Recommendations for Ophthalmic Practice in Relation to the Human Immunodeficiency Virus
DENIS M. O'DAY and AMY CHOMSKY
Table Of Contents
PROTECTION OF THE PATIENT|
RISK OF ACQUIRING HIV INFECTION FROM EYE CARE PERSONNEL
PROTECTION OF HEALTH CARE PROVIDERS
GENERAL OFFICE PRECAUTIONS
POSTEXPOSURE PROTOCOL AND CHEMOPROPHYLAXIS
PATIENT AND HEALTH CARE PROVIDER PROTECTION SUMMARY
RESPONSIBILITIES TOWARD PATIENTS WITH KNOWN OR SUSPECTED HUMAN IMMUNODEFICIENCY VIRUS
|In 1985, in response to growing concerns,1 the National Society to Prevent Blindness, in cooperation with the American
Academy of Ophthalmology, assembled a task force to examine the
risk of becoming infected by human immunodeficiency virus (HIV) during
eye examinations and treatment. The unanimous conclusion of this task
force was that the risk was remote. Indeed, they believe that the potential
consequences of a denial of eye care because of a fear of acquiring
HIV infection posed a greater health risk.|
In August 1987, the Centers for Disease Control (CDC) issued revised recommendations for the prevention of HIV transmission in a health care setting.2 This was followed 2 months later by a joint advisory notice from the Department of Labor and the Department of Health and Human Services -regarding the protection against occupational ex-posure to hepatitis B virus (HBV) and HIV.3 These documents address the risk faced by health care workers in the course of their duties and make broad recommendations entitled, “Universal Precautions,” which all health care workers should follow. However, neither document distinguishes the particular risks and needs of health care workers in ophthalmology.
In June 1988, the CDC further clarified their recommendations, particularly as they relate to the protection of health care workers, by stressing the greater risk of blood-borne viral infections, such as HIV and HBV, posed by blood and blood-contaminated body fluids than by other body secretions such as tears.4
In view of the apparently low level of risk in ophthalmology compared with other more hazardous health care occupations and the lack of any published evidence of the transmission of HIV in ophthalmic health care settings, the American Academy of Ophthalmology and the National Society to Prevent Blindness, in consultation with the Contact Lens Association of Ophthalmologists, jointly established a committee to consider specific measures that would provide adequate protection for the patient, for eye health workers, and for the ophthalmologist. In this chapter, these measures are addressed in three distinct areas of concern:
|PROTECTION OF THE PATIENT|
|Protection of patients from exposure to the HIV during examination and
treatment of eye disorders incorporates the application of good public
health principles and specialized precautions. In the decade since the
infection was first recognized, there has been no evidence to indicate
that HIV has been transmitted through any of the diagnostic or surgical
procedures performed in the practice of ophthalmology. According
to the CDC, the likelihood of transmission through contact with tears
is remote.4 However, because the virus is potentially lethal, may be present in surface
epithelia in the eye, is in tears of certain infected individuals, and
can (at least in theory) be transmitted through mucous membranes, public
health officials recommend that reasonable precautions be taken. Further, because
many HIV carriers may be unaware of their infection
and show no sign of the disease, the following recommendations should
be routinely used for all patients. These guidelines represent good, general ophthalmic technique, since
they also reduce the risk of transmitting other blood-borne and
surface infectious agents (e.g., HBV, herpes virus, adenovirus) that are likely to be encountered in patients
presenting for eye examinations.|
Hand washing represents one of the most effective ways to avoid transmitting or acquiring infections during examination. Hands should be washed with soap and water and thoroughly dried by fresh or disposable towels between examinations. Increasingly, patients have come to expect and often request that this be done. If an open wound or weeping lesion is present on the health care worker's hands, disposable gloves should be worn. (Procedures to protect health care providers are discussed later.)
GOWNS AND MASKS
Gowns and masks are unnecessary for the usual ophthalmic examination.
INSTRUMENT DISINFECTION PROCEDURES
Given the low risk of transmitting HIV through contact with tears and the proven efficacy of 70% isopropyl alcohol against HIV, cleaning tonometer tips with an isopropyl alcohol sponge provides adequate protection against HIV.5 Ideally, the tip should be cleaned immediately after use and allowed to dry for at least 1 to 2 minutes before being used again. Care must be taken to cleanse the entire tip and to dry the tonometer surface thoroughly so that no alcohol is transferred to the ocular surface.
Some practitioners may wish to follow alternative recommendations, previously issued by the CDC, that have proved to eliminate HIV infectious agents: Wiping the instrument clean and then disinfecting it with a bleach solution is an effective way to eliminate HIV. The entire prism should be removed from the tonometer, wiped clean, and placed in a suitable receptacle, which allows the applanating surface and adjacent 2 to 3 mm of the tonometer to be immersed in a 1:100 dilution of household bleach. The 1:100 dilution is a broad-spectrum germicide. It is highly effective and rapidly acting, provided gross debris is removed from the tip before disinfection. Using a 1:10 concentration is unnecessary in most situations. One method uses a Petri dish with small holes drilled in the lid, sized to permit the tonometer tip to be partially immersed in the solution.6 After a 5-minute period of soaking, the tip should be washed under running water and dried before use. Corneal burns have resulted from incomplete rinsing of tonometer tips. Two tonometer prisms should be available so that one can be used while the other is being disinfected. Soaking the entire tip eventually removes the coloring of the etched calibration marks. Disinfecting solutions should be changed at least once daily.
As an alternative, the CDC recommends that 3% hydrogen peroxide be used in a similar disinfecting procedure. This solution needs to be changed at least twice daily.
To disinfect with alcohol, immerse the tip in 70% isopropyl or 70% ethyl alcohol for 5 minutes. However, the alcohol may dissolve the glue of the tonometer. Isopropyl alcohol may not be effective against adenovirus and other nonlipid viruses.7
The tonometer should be disassembled between each use; the barrel should be cleaned with two pipe cleaners (the first soaked in alcohol, the second dry), and the footplate cleaned with an alcohol swab. All surfaces must be dried before reassembly.
Tips of pneumotonometers should be cleaned with an alcohol sponge, taking care that the surface is dry before placing it in contact with the cornea.
The noncontact tonometer does not make contact with the cornea or tears and therefore is an ideal instrument for measurement of intraocular pressure in patients suspected of having any contagious viral condition. The front surface may be wiped with an alcohol-soaked sponge, since it occasionally can touch the eye or be splashed by tears.8
Diagnostic Contact Lenses (Gonio Lens, Macular Lens)
The lens is inverted so that the contact lens surface is uppermost. The outer casing and inner surface of the lens then is wiped with an alcohol sponge.
For added protection, the inner cup may be filled to the rim with a fresh 1:100 dilution of household bleach. After 5 minutes, the bleach is removed and the device is briskly irrigated with running water and dried. This method allows cleansing of the outer surface as well as the contact portion without exposing the glue, which cements the antireflective coating to the operator surface of the contact lens to the bleach.
Other Patient Contact Instruments
Routine cleaning with alcohol of all instrument surfaces (e.g., slit lamp) after each patient is impractical and unnecessary because HIV is a fragile virus, and there is no evidence of casual spread from surfaces. However, other viruses, such as adenovirus, may persist for many hours on a dry surface and, thus, could be transmitted to other patients.9 Therefore, if an instrument, such as a slit lamp, has been used for a patient who has an infectious disease, the surfaces of that instrument should be cleaned with alcohol.
Trial Fitting Contact Lenses
After each use, trial fitting contact lenses must be cleaned and then disinfected with a commercial product licensed by the US Food and Drug Administration (FDA). Chemical disinfection with a hydrogen peroxide system can be used for trial hard, rigid gas permeable and soft contact lenses. Some hard and soft contact lenses also can be disinfected with a standard heat system.1 The use of disposable soft lenses eliminates the need for disinfection. Although many of the newer products on the market have not been included in the CDC's 1985 recommendations,1 the FDA requires that these products are virucidal against at least one strain of herpes simplex type I.10 Because HIV is considered a more easily inactivated virus and studies have shown many of these to be effective against HIV, it can be presumed that these are safe to use as well.10–12
Routine cleaning with a surfactant cleaner, rinsing, and disinfection essentially eliminates the possibility of transmitting HIV.10
Corneal and scleral tissue that is used for transplantation should be screened for HIV and HBV in accordance with guidelines provided by the Eye Bank Association of America.13
|RISK OF ACQUIRING HIV INFECTION FROM EYE CARE PERSONNEL|
|The risk of patients acquiring the infection from an ophthalmologist or eye care personnel infected with the virus is considered remote. Standard office practices, as discussed earlier, minimize the risk of cross-contamination between patients and health care personnel. Surgical patients are protected by the routine use of barriers such as gloves. Certainly, an instrument that punctures the skin of an ophthalmologist or a surgical assistant must be removed from the operating field and sterilized. The surgeon or assistant must wash hands and reglove as soon as possible after such accidental injury occurs.|
|PROTECTION OF HEALTH CARE PROVIDERS|
|As the prevalence of acquired immunodeficiency syndrome (AIDS) continues
to increase throughout the United States, it is inevitable that patients
infected with HIV will be encountered in eye examining rooms and
in the operating room. Some will be known to be infected with the virus, but
it will be unrecognized in many. All health care personnel engaged
in delivering ophthalmic care to such patients may, during their normal
duties, be exposed to individuals who may be infected with a variety
of pathogenic microorganisms. Although the risk of infection in these
circumstances appears to be remote, precautions recently recommended
by the Occupational Safety and Health Administration (OSHA) appear
to be justified.3,14 The following hygienic procedures are recommended when delivering eye
care to patients. They are an effective way of minimizing the risk of
contracting or transmitting HIV and other more common infectious diseases
encountered in eye patients.15 Because it is impractical to identify all patients who may be carrying
these infectious agents, the recommendations should be routine for all
Ophthalmologists and staff may be at risk of acquiring HIV or other infections in their professional activities in two settings: (1) during the patient examination, and (2) during surgery. OSHA regulations do not apply to the personal conduct of the self-employed ophthalmologist, only to the conduct of staff. Therefore, the ophthalmologist may elect to be less stringent in personally following these precautions, which, however, is not recommended. Not taking these precautions must come with the ophthalmologist's full understanding that this may increase the risk of becoming infected.
|GENERAL OFFICE PRECAUTIONS|
The hands should be washed with soap and water and thoroughly dried on a fresh or disposable towel after each eye examination. Fingernails should be kept short and clean. The hands and fingers should be inspected frequently for cuts, abrasions, breaks in the skin, or paronychia. Ophthalmologists should avoid touching their own eyelids or contact lenses with their fingers without thorough hand washing.
In accordance with these recommendations, disposable gloves should be readily available for all health care workers, who should be instructed regarding the rationale for wearing gloves and their appropriate use. Notice that gloves are not a substitute for hand washing, and they are for single use only and should be discarded after each patient encounter.
GOWNS AND MASKS
Gowns and masks are unnecessary in the normal ophthalmic office setting.
PROTECTIVE EYE WEAR
Protective eye wear normally is unnecessary except in situations in which splashing with blood or blood-contaminated fluids may be anticipated.
When assisting in the examination of eye patients, health care workers may be required to handle the eyelids and surrounding facial skin and thus may come in contact with tears and the conjunctival membrane. To minimize direct contact with these tissues, particularly if the patient has a known eye infection, health care workers should be instructed in the use of gloves or in the “no-touch” techniques involving the use of cotton-tipped applicators to stabilize the tissues when possible.
HEPATITIS B VACCINATION
Health care workers who frequently come in contact with needles, blood, or blood products are advised to receive hepatitis B vaccine to avoid infection with the virus.14
According to CDC recommendations, all health care workers should be aware and adopt precautions to prevent injuries caused by needles, scalpels, and other sharp instruments or devices during procedures, and to prevent injuries that occur when cleaning used instruments, during the disposal of used needles, and when handling sharp instrument after procedures.
To prevent needle-stick injuries, health care workers should be instructed in the proper handling of needles; that is, needles should not be recapped, purposely bent or broken by hand, removed from disposable syringes, or otherwise manipulated by hand. Health care workers should be instructed to place disposable syringes and needles, scalpel blades, and other sharp items in puncture-resistant containers after their use. Puncture-resistant containers should be provided, and they should be located as close as is practical to the area where needles and syringes are used.
Photographers and other health care workers who come in contact with blood while performing fluorescein angiography should wear gloves and adhere to the procedures just outlined.
CONTACT LENS FITTING
Health care workers involved in the fitting of contact lenses should be instructed in the precautions outlined by the CDC discussed earlier.
MINOR SURGERY AND DIAGNOSIS
Universal precautions should be observed during the performance of minor surgical and diagnostic procedures. Particularly where contact with blood or blood-contaminated fluids may occur, disposable gloves should be worn. Masks and protective eye wear also should be worn if splashing of these materials is anticipated.
Ophthalmologists are probably most at risk of exposure to HIV and other more infectious diseases through mishaps in surgery. The following procedures are recommended during eye surgery:
Health care workers assisting with eye surgery should be instructed to avoid the direct handling of needles and those parts of instruments that have come into contact with body tissues and fluids. Thus, needles and sutures should be manipulated with forceps rather than by the gloved fingers, instruments should be held by the handle rather than by the tips, and the cleaning of instruments should be performed in such a way that accidental perforation of the gloves is avoided. If an instrument punctures the skin of a health care worker, it must be removed from the operating field and sterilized. The assistant must reglove as soon as possible after such an accidental injury occurs, after all bleeding has stopped and any residual blood has been removed. These practices should be incorporated into standard operating room infection control and should be monitored for compliance.
The literature reports on aerosolization of infectious viral particles after excimer laser surgery of the cornea.16 The carbon dioxide laser also has been implicated as a cause of papillomavirus infection in its surgical operators.16 It is well known that the excimer laser tissue ablation creates a gaseous cloud or plume. In theory, infectious viral particles may be transmitted in that plume. Reports in the literature are conflicting, however. Moreira and coworkers16 found viable herpes simplex and adenovirus growth on culture plates covered with a cell monolayer after excimer ablation of an adjacent viral infected plate. The maximum distance appeared to be 3.5 cm. Most of the inoculation was in the direction of the vacuum evacuation. The spread also was dependent on the amount of infectious particles at the ablation site. In general, the levels necessary for adjacent spread were higher than the titers thought to be present in the human cornea or tear film. In direct conflict with this report, Hagen and coworkers17 found no viral transmission of a pseudorabies virus onto uninfected plates located inverted 3.5 cm above the lasered virus-infected plates. Taravella and coworkers18 found similar results in that no viable viral particles survived excimer ablation using attenuated varicella-zoster virus.
Although a theoretical risk of viral transmission exists with the excimer laser plume, it is generally believed to be small. There have been no reports of known clinical transmission of any virus when using the excimer laser. Nonetheless, precautions should be taken on all patients. Herpes simplex virus, adenovirus, and human immunodeficiency virus all have been found in corneal cells and the tear film. Hardier viruses, such as the hepatitis virus, may have a greater likelihood of transmission by this method. It is recommended that all personnel involved in the laser procedure wear masks and gloves and that there be vacuum evacuation of the plume directed away from the surgeon.16 It also is recommended that the surgeon hand wash between laser cases.18
|POSTEXPOSURE PROTOCOL AND CHEMOPROPHYLAXIS|
|The blood-borne pathogen standards of OSHA19 mandate that there be a system in place for prompt evaluation and counseling
when a health care worker has had an at-risk exposure to HIV. The
patient's status, if unknown, should be obtained as soon as possible
after the the exposure. If the patient is HIV positive or refuses
testing, the health care worker should be tested as soon as possible
and again at 6 weeks, 12 weeks, and 6 months if results are negative. The
provider needs to be counseled to refrain from at-risk behavior
during the 6 months after the procedure.|
The Center for Disease Control and Prevention and the International AIDS Society—USA has set forth recommendations for chemoprophylaxis after occupational exposure to HIV infection.20–22 Because viral replication is believed to be rapid, chemoprophylaxis should be initiated immediately or as soon as possible after the exposure. Although many uncertainties remain, such as how quickly treatment should be initiated and for how long, it has been shown clinically that chemoprophylaxis with zidovudine after exposure decreases the likelihood of viral transmission.23,24 In addition, since combination therapy is more effective for treatment of patients with HIV, the Center for Disease Control and Prevention21 recommends nucleoside analogues zidovudine and lamivudine along with idinavir, a protease inhibitor. The International AIDS Society—USA22 recommends using two drugs not used in the source patient, such as nucleoside analogues stavudine and didanosine, to limit resistance potential. They have even advocated the use of nonnucleoside reverse transcriptase inhibitors if needed.20,22
In summary, the individual circumstances of the exposure should be considered in the decision to treat a patient after occupational exposure. These include viral load and CD4 count of the source patient, the method of exposure (percutaneous, mucous membrane, skin), and the medium of the exposure (blood, tears, urine). The recommendation for a standard regimen includes zidovudine, 200 mg every 8 hours on an empty stomach, with lamivu-dine, 150 mg every 12 hours, and indinavir, 800 mg every 8 hours, also on an empty stomach.20–22
|PATIENT AND HEALTH CARE PROVIDER PROTECTION SUMMARY|
|The risk of contracting HIV infection in the ophthalmic health care setting is judged to be remote. There is no evidence that the virus can be acquired from tears. Although HIV has been isolated from tears, the small amount of virus present is considered by most authorities to be below an inoculating dose. The measures outlined earlier may therefore be judged by some to be unnecessarily stringent. However, remember that these are effective precautions against other more infectious agents that may be encountered in patients with AIDS. It is also true that most nonphysician health care workers assisting in delivering eye care have only a minimal knowledge of infectious processes and their control. Their safety is addressed under the guidelines issued by OSHA.|
|RESPONSIBILITIES TOWARD PATIENTS WITH KNOWN OR SUSPECTED HUMAN IMMUNODEFICIENCY VIRUS|
|As with all physicians, ophthalmologists have a moral and ethical responsibility
to provide care to all patients, regardless of whether they
are known to be infected with the HIV or fall within a
“high-risk” group. A clinician may elect to take additional
precautions when treating such patients but may not withhold appropriate
care. (A prudent clinician uses the same precautions for all patients.)|
By taking reasonable precautions, ophthalmologists and eye care personnel are at little risk of contracting HIV or other types of infection during routine clinical practice. The risk may indeed be lowest of all when dealing with known HIV carriers, since the ophthalmologist is readily reminded that appropriate precautions are in order. Seropositive patients without clinical AIDS pose a greater, if only theoretical, risk because they are more numerous and generally are unaware of their infection.
3. Joint Advisory Notice: Protection Against Occupational Exposure to Hepatitis B Virus (HBV) and Human Immunodeficiency Virus (HIV). Washington, DC: US Department of Labor, Department of Health and Human Services, October 19, 1987
4. Centers for Disease Control: Universal precautions for prevention of transmission of human immunodeficiency virus, hepatitis B virus and other blood-borne pathogens in health-care settings. MMWR 37:377–378, 1988
14. Occupational Safety and Health Administration: OSHA Final Standards for Occupational Exposure to Bloodborne Pathogens: Code of Federal Regulations 1910, p 29. Vol 6. Occupational Safety and Health Administration, Washington, DC, 1996
23. Centers for Disease Control and Prevention: Case-control study of HIV seroconversion in health-care workers after percutaneous exposure to HIV: France, United Kingdom and United States, January 1988-August 1994. MMRW 44:929–933, 1995