NURS 2863 Care of the Client with Sensory Disorders and neuro Questions & Answers

Care of the Client with Sensory Disorders Most of us will agree that the abilities to see, hear, taste, perceive touch, and smell are pretty important. Without the ability to smell, food would have little, if any, taste. The sense of touch lets us know when we experience something pleasurable or are injured. But of all the senses, the abilities to see and hear are considered most important because they keep us most informed about the world around us. This chapter reviews problems affecting vision and hearing. 1794/c 1794/c 1794/ Disorders of the Eyes Before discussing the various disorders of the eyes, it is important that you understand the anatomical structure of the eye. Figure 8.1 offers an illustration for reference. FIGURE 8.1 Structure of the eye. Disorders of the eyes can be divided into the following categories: Intraocular disorders: These arise from within the eyeball. Examples include cataracts and glaucoma. Retinal disorders: These arise from the innermost layers of the eyeball. Examples include hypertensive retinopathy, diabetic retinopathy, and macular degeneration. Refractive errors: These affect the eye’s ability to focus. Examples include myopia, hyperopia, presbyopia, and astigmatism. Traumatic injuries: These pose the risk of infection and loss of vision. Examples include hyphema, contusions, foreign bodies, lacerations, and penetrating injuries. Intraocular Disorders Intraocular disorders arise from within the eyeball. The primary intraocular disorders you need to understand include cataracts and glaucoma. The sections that follow discuss these two diseases in greater detail. Cataracts Cataracts, opacities in the lens of the eye, result in the distortion of images projected onto the retina. Cataracts are associated with aging, trauma, disease of the eye, prolonged use of steroids, and exposure to sunlight or ultraviolet light. Congenital cataracts of the newborn are characterized by the absence of the red reflex. Symptoms of cataracts include the following: Blurred, hazy vision Glare from bright lights Yellow, white, or gray discoloration of the pupil Gradual loss of vision Caution Cataract surgery is generally performed in an outpatient surgery center. The client is given a sedative to lessen anxiety. Medications such as Diamox (acetazolamide) are given to reduce intraocular pressure. Mydriatic eye drops such as Neo-Synephrine (phenylephrine) are used in combination with cycloplegics such as Cyclogyl (cyclophenolate HCl) to paralyze the muscles of accommodation. After the client is in the operative area, an intravenous injection of Versed (midazolam) can be given to induce light anesthesia during administration of local anesthesia. Removal of the affected lens is usually accomplished by an extracapsular cataract extraction (ECCE). The anterior portion of the lens is opened and removed along with the lens cortex and nucleus. The surgeon uses sound waves to break the affected lens into small pieces. These small pieces are then removed by suction. (This process is known as phacoemulsion.) The posterior lens capsule is left in place to provide support for the intraocular lens implant, a small plastic lens individually designed for the client. Although binocular vision and depth perception are immediately improved, most clients experience their best vision from four to six weeks after surgery. If an intraocular lens cannot be implanted, the client will be fitted with convex corrective glasses or contact lenses to correct vision. Antibiotic drops and steroid ointments are instilled in the operative eye immediately after surgery. In most instances, the operative eye is left unpatched. Postoperatively, the client is maintained in a semi-Fowler’s position to reduce swelling and to prevent stress on the new lens implant. Clients are usually discharged within two to three hours following surgery. Before discharging the client, the nurse should instruct the client to do the following: Avoid activities that would increase intraocular pressure, such as bending from the waist, blowing the nose, wearing tight shirt collars, closing the eyes tightly, and placing the head in a dependent position. Report sharp, sudden pain in the operative eye. Pain early after surgery might indicate bleeding or increased intraocular pressure. Report signs of infection, which include yellow or green discharge. Creamy white or whitish dry, crusty drainage is normal following cataract surgery. Report changes in vision including decreasing vision, flashes of light, or visual floaters. Take a tub bath or shower facing away from the water. Administer eye medication as directed. Wear a protective shield when sleeping. Return for follow-up visits as directed. Glaucoma Glaucoma refers to a group of diseases that result in an increase in intraocular pressure. Glaucoma is the second leading cause of permanent blindness in the United States and the second leading cause of blindness in the world, according to the World Health Organization. Blindness from glaucoma is largely preventable with early detection and treatment. The three types of glaucoma and their characteristics are as follows: Primary open-angle glaucoma (POAG): This is the most common form of glaucoma. POAG affects both eyes, is usually asymptomatic, and is caused by a decrease in the outflow of aqueous humor. The intraocular pressure in those with POAG averages between 22 mm Hg and 32 mm Hg. Symptoms of POAG include the following: Tired eyes Diminished peripheral vision Seeing halos around lights Hardening of the eyeball Increased intraocular pressure Acute glaucoma: This condition, sometimes called narrow-angle glaucoma or primary angle-closure glaucoma (PACG), is less common than primary open-angle glaucoma. Acute glaucoma is caused by a sudden reduction in the outflow of aqueous humor due to angle closure. Angle closure can result from the lens bulging forward (an age-related process) or from pupil dilation in the client with anatomically narrow angles. The condition can be precipitated by the use of mydriatics, emotional upset, or darkness. The onset of severe eye pain is sudden and without warning. Emergency treatment is necessary because rising intraocular pressure can exceed 30 mm Hg. Symptoms of acute glaucoma include the following: Sudden, excruciating pain around the eyes Headache or aching in the eyebrow Nausea and vomiting Cloudy vision Pupil dilation Secondary glaucoma: This is caused by ocular conditions that narrow the canal of Schlemm or that alter eye structures that are involved in the production and circulation of aqueous humor. Secondary glaucoma is managed by treating the underlying ocular condition and by the use of anti-glaucoma medications. Note The normal intraocular pressure ranges from 10 to 21 mm Hg. Management of a Client with Glaucoma Conservative management of the client with POAG is aimed at reducing intraocular pressure with medications. Miotic eye drops such as Isopto Carpine (pilocarpine HCl) are instilled to constrict the pupil and increase the outflow of aqueous humor. Beta blockers such as Timoptic (timolol) and carbonic anhydrase inhibitors like Diamox (acetazolamide) decrease the production of aqueous humor, thereby lowering the intraocular pressure. Prostaglandin analogs such as Xalatan (latanoprost) administered daily are the drugs of choice for the treatment of chronic glaucoma. Prostaglandin analogs have fewer side effects, but can cause permanent changes in the color of the iris and eyebrows. Trabeculoplasty and trabeculectomy filtration surgery are the most commonly used surgical procedures used for the treatment of chronic open angle glaucoma. Note Nursing Skill: Application of Eye Medications Before instilling medication into the eyes, the lids and lashes should be cleaned using warm water. Only sterile ophthalmic preparations should be used. The nurse should avoid touching the eye with the applicator. Ointments should be applied from the inner to outer canthus of the eye. Eye drops should be dropped into the lower lid while the client is looking up. Gentle pressure should be placed over the tear duct, and the client should be instructed to refrain from tightly closing the eyelids. Argon laser trabeculoplasty is an option when medications are not effective in reducing the intraocular pressure. A filtering procedure or trabeculectomy is indicated when medication and laser therapy are not successful. The success rate for trabeculectomy is between 75% and 85%. Surgical implantation of a small tube to shunt the aqueous humor away from the anterior chamber to an implanted reservoir is reserved for those in whom the filtering procedure failed. Acute glaucoma or PACG is an ocular emergency that requires immediate intervention. Osmotics diuretics such as Osmitrol (mannitol), and carbonic anhydrase inhibitors such as acetazolamide, can be administered via IV to clients with acute glaucoma to rapidly reduce intraocular pressure and prevent permanent damage to the optic nerve. Fast-acting miotic drops, such as pilocarpine, can also be used. Laser peripheral iridotomy or iridectomy is necessary for long-term management and the prevention of future episodes. Most surgical procedures for glaucoma are performed in outpatient surgery. Postoperatively, the client is placed in semi-Fowler’s position and instructed to lie on the unaffected side, to avoid taking aspirin, and to report severe eye or brow pain. Changes in vital signs, a decrease in vision, and acute pain deep in the eye are symptoms of choroidal hemorrhage. These findings should be reported to the physician immediately. Uveitis Uveitis refers to inflammation of the iris, the ciliary body, and the choroid which together make up the uveal tract. Uveitis can occur in either the anterior or posterior portion of the eye. Anterior uveitis affects the iris, ciliary body, or both. The cause is unknown; however, the condition can follow local or systemic infections, exposure to allergens, trauma, or systemic diseases such as rheumatoid arthritis or herpes zoster. Manifestations of anterior uveitis include periorbital aching, tearing, photophobia, visual blurring, pupillary changes (small, irregular, nonreactive pupils), and reddened “bloodshot” sclera. Posterior uveitis includes inflammation of the retina, the choroid, or both. The condition occurs in clients with tuberculosis, syphilis, and toxoplasmosis. The onset of symptoms is slow and painless. The client has small, irregular, nonreactive pupils and visual impairment. Fundoscopic examination reveals grayish-yellow patches on the surface of the retina. Management of the client with uveitis includes the use of topical cycloplegics, mydriatics, and steroids. Topical steroids are administered hourly to reduce inflammation and to prevent adhesion of the iris to the cornea and lens. Nonaspirin and nonopioid analgesics are given for pain and discomfort. Systemic antibiotics may be used. Additional comfort measures include cool or warm compresses for ocular pain. The use of sunglasses helps manage the client’s photophobia. Corneal Dystrophy and Corneal Transplantation Corneal dystrophy refers to the accumulation of cloudy material in parts of the cornea, which is usually clear. Corneal dystrophies are typically inherited disorders that gradually affect the vision in both eyes in some instances leading to the loss of vision. Corneal transplantation (keratoplasty) replaces the diseased cornea with a healthy donor cornea. Corneas are harvested from uninfected adults under the age of 65 who die as the result of trauma. The transplant can be either lamellar or penetrating. In the lamellar transplant, the superficial layer of the cornea is removed and replaced with a graft. In the penetrating transplant, a button or full thickness of cornea is removed and replaced by the donor tissue. The graft is sutured in place with suture finer than the human hair. An air bubble is usually instilled to help the graft adhere. The client should remain in bed with the head of the bed flat for at least an hour after surgery. The client should avoid bending over as this may cause the graft to disconnect. Hospitalization is usually not required. The eye is patched for 24 hours. Narcotics can be given for pain, because the cornea is extremely sensitive. Corticosteroids and antibiotics are usually ordered to reduce inflammation and to decrease the risk of infection. The risk of rejection is low and current success rates are approximately 80%. When rejection does occur, it occurs within 3 weeks of transplantation. Signs of rejection begin with inflammation at the edge of the grafted tissue, which spreads to the entire graft. Retinal Disorders Retinal disorders involve disorders of the innermost layer of the eye. The most common retinal disorders are hypertensive retinopathy, diabetic retinopathy, and macular degeneration. Less common retinal disorders include retinitis pigmentosa and retinal detachment. The following sections cover these retinal disorders in greater detail. Hypertensive Retinopathy Hypertensive retinopathy occurs in the client with a long history of uncontrolled hypertension. Elevations in diastolic blood pressure create a copper wire appearance in the retinal arterioles. If the blood pressure remains elevated, arterioles become occluded by the formation of soft exudates known as cotton wool spots. Treatment focuses on control of systemic hypertension. Left untreated, hypertensive retinopathy can result in retinal detachment and loss of vision. Diabetic Retinopathy Diabetic retinopathy is the result of vascular changes associated with uncontrolled diabetes mellitus. Vascular changes are inherent in all diabetics; however, good control of blood sugar helps reduce the severity of the disease. The two types of diabetic retinopathy are as follows: Background diabetic retinopathy: This leads to the development of micro- aneurysms and intraretinal hemorrhages. Proliferative diabetic retinopathy: This leads to the development of new, fragile blood vessels that leak blood and protein into the surrounding tissue. The treatment of diabetic retinopathy depends on the type and the degree of tissue involvement. Laser surgery can be used to seal microaneurysms and prevent bleeding. Age-Related Macular Degeneration Age-related macular degeneration affects the portion of the eye involved with central vision. The two types of age-related macular degeneration are as follows: Atrophic (dry): This form is characterized by sclerosing of retinal capillaries with loss of rod and cone receptors, decreased central vision, and complaints of mild blurred vision. The condition progresses faster in smokers than nonsmokers. The risk for age-related macular degeneration can be reduced by a diet rich in antioxidants; lutein; zeaxanthin; and carotenoids found in dark green, leafy vegetables as well as yellow vegetables such as carrots and sweet potatoes. Exudative (wet): This form is characterized by a sudden decrease in vision due to serous detachment of the pigmented epithelium of the macula. Blisters composed of fluid and blood form underneath the macula, resulting in scar formation and decreasing vision. Treatment of age-related macular degeneration is aimed at slowing the process. Laser therapy can be used to seal leaking blood vessels near the macula; however, this can cause retinal scarring and lead to blind spots. Newer procedures for treating wet age-related macular degeneration include photodynamic therapy using intravenous Visudyne (verteporfin), a dye, and cold laser to destroy the abnormal blood vessels; Macugen(pegaptamib) given intravenously to inhibit endothelial growth and slow vision loss; and Lucentis (ranibizumab), a biologic therapy injected monthly that blocks new vessel growth and leakiness. Persons at risk for age-related macular degeneration should supplement their diet with vitamins and minerals, particularly vitamin C, vitamin E, beta- carotene, and zinc. Retinitis Pigmentosa Retinitis pigmentosa is a condition that results in degeneration of retinal nerve cells. As these nerve cells die, the pigmented cells of the retina grow and move into the sensory areas of the retina, leading to further degeneration. Different forms of the disorder have been identified as being an autosomal dominant trait, an autosomal recessive trait, or an X- linked recessive trait. Early symptoms include night blindness that frequently occurs in childhood. Visual acuity declines until the client is totally blind. Currently, no therapy-proven effective means exists to prevent or slow the progression of the disorder, although experimental treatments include a regimen of vitamin A and decreased exposure to bright light. Retinal Detachment Retinal detachment can result from a blow to the head, fluid accumulation in the subretinal space, or the aging process. Generally, the condition is pain-free; however, the client might complain of the following symptoms: Blurred vision Flashes of light Visual floaters A veil-like loss of vision Management of Clients with Retinal Detachment Conservative management usually involves placing the client with the area of detachment in a dependent position. The most common site for retinal detachment is the superior temporal area of the right eye. Sedatives and anxiolytics will make the client more comfortable. Spontaneous reattachment of the retina is rare, so surgical management is often required. The client with retinal detachment is usually referred to a retinal specialist for surgery. Surgical management includes laser photocoagulation or cryotherapy that creates a scar to seal the retina to the choroid or by scleral buckling (see Figure 8.2) to shorten the sclera and improve contact between the retina and choroid. Intravitreal injection of gas (pneumatic retinopexy) might be used to close retinal breaks. FIGURE 8.2 Scleral buckling. Postop activity varies with the procedure used. If gas or oil has been instilled during the scleral buckling, the client is positioned on her abdomen with her head turned so that the operative eye faces upward. This position is maintained for several days or until the gas or oil is absorbed. An alternative is to allow the client to sit on the bedside and place her head on an overbed table. Bathroom privileges are allowed, but the client must keep her head bowed. The following discharge instructions should be given to the client with a scleral buckling: Report any sudden increase in pain or pain accompanied by nausea. Avoid reading, writing, and close work for the first postop week. Do not bend over so that the head is in a dependent position. Be careful not to bump the head. Refractive Errors Refractory errors refer to the capability of the eyes to focus images on the retina. Refractory errors are due to an abnormal length of the eyeball from front to back and the refractive power of the lens. Refractory errors include the following: Myopia (nearsightedness): Images focus in front of rather than on the retina; this is corrected by a concave lens. Hyperopia (farsightedness): Images focus behind rather than on the retina; this is corrected by a convex lens. Presbyopia: The crystalline lens loses elasticity and becomes unable to change shape to focus the eye for close work so that images fall behind the retina; this condition is age- related. Astigmatism: An uneven curvature of the cornea causes light rays to be refracted unequally so that a focus point on the retina is not achieved. Nonsurgical management of refractory errors includes the use of eyeglasses and contact lenses. Surgical management includes the following: Radial keratotomy (RK): This treatment is used for mild to moderate myopia. Eight to 16 cuts are made through 90% of the peripheral cornea. The incisions decrease the length of the eye by flattening the cornea. This allows the image to focus nearer the retina. Photorefractive keratotomy (PRK): This is used for the treatment of mild to moderate stable myopia and low astigmatism. An excimer laser is used to reshape the superficial cornea using powerful beams of ultraviolet light. One eye is treated at a time with a wait period of three months between surgeries. Complete healing can take up to six months. Laser in-situ keratomileusis (LASIK): This is used for the treatment of nearsightedness, farsightedness, and astigmatism. An excimer laser is used to reshape the deeper corneal layers. Both eyes are treated at the same time. Complete healing can take up to four weeks. LASIK is thought to be better than PRK because the outer layer of the cornea is not damaged, there is less pain, and the healing time is reduced. Intacs corneal ring: This is used for those with mild to moderate nearsightedness. The shape of the cornea is changed by using a polymeric ring on the outer edges of the cornea. The surgery does not involve the use of laser and is reversible Anesthetic eye drops are instilled to make the client more comfortable during the procedure. No needles or injections are required. The surgeon makes two tiny incisions through which the Intacs is inserted. The incisions are closed with a single stitch that is removed in a few days. The procedure usually takes 15–20 minutes for each eye. Postoperative nursing care is minimal. Antibiotic and anti-inflammatory eye drops are prescribed to prevent infection and relieve local irritation. The client’s vision should be sufficient to drive a car, 20/40 or better, on the first postoperative day. The vision should continue to improve over the next 6–12 months. Replacement rings can be inserted if the client’s vision changes with aging. Traumatic Injuries Traumatic injuries to the eyes can occur from any activity. Traumatic injuries and their treatments include the following: Hyphema: Hemorrhage in the anterior chamber as the result of a blow to the eye. Treatment includes bed rest in semi-Fowler’s position, no sudden eye movement for three to five days, cycloplegic eye drops, use of an eye patch and eye shield to protect the eye, and limited television viewing and reading. Contusion: Bruising of the eyeball and surrounding tissue. Treatment includes ice to the affected area and a thorough eye exam to rule out other eye injuries. Elevating the client’s head 30°– 45° will help to minimize edema and swelling. Foreign bodies: Objects that irritate or abrade the surface of the conjunctiva or cornea. Treatment includes transporting the client to the ER with both eyes covered by a cupped object, a visual assessment by a physician before treatment and instillation of fluorescein followed by irrigation with normal saline to remove foreign particles. Lacerations and penetrating injuries: Corneal lacerations are considered emergencies because ocular contents can prolapse through the laceration. Treatment can require the administration of IV antibiotics and surgery. Caution Objects protruding from the eye should never be removed by anyone except an ophthalmologist because greater damage can occur, including the displacement of ocular structures. Clients with penetrating eye injuries have the poorest prognosis for retaining vision. Ocular Melanoma Ocular melanoma, the most common form of malignant eye tumor, might or might not be readily apparent. Symptoms associated with ocular melanoma depend on the involved structures. The following structures might be affected: Macula, resulting in blurred vision Choroid, resulting in decreased visual acuity Canal of Schlemm, resulting in increased intraocular pressure Iris, resulting in changes in color of the iris Retina, resulting in retinal detachment Treatment of ocular melanoma depends on the tumor size and growth rate. Tumors of the choroid are treated by enucleation and/or radiation. Following enucleation, a ball implant is inserted to provide a base for the socket prosthesis and to insure cosmetic results. An ocular prosthesis is fitted one month after surgery. Until the prosthesis is fitted, an antibiotic-steroid ointment is inserted into the cul-de-sac daily. Nursing care of the client with an ocular prosthesis includes the proper insertion and removal of the device. Insertion of the ocular prosthesis includes the following steps: 1. Cover the chest with a cloth or towel. 2. Wash the hands and