Understand the etiology, pathophysiology, and clinical manifestations of both acute otitis externa and necrotizing otitis externa.

  Identify the prototype and describe the action, use, adverse effects, contraindications, and nursing implications for topical medications used to treat otitis externa.

  Identify the prototype and describe the action, use, adverse effects, contraindications, and nursing implications for systemic medications used to treat necrotizing otitis externa.

  Identify the prototype and describe the action, use, adverse effects, contraindications, and nursing implications for systemic medications used to treat otitis media.

  Identify the adjuvant drugs used to treat otitis externa and otitis media.

  Implement the nursing process in the care of the patient with otitis externa or otitis media.

KEY TERMS

Otalgia: ear pain

Otic: relating to the ear

Otitis externa: inflammation of the external ear that occurs as a mild allergic dermatitis or as a severe cellulitis

Otitis media: inflammation of the middle ear

Otorrhea: purulent ear drainage

Introduction

This chapter discusses some ear-related disorders and their pharmacological treatment. Infections, whether bacterial or fungal, or allergic reactions, result in ear pain-related inflammation. Otitis externa is a disorder of the external ear that produces inflammation. This condition, most commonly known as swimmer’s ear, is more likely to occur in the summer months. People whose ears are frequently exposed to moisture are more prone to the development of this disorder. Malignant necrotizing otitis externa most commonly affects elderly patients with diabetes mellitus and patients with the human immunodeficiency virus. Otitis media is an acute infection or inflammation of the middle ear. Acute otitis media is the most common ailment for which anti-infective agents are prescribed in children.

The pharmacological therapy of choice for disorders of the ear is otic preparations. These medications, which are discussed elsewhere in this book, have special uses in the treatment of ear conditions.

Overview of Disorders of the Ear

Etiology

Otitis Externa

Causes of otitis externa include moisture in the ear canal, allergic reactions such as psoriasis, or trauma of the ear canal related to itching or scratching. Pseudomonas aeruginosa, Proteus, and Staphylococcus aureus are bacteria that may play a causal role. Aspergillus is the fungus that thrives in the most ear canal.

Otitis Media

Otitis media is more common in children than adults. The causative pathogens include Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis. They enter the middle ear as a result of an alteration in the eustachian tube. This can be caused by upper respiratory congestion, inflammation, or an allergic reaction. Bacteria may enter the middle ear from the contaminated secretions of the nasopharynx or perforation of the tympanic membrane of the middle ear.

Pathophysiology

Otitis Externa

Otitis externa involves the presence of moisture in the external ear canal, leading to the development of inflammation of the pinna and canal. The canal becomes itchy, red, and tender, and increased swelling makes it narrower. Ear pain occurs with movement because of the inflammation. There may be watery or purulent drainage, and intermittent hearing loss may result (Porth & Matfin, 2009).

Necrotizing otitis externa is a soft tissue infection of the external auditory canal. The epidermis becomes thickened and inflamed and the underlying dermis exhibits chronic inflammation. Involvement of the osseous portion of the external auditory canal can lead to temporal bone osteomyelitis. The infection is progressive causing rapid debilitation. If the infection spreads to the base of the skull, it can be fatal.

Otitis Media

In otitis media, infection causes an obstruction of the eustachian tube, resulting in fluid retention and suppuration of retained secretions. This infection is more common in children because the eustachian tube is straighter, allowing the pathogen to enter the ear more easily.

Clinical Manifestations

Otitis Externa

In acute otitis externa, the patient complains of ear pain and discharge from the external auditory canal. The discharge may be yellow or green, possessing a foul odor. The patient may also report a feeling of “fullness” in the ear, decreased hearing, and pruritus.

In necrotizing otitis externa, the presenting symptoms are otalgia, or ear pain, and otorrhea, or purulent drainage. The pain is primarily experienced at night and may extend to the temporomandibular joint when chewing. The advancement of the infection results in osteomyelitis of the skull and temporomandibular joint.

Otitis Media

In acute otitis media, marked fluid and inflammation in the mucosa lining the middle ear space are present (Fig. 59.1). Otalgia and diminished hearing occur. Fever may or may not be present. An upper respiratory tract infection or seasonal allergic rhinitis commonly precedes acute otitis media. Changes in equilibrium may occur. If the tympanic membrane ruptures, patients report a reduction or relief of ear pain.

Drug Therapy

Table 59.1 lists the various drugs used to treat ear disorders.

Otitis Externa

For acute otitis externa, use of topical agents, as opposed to systemic agents, is more common. Systemic medications are indicated only if a deep tissue infection develops outside the external canal or if immunocompromised status is an issue. Topical drugs are more effective because they deliver higher concentrations of medication to the infected, inflamed tissue. The use of these agents also reduces adverse effects.

When the infection extends to the pinna, prescribers order oral anti-infective agents. For necrotizing otitis externa, the primary treatment is systemic antipseudomonal antimicrobial agents. Ciprofloxacin is the drug of choice for adults, whereas cephalexin (Keflex) is the preferred drug for children (see Chaps. 16 and 17). The otic solutions most commonly prescribed for acute otitis externa are combination solutions. These medications contain an anti-infective agent, antiseptic, glucocorticoid, and acidifying agent.

Otitis Media

Oral amoxicillin (Amoxil) is the drug of choice for the treatment of acute otitis media (see Table 59.3). Patients who are allergic to penicillins may take cephalosporins.

TABLE 59.3

DRUGS AT A GLANCE: Oral Anti-Infective Drugs

Anti-Infective, Antiseptic, Glucocorticoid, and Acidifying Agents

Health care providers use the combination drug neomycin–polymyxin B–hydrocortisone (Cortisporin Otic) for the treatment of acute external otitis media. Neomycin and polymyxin B are antibiotics, which combat bacterial infections. Hydrocortisone is a steroid, which reduces the actions of chemicals in the body that cause inflammation, redness, and swelling.

Pharmacokinetics

The metabolism and transport effects of polymyxin and neomycin are unknown. Hydrocortisone is metabolized in the liver, and excretion occurs in the urine.

Action

Each component of Cortisporin Otic has its own mechanism of action. Neomycin, an aminoglycoside, inhibits bacterial protein synthesis by irreversibly binding to the 30S ribosome of the susceptible bacteria. Polymyxin B, a miscellaneous anti-infective agent, binds to the lipid phosphates in the bacterial cell membrane, which changes the membrane permeability to prevent leakage of cytoplasm from the bacterial cell wall, contributing to cell death. Hydrocortisone, a steroid, decreases inflammation by stabilizing the leukocyte lysosome membrane, inhibiting phagocytosis and release of allergic substances.

Use

Health care providers use Cortisporin Otic for the treatment of acute otitis externa caused by P. aeruginosa, Proteus, and S. aureus. Table 59.2 presents route and dosage information for Cortisporin Otic.

TABLE 59.2

DRUGS AT A GLANCE: Anti-Infective, Antiseptic, Glucocorticoid, and Acidifying Drugs

Use in Children

Authorities recommend Cortisporin Otic in children only for bacterial infections of the external auditory canal due to the adverse effect of ototoxicity. The hydrocortisone may cause suppression of the hypothalamic-pituitary-adrenal axis in younger children.

Adverse Effects and Contraindications

Adverse effects of Cortisporin Otic include burning, stinging, and ototoxicity.

Contraindications include a known hypersensitivity to the drug’s components. Prescribers should not order it for viral, fungal, or mycobacterial infections.

Nursing Implications

Preventing Interactions

Cortisporin Otic is associated with no significant drug or herbal interactions.

Administering the Medication

Administration of Cortisporin Otic is directly in the external ear canal. Prior to administering the otic suspension, it is necessary to shake the medication well. In addition, if cerumen is present, cleaning of the ear canal with a cotton swab is important.

It is necessary to assess the tympanic membrane with an otoscope before inserting Cortisporin Otic. If the tympanic membrane is torn, then the medication is absorbed directly by the inner ear, leading to hearing loss.

The proper administration of ear drops requires tilting the head toward the opposite shoulder, pulling the superior aspect of the auricle upward, and instilling the ear drops into the ear canal. The patient should then lie on the side opposite the side of administration for 20 minutes. To maximize medication absorption, the patient should have a cotton ball placed in the ear canal.

Assessing for Therapeutic and Adverse Effects

The nurse assesses for decreased ear pain and itching as well as for decreased drainage from the ear canal.

It is also necessary to assess for signs of hearing loss due to ototoxicity. He or she also assesses for burning and stinging.

Patient Teaching

Box 59.1 lists patient teaching guidelines for Cortisporin.