Hearing impairment and otosclerosis: Nursing

Hearing impairment refers to partial or total loss of hearing. There are three types of hearing loss: conductive hearing loss, which occurs when there’s an obstruction of sound wave transmission; sensorineural hearing loss which occurs when the inner ear or auditory nerve is damaged; and mixed hearing loss which is a combination of the two.

Let’s start with the normal physiology of hearing. The ear is made up of three parts: the external, middle, and inner ear, all of which help process air vibrations as sound.

The main role of the external and middle ear is to transfer and amplify sound, while the inner ear also plays a role in balance.

Let’s start with the external ear, which is by far the most common anatomical spot to hang earrings from. The external ear is actually a complex structure made of the auricle, also called the pinna; and the external acoustic meatus.

Now, at the end of the external acoustic meatus, there’s the thin, oval tympanic membrane, more commonly known as the eardrum, which separates the external ear from the middle ear.

When sound waves hit the tympanic membrane, it vibrates and transfers the vibration to the middle ear. The middle ear, also called the tympanic cavity, is a tiny chamber found in the petrous part of the temporal bone, and it houses the three auditory ossicles, called the malleus, incus and stapes, which are the three smallest bones in the body.

These ossicles create a chain that connects the tympanic membrane to the oval window to transfer and amplify air vibrations into the inner ear to be processed as sound.

Now, the inner ear contains the bony labyrinth, which contains cavities filled with perilymph, and the membranous labyrinth, which is made of sacs and ducts suspended in the bony labyrinth.

A part of the inner ear called the cochlea contains the sensory cells for hearing. Now, sound waves travel from the air, through the ear canal, and hit the tympanic membrane, causing it to vibrate.

The vibrations are then transferred through bony ossicles to the oval window which makes waves in the perilymph. The waves travel through the fluid of the inner ear and are picked up by the sensory cells, which create nerve impulses that travel through the vestibulocochlear nerve, which is cranial nerve VIII, to the brain.Now, the causes of hearing loss depend on the type.

Conductive hearing loss is most commonly caused by an obstruction of the external canal with debris, wax, or foreign bodies.

Other causes include perforation of the tympanic membrane, acute otitis media, a defect in the ossicles of the middle ear due to head trauma, and presbycusis, which is a fancy way of saying hearing loss caused by aging.

Presbycusis typically begins with loss of high frequency sounds and eventually progresses to involve all frequencies. Conductive hearing loss can also be caused by otosclerosis, which is a genetic disorder of the middle ear that causes a bony overgrowth of the tissue surrounding the ossicles, impairing vibration transmission.

Sensorineural hearing loss, on the other hand, is caused by impaired function of the inner ear, cochlea, or the vestibulocochlear nerve.

Sensorineural hearing loss can be caused by congenital disorders, in utero rubella infections, trauma of the inner ear, constant exposure to loud noise, acoustic neuromas, otosyphilis, and some medications such as aminoglycosides.Finally, clients with mixed hearing loss have blockage in the outer ear along with damage to the inner ear.

Conductive hearing loss is when obstructions in the external or middle ear cause problems transferring soundwaves, so they don’t reach the inner ear and the sensory cells.

On the other hand, sensorineural hearing loss impairs the transfer of stimuli to the brain. Now, the early signs of hearing loss are answering questions inappropriately or not responding when called.

Other signs include straining to hear, cupping the hand around the ear, reading lips, and an increased sensitivity to noise.

Conductive hearing loss is usually sudden and in this case the client speaks softly because their own voice seems loud. They also hear better in a noisy environment.

With otosclerosis, the conductive hearing loss is slowly progressive and it’s usually bilateral. Clients with otosclerosis have a ringing or roaring type of constant tinnitus and they hear loud sounds in the ear when chewing.

Sensorineural hearing loss is usually progressive and in this case, clients speak loudly and hear poorly in loud environments.

It’s also more commonly associated with tinnitus and, occasionally, with dizziness. Let’s move on to the diagnosis of hearing loss which is based on signs and symptoms, otoscopic examination, tuning fork tests such as the Rinne and Weber Tests, imaging studies such as X-ray, CT, MRI, and audiometry.

The otoscopic examination is done in order to determine the patency of the external canal, identify lesions or excessive cerumen in the canal, and assess whether the tympanic membrane is intact or inflamed.

In conductive hearing loss, the otoscopic examination may show evidence of obstruction or abnormalities in the tympanic membrane, while in sensorineural hearing loss, the external canal and the tympanic membrane are unaffected.

The Weber and Rinne tuning fork tests are useful screening tests that determine whether the hearing loss is conductive or sensorineural.

With the Weber test, a tuning fork is struck and then placed on the vertex of the client’s head. A normal result is when the tuning fork is heard equally in both ears.

In conductive hearing loss, the tuning fork will be heard louder in the affected ear, while in a sensorineural hearing loss, the tuning fork will be heard louder in the unaffected ear.

On the other hand, the Rinne test can only detect the presence of conductive hearing loss. First, a struck tuning fork is placed on the mastoid process and the client can hear the sound conducted through the mastoid bone.

Under normal conditions, bone conduction is worse than air conduction, so once they stop hearing the sound from the tuning fork, move it immediately 1 cm away from the ear, and they should still hear the sound via air conduction; this is called a positive result.

However, if there’s a problem with the middle ear, the client wouldn’t hear the tuning fork next to their ear and this is called a negative result.

Imaging studies can be done to assess some lesions that lead to hearing loss. So, skull X-rays can determine the bony involvement in otitis media, as well as the location of the otosclerotic lesions, while CT and MRI may be used to determine soft-tissue involvement and the presence and location of tumors.

Audiometry can confirm the presence of hearing loss and quantify its severity. Finally in infants, hearing loss can lead to delays in speech, language and cognitive development.

Early intervention can decrease this delay, but it’s only effective if started before the age of 6 months. This is why often, newborns are screened for hearing impairment before they even leave the hospital.Finally, treatment depends on the type of hearing loss and the underlying cause.

So, with conductive hearing loss, treatment usually consists of removal of foreign objects and cerumen, and treating the tympanic membrane perforation and infections.

A myringoplasty can be done, which means surgically correcting a perforated eardrum. In case of otosclerosis, the treatment can be non-surgical with hearing aids or surgical, by stapedectomy which is removing the bony growth around the ossicles or by ossiculoplasty which involves surgical reconstruction of the ossicles.

Sensorineural hearing loss should be treated according to the underlying cause, and if it’s associated with permanent hearing loss, assistive devices can be used, such as hearing aids or cochlear implants.Alright, let's talk about the nursing care you’ll provide for a client with hearing impairment.

Your primary nursing goal is to communicate with your client effectively. If their hearing loss can be improved or corrected with surgery, then you will also have the goal of providing supportive postoperative care.

Focus your assessment on determining how to best communicate with your client. Review the results from their hearing tests and observe their behavior for specific signs of hearing impairment such as cupping their hand to their ear or not responding when spoken to.

Pay particular attention to their ability to hear high frequency consonants, such as s, f, sh, th, and ch, and adjust your speech accordingly.

Be sure to use techniques such as positioning yourself directly in front of them, speaking slowly, and using hand motions as appropriate.

Asking them to repeat important information can also help ensure they have understood correctly. Now, if your client has undergone a surgical procedure to correct their hearing impairment, provide routine postoperative care, and assist them to lay flat with their head turned so the operative ear is facing upwards.

Cranial nerves VII, VIII, and X, as well as inner ear structures can be affected by trauma or swelling during some surgical procedures, so assess your client for an asymmetric drooping of the face, changes in sensation, vertigo, and nausea.

Administer the prescribed antiemetics and antivertiginous medications, as needed. Next, observe the gauze packing or surgical dressing for excessive bleeding or drainage, and be sure to use sterile technique if a dressing change is needed.

Your client may also apply a glasscock dressing, which is a special concave dressing that provides protection as the ear heals.

Also, administer the prescribed antibiotics and analgesics. Report to a healthcare provider immediately if the client has excessive bleeding, pain unrelieved by analgesics, or abnormal vital signs.

Okay, let’s move on to client and family teaching. Begin by helping your client learn about how their hearing impairment occured, review the plan of care for supporting their hearing, and remind them of the importance of going to all follow up appointments.If your client underwent a surgical procedure, provide teaching on caring for themselves at home.

Reassure them that due to bulky dressings and postoperative swelling, they may not notice an improvement to their hearing for several days or weeks after the procedure.

Then, teach them to avoid damage to their ear by avoiding activities such as straining when having a bowel movement, coughing forcefully, bending over, rapidly moving their head, or bouncing.

When they need to blow their nose, instruct them to blow gently with their mouth open. Lastly, teach them to take their postoperative medications and change their dressing exactly as directed, and to let their healthcare provider know right away if they notice excessive drainage, or if they develop a fever, chills or any new symptoms.Now, if your client has a hearing aid, teach them how to properly care for the device, including how to properly clean and store it; how to change the battery; and to remember to turn it off when not in use.

For all clients, teach them how they can decrease the risk of ear infections or trauma. Instruct them to never put small objects such as cotton-tipped applicators, toothpicks, or keys into their external ear canal; teach them to wash their external ear daily while showering or bathing; remind them to routinely clean objects such as telephones, headphones, or earbuds; stress the importance of avoiding exposure to loud noises; and lastly, remind them to keep their mouth open when sneezing or blowing their nose.Hearing impairment is the partial or total inability to hear.

It can be either conductive, sensorineural, or mixed- which is a combination of the two. Conductive hearing loss occurs when there is an obstruction of sound wave transmission, like a buildup of wax or a foreign body in the ear canal.

On the other hand, sensorineural hearing loss is caused by impaired function of the inner ear, cochlea, or vestibulocochlear nerve.

Diagnosis can be done based upon the client’s symptoms, by an otoscopic examination, tuning fork tests, audiometry, or imaging such as X-ray, CT, or MRI.

Two tests, called the Weber and Rinne tests, can help distinguish between conductive and sensorineural hearing loss. Treatment of hearing loss depends on the cause.

This may include treating an ear infection or tympanic membrane perforation, removing cerumen buildup, getting hearing aids, or having a surgical procedure, like a myringoplasty or a stapedectomy.

Common symptoms include not responding when spoken to, cupping their hand to the ear, speaking loudly, and asking for things to be repeated.

Goals of nursing care include effectively communicating with your client and providing supportive postoperative care. Client and family teaching centers around self-care at home, proper care of hearing aids, and ways to avoid ear trauma and infection.