with light rays, transparent Curve of lens changes shape to adjust for far and near objects o With cataracts loses transparency → cloudy, opaque, or whitish color

Vitreous body -

Thick gel like, fills space between retina and lens, eye must remain shape of ball to maintain vision maintains the eyes shape→ if don’t have enough eye could collapse on self o BALANCE with aqueous humor in anterior segment of the eye to maintain pressure to keep eye inflated

Intraocular Pressure/ Glaucoma -

IOP LOW → collapse eyeball, prevents light from reaching back of eye (DEHYRATION) IOP HIGH= GLAUCOMA→ compression of capillaries, hypoxia, blindness o O2 being delivered to eye not able to get there, retina can’t get enough O2 o Eye must keep intraocular pressure → Dehydration could cause to collapse, medications as well

External structures → o o o o o

Eyelids (protect eyes to keep cornea moist) Canthus (two eyelids meet at the corner of eye) Conjunctivae (mucous membranes of the eye) lacrimal gland (upper outer of each orbit, PRODUCES TEARS) punctum (where tears drain) ▪ Apply pressure to punctum when doing eyedrops so doesn’t go systemic →specially eye drops that LOWER BP

Muscles (usually issues w muscles happen with children→ eyes turn inward; SOMETIMES WHEN PEOPLE ARE TIRED THIR EYE MUSCLES GET WEAK AND EYE GOES OPPOSITE DIRECTION), nerves, blood vessels Muscles, Nerves, and Blood Vessels (6 voluntary muscles rotate eye & coordinate movement) -

The muscles around eye are innervated by cranial nerves Optic Nerve (CN II) 2 – assess for vision o Sight Trigeminal nerve (CN V) 5 o Blink reflex when cornea is touched → cotton ball and touch cornea lightly “blink reflex – positive” Facial nerve (CN VII) 7 - Bell’s Palsy, inflamed, not working correctly o Lacrimal glands and muscles for lid closure, helps eye be able to open and close o Eye open for a long time could be damages ▪ Ophthalmic artery → oxygenated blood to eye

The four eye functions that provide clear images and vision are refraction, pupillary constriction, accommodation, and convergence. Refraction (how we see; bends light rays from the outside into the eye through curved surfaces and refractive media and finally to the retina) When people in their 40’s they get both hyperopia and myopia Emmetropia Hyperopia (farsightedness- see far away) Myopia (nearsightedness)

Astigmatism (hurts feel like sand in eye)

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The perfect refraction of the eye (PERFECT VISION) Occurs when the eye does not refract light enough (not enough light into eye) When the eye over refracts or overbends the light (too much light), BIGGER PUPILS Refractive error caused by unevenly curved surfaces on or in the eye, especially cornea → has to do with shape, elongated, egg shape, cornea misshaped - A lot of people can’t wear contacts/lenses

Surgery for Refractory Errors→ LASIK (far/near or both) o Complications of LASIK → infection, cornea clouding, chronic dry eye, refractive errors

Pupillary Constriction and dilation control the amount of light that enters the eye -

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Miosis (pupillary constriction) → check this with pen light, shine into eye it constricts (farsightedness) o Level of light ↑ either eye pupils should constrict, constriction depends on how much light is available and how well the retina can adapt to the light changes Mydriasis (pupillary dilation) → get done with eyes getting checked up (nearsightedness) o Mydriatic eye drops to see anterior of eye

Accommodation is the process of maintaining a clear visual image when the gaze is shifted from a distance to near object (at end of PERRLA) (allows the healthy eye to focus images sharply on the retina regardless if image is close or far) o o o

Assess for by having them gaze at point in room while looking at pupils, then ask to look at something close to see if pupil’s change Looking at something far away→ dilate Close up→ constrict (should both at the same time) ▪ HOW TO ASSESS→ hold finger about 18 cm from nose and move toward nose, eyes usually converge, and pupils constrict equally

Convergence is the ability to turn both eyes inward towards nose at same time (eyes get closer together when put object closer to face→ like go cross eyes) Age Related Structural Changes -

↓ eye muscle tone (can’t keep eye focused on a single object) Ectropion and dry eye (lower eyelid drooping, issue bc lower eyelid turns outward and eye dry’s→ issues w scratched cornea) Arcus senilis (fat deposits around eye, does not affect vision→ NOT ABNORMAL) Corneal changes (makes astigmatism worse) Changes in color of sclera (may have yellowish tent, not the best place to check for jaundice on older person) Less ability to dilate pupil (issue bc when we dilate pupil allow more light to come in, sunny outside and you come inside eyes want to dilate to let more light in bc darker inside) *RISK FOR FALLS BC DILATING SLOWER More light needed for reading (KNOW WHAT TO TEACH→ → more lighting) ↓ tears (cornea issues, use artificial tears)

Age Related Functional Changes -

Lens yellow (opaque color) Accommodation is gradually lost → have issue going from looking at something further to close; have delay in process Near point of vision ↑ (presbyopia) Color perception ↓ → blues, greens, violets (if do color test may not be able to see)

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IOP ↑ (already have issue w IOP, pushing on retinal blood vessels lead to blindness)

Health Promotion and Maintenance -

Risk for cataracts and cancer ↑ with exposure to UV rays (sun, tanning bed without eye protection) Vision can be affected by injury (work environments→ do they use eye protection in area w metal, WELDING) Eye infections can cause vision loss (NOTIFY PCP right away) o TEACH older to see PCP immediately when eye injury occurs of infection suspected Eye exams → OVER 40 EVERY YEAR

Patient History Age (does matter bc have been exposed to more sun) Gender (retinal detachments (MEN→ bc “high risk activity”), dry eyes) Occupation/leisure activities (eye protection)

Nutrition History

Family History/Genetic Risk

Vitamin A deficiency (dryness, keratomalacia, blindness)

Document (gender, relationship, age, and nature) → whether is was mother/father what age they got it

ENCOURAGE → Fruit that are bright colors → red/orange, and green vegetables

Retinal Blastoma (CHILDREN) → genetic, deadly, very close to the brain, usually one eye

Exophthalmos (protruding eye)sometimes people w ENDOCRINE – can dry out eyes Enophthalmos (sunken eye)

Timing (gradual or sudden)

Events surrounding injury/visual change Cancer in both eyes more genetic, anything with both organs is usually genetic

10 servings/day

Squinting, tilting head, closing one eye, symmetry, equal distance

Onset of visual problem

Both eyes or one

Systemic health problems (HTN, diabetes) / DRUGS 46.2

Assess EYE without touching patient

Current Health Problems

Scleral & Corneal Assessment

Pupillary Assessment

Corneal abrasions → use penlight, should be transparent/smooth

Anisocoria (difference in size) – very rare amount of people will have unequal pupils and its normal for them; but if someone says not normal for them then needs to be looked at

A lot of people who sleep in contacts or wore for a while may have corneal abrasion or scarring

Smaller in older adults – not dilating, so not letting enough light in Myopia – larger (near vision) Hyperopia – smaller (far vision)

Eyebrows/eyelashes – could have issues w reticulitis (eyelashes growing on one side/not other) (Ptosis → drooping of the eyelid → can have surgery for this), lesions, swelling

Variations of sclera color Assess blink reflexes

Normal diameter → 3-5 mm Car accident, HTN, injury to head Consensual responses → constriction of the left pupil when light is shined at the right Direct Response → eye you shine pen light in Indirect Response→ other eye response PERRLA Sluggish more than 1 second to constrict (drugs) Nonreactive, fixed (failed to move); stroke on R side of brain, may not be able to see in L eye → pupil dilated and FIXED in that position

Sudden or persistent loss of visual sensory perception within the past 48 hours, eye trauma, foreign body in eye, sudden ocular pain is EMERGENCY

How DRUGS affect eye → dryness, itching, foreign body sensation, redness, tearing, photophobia, development of cataracts and glaucoma Systemic Conditions/Disorders DM, HTN, Lupus, Sarcoidosis, thyroid problems, acquired immune deficiency syndrome, cardiac disease, multiple sclerosis, pregnancy

DRUGS Antihistamines, Decongestants, Antibiotics, Opioids, Anticholinergics, cholinergic agonist, adrenergic agonist (BETA BLOCKER), oral contraceptives, chemo agents, corticosteroids

*HOW to teach patients to give eyedrops 46.2 (REVIEW) Check eye drops like usual meds (strength, ex date, color, clarity), if using on both eyes each will have specific bottle, wash hands, remove cap from bottle, tilt head back, open eyes, look up at ceiling, using non dominant hand gently pull lower lid down against cheek (forming a small pocket), hold bottle like a pencil with tip pointing down (dominant hand), rest wrist holding bottle against mouth or upper lip, without touching any part of eye or lid squeeze release # drops prescribed, release lower lid & gently close eye, gently press and hold corner of eye near nose to close punctum off and prevent drug from becoming systemic, blot away and excess or tears w tissue, keep eye closed about 1 minute, place cap, store where prescribed, wash hands again

Vision Testing o

Visual acuity (near and far vision) → ▪ Snellen Chart (checking far/distant vision) ▪ Jaeger card or Rosenbaum Pocket Vision (near vision)- trouble reading •

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Hold chart 14 inches away and read covering one eye at time

▪ Screener Visual Field → (peripheral vision) ▪ Computer (perimetry) or confrontation test (see if you can see peripherally, come from sides) Extraocular muscle function → ▪ corneal light reflex – alignment of eyes ▪ 6 cardinal positions of gaze (3 positions one side, 3 on other) • These tests assess smoothness of eye movements and cranial nerves III, IV, VI Color Vision → Ishihara chart (number hidden in different colors)

What is 20/20 Vision (visual acuity) → assessing cranial nerve II Snellen Chart→ Patient stands 20 feet from chart cover one eye, then the other, then use both to see what line can see 20/20 – can see clearly at 20 feet away (normal acuity) – line 8 on Snellen chart o See the same line of letters at 20 feet that person w normal vision can see at 20 feet 20/40 → At 20 feet sees what a person with normal vision would see at 40 feet 20/200→ At 20 feet sees what a person with normal vision would see at 200 feet away o

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Diagnostic Tests -

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Labs → diagnose infections, antibiotics after culture Imaging → CT, MRI (NOT for metal in eye) Radioisotope scanning (tumors/lesions) US (If eyes open numb with anesthetic drops (LASIX surgery) o do NOT rub eyes after, so doesn’t go systemic Slit-lamp exam → magnifies anterior eye structures o Patient leans on chin rest, narrow bean (slit) light aimed so only segment of eye is brightly lightened, examiner can then locate position of abnormality in cornea, lens, anterior vitreous humor Corneal Staining → abrasion, trauma, scratches, foreign bodies, ulcers, etc o dye the scratches bright blue color→ remember it can go systemic so drink a lot of water URINE DARK GREEN/BLUE Tonometry → IOP measurement (10-21 mmHg)

Recommended everyone OVER 40 1X YEAR, in pt with HX of glaucoma 2X YEAR tells if you have GLAUCOMA & measured 2X a YEAR Goldman’s applanation tonometer with slit lamp used a lot of times in office (MOST COMMON) Tono-Pen used at home if they have glaucoma (need to check same time everyday to have best results) & used for patients unable to be positioned behind slit lamp Ophthalmoscopy – dark room, stand on same side of eye being examined, patient looks straight ahead at object, red reflex (red glare @ pupil) should be seen → if can’t see may have opacities or cataracts o Won’t be able to see red reflex in tumor/cancer or retinal blastoma o Doing this to visualize the internal structures (color, tangles, narrowing, lesions, bleeding) ▪ “maybe they’ve had high BP for a while and want to see if there is bleeding, what color blood vessels look like” o DON’T USE ON CONFUSED PATIENT BC ↑ RISK OF INJURY Fluorescein angiography (need a consent/invasive done by DR) → retinal circulation (diabetic retinopathy, retinal hemorrhage, macular degeneration) & intraocular tumors o Digital pictures o Mydriatic drops 1 HOUR BEFORE (cause pupil to dilate) o Warn patient stain may cause skin to be yellow several hours o Eliminate through urine → GREEN o Encourage pt to → drink plenty of fluids, skin will return normal, instruct to Wear sunglasses until pupils return to normal Electroretinography o Retina response to light stimulation, evaluates blood vessel changes from disease or drugs o o o o

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Chapter 47 Care of Patients with Eye & Vision Problems Cataracts Clouding and burning (opacity→ won’t be able to see a RED REFLEX) of the lens distort the image and color projected not the retina (retina is in the back of eye) As cataract matures, opacity makes it difficult to see the retina

Causes Age (can w birth of develop with age)

Cataract Post OP: Antibiotics given subconjunctivally Eye is unpatched

Most common >70 (depends on lifestyle they live)

Discharge usually occurs within 1-hour w dark glasses

Trauma, toxins

TEACH - Instill antibiotic-steroid eyedrops

Associated disease → DM, Hypoparathyroidism, Down syndrome, chronic sunlight exposure

Mild itching NORMAL → DON’T RUB

Visual acuity is restricted No pain or eye redness is associated with age-related cataracts Surgery if ADL’s are affected (cook, put makeup on)

PAIN INDICATED COMPLICATION (CALL DR) Reduce IOP, prevent infection, assess for bleeding

Complicated by other eye problems (glaucoma)

If patient has had cataract surgery immediately report any reduction of vision

Best vision → 4-6 weeks (teach not going to have clear vision right away) Report to DR→ sharp, sudden pain, bleeding, ↑ discharge and swelling, ↓ vision, flashes of light of floating shapes AVOID activities ↑ IOP (47-2) Review USE OF EYEDROPS (especially ones that lower of higher BP & could go systemic)

Glaucoma Group of ocular diseases resulting in increased IOP (loose peripheral vision IMPORTANT which extinguishes it → only see center part of picture→ from pressure on lens) Primary open- angle glaucoma (MOST COMMON)

Clinical Manifestations: Cupping and atrophy of the optic disc (must look on inside when dilate w ophthalmoscope); disc wider and deeper and turns white or gray Visual field measurement, periphery

NO KNOWN WAYS TO TX

PACG (acute glaucoma) “ANGLE-CLOSURE” → headache or brow brain, N, V, colored halo around lights, sudden blurred vision w ↓ light perception

BEST WAY TO PREVENT regular eye exams

Primary OPEN-ANGLE usually PAINLESS

Angle-closure glaucoma (EMERGENCY) → sudden sharp pain

Causes: PRIMARY (age, hereditary, central retinal vein occlusion) Associated (DM, HTN, severe myopia, retinal detachment) SECONDARY (uveitis, iritis, neurovascular disorders, trauma, ocular tumors, degenerative diseases, eye surgery)

Diagnostic Tests: Tonometry (normal 10-22 mmHg) OAG 22-32 ACG 30 or higher (usually higher) *REMEMBER PRESSURE CHANGES – TAKE IOP AT SAME TIME Perimetry – visual field testing (some from behind them and see if they see your fingers) Gonioscopy – visualization to determine open or closed Optic Nerve imagine – to determine nerve damage

TEACHING (MOST IMPORTANT)→ how to take drops, teach about side affects Surgical TX: Trabeculectomy/ Trabeculoplasty (laser)

Two drugs → wait 5 min between each one

When drugs don’t work for OAG

Handwashing Keep tip of container clean (don’t touch to eye)

Contact DR if sudden loss of vision/pain afterwards

Punctual occlusion (so doesn’t go systemic)

Constrict the pupil Reduce production/ ↑ absorption of aqueous humor Prostaglandin agonist → DON’T USE if cornea not intact, lashes may grow longer in the eye that is used, don’t use in eye that’s not affected will ↓ IOP and cause vision loss Adrenergic Agonists → may ↑ BP and cause hypertensive crisis, pupils dilate and allow more light (wear sunglasses) Beta- adrenergic blockers → caution in pt w asthma/COPD, may cause hypoglycemia, may ↓ BP/HR

NURSING INTERVENTIONS

Medications Q 12 hours

DRUGS (967) DO NOT improve vision, prevent more damage by ↓ IOP pressure

Eye exams @ different ages

Cholinergic agonist → systemic affects (headache, flushing, ↑ saliva & sweating Carbonic anhydrase inhibitor → like sulfonamides (SULFA allergies), need to SHAKE drug, absorbed by contact lens, leave contacts out for 15 minutes

Corneal Disorders (usually transparent, clear layer over eye) Corneal issues/ Causes Corneal problems can lead to ↓ in vision and could cause blindness

Teaching Wear gloves when examine the eye

Anti-infective therapy is started (broad spectrum first)

Corneal Abrasion (977) Why most corneal abrasions treated topically instead of oral? →oral harder to reach eye; if you have corneal scratch or abrasion feels okay when wake up (eyelid closed so starts to heal- tiny vessels bring O2 and nutrients when eye closed)

Steroids may be used w antibiotics

Corneal Abrasions CAUSES: Scape/scratch

Instill eye drops Q hour, for first 24 hours → Label bottles

Painful, ↓ vision, photophobia, ↑ secretions

Post op care → subconjunctival antibiotic injection, antibiotic ointment, pressure patch and protective shield to cover eye, DO NOT use icepack on eye, LAY on unaffected side to reduce IOP

Do not wear contacts until infection is gone

Malnutrition, dry eyes, some cancer TX

Eye Donation

Contact lens users

Corneal tissue from donors free of infectious disease or

Fluorescein stain is used Causes → irritation (allergies & rub eyes a lot), infection (lead to scars on cornea), ulceration of the cornea, degeneration of the cornea, deposits in the cornea “corneal scratch → can’t look at sun, when go outside eye hurts, in the morning pain & exudate → very sensitive to light”

Avoid using makeup until recovery of the eye

Keratoplasty – surgical removal of diseases corneal tissue and replacement with tissue from human doner cornea, regional anesthesia

Abrasions, organism enter, corneal infections

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