External Ear Obstructions
(Ear Foreign Body)
The ear canal may be obstructed by cerumen (earwax), a foreign object, or an insect. Itching, pain, and temporary conductive hearing loss may result. Most causes of obstruction are readily apparent during otoscopic examination. Treatment is careful manual removal.
Before and after attempting to remove cerumen or a foreign body, clinicians should consider doing a hearing assessment if they have the necessary equipment readily available. Hearing loss (compared to the unaffected ear) that does not improve after removal of the obstruction could indicate that the foreign body (or prior attempts to remove it) has damaged the middle or inner ear. Hearing that worsens after removal of the obstruction could indicate damage caused by the removal process. However, practitioners who cannot formally assess hearing need not defer removal of common, easily removable obstructions. An in-office tuning fork test may also document hearing status.
Cerumen may be pushed farther into the ear canal and accumulate during patients' attempts to clean the ear canal with cotton swabs, resulting in obstruction or impaction. Cerumen solvents (hydrogen peroxide, carbamide peroxide, glycerin, triethanolamine, liquid docusate sodium, or mineral oil) may be used to soften very hard wax before direct removal. However, the prolonged use of these agents may lead to canal skin irritation or allergic reactions.
Cerumen can be removed by rolling it out of the ear canal with a blunt curet or loop or a small right angle hook, or by removing it with a suction tip (eg, Baron, size 5 French). Proper lighting is essential. These methods, particularly when done by an experienced practitioner, can be quicker, safer, and more comfortable for the patient than irrigation. Irrigation is often done in the emergency department or primary care setting and should be done carefully to avoid complications. Irrigation may also be combined with cerumenolytic agents, such as docusate sodium. Irrigation is contraindicated in patients with a known tympanic membrane perforation. Water entering the middle ear through a tympanic membrane perforation may exacerbate chronic otitis media and cause an acute otitis media.
Foreign bodies are common, particularly among children, who often insert objects, particularly beads, erasers, and beans, into the ear canal. Foreign bodies may remain unnoticed until they provoke an inflammatory response, causing pain, itching, infection, and foul-smelling, purulent drainage.
In general, foreign bodies that appear easy to grasp and remove (eg, paper, an insect wing) can be removed with alligator forceps by most practitioners. However, forceps tend to push round, smooth objects (eg, beads, beans) deeper into the canal. Patients with such objects should be referred to an otolaryngologist. A smooth, rounded foreign body is best removed by reaching behind it and rolling it out with a small, blunt hook, which should be done under operating microscope guidance by a specialist. Without a microscope, a foreign body lying at or medial to the isthmus (the bony cartilaginous junction of the external auditory canal) is difficult to remove without injuring the delicate canal skin, tympanic membrane, or ossicular chain. Referral to an otolaryngologist also is indicated for an uncooperative child, who may require sedation, or for failed attempts at removal.
A general anesthetic or deep sedation may be needed when a child cannot remain still or when removal is difficult, threatening injury to the tympanic membrane or ossicles. Further, if manipulating a presumed foreign object results in bleeding, further attempts at removal should stop and immediate otolaryngologic consultation should be sought. Bleeding may indicate a laceration of the canal skin or that the foreign body is actually a middle ear polyp.
Insects in the canal are most annoying while alive. Filling the canal with viscous lidocaine kills the insect, which provides immediate relief and allows the immobilized insect to be removed with forceps by grasping a wing or leg.