Glaucoma

MEDICAL SURGICAL NURSING - II BSC NURSING III YEAR EYE DISORDER

1. Mr. Manikandan.T , RN., RM., M.Sc (N)., D.C.A .,( Ph.D ) Assistant Professor, Dept. of Medical Surgical Nursing, VMCON, Puducherry . GLAUCOMA

2. Definition It is not one disease but rather a group of disorder characterized by I ncreased IOP and the consequences of elevated pressure, Optic nerve atrophy Peripheral visual field loss

3. Etiology It is related to the consequences of elevated IOP. A proper balance between the rate of aqueous production and rate of aqueous reabsorption is essential to maintain the IOP normal limits. When the rate of inflow is greater than rate of outflow, IOP can rise above the normal limits. If IOP remains elevated, permanent vision loss occurs.

4. Risk factors Age Race Family history of glaucoma Medical conditions- Diabetes mellitus, Cardiovascular disease Physical injuries - Eye trauma Near sightedness Corticosteroids use Eye abnormalities • Thin cornea

5. Types Open angle glaucoma: Usually bilateral, but one eye may be more severely affected than the other. The anterior chamber angle is open and appears normal. Angle closure glaucoma: Obstruction in aqueous humor outflow due to the complete or partial closure of the angle from the forward shift of the peripheral iris to the trabecula . The obstruction results in an increased IOP.

6. Open-Angle Glaucoma 1)Primary open-angle glaucoma (POAG): Optic nerve damage, visual field defects, IOP >21 mm Hg. May have fluctuating IOPs. Usually no symptoms but possible ocular pain, headache, and halos. 2)Normal tension glaucoma: IOP </- 21 mm Hg. Optic nerve damage, visual field defects. 3)Ocular hypertension: Elevated IOP. Possible ocular pain or headache.

7. Angle closure glaucoma ( Pupillary Block) Acute angle-closure glaucoma (AACG): Rapidly progressive visual impairment, periocular pain, conjunctival hyperemia, and congestion. Pain may be associated with nausea, vomiting, bradycardia , and profuse sweating. Reduced central visual acuity, severely elevated IOP, corneal edema. Pupil is vertically oval,fixed in a semidilated position, and unreactive to light and accommodation. Subacute angle-closure glaucoma : Transient blurring of vision, halos around lights; temporal headaches and/or ocular pain; pupil may be semidilated . Chronic angle-closure glaucoma : Progression of glaucomatous cupping and significant visual field loss; IOP may be normal or elevated; ocular pain and headache.

8. Clinical manifestation chronic open-angle glaucoma : Loss of peripheral vision due to compression of retinal rods and nerve fibers . Halos around lights as a result of corneal edema. Mild aching in the eyes caused by increased IOP Reduced visual acuity, especially at night, not correctable with glasses.

9. C/M acute angle-closure glaucoma Inflammation, Red, painful eye caused by an abrupt elevation of IOP. Sensation of pressure over the eye due to increased IOP. Moderate papillary dilation nonreactive to light. Cloudy cornea due to compression of intraocular components Blurring and decreased visual acuity due to aberrant neural conduction. Photophobia due to abnormal intraoccular pressures. Halos around lights due to corneal edema. Nausea and vomiting caused by increased IOP.

10. Diagnostic evaluation History collection. Physical examination. Visual acuity examination . Tonometry . Ophthalmoscopy . Slit lamp microscopy. Gonioscopy – it is  performed with the head positioned in the slit lamp (the special microscope used to look at the eyes). After numbing the eye with drops, a special contact lens is placed directly on the eye and a beam of light is used to illuminate the angle. ... Examination of both eyes typically takes a few minutes Visual field perimetry . Fundus photography.

11. Management Lifelong therapy is almost always necessary because glaucoma cannot be cured. Drug therapy: Beta blockers - timolol Alpha adrenergic agonist- brimonidine Cholinergic agents – pilocarpine – increases A.Q outflow Carbonic anhydrase - acetazolamide Adrenergic aganost - Epinephrine, to reduce I0P by improving aqueous outflow Prostaglandins - latanoprost , to reduce intraocular pressure.

12. Cont., Treatment for acute angle-closure glaucoma is an ocular emergency requiring immediate intervention to reduce high IOP including: I.V. mannitol (20%) or oral glycerin (50%), to reduce IOP by creating an osmotic pressure gradient between the blood and intraocular fluid Steroid drops- to reduce inflammation Acetazolamide , a carbonic anhydrase inhibitor, to reduce IOP by decreasing the formation and secretion of aqueous humor Pilocarpine - to constrict the pupil, forcing the iris away from the trabeculae and allowing fluid to escape timolol , a beta-blocker - to decrease IOP. Narcotic analgesics, to reduce pain if necessary.

13. Surgical therapy Argon laser trabecuoplasty : laser burns are applied to the inner surface of the trabecular meshwork to open the intratrabecular spaces and widen the canal of Schlemm , thereby promoting outflow of aqueous humor and decreasing IOP. laser iridotomy : for pupillary block glaucoma, an opening is made in the iris to eliminate the pupillary block.

14. Filtering procedures- Trabeculectomy Trabeculectomy is the standard filtering technique used to remove part of the trabecular meshwork. Surgeon used to create an opening or fistula in the trabecular meshwork to drain aqueous humor from the anterior chamber to the subconjunctival space into a bleb (fluid collection on the outside of the eye), thereby bypassing the usual drainage structures. This allows the aqueous humor to flow and exit by different routes ( ie , absorption by the conjunctival vessels or mixing with tears).

15. Drainage implants or shunts Drainage implants or shunts are open tubes implanted in the anterior chamber to shunt aqueous humor to the episcleral plate in the conjunctival space. These implants are used when failure has occurred with one or more trabeculectomies in which antifibrotic agents were used. A fibrous capsule develops around the episcleral plate and filters the aqueous humor, thereby regulating the outflow and controlling IOP.

16. Trabectome trabectome surgery stabilizes the optic nerve and minimizes further visual field damage. The surgery is performed through a small incision and does not require creation of a permanent hole in the eye wall or an external filtering bleb or an implant.

17. Glaucoma complication Blindness Nursing intervention Encourage patient compliance by teaching the patient about medications, as ordered, to dilate the pupil and protect the affected eye . Administer pain medication as ordered . Encourage the patient to be ambulatory immediately after surgery. Nursing process: The patient with Glaucoma.

18. Nursing Assessment The patient should be assessed for loss of both central and peripheral vision, discomfort, understanding of disease and compliance with treatment regimen, and ability to conduct activities of daily living.

19. Nursing Diagnosis. Nursing diagnoses may include the following: Acute pain related to increased intraocular pressure . Disturbed sensory perception: visual related to altered sensory reception. Self-care deficit related to decreased vision. Anxiety related to partial or total visual loss. Risk for injury related to decreased vision. Impaired home maintenance related to decreased vision. Deficient knowledge related to medical regimen, disease process due to no prior experience.

20. Nursing planning Planning for nursing interventions needs to take into account the patient’s level of understanding of disease process and medical regimen and ability to comply with the time-consuming medication regimen. The goal of nursing care for the glaucoma patient is to prevent further visual loss and to promote comfort if the patient is experiencing pain as in acute glaucoma. The patient who needs surgical intervention has additional goals.

21. Nursing Intervention The patient is taught how to administer medications and performs a return demonstration to ensure that eye drops are administered properly. If the patient has trouble with a steady hand when administering eye drops, teach the patient to rest his or her hand on the forehead to steady the hand. If the patient is unable to see the label on the eye drop bottle, consider large-print labels or audiotaped directions. For patients with multiple medications, consider using large, multicolored dot stickers placed on medication bottle with a corresponding direction card with a matching colored dot. Patients are taught the need for having regular eye examinations through dilated pupils.

22. Evaluation Patient goals are met if the patient does the following: Maintains an acceptable level of comfort Has no further loss of vision Is able to care for self with assistance if needed Expresses concerns and anxieties Does not suffer injury as a result of the visual impairment Is able to manage home maintenance with assistance if needed Demonstrates correct instillation of eye medications Is able to verbalize understanding of condition and treatment.