1. Copyright © 2014 by Mosby, an imprint of Elsevier Inc.
Glaucoma
Chapter 22
Copyright © 2014 by Mosby, an imprint of Elsevier Inc.

2. Copyright © 2014 by Mosby, an imprint of Elsevier Inc.
Glaucoma
A group of disorders characterized by
Increased IOP and consequences of elevated pressure
Optic nerve atrophy
Peripheral visual field loss
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3. Copyright © 2014 by Mosby, an imprint of Elsevier Inc.
Glaucoma
At least 2 million persons have glaucoma
50% are unaware
Second leading cause of blindness
Leading cause of blindness in African Americans
Another 10 million persons have elevated IOP, placing them at increased risk of developing the disease.
The incidence of glaucoma increases with age.
Blindness from glaucoma is largely preventable with early detection and appropriate treatment.
Genetic factors have been identified in some types of glaucoma.
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4. Etiology and Pathophysiology
A proper balance between the rate of aqueous production (inflow) and the rate of aqueous reabsorption (outflow) is essential to maintain the IOP within normal limits.
The place where the outflow occurs is called the “angle,” as it is the angle where the iris meets the cornea.
When the rate of inflow is greater than the rate of outflow, IOP can rise above normal limits. If IOP remains elevated, permanent vision loss may occur.
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5. Copyright © 2014 by Mosby, an imprint of Elsevier Inc.
Case Study
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S.H. , a 66-year-old female, comes to your community health screening and tells you she is having some trouble seeing.
She says it “runs in the family.”
What can you teach the patient about the importance of seeing an ophthalmologist?
Teach her that there are some very serious eye problems that run in families. Ask her more about her symptoms and explain that early detection and treatment is often very important in preventing further loss of sight and its complications.
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6. Etiology and Pathophysiology
Primary open-angle glaucoma (POAG)
Most common type of glaucoma
Outflow of aqueous humor is ↓ in trabecular meshwork
In POAG, the outflow of aqueous humor is decreased in the trabecular meshwork.
In essence, the drainage channels become clogged, like a clogged kitchen sink.
Damage to the optic nerve can then result.
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7. Etiology and Pathophysiology
Primary angle-closure glaucoma (PACG)
Angle closure ↓ the flow of aqueous humor
Caused by age, pupil dilation
Possibly drug induced
Primary angle-closure glaucoma (PACG) is caused by a reduction in the outflow of aqueous humor that results from angle closure.
Usually, this is caused from the lens bulging forward as a result of the aging process.
Angle closure may also occur as a result of pupil dilation in the patient with anatomically narrow angles.
An acute attack may be precipitated by situations in which the pupil remains in a partially dilated state long enough to cause an acute and significant rise in IOP. This may occur because of drug-induced mydriasis, emotional excitement, or darkness.
Drug-induced mydriasis may occur not only from topical ophthalmic preparations but also from many systemic medications (both prescription drugs and over-the-counter [OTC] drugs). Check drug records and documentation before administering medications to the patient with angle-closure glaucoma, and instruct the patient not to take any mydriatic-producing medications.
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8. Clinical Manifestations
POAG
Develops slowly
No symptoms
Unnoticed until peripheral vision is severely compromised
Eventually the patient with untreated glaucoma has “tunnel vision,” in which only a small center field can be seen and all peripheral vision is absent.
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9. Clinical Manifestations
Acute angle-closure glaucoma
Sudden onset
Excruciating pain in or around eyes
Nausea and vomiting
Seeing colored halos around lights
Blurred vision
Ocular redness
PACG causes sudden and definite symptoms.
Manifestations of subacute or chronic angle-closure glaucoma appear more gradually.
The patient who has had a previous, unrecognized episode of subacute angle-closure glaucoma may report a history of blurred vision, seeing colored halos around lights, ocular redness, or eye or brow pain.
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10. Copyright © 2014 by Mosby, an imprint of Elsevier Inc.
Case Study
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S.H. confides that actually, she has “tunnel vision” and very bad shooting pain in her eyes lately.
How much should you be concerned and why?
You should be very concerned about the possibility of acute angle-closure glaucoma and its potential effects. Early diagnosis and treatment is indicated.
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11. Clinical Manifestations
IOP elevated in glaucoma
Normal IOP 10 to 21 mm Hg
Open-angle glaucoma 22 to 32 mm Hg
Acute angle-closure glaucoma >50 mm Hg
IOP is usually elevated in glaucoma.
Normal IOP is 10 to 21 mm Hg.
In the patient with elevated pressures, the ophthalmologist usually will repeat the measurements over a period of time to verify the elevation.
In open-angle glaucoma, IOP is usually between 22 and 32 mm Hg.
In acute angle-closure glaucoma, IOP may be >50 mm Hg.
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12. Courtesy National Eye Institute, National Institutes of Health
Diagnostic Studies
Courtesy National Eye Institute, National Institutes of Health
Diagnostic studies can be completed with slit lamp microscopy, peripheral and central vision tests, and ophthalmoscopy.
In open-angle glaucoma, slit lamp microscopy reveals a normal angle. In angle-closure glaucoma, the examiner may note a markedly narrow or flat anterior chamber angle, an edematous cornea, a fixed and moderately dilated pupil, and ciliary injection (hyperemia of the ciliary blood vessels produces a red color).
Measures of peripheral and central vision provide other diagnostic information. Whereas central acuity may remain 20/20 even in the presence of severe peripheral visual field loss, visual field perimetry may reveal subtle changes in the peripheral retina early in the disease process, long before actual scotomas develop.
In acute angle-closure glaucoma, central visual acuity will be reduced if the patient has corneal edema, and the visual fields may be markedly decreased.
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Ophthalmoscopy
As glaucoma progresses, optic disc cupping may be one of the first signs of chronic open-angle glaucoma. The optic disc becomes wider, deeper, and paler (light gray or white,) which is visible with direct or indirect ophthalmoscopy.
Copyright © 2014 by Mosby, an imprint of Elsevier Inc.

14. Copyright © 2014 by Mosby, an imprint of Elsevier Inc.
Case Study
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You insist that S.H. see an ophthalmologist, but she insists that she sees “just fine” if she turns her head a lot.
How should you handle her reluctance to seek treatment?
Listen to what she has to say. Gather more information about her symptoms. Inquire about her knowledge of her symptoms and what they might mean. Try to find out more about her resources for health care treatment and coverage.
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Collaborative Care
Chronic open-angle glaucoma
Drug therapy
Argon laser trabeculoplasty
Laser stimulates scarring and contraction of trabecular meshwork
Trabeculectomy
The primary focus of glaucoma therapy is to keep the IOP low enough to prevent the patient from developing optic nerve damage. Therapy varies with the type of glaucoma.
Initial treatment in chronic open-angle glaucoma is with drugs (Table 22-7). The patient must understand that continued treatment and supervision are necessary because the drugs control, but do not cure, glaucoma.
Argon laser trabeculoplasty (ALT) is a noninvasive option to lower IOP when medications are not successful, or when the patient either cannot or will not use the drug therapy as recommended.
ALT is an outpatient procedure that requires only topical anesthetic.
The laser stimulates scarring and contraction of the trabecular meshwork, which opens the outflow channels.
ALT reduces IOP approximately 75% of the time. The patient uses topical corticosteroids for approximately 3 to 5 days after the procedure. The most common complication is an acute postoperative IOP rise.
Follow-up exams are scheduled with the ophthalmologist 1 week after the procedure and again 4 to 6 weeks following surgery.
Trabeculectomy is a filtration surgery with 75% to 80% success rate.
Indicated when medical management and laser surgery have been unsuccessful
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Collaborative Care
Acute angle-closure glaucoma
Miotics
Oral/IV hyperosmotic
Laser peripheral iridotomy
Surgical iridectomy
Acute angle-closure glaucoma is an ocular emergency that requires immediate intervention.
Miotics (see Table 22-7) and oral or IV hyperosmotic agents including glycerin liquid (Ophthalgan), isosorbide solution (Ismotic), and mannitol solution (Osmitrol) are usually successful in immediately lowering the IOP.
A laser peripheral iridotomy or surgical iridectomy is necessary for long-term treatment and prevention of subsequent episodes. These procedures allow the aqueous humor to flow through a newly created opening in the iris and into normal outflow channels. One of these procedures may also be performed on the other eye as a precaution, because many patients often experience an acute attack in the other eye.
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17. Nursing Management Nursing Assessment
Patient’s ability to understand and comply with treatment
Patient’s psychologic reaction to sight-threatening disorder
Family reaction and support
Caregiver availability
Glaucoma is a chronic condition and thus has long-term management concerns and ramifications.
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18. Nursing Management Nursing Diagnoses
Risk for injury
Self-care deficits
Acute pain
Noncompliance
Risk for injury related to visual acuity deficits
Self-care deficits related to visual acuity deficits
Acute pain related to pathophysiologic process and surgical correction
Noncompliance related to the inconvenience and side effects of glaucoma medications
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19. Nursing Management Planning
Expected goals
No progression of visual impairment
Understanding of disease process and rationale for therapy
Compliance with all aspects of therapy
No postoperative complications
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20. Nursing Management Nursing Implementation
Health promotion
Teach patient and family risks of glaucoma, and that it increases with age
Emphasize importance of early detection and treatment
Provide ophthalmologic examinations
Loss of vision because of glaucoma is a preventable problem.
Teach the patient and family about the risk of glaucoma, and that it increases with age.
Emphasize the importance of early detection and treatment in preventing visual impairment.
A comprehensive ophthalmic examination is important in identifying persons with glaucoma and those at risk of developing glaucoma. The current recommendation is for an ophthalmologic examination every 2 to 4 years for persons between ages 40 and 64 years, and every 1 to 2 years for persons age 65 years or older. African Americans in every age category should have examinations more often because of the increased incidence and more aggressive course of glaucoma in these individuals.
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21. Nursing Management Nursing Implementation
Acute intervention
Administer medication to lower IOP
For surgical patients
Provide post-op instructions
Relieve discomfort
Acute nursing interventions are directed primarily toward the patient with acute angle-closure glaucoma and the surgical patient.
The patient with acute angle-closure glaucoma requires immediate medication to lower the IOP
It must be administered in a timely and appropriate manner according to the ophthalmologist’s prescription.
Most surgical procedures for glaucoma are outpatient procedures. Acutely, the patient needs postoperative instructions and may require nursing measures to relieve discomfort related to the procedure. Patient and caregiver teaching after eye surgery is discussed in Table 22-3.
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22. Nursing Management Nursing Implementation
Ambulatory and home care
Remind patient to follow therapy
Teach about
Disease process
Treatment options and their rationale
Information about the purpose, frequency, and technique for administration of antiglaucoma drugs
Because of the chronic nature of glaucoma, remind the patient to follow the therapeutic regimen and follow-up recommendations as prescribed by the ophthalmologist.
Provide accurate information about the disease process and treatment options, including the rationale underlying each option. In addition, the patient needs information about the purpose, frequency, and technique for administration of antiglaucoma drugs.
Encourage compliance by helping the patient identify the most convenient and appropriate times for medication administration or by advocating a change in therapy if the patient reports unacceptable side effects.
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23. Copyright © 2014 by Mosby, an imprint of Elsevier Inc.
Case Study
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S.H. tells you she is all alone—no husband or children, and her best friend and neighbor died last year.
If she is diagnosed with glaucoma, what can you tell her about possible treatments?
She can pursue nonsurgical options if she is unsure about surgery. These treatments may help slow the progression of the disease. Surgical treatments are available and effective. Most can be done on an outpatient basis with fairly quick recovery time. There are support services available to help people with their health problems and ADLs affected by the treatment for them.
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24. Nursing Management Evaluation
Expected outcomes
No further loss of vision
Compliance with recommended therapy
Safe functioning in the environment
Pain relief from disease and surgery
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25. Nursing Management Gerontologic Considerations
Tend to the special needs of the older adult
Caution about potential drug interactions that occur with systemic illnesses and their treatments
Teach that occluding the puncta will limit systemic absorption of glaucoma medications
Many older patients with glaucoma have systemic illnesses or take systemic medications that may affect their therapy.
In particular, the patient using a β-adrenergic blocking glaucoma agent may experience an additive effect if a systemic β-adrenergic blocking drug is also being taken.
All β-adrenergic blocking glaucoma agents are contraindicated in the patient with bradycardia, heart block greater than first-degree heart block, cardiogenic shock, and overt cardiac failure.
The noncardioselective β-adrenergic blocker glaucoma agents are also contraindicated in the patient with chronic obstructive pulmonary disease (COPD) or asthma.
The hyperosmolar agents may precipitate heart failure or pulmonary edema in the susceptible patient.
The older patient on high-dose aspirin therapy for rheumatoid arthritis should not take carbonic anhydrase inhibitors.
The α-adrenergic agonists can cause tachycardia or hypertension, which may have serious consequences in the older patient.
Teach the older patient to occlude the puncta to limit the systemic absorption of glaucoma medications.
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26. Copyright © 2014 by Mosby, an imprint of Elsevier Inc.
Case Study
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As you talk more with S.H., she tells you more about her problems that include a history of hypertension, type 2 diabetes, and hyperlipidemia.
Why do these problems put her at greater risk for glaucoma?
Some of her medications may potentiate the effects of treatment for her possible glaucoma.
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27. Copyright © 2014 by Mosby, an imprint of Elsevier Inc.
Audience Response Question
The nurse instructs a patient with primary open-angle glaucoma about the disorder. Which of the following statements, if made by the nurse, is most appropriate?
“The retinal nerve is damaged by an abnormal increase in the production of aqueous humor.”
“Aqueous humor cannot drain from the eye, causing pressure damage to the optic nerve.”
“As the lens enlarges with aging, it pushes the iris forward, covering the outflow channels of the eye.”
“The lens blocks the pupillary opening, preventing the flow of aqueous humor into the anterior chamber. “
Answer: b
Rationale: In primary open-angle glaucoma, the outflow of aqueous humor is decreased in the trabecular meshwork. The drainage channels become clogged, and damage to the optic nerve can then result.
Copyright © 2014 by Mosby, an imprint of Elsevier Inc.