Meniere disease: Nursing
Transcript
Ménière disease is a progressive condition that affects the inner ear, and can lead to episodes of vertigo, tinnitus, and hearing loss.
Now, the ear is composed of three main parts. The first part is the outer ear, which includes the visible part of the ear, called the pinna or auricle, as well as the ear canal. The second part is the middle ear, which is a tiny chamber that houses even tinier ear bones. And the third part is the inner ear, sometimes called the labyrinth, which can be further divided into three parts. The central part is the vestibule, which is connected to the other two other parts; the semicircular canals, towards the back, which play a role in balance, and the cochlea, towards the front of our head, that deals with hearing.
Now, the cochlea is the part involved in hearing, and is lined by small hair cells and filled with fluid called endolymph. When sound reaches the cochlea, the endolymph vibrates, causing the hair cells to vibrate. As a result of this vibration, the small hair cells fire off electrical signals conveying sound to the brain, allowing for the processing of hearing. On the other hand, the semicircular canals are involved with balance. These canals are also lined by hair cells and filled with endolymph. So, when the head moves, the endolymph inside the canals sloshes in one direction and makes the hair cells move, causing them to fire off an electrical signal conveying the direction and speed of the head movement. This signal is then carried to the brain, allowing for the processing of balance.
Now, the cause of Ménière disease is unclear, but risk factors seem to include genetic predisposition and family history; a viral infection or autoimmune reaction involving the inner ear; and abnormal flow or resorption of endolymph, which can be due to an obstruction or congenital malformation of the inner ear.
Okay, so in Ménière disease there’s excessive accumulation of endolymph in the inner ear, which is known as endolymphatic hydrops. This puts pressure on the sensory receptors of the cochlea and the semicircular canals, causing damage over time.
Clients with Ménière disease typically present with a classic triad of symptoms including vertigo or feeling dizzy and off balance, as well as tinnitus or ringing of the ears, and hearing loss. These symptoms typically come in episodes that start abruptly and may last from 20 minutes up to 12 hours, and can be triggered by high dietary salt intake, monosodium glutamate, caffeine, alcohol, and nicotine, as well as emotional stress, infections, or allergies.
Ménière disease tends to progressively worsen with each episode, and over time, it might result in permanent hearing loss. Moreover, most cases affect only one ear, but as the disease progresses, it can extend to affect both ears. Clients often also experience a feeling of ear fullness and pressure. Additional signs and symptoms can include headaches, nausea, and vomiting. Lastly, Ménière disease can interfere with the client’s activities of daily living, such as working or driving.
Now, the diagnosis of Ménière disease starts with history and physical assessment, where an audiometry test can be done to assess hearing loss.
There’s no cure for Ménière disease, so treatment aims to reduce the number and severity of episodes, as well as prevent disease progression. Initial treatment is focused on lifestyle changes to minimize exposure to triggers, such as limiting dietary salt intake, caffeine, alcohol, and nicotine, as well as reducing emotional stress. In addition, some clients can be referred to vestibular rehabilitation therapy, which consists of exercise activities to reduce vertigo and dizziness, and improve balance.
If symptoms persist despite lifestyle modifications, clients can be treated with medications like betahistine, or diuretics containing hydrochlorothiazide or acetazolamide. If symptoms still persist, clients can also be treated with oral or intratympanic glucocorticoids to reduce inner ear inflammation; or intratympanic gentamicin injection to destroy hair cells in the semicircular canals. Finally, clients who don’t respond to any of these options can be treated with surgery, such as endolymphatic sac decompression surgery to drain the excess endolymph, or in the most severe cases with permanent hearing loss, a labyrinthectomy can be performed, where the labyrinth is removed.