(hammer), incus (anvil), and stapes (stirrup). These bones conduct vibrations from the
eardrum to the internal ear. The eustachian tube connects the middle ear with the
nasopharynx. Its principal function is to keep the air pressure equal on either side of the
eardrum. It is also the avenue of infection by which disease spreads from the throat to
the middle ear.
c. Inner Ear. The inner ear contains receptors for hearing and equilibrium. The
receptor for hearing lies within the cochlea. The cochlea is coiled and resembles a snail
shell. Sound waves, which pass through the external auditory canal, vibrate the
eardrum and ossicles, and are transmitted through the fluid of the inner ear. The inner
ear also contains three circular canals that control equilibrium.
There will be times when you should know when and when not to irrigate a
patient's ear. The information listed below will help you in making your decision.
a. Irrigation is done to cleanse the external auditory canal, to soften and remove
impacted ear wax (cerumen), to dislodge foreign bodies, to apply heat to the tissues of
the ear, and to administer antiseptics or medication.
If the foreign body in the ear is an insect that did not respond to shining light
into the ear, then you must irrigate.
b. Avoid irrigation when:
(1) Foreign matter that swells is present in the ear. The foreign matter may
be peas, corn, beans, etc. These foreign matters will increase in size as they come in
contact with water.
(2) The eardrum is punctured. Irrigation will cause additional middle ear
infection and can carry debris or discharge to the middle ear from the external auditory
EQUIPMENT/SOLUTIONS USED FOR EAR IRRIGATION
a. Equipment. See figure 6-2.
Asepto syringe (glass).