Group of ocularconditions characterized by opticnervedamage
Glaucoma
Caused by increased intraocular pressure (IOP) or optic neuropathy
Second leading cause of blindness in US adults
More prevalent in > 40 years; More in African Americans than Caucasians
No cure
Aqueous humor flow
1. Flows between the iris and the lens then out the anteriorchamber into the canal of Schlemm and the episcleral veins
2. Unimpeded outflow depends on an intactdrainagesystem and an open angle between the iris and the cornea
Aqueous humor and IOP
Amount of aqueous humor decreases with age and with diabetes and ocular inflammation conditions
When aqueous humor production = drainage, then IOP is within normal
When aqueous humor isn't draining = increased IOP
IOP
Changes with time of day, exertion, diet and medications
Increases with blinking, tight lid squeezing and upward gazing
Diabetes and intraocular conditions (uveitis and retinal detachment) are associated with increased IOP
Pathophysiology of glaucoma
Direct Mechanical Theory: High IOP damages the retinal layer as it passes through the optic nerve head
Indirect Ischemic Theory: High IOP compresses the microcirculation in the optic nerve head = cell injury and death
Most are a combination
Clinical manifestations of glaucoma
May not seek care until: Blurred vision, See "halos" around lights, Difficulty focusing, Difficulty adjusting eyes in low lighting, Loss of peripheral vision, Aching or discomfort around eyes, Headache
Stages of glaucoma
Initiating Events
Structural Alteration in the Aqueous Outflow System
Functional Alterations
Optic Nerve Damage
Visual Loss
As optic nerve damage increases, visual perception in the area is lost
Goal of glaucoma treatment
Prevent optic nerve damage
Glaucoma cannot be cured
Maintain IOP within range unlikely to cause further damage
Try to lower IOP by 30% and more if needed
Pharmacologic therapy for glaucoma
Beta-Blockers
Cholinergics (miotics)
Adrenergic agonists
Alpha Agonists
Prostaglandin analogues
Carbonic Anhydrase Inhibitors
Beta-Blockers
Preferred initially due to efficacy, minimal dosing and low cost
Blockade of sympathetic nerve endings in ciliary epithelium causing fall in aqueous humor production
Side effects: decreased BP, decreased pulse and fatigue
Cholinergics (miotics)
Increase the outflow of the aqueous humor by affecting ciliary muscle contraction and pupil constriction allowing flow through a larger opening between the iris and the trabecular meshwork
Increase drainage of intraocular fluid by making pupil size smaller thereby increasing fluid from eye
Side effects: dim vision especially at night or in darkened areas due to constriction of pupils
Adrenergic agonists and Alpha Agonists
Increase aqueous outflow, but primarily decrease aqueous production
Side Effects: Can burn and sting with eye drop, fatigue, headache, drowsiness, dry mouth and dry nose
Prostaglandin analogues
Reduce IOP by increasing aqueous humor outflow
Side effects: Eye redness, corneal deposits, stinging, small bleeds in the white of the eye
Carbonic Anhydrase Inhibitors
Reduce eye pressure by decreasing production of intraocular fluid
Side effects of pill – tingling and loss of strength in hands and feet, upset stomach, mental fuzziness, memory problems, depression, kidney stones, frequent urination
Side effects of eye drops – stinging, burning, eye discomfort
If the drugs don't work, surgical management is required
Nursing management of glaucoma
Teaching plan concerning medication regimen
Miotics and sympathomemetics = altered focus, need to be cautious when moving around
If blindness is worsening or legally blind, help with ADLs and referrals for help
Reassurance and emotional support
Cataracts
A lens opacity or cloudiness
3rd leading cause of disability in older adults
Leading cause of blindness in the world
About one in six of people over 40, more than half of people over 80
Reduced contrast sensitivity, sensitivity to glare, and reduced visual acuity
Myopic shift, Astigmatism, monocular diplopia, color shift, brunescens and reduced light transmission
Decreased visual acuity is directly proportionate to cataract density
Only surgical treatment, no nonsurgical treatment cures or prevents age-related cataracts
Cataract surgery
1. Outpatient surgery, usually takes 1 hour
2. One eye at a time with several weeks to months in between
Preoperative nursing management
CBC, EKG, UA and other tests specific to patient
To give or not to give anticoagulant?
Dilating drops every 10 minutes for four doses at least 1 hour before surgery
Antibiotic, corticosteroid, and anti-inflammatory drops for postoperative infection and inflammation prevention
Postoperative nursing management
Verbal and written instructions
Protection of eye
Medication administration
Signs of complications
Emergency care
Should be minimal discomfort, can take Tylenol
Antibiotic, anti-inflammatory, and corticosteroid eye drops or ointment are prescribed
Teaching self-care after cataract surgery
Wear a protective eye patch x 24 hours
Then, wear eyeglasses during the day and metal shield at night x 1-4 weeks
May have some slight morning discharge, some redness and a scratchy feeling x a few days
Notify physician if develop new floaters (dots) in vision, flashing lights, decrease in vision, pain, or increase in redness
Continuing care after cataract surgery
May experience blurring of vision for several days to weeks
Sutures, if necessary, are left in the eye and may result in some blurring and some astigmatism
Vision gradually improves as eye heals
Vision stabilizes after 6-12 weeks when eye is healed and final corrective prescription is completed
Retinal detachment
Separation of the retinal pigment epithelium (RPE)
Four types: Rhematogenous, Traction, Rhematogenous/Traction Combination, Exudative
Rhegmatogenous retinal detachment
Hole or tear develops in the sensory retina allowing liquid vitreous to seep through the sensory retina and detach it from the retinal pigment epithelium
Risk factors: Family History, High myopia (nearsightedness), Aphakia after cataract surgery, Trauma, Proliferative retinopathy, Associated with diabetic neovascularization
Traction retinal detachment
Caused by tension or pulling force
Generally, have fibrous scar tissue from diabetic retinopathy, vitreous hemorrhage, retinopathy of prematurity
Exudative retinal detachment
Result of serous fluid under the retina from the choroid
Caused by uveitis and macular degeneration
Clinical manifestations of retinal detachment
Sensation of a shade or curtain coming across the vision of one eye
Cobwebs
Bright flashing lights
Sudden onset of a great number of floaters
No complaint of pain
Pneumatic retinopexy
1. Gas bubble is injected into eye so the bubble presses against the detached retina and pushes it back into place
2. A laser or cryotherapy is then used to reattach the retina firmly into place
Nursing management of retinal detachment
Education and Supportive Care
Increased IOP
Signs and symptoms of Endophthalmitis (inflammatory condition of the intraocular cavities: the aqueous and vitreous humor)
More Retinal Detachments
Cataracts
Signs and symptoms of Postoperative Infection
Symptoms of endophthalmitis
Visual loss
Eye pain/irritation
Headache
Photophobia
Ocular Discharge
Intense Ocular and Periocular Inflammation
Postoperative positioning for pneumatic retinopexy
Prone or as instructed
Need the injected bubble to float into a position overlying the area of detachment providing constant pressure to reattach the sensory retina
Cannot fly - change in altitude causes bubble to expand and increasepressure inside the eye
Specific signs and symptoms to monitor for retinal detachment
Bright flashes of light
Floating dark spots = "Floaters"
Partial: "Curtain drawing over visual field" sensation
Loss of vision
Nursing actions for retinal detachment
1. Restrict activity to prevent additional detachment
2. Cover affected eye with patch
3. Monitor for drainage
4. Administer medications as prescribed (Mydriatics (dialating); Antiemetics; Analgesics)
5. Avoid activities that increase IOP: Bending over at the waist, Sneezing, coughing, Straining, Vomiting, Head hyperflexion, Wearing restrictive clothing (like a tight collar)