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Etiology, treatment of glaucoma
W;lhelmina Fernsebner, RN
EtioIogy, treatment of glaucoma Glaucoma is an eye disease characterized by an increase in intraocular pressure which, if untreated, leads to atrophy of the optic nerve and ultimate blindness. Fifteen percent of adult blindness in the United States is due to glaucoma, and statistics show that one in every 50 persons over 40 years of age has the disease with or without symptoms. The incidence may reach 5% to 9% in the older age group. People over 40 and those with family history of the disease are more susceptible than others. In 1967, a Public Health Service report stated that 1 million persons over 35 years of age have undetected glaucoma, and one blind person in seven is needlessly blind due to the disease. There seems to be little difference in the incidence between the sexes although the angle closure type is more prevalent in women. Physiology and pathophysiology. Aqueous humor is secreted by the epithelium of the ciliary processes into the posterior chamber of the eye located behind the iris. The aqueous then flows between the iris and the lens forward through the pupillary aperture and into the anterior chamber. It then passes through the trabecular meshwork and into Sch-
996
lemm’s canal, ultimately entering the venous system of the sclera through the aqueous veins. In a normal eye, the flow will maintain the intraocular pressure between 12 and 23 mm Hg.’ The etiology of glaucoma is found in the anterior one-third of the eye; in almost all cases the elevated intraocular pressure is due to an obstruction of the outflow of aqueous through Schlemm’s canal. Infrequently hypersecretion of aqueous is a cause. When the aqueous cannot escape through the normal route, intraocular pressure increases and is transmitted to all parts of the eye. The constant elevation of pressure causes atrophy and degeneration of the optic nerve. T.ypes of glaucoma. The two broad categories are open angle and angle closure, referring to the angle of the anterior chamber where the cornea and iris meet. Each category has a further classification of primary and secondary. Primary refers t o genetic predisposition, and secondary results from other ocular disease, trauma, or surgery. Congenital glaucoma is usually considered separately although it falls into the classification of open angle glaucoma. Open angte glaucoma. The onset of
AORN JournaE, DecembeF 1974, VoC20, No 5
.. iris l ' P " o 1 . Y l ~ r m.slll"Yrl
anterior chamber angle canal of Schlernm ciliary body
The two broad categories of glaucoma are open angle, top, and angle closure, bottom, referring to the angle of the anterior chamber where the cornea and iris meet.
open angle glaucoma is usually insidious, and symptoms frequently do not occur until there is permanent damage to the optic nerve. The diagnosis is made by tonometry using a Schiotz or applanation tonometer and examination of the optic nerve heads using an ophthalmoscope. These tests may be done during a routine ophthalmological examination or in one of the many glaucoma screening clinics that communities and civic organizations sponsor.
Other tests are gonioscopy, perimetry, and tonography. The goaI of treatment for open angle glaucoma is to reduce intraocular pressure either by increasing the facility of outflow or decreasing the rate of secretion of aqueous. Medical treatment includes miotic drugs, applied topically, to increase the facility of outflow; topical epinephrine which increases the facility of outflow as well as decreasing the formation of aqueous; and carbonic-anhydrase-inhibiting drugs, given orally, to decrease the rate of formation of aqueous. If medical treatment fails, surgery may be necessary. It is performed primarily to improve the facility of outflow. Most surgical procedures performed are filtering operations. A fistula is formed through the corneoscleral wall permitting the aqueous to drain from the anterior chamber into the space between the conjunctiva and Tenon's capsule. Some of the most common filtering techniques are: Trephining: A small conjunctival flap is made and reflected to the limbus. Then using a 1 or 1.5 mm trephine, a button is cut at the corneoscleral junction through the anterior chamber. A peripheral iridectomy is performed through the opening after the corneoscleral button is removed. With suturing of the conjunctival incision, an enclosed subconjunctival space is provided for drainage of aqueous. 0 Iridencleisis: A linear incision is made a t the corneoscleral junction into the anterior chamber. The iris is incarcerated into the incision to act as a wick, allowing the aqueous to drain into the subconjunctival space.
AORN Journal, December 1974, Vol20, N o 6
997
0 Sclerectomy: This procedure is similar to trephining, except a punch is used to remove the button rather than a trephine. 0 Cyclodialysis: A scleral incision is made behind the limbus, and a spatula is inserted forward between the ciliary body and the sclera until the tip can be seen in the anterior chamber. It is then swept to strip the ciliary body from its attachment to the scleral spur. Aqueous drains through the channel into the suprachoroidal space where it is absorbed by the choroidal circulation. 0 Cyclocryotherapy is used when all other treatment has failed. A 3 mm cryoprobe is applied to the surface of the eye, overlying the ciliary body. The probe is cooled to a low (-67 C or lower) temperature, freezing the ciliary body and decreasing its secretory function. Angle closure glaucoma. The onset of acute angle closure glaucoma is usually episodic. The iris-trabecular apposition may allow a rapid increase in intraocular pressure due to the mechanical obstruction of aqueous outflow. This sudden increase in pressure often causes pain, blurred vision, appearance of colored haloes around lights, and, frequently, nausea and vomiting. (Often angle closure is misdiagnosed as a disease of gastrointestinal, dental, sinus, or neurological origin.) External examination will show the pupil dilated, often slightIy irregular, with little or no reaction to light. Gonioscopy is necessary to make the definitive diagnosis of angle closure glaucoma but may be difficult in an acutely congested eye with a hazy cornea. The cornea may be cleared with lowering of intraocular pressure by one of several forms of medical treatment, al-
998
lowing the surgeon to see the then narrow or closed angle. The tension, as shown by the Schiotz or applanation tonometer, will be elevated. In the midst of an acute attack, intraocular pressure may be as high as 100 mm Hg. Angle closure glaucomas are always surgical problems with medical therapy useful only as a preIude to surgery. It cannot be considered adequately treated until an opening has been made in the iris to allow aqueous to flow again into the anterior chamber. Surgery must be prompt as any delay, with the iris-meshwork apposition continuing, may result in a permanent adhesion and a continuing glaucoma requiring more extensive surgery. Peripheral iridectomy, the operation performed for angle closure, is the safest of the glaucoma operations when performed skillfully and is one of the few glaucoma operations that is almost always curative. The operation is usually performed under local anesthesia, but general anesthesia can be administered if necessary, The operation is performed through a small incision made at the limbus beneath a flap of conjunctiva that has been reflected away from the cornea. The iris is then prolapsed through the wound where it is held with forceps and a piece excised. Frequently a gush of aqueous can be seen as the iris is cut and pressure released. This hole in the iris (iridectomy) allows aqueous to flow from the posterior to the anterior chamber, relieving a relative block of aqueous flow a t the pupil. The wound is closed with a 7-0 silk or chromic suture. As predisposing factors which may cause angle closure are almost always bilateral, the fellow eye
AORN Journal, December 1974, Vol20, No 6
T
ouch is especially
important to eye patients. should be treated with miotics until the first eye is out of danger and a prophylactic iridectomy can be performed.2 The hospital stay is generally two to four days, and medication is discontinued when examination shows minimal congestion. At this time gonioscopy and tonography can be performed to evaluate permanent damage, if any, and probable prognosis. Although angle closure represents a small minority of all glaucomas, recognition is extremely important especially by nonophthalmic personnel. It requires immediate surgical treatment which is usually successful. Congenital glaucoma. In congenital glaucoma, developmental anomalies are present at birth. Some early signs and symptoms are photophobia, tearing, and blepharospasm. Corneal edema or hazing may appear either early or late and is usually the first symptom that concerns parents enough to seek medical advice. As intraocular pressure increases, the cornea becomes noticeably larger. If help is not sought before that time, the eye may be irreversibly damaged. Children with congenital glaucoma must have frequent eye examinations to ascertain any damage and whethe r surgery is required. Examination includes testing of intraocular pressure with a tonometer. Because it is usually impossible to examine young children adequately in an office, many children are brought to the operating room for examination un-
der anesthesia. If surgery is required, it may be performed a t the same time. When tensions are to be taken, neither barbituates nor halothane can be used as both these drugs alter intraocular pressure. Ether is often the agent of choice, requiring a long induction time and a long emergence time. OR nurses should be aware of the potential hazards when ether is administered and take appropriate precautions. The initial treatment for congenital glaucoma is surgery-either goniotomy, goniopuncture, or combination of both. Goniotomy is performed by inserting a fine knife through the cornea and, under direct visualization, into the anterior chamber. The tip of the knife is brought across the chamber to the opposite angle where an abnormally dense trabecular membrane is incised. Aqueous then has access to the Schlemm’s canal and aqueous veins. Goniopuncture produces an external filtration by means of a tiny puncture through the trabecular meshwork into the subconjunctival space. Role of the operating room nurse. As most glaucoma procedures are performed under local anesthesia, the circulating nurse’s main concern will be for the patient’s comfort and safety. The patient must be able to assume a position and maintain it for at least an hour. A pillow placed under the knees can help relieve strain on the back. The arms should be placed by the patient’s side and
AORN Journal, December 1974, Vol20, No 6
999
Definifions of glaucoma diagnostic tests Gonioscopy. Gonioscopy i s a biomicroscopic examination of the angle of the anterior chamber. It i s necessary in diagnosing what type of glaucoma i s present. The examination i s done with a gonioscopic contact lens placed over the cornea. Lighting i s obtained from a Barkan Light and viewing done with either a hand-held or counterbalanced corneal microscope and/or slit lamp. Preoperatively, this examination helps determine which eye is in danger of angle closure and which i s safe from closure, as well as defining the secondary glaucomas. In the case of angle closure glaucoma gonioscopy i s used postoperatively to evaluate the success of an iridectomy in opening the angle. Tonometry. Tonometry is used to measure intraocular pressure and to recognize abnormal pressure. The Schiotz tonometer i s the most widely used instrument. It is placed on the anesthetized cornea, and the intraocular pressure i s reflected indirectly depending upon how deeply the plunger of the tonometer indents the cornea. The harder the eye,
either tucked under a draw sheet or restrained with soft wristlets. All patients should have cardiac monitoring and frequent blood pressure checks because there can be vital sign changes with local anesthesia. If there is an anesthetist standby, he will monitor the vital signs and also start an infusion. Medication such as diazepam can be given intravenously for additional relaxation. Air should be provided through an air hose attached to a face mask or nasal cannula. Touch is especially important to eye patients and they will frequently
1000
the lower the scale reading and the higher the intraocular pressure. Ophthalmoscopy. The interior of the eye i s examined with a small beam of light reflected through the pupil while the examiner looks through a small opening in the mirror of the ophthalmoscope. This examination allows the evaluation of the optic disc, retina and blood vessels. Perimetry. Perimetry measures the peripheral field and will delineate any loss of vision from glaucoma, With the eye fixed a t a central point, peripheral and side vision can b e accurately measured by one of several types perimetry. The tangent screen, with a dull, black finish is often used to measure central fields. Tonography. Tonography is the recording of the intraocular pressure over a period of four minutes. The readings are recorded on a graph similar to an electrocardiogram and are valuable t o the ophthalmologist in determining the adequacy of the trabecular drainage systems.
want to hold your hand (or the anesthetist’s) throughout surgery, or at least during the injection of local anesthesia. It is reassuring to the patient to know someone is there. The circulating nurse is responsible for administering topical anesthesia (proparacaine Hcl 0.5 % ) drops prior to prepping the eye. It is wise to instill one drop in the fellow eye as insurance against stinging from a stray splash of soap or alcohol. Noise should be kept at a minimum during the entire procedure. If necessary, the surgeon should be reminded that his patient is awake and
AORN Journal, December 1974, V o l 2 0 , No 6
aware of what is being said. Many of our surgeons play radios for background music during the surgery. The patient requiring a peripheral iridectomy as emergency surgery for acute-angle closure will frequently be nauseated, and any move of the stretcher or transfer from stretcher to table should be gentle. Osmoglyn or acetazolamide are often given preoperatively to reduce intraocular pressure. Since these drugs act as diuretics, the patient should be offered a bedpan or urinal in the holding area before entering the operating room. The pediatric patient is always special. Many of our children are frequent visitors, and the staff knows them and their special needs. We allow dolls, stuffed animals, and blankets in the operating room with the child until he is asleep. Blankets producing static, however, are not allowed when ether is being used. We try to remember to patch their doll's or animal's eye before the procedure is over. Postoperative care. For most patients, surgery will be under local anesthesia. They will not have to stay in the recovery room unless there has been a change in vital signs warranting closer observation than can be provided on the floor. Patients returning directly to their room should be told to ask for pain medication when and if they need it. They should also be told not to get out of bed by themselves. Patients having general anesthesia will stay in the recovery room until their vital signs are stable and they are oriented enough to time and place to safely return to their rooms. As medications are frequently given the glaucoma patient to either constrict
or dilate the pupil, it is impossible to use pupil dilation to check for level of anesthesia. If a child has had ether, his recovery stay will be longer than usual due to the longer action of the anesthetic. Summary. Surgery is used as treatment for open-angle glaucoma only when medical treatment fails, although surgery is always performed for acute-angle closure glaucoma. The OR nurse should not only be prepared to assist the surgeon and care for the patient during glaucoma surgery; she should also be an advocate for routine eye examinations. Through perseverance, glaucoma can be sought out and diagnosed early. With early treatment, the prognosis is good for a life with adequate vision. Without early detection and treatment, the patient may face a life of unnecessary blindness.
The author wishes to acknowledge the assistance of B Thomas Hutchinson, MD, and Ellen Davis, R N , in preparing this article. Dr Hutchinson is an ophthalmologist, Massachusetts Eye and Ear Infirmary (MEEI), and Ms Davis is head nurse, eye surgery, MEEI. Notes I. Paul Chandler, W Morton Grant, Lecturer on Glaucoma (Philadelphia: Lea and Febiger, 1965) 13. 2. /bid, 179. References Chandler, Paul A, W Morton Grant. Lectures on Glaucom~. Philadelphia: Lea and Febiger, 1965. Scheie, Harold 6,Daniel M Albert. Adler'r Texthook of Ophthalmology. Philadelphia: W B Saunderr, 1969. U S Dept of Health, Education, and Welfare, Public Health Service. Cafarucf und Glaucoma, Publication #793. Washington DC: U S Govt Printing Office, 1967.
AORN Journal, December 1974, V o l 2 0 , No 6
1001
EtioIogy, treatment of glaucoma Glaucoma is an eye disease characterized by an increase in intraocular pressure which, if untreated, leads to atrophy of the optic nerve and ultimate blindness. Fifteen percent of adult blindness in the United States is due to glaucoma, and statistics show that one in every 50 persons over 40 years of age has the disease with or without symptoms. The incidence may reach 5% to 9% in the older age group. People over 40 and those with family history of the disease are more susceptible than others. In 1967, a Public Health Service report stated that 1 million persons over 35 years of age have undetected glaucoma, and one blind person in seven is needlessly blind due to the disease. There seems to be little difference in the incidence between the sexes although the angle closure type is more prevalent in women. Physiology and pathophysiology. Aqueous humor is secreted by the epithelium of the ciliary processes into the posterior chamber of the eye located behind the iris. The aqueous then flows between the iris and the lens forward through the pupillary aperture and into the anterior chamber. It then passes through the trabecular meshwork and into Sch-
996
lemm’s canal, ultimately entering the venous system of the sclera through the aqueous veins. In a normal eye, the flow will maintain the intraocular pressure between 12 and 23 mm Hg.’ The etiology of glaucoma is found in the anterior one-third of the eye; in almost all cases the elevated intraocular pressure is due to an obstruction of the outflow of aqueous through Schlemm’s canal. Infrequently hypersecretion of aqueous is a cause. When the aqueous cannot escape through the normal route, intraocular pressure increases and is transmitted to all parts of the eye. The constant elevation of pressure causes atrophy and degeneration of the optic nerve. T.ypes of glaucoma. The two broad categories are open angle and angle closure, referring to the angle of the anterior chamber where the cornea and iris meet. Each category has a further classification of primary and secondary. Primary refers t o genetic predisposition, and secondary results from other ocular disease, trauma, or surgery. Congenital glaucoma is usually considered separately although it falls into the classification of open angle glaucoma. Open angte glaucoma. The onset of
AORN JournaE, DecembeF 1974, VoC20, No 5
.. iris l ' P " o 1 . Y l ~ r m.slll"Yrl
anterior chamber angle canal of Schlernm ciliary body
The two broad categories of glaucoma are open angle, top, and angle closure, bottom, referring to the angle of the anterior chamber where the cornea and iris meet.
open angle glaucoma is usually insidious, and symptoms frequently do not occur until there is permanent damage to the optic nerve. The diagnosis is made by tonometry using a Schiotz or applanation tonometer and examination of the optic nerve heads using an ophthalmoscope. These tests may be done during a routine ophthalmological examination or in one of the many glaucoma screening clinics that communities and civic organizations sponsor.
Other tests are gonioscopy, perimetry, and tonography. The goaI of treatment for open angle glaucoma is to reduce intraocular pressure either by increasing the facility of outflow or decreasing the rate of secretion of aqueous. Medical treatment includes miotic drugs, applied topically, to increase the facility of outflow; topical epinephrine which increases the facility of outflow as well as decreasing the formation of aqueous; and carbonic-anhydrase-inhibiting drugs, given orally, to decrease the rate of formation of aqueous. If medical treatment fails, surgery may be necessary. It is performed primarily to improve the facility of outflow. Most surgical procedures performed are filtering operations. A fistula is formed through the corneoscleral wall permitting the aqueous to drain from the anterior chamber into the space between the conjunctiva and Tenon's capsule. Some of the most common filtering techniques are: Trephining: A small conjunctival flap is made and reflected to the limbus. Then using a 1 or 1.5 mm trephine, a button is cut at the corneoscleral junction through the anterior chamber. A peripheral iridectomy is performed through the opening after the corneoscleral button is removed. With suturing of the conjunctival incision, an enclosed subconjunctival space is provided for drainage of aqueous. 0 Iridencleisis: A linear incision is made a t the corneoscleral junction into the anterior chamber. The iris is incarcerated into the incision to act as a wick, allowing the aqueous to drain into the subconjunctival space.
AORN Journal, December 1974, Vol20, N o 6
997
0 Sclerectomy: This procedure is similar to trephining, except a punch is used to remove the button rather than a trephine. 0 Cyclodialysis: A scleral incision is made behind the limbus, and a spatula is inserted forward between the ciliary body and the sclera until the tip can be seen in the anterior chamber. It is then swept to strip the ciliary body from its attachment to the scleral spur. Aqueous drains through the channel into the suprachoroidal space where it is absorbed by the choroidal circulation. 0 Cyclocryotherapy is used when all other treatment has failed. A 3 mm cryoprobe is applied to the surface of the eye, overlying the ciliary body. The probe is cooled to a low (-67 C or lower) temperature, freezing the ciliary body and decreasing its secretory function. Angle closure glaucoma. The onset of acute angle closure glaucoma is usually episodic. The iris-trabecular apposition may allow a rapid increase in intraocular pressure due to the mechanical obstruction of aqueous outflow. This sudden increase in pressure often causes pain, blurred vision, appearance of colored haloes around lights, and, frequently, nausea and vomiting. (Often angle closure is misdiagnosed as a disease of gastrointestinal, dental, sinus, or neurological origin.) External examination will show the pupil dilated, often slightIy irregular, with little or no reaction to light. Gonioscopy is necessary to make the definitive diagnosis of angle closure glaucoma but may be difficult in an acutely congested eye with a hazy cornea. The cornea may be cleared with lowering of intraocular pressure by one of several forms of medical treatment, al-
998
lowing the surgeon to see the then narrow or closed angle. The tension, as shown by the Schiotz or applanation tonometer, will be elevated. In the midst of an acute attack, intraocular pressure may be as high as 100 mm Hg. Angle closure glaucomas are always surgical problems with medical therapy useful only as a preIude to surgery. It cannot be considered adequately treated until an opening has been made in the iris to allow aqueous to flow again into the anterior chamber. Surgery must be prompt as any delay, with the iris-meshwork apposition continuing, may result in a permanent adhesion and a continuing glaucoma requiring more extensive surgery. Peripheral iridectomy, the operation performed for angle closure, is the safest of the glaucoma operations when performed skillfully and is one of the few glaucoma operations that is almost always curative. The operation is usually performed under local anesthesia, but general anesthesia can be administered if necessary, The operation is performed through a small incision made at the limbus beneath a flap of conjunctiva that has been reflected away from the cornea. The iris is then prolapsed through the wound where it is held with forceps and a piece excised. Frequently a gush of aqueous can be seen as the iris is cut and pressure released. This hole in the iris (iridectomy) allows aqueous to flow from the posterior to the anterior chamber, relieving a relative block of aqueous flow a t the pupil. The wound is closed with a 7-0 silk or chromic suture. As predisposing factors which may cause angle closure are almost always bilateral, the fellow eye
AORN Journal, December 1974, Vol20, No 6
T
ouch is especially
important to eye patients. should be treated with miotics until the first eye is out of danger and a prophylactic iridectomy can be performed.2 The hospital stay is generally two to four days, and medication is discontinued when examination shows minimal congestion. At this time gonioscopy and tonography can be performed to evaluate permanent damage, if any, and probable prognosis. Although angle closure represents a small minority of all glaucomas, recognition is extremely important especially by nonophthalmic personnel. It requires immediate surgical treatment which is usually successful. Congenital glaucoma. In congenital glaucoma, developmental anomalies are present at birth. Some early signs and symptoms are photophobia, tearing, and blepharospasm. Corneal edema or hazing may appear either early or late and is usually the first symptom that concerns parents enough to seek medical advice. As intraocular pressure increases, the cornea becomes noticeably larger. If help is not sought before that time, the eye may be irreversibly damaged. Children with congenital glaucoma must have frequent eye examinations to ascertain any damage and whethe r surgery is required. Examination includes testing of intraocular pressure with a tonometer. Because it is usually impossible to examine young children adequately in an office, many children are brought to the operating room for examination un-
der anesthesia. If surgery is required, it may be performed a t the same time. When tensions are to be taken, neither barbituates nor halothane can be used as both these drugs alter intraocular pressure. Ether is often the agent of choice, requiring a long induction time and a long emergence time. OR nurses should be aware of the potential hazards when ether is administered and take appropriate precautions. The initial treatment for congenital glaucoma is surgery-either goniotomy, goniopuncture, or combination of both. Goniotomy is performed by inserting a fine knife through the cornea and, under direct visualization, into the anterior chamber. The tip of the knife is brought across the chamber to the opposite angle where an abnormally dense trabecular membrane is incised. Aqueous then has access to the Schlemm’s canal and aqueous veins. Goniopuncture produces an external filtration by means of a tiny puncture through the trabecular meshwork into the subconjunctival space. Role of the operating room nurse. As most glaucoma procedures are performed under local anesthesia, the circulating nurse’s main concern will be for the patient’s comfort and safety. The patient must be able to assume a position and maintain it for at least an hour. A pillow placed under the knees can help relieve strain on the back. The arms should be placed by the patient’s side and
AORN Journal, December 1974, Vol20, No 6
999
Definifions of glaucoma diagnostic tests Gonioscopy. Gonioscopy i s a biomicroscopic examination of the angle of the anterior chamber. It i s necessary in diagnosing what type of glaucoma i s present. The examination i s done with a gonioscopic contact lens placed over the cornea. Lighting i s obtained from a Barkan Light and viewing done with either a hand-held or counterbalanced corneal microscope and/or slit lamp. Preoperatively, this examination helps determine which eye is in danger of angle closure and which i s safe from closure, as well as defining the secondary glaucomas. In the case of angle closure glaucoma gonioscopy i s used postoperatively to evaluate the success of an iridectomy in opening the angle. Tonometry. Tonometry is used to measure intraocular pressure and to recognize abnormal pressure. The Schiotz tonometer i s the most widely used instrument. It is placed on the anesthetized cornea, and the intraocular pressure i s reflected indirectly depending upon how deeply the plunger of the tonometer indents the cornea. The harder the eye,
either tucked under a draw sheet or restrained with soft wristlets. All patients should have cardiac monitoring and frequent blood pressure checks because there can be vital sign changes with local anesthesia. If there is an anesthetist standby, he will monitor the vital signs and also start an infusion. Medication such as diazepam can be given intravenously for additional relaxation. Air should be provided through an air hose attached to a face mask or nasal cannula. Touch is especially important to eye patients and they will frequently
1000
the lower the scale reading and the higher the intraocular pressure. Ophthalmoscopy. The interior of the eye i s examined with a small beam of light reflected through the pupil while the examiner looks through a small opening in the mirror of the ophthalmoscope. This examination allows the evaluation of the optic disc, retina and blood vessels. Perimetry. Perimetry measures the peripheral field and will delineate any loss of vision from glaucoma, With the eye fixed a t a central point, peripheral and side vision can b e accurately measured by one of several types perimetry. The tangent screen, with a dull, black finish is often used to measure central fields. Tonography. Tonography is the recording of the intraocular pressure over a period of four minutes. The readings are recorded on a graph similar to an electrocardiogram and are valuable t o the ophthalmologist in determining the adequacy of the trabecular drainage systems.
want to hold your hand (or the anesthetist’s) throughout surgery, or at least during the injection of local anesthesia. It is reassuring to the patient to know someone is there. The circulating nurse is responsible for administering topical anesthesia (proparacaine Hcl 0.5 % ) drops prior to prepping the eye. It is wise to instill one drop in the fellow eye as insurance against stinging from a stray splash of soap or alcohol. Noise should be kept at a minimum during the entire procedure. If necessary, the surgeon should be reminded that his patient is awake and
AORN Journal, December 1974, V o l 2 0 , No 6
aware of what is being said. Many of our surgeons play radios for background music during the surgery. The patient requiring a peripheral iridectomy as emergency surgery for acute-angle closure will frequently be nauseated, and any move of the stretcher or transfer from stretcher to table should be gentle. Osmoglyn or acetazolamide are often given preoperatively to reduce intraocular pressure. Since these drugs act as diuretics, the patient should be offered a bedpan or urinal in the holding area before entering the operating room. The pediatric patient is always special. Many of our children are frequent visitors, and the staff knows them and their special needs. We allow dolls, stuffed animals, and blankets in the operating room with the child until he is asleep. Blankets producing static, however, are not allowed when ether is being used. We try to remember to patch their doll's or animal's eye before the procedure is over. Postoperative care. For most patients, surgery will be under local anesthesia. They will not have to stay in the recovery room unless there has been a change in vital signs warranting closer observation than can be provided on the floor. Patients returning directly to their room should be told to ask for pain medication when and if they need it. They should also be told not to get out of bed by themselves. Patients having general anesthesia will stay in the recovery room until their vital signs are stable and they are oriented enough to time and place to safely return to their rooms. As medications are frequently given the glaucoma patient to either constrict
or dilate the pupil, it is impossible to use pupil dilation to check for level of anesthesia. If a child has had ether, his recovery stay will be longer than usual due to the longer action of the anesthetic. Summary. Surgery is used as treatment for open-angle glaucoma only when medical treatment fails, although surgery is always performed for acute-angle closure glaucoma. The OR nurse should not only be prepared to assist the surgeon and care for the patient during glaucoma surgery; she should also be an advocate for routine eye examinations. Through perseverance, glaucoma can be sought out and diagnosed early. With early treatment, the prognosis is good for a life with adequate vision. Without early detection and treatment, the patient may face a life of unnecessary blindness.
The author wishes to acknowledge the assistance of B Thomas Hutchinson, MD, and Ellen Davis, R N , in preparing this article. Dr Hutchinson is an ophthalmologist, Massachusetts Eye and Ear Infirmary (MEEI), and Ms Davis is head nurse, eye surgery, MEEI. Notes I. Paul Chandler, W Morton Grant, Lecturer on Glaucoma (Philadelphia: Lea and Febiger, 1965) 13. 2. /bid, 179. References Chandler, Paul A, W Morton Grant. Lectures on Glaucom~. Philadelphia: Lea and Febiger, 1965. Scheie, Harold 6,Daniel M Albert. Adler'r Texthook of Ophthalmology. Philadelphia: W B Saunderr, 1969. U S Dept of Health, Education, and Welfare, Public Health Service. Cafarucf und Glaucoma, Publication #793. Washington DC: U S Govt Printing Office, 1967.
AORN Journal, December 1974, V o l 2 0 , No 6
1001