Julie K. Purdy, Ph.D. CCC-A, FAAA
Starkey Labs, Canada
7310 Rapistan Court
Mississauga, ON L5N 6L8 Canada
1-800-387-9353
INTRODUCTION:
A decade has passed since the American Speech-Language Hearing Association (ASHA) issued their "Position Statement on External Auditory Canal, Examination and Cerumen Management". Many other audiology organizations have followed suit, including the American Academy of Audiology (AAA) and the Academy of Dispensing Audiologists (ADA) and the Canadian Speech-Language Hearing Association.
During this same time period, the number of audiologist-provided services requiring a clean ear canal have increased dramatically, including; impedance audiometry, electronystagmography, real-ear measurements, otoacoustic emissions, electrocochleography, deep ear impressions, hearing aid fittings and noise/swim/musician earplugs.
Even with full endorsement by professional audiology organizations and concomitant scope of practice statements which permit appropriate cerumen management, the vast majority of audiologists remain hesitant to actively remove cerumen from their patient's ear canals.
Part of this hesitancy is due, I believe, to a lack of proper training and experience. However, I also believe physician-driven management practices established in the 1940's (when physicians were the gatekeepers for hearing health care) are also somewhat responsible for this situation. Of course, both of these situations are changing and improving, and therefore, it is timely to address issues related to cerumen management.
Currently, patients come to see us before seeing their physicians and sometimes, in place of their physicians. Patients expect us to perform basic and complicated tests, which require a clean ear canal. It is that simple. It is time to cast off the practice model that no longer works for the patient, the audiologist or the health care delivery system. We need to rid ourselves of the notion that only physicians can remove cerumen and we need to emerge as independent professionals who competently and safely remove earwax from the ear canals of our patients.
OVERVIEW:
Cerumen is a combination of secretions from the cerumenous or aprocrine glands and sebaceous glands. These glands are housed within the cartilaginous section of the human ear canal. The chemical composition of cerumen is fairly complex -- comprised of a mixture of lipids, protein-free amino acids and several minerals. This substance has a variety of functions attributed to it. For example, cerumen serves as a lubricant, water repellent, an anti-bacterial/anti-fungal agent and an entrapper of hair follicles, dust and insects. Whatever positive purposes cerumen may serve, when it impedes our ability to perform audiologic services required by the patient, it should be removed.
LIGHT SOURCES:
Cerumen management begins with otoscopy and illumination. Interest in viewing the ear canal began in the 14th century. The science did not progress very quickly in those days, primarily due to problems with illumination. Sir William Wilde reported the only option was to perform otoscopy using sunlight, not in the wintertime and only between the hours of 11 a.m. and 3 p.m. Later illumination options included shining a candle through a flask or water glass to concentrate the light; concentrating light with a concave mirror and in the late 19th century using a mineral oil lamp.
Today, we do not need to risk setting the patient's hair on fire with a mineral lamp, as we can take advantage of miniaturization of high intensity light bulbs, the introduction of batteries and the natural light quality resulting with halogen and fiber optic light sources. There are a variety of light source options available to use to today. The following are some of the most practical options available:
A. Electric Headlights.
The electric headlight is a great option for illumination of the ear canal for cerumen management. They come in a variety of sizes, prices and are available with and without magnification and with and without battery power options. The advantage to the headlight over other light sources is that it frees the clinician's hands. I prefer the highly concentrated halogen headlight systems as they tend to concentrate the light and do not generate much heat. While the cordless systems are handy, the corded units have the advantage of maintaining a constant bright light source.
B. Otoscope Overview.
When it comes to cerumen removal, all otoscopes are not created equal. While any otoscope may work, there are several types of otoscopes which are superior for this task. One of my favorites is the Hotchkiss otoscope. The wide bore allows a large range of motion with instruments, while the bore tends to hold the ear canal open, which frees the second hand to manipulate and manage the cerumen management tool being used.
C. Operating Microscope.
The operating microscope allows cerumen removal with superb magnification and illumination while facilitating maximal freedom for managing and manipulating tools. Unfortunately, microscopes of this quality are very expensive, and are rarely found outside of an ENT office as they are typically too expensive for the average audiologist in a private practice situation.
D. Pneumatic Otoscopes.
The pneumatic otoscope can have part of its magnification panel slide to the side, but pneumatic and conventional otoscopes makes better sense if the audiologist prefers to work to the side rather than through the speculum of the otoscope.
E. Electric Otoscopes.
Electric (AC) otoscopes can use any of the above described heads. There are advantages, as previously mentioned, to AC power - it consistently provides a powerful and bright light. The electric otoscope's main disadvantage is that many cords are too short, not allowing much movement by the clinician or the patient.
F. Video-otoscopes.
Video-otoscopes allow a much larger image than that obtained with hand-held otoscopes. They allow patient involvement, as the patient is able to observe and monitor the progress of cerumen removal. When attached to a VCR or a printer, video-otoscopes allow recordable documentation (photos). This can be useful to document pathology, cerumen impaction and referral rationale.
Speculum:
Of course, it is important to select the correct speculum. The speculum is the ice-cream cone shaped tool which physically contacts the patient. Cerumen tools can be used through the bore of the speculum or around the side. When working through the speculum, the largest diameter available provides the greatest amount of maneuvering room. Similarly, when working to the side of the speculum, the smallest diameter provides the same advantage.
While we typically use less expensive, disposable plastic speculum for most of our otoscopy, stainless steel speculum concentrates light more efficiently. It is handy to have a few stainless steel speculum in variety of sizes on hand for wax removal. The plastic speculum are used once and disposed of and stainless steel units require sterilization between uses.
Head Mirror:
Head mirrors are popular with otolaryngologists. A head mirror is a round disk, typically about 3 ½ inches in diameter with a central aperture (hole), which is ¾ inches in diameter. The disk is actually a concave mirror, which focuses room light at about 7 ½ inches -- ideal for canal observation. The mirror will intensify and focus the light, particularly if a speculum is held in place to center the light on the cerumen within the ear canal. The head mirror's downfall is that it requires a good light source so if the examination room is dimly or unevenly lit, the result might be poor illumination.
Training:
It is recommended that anyone performing cerumen removal should be adequately and appropriately trained. I recommend that each individual involved with cerumen removal take a course on this topic and be personally mentored to obtain appropriate academic and clinical training.
Contraindications and Informed Consent:
If, after visual inspection, it is determined that cerumen needs to be removed, I recommend discussing the procedure with the patient and obtaining a written, informed consent.
The written consent should include treatment options (the audiologist removing the cerumen, referral to a physician, doing nothing, home remedies and over-the-counter remedies) and should note that injury to the ear canal with subsequent infection is possible, as is perforation of the tympanic membrane. Patients should be informed that they might become dizzy and might experience mild pain or discomfort. As part of the informed consent process, additional information should be obtained, such as a history of heart problems, use of blood thinners or aspirin, history of dizziness or diabetes and any other condition which puts the patient at additional risk. Certain conditions represent contraindications for cerumen management, such as a perforated or retracted tympanic membrane, aural drainage, temporal bone fracture, otitis externa or otitis media or any other active ear-related or systemic abnormality. Provided there are no contradictions and the patient has signed the informed consent, I proceed with the procedure. I recommend that each clinician should contact their legal counsel to be certain their informed consent form is appropriate for their situation.
Infection Control:
No review of cerumen management would be complete without an overview of infection control. Universal precautions must be applied to all audiologic procedures, but this is particularly important in the case of cerumen management -- a procedure that might introduce blood to the work environment.
A review of appropriate procedures and protocols is highly recommended.
Personal Barriers:
It is imperative that hands be washed with hospital grade liquid antibacterial soap before and after cerumen management. When running water is not readily available, no-rinse antimicrobial hand products are an option. Protective barriers must include gloves when performing cerumen management. If water is to be used and there is a possibility of spraying water, eye protection, masks and protective clothing are recommended.
Disinfection of Touch and Splash Surfaces:
Reduce the pathogenic organisms on environmental surfaces by disinfecting them. Many commercial sprays exist, and bleach/alcohol can be used. These products should be sprayed on, wiped vigorously and left wet. By planning ahead, the amount of pathogens on splash surfaces can be reduced. I use plastic-backed disposable towels, placing one on my tabletop before I begin working with a patient. I place all instruments and debris that I use on a given patient onto the one towel, which can be folded together at the end session and disposed of.
Sterilization of Critical Instruments:
The goal of sterilization is to destroy all microorganisms, including viruses, bacteria, fungi and spores, on all instruments and accessories that come in direct contact with the patient, or other personnel. While a variety of methods are available to sterilize equipment, including; steam autoclave, chemical vapor sterilization, ethylene oxide sterilization and dry heat ovens, the simplest procedure is the use of a chemical sterilant such as glutaraldehyde.
After soaking the instruments in the solution for the time recommended by the manufacturer's instructions, instruments should be rinsed with sterile water or with tap water and then spayed with a disinfection spray. These instruments can then be transferred to the clean container to be used on another patient.
A separate container which is clearly marked "dirty" needs to be available at the cerumen management site so that once the procedure is completed, dirty instruments can be safely transferred for sterilization..
Waste Management:
While it is probably safe to dispose of paper towels, speculum, gloves, etc. into regular garbage bags -- unless a significant amount of blood is present -- I recommend the use of special biohazard waste bags which are properly sealed.
Admittedly, this is probably "overkill" because, in reality, the likelihood of having significant traces of blood which could be transferred via the garbage is small - but, as I have taken precautions to protect myself during the procdure, even if the risks are slight, I believe I should protect those who remove trash from my building as well.
Cerumen Management: Getting Started:
The patient and clinician must be seated comfortably. The patient should be seated in a comfortable chair and they should be appropriately draped so their clothes do not become splattered with water or debris. The audiologist must be able to sit comfortably too. We need to sit slightly elevated from our patient and to be able to rest comfortably on the patient's shoulder. A small, backless, swivel stool works well as it can be raised or lowered to a comfortable level. Once both parties are comfortable, the removal process can begin.
Several cranial nerves rest in the area of the ear canal, namely the posterior auricular branch of the facial nerve, the auriculotemporal-branch of the trigeminal nerve and the auricular branch of the vagus nerve. Consequently, certain reflexes can be triggered via cerumen management. The most common are coughing, sneezing, gagging, vomiting, fainting, unconsciousness, cardiac depression and dizziness.
Coughing is the most common reflex to be triggered via this process and fortunately, unconsciousness and cardiac depression are uncommon. Nonetheless, we must be prepared to address these situations should they occur. Emergency protocols should be clearly established.
Cerumen Management Tools:
We next determine which tools we wish to use. As I prefer to remove wet and pliable cerumen, I often begin with irrigation. Others prefer to use suction, and still there are those who prefer to just remove cerumen with specific instruments. It really is personal preference and safety that guides these decisions, provided the patient is comfortable with the methods selected.
Historically, tools of choice included steam, goat or cow urine or even candling. I have yet to try any of these historical methods -- primarily due to the fact that we know candling is very dangerous and doesn't work, and I have yet to find anyone who would consent to having goat or cow urine poured in their ear (in addition, I wasn't sure how I would gather the urine).
I prefer to select from the following tools: irrigation, hand held cerumen instruments, suction and cerumenolytics. Literally hundreds of products are available for cerumen management, and the following is a general list only.
Irrigation Products:
Irrigation products can range from simple products such as bulb or metal syringes with plungers and removable cannula, to sophisticated products, such as the Welch-Allyn Earwash system which connects directly to a faucet, monitors water temperature and suctions the water and cerumen from the ear. Other products such as the "Water Pik" with or without specially designed ear tips, or the portable Biocare which allows for water direction towards the ear canal wall are also available.
Each product, from low-tech bulb syringes to high-tech wash systems, allows us to introduce water into the ear canal and flush the cerumen from the canal or to moisten the cerumen so it can be removed. In all cases an emesis basin is necessary to collect the runoff water. I usually have the patient hold the basin under the ear while I am irrigating. Most patients startle or jump when the wated flow starts. It the patient has accepted the role of holding the basin and then they pull away and water dribbles (or gushes) down their necks, they tend to be more forgiving of themselves than they might be if you were holding the basin!
If the irrigation water or saline is not at, or close to body temperature, the patient may become dizzy via the same mechanism as the caloric irrigation during an electronystagmography test. Warming the irrigation fluid to body temperature usually eliminates this problem. Importantly, water temperature must be carefully monitored to insure a constant temperature which does not burn the patient, and which minimizes the potential for a caloric response.
Instruments:
A variety of stainless steel surgical hand tools are available for cerumen removal. These tools range from $20.00 to 50.00 a piece. They come in many shapes and sizes. The most popular are the rounded Buck Curette, an oblong Shapleigh Curette, and a thin looped Billeau Curette. Each of these can be used to lightly scrape or scoop pieces of soft wax from the ear canal. Each comes in a variety of sizes. The Lucae ear hook has a 90-degree angle and a point. Another useful tool is the aural forceps, these are available in a pointed version (alligator) or a rounded version (cupped) and can be used to pick large pieces of cerumen or foreign bodies from the ear canal.
Many of the surgical steel tools mentioned above are available in plastic, disposable versions, such as those manufactured by Bionix. Plastic tools are less expensive and have a great degree of flexibility, making them a popular alternative to purchasing more expensive, surgical steel versions.
Cerumenolytics:
A variety of "home-made" products can be used to soften earwax. The most common concoctions include carbon peroxide mixed with glycerin, hydrogen peroxide mixed with baby or mineral oil, olive oil, distilled water, sodium bicarbonate and colex liquid (which can be obtained from a pharmacist). Most commercially available eardrops such as Audiologist's Choice or Murine drops are comprised of Carbomide peroxide and glycerin. The advantage of these products is similar to the advantages obtained via irrigation: they soften cerumen, making it easier to remove via hand tools, water or suction. Drops can be placed in the office, allowed to "work" for 10 to 15 minutes, and then other methods can be pursued to remove the wax.
Suction:
A variety of aural suction devices are available. While many of these units allow quick removal of cerumen, there are some disadvantages. Namely, the design of the suction tips are typically long and pointed. Should a patient "jerk" during the process, it is difficult to adequately brace the patient's head or shoulder, which arguably makes them dangerous. In addition, suction units are somewhat costly and fairly noisy. Additionally, noise created by the suction and perceived by the patient, can be disturbing.
Conclusion:
A Few Final Points, In Summary
When I first began to manage cerumen, I would only work with about half of the ears I saw. I started with the easy patients and as I gained confidence, I moved on to more difficult patients. Now, through a combination of tools, suction, cerumenolytics and irrigation, I can typically remove cerumen from 90% of the patients I see.
I could probably increase this percentage if I wished but in the end, I hope that my patients will like me and I want to come back and see me. This is easier to insure if I do not hurt my patients! I determine if the cerumen is too adhered to the canal wall or if the wax has shifted into bony section - I still refer those patients on to an otolaryngologist.
I am not apologetic if I am unable to do the job. I know that I am significantly less well covered by my malpractice insurance than the average otolaryngologist, and I know that I am not a physician! I also firmly adhere to the policy of "first, do no harm."
In the final analysis, cerumen removal is a simpler process than this description (above) might imply. Most of the clinical procedures we do daily as professionals are far more complicated than cerumen removal. Therefore, I encourage the reader to learn more about the topic, study the topic, and to develop an expertise based on clinical, academic and practical experience, while always working within the limits of their Scope of Practice, their training and their competence.
SUGGESTED READINGS and REFERENCES:
Ballachanda, B. & Peers, C. (1992) Cerumen management: instruments and procedures. ASHA: 34: 43-46.
Ballachandra, B. (1993). Cerumen management: causes of impaction, steps for removal. Hearing Instruments: 44(9), 30-33.
Grahl, C. (1993). Cerumen management: is it in your future? Hearing Instruments: 44(4): 8-14.
McMillian, M. & Willette, S. (1988). Aseptic technique: a procedure for preventing disease transmission in the practice environment. ASHA: 35-37.
Ballancandra, B., Roeser, R. & Kemp, R. (1996). Control and prevention of disease transmission in audiology practice. American Journal of Audiology:
5(1), 74-82.
Cohen, M. & McCollough, T. (1996). Infection control protocols for audiologists. American Journal of Audiology: 5(1), 20-22.
Sullivan, R. (1995). Audiological applications of video otoscopy. The Hearing Journal: 48(8), 2-7.
Hawke, M. (1987). Clinical Pocket Guide to Ear Disease. New York: Gower Medical Publications.
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Managing Cerumen
September 3, 2002
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