1. External Ear
    • 1. External Auditory Canal - opening of external ear
    • 2. Tympanic Membrane (ear drum) - separates the external and middle ear. Translucent membrane with a pearly gray color
  2. Middle Ear
    • tiny air filled cavity inside the temporal bone
    • 1. Malleus - tiny ear bones or auditory ossicles
    • 2. Incus - tiny ear bones or auditory ossicles
    • 3. Stapes - tiny ear bones or auditory ossicles, opens to TM
    • 4. Eustachian Tube - connects middle ear with the nasopharynx and allows passage of air. The tube is normally closed, but it opens with swallowing or yawning
  3. Middle Ear Function
    • a. Conducts sound vibrations from the outer ear to the central hearing apparatus in the inner ear
    • b. Protects the inner ear by reducing the amplitude of loud sounds
    • c. Eustachian Tube - allows equalization of air pressure on each side of the TM so that the membrane does not rupture
  4. Inner Ear
    • 1. Bony Labyrinth - holds sensory organs for equilibrium and hearing
    • a. Vestibule - compose the vestibular apparatus
    • b. Semicircular Canals - compose the vestibular apparatus
    • 2. Cochlea - contains the central hearing apparatus
  5. Hearing
    • A. Peripheral - ear transmits sound and converts its vibrations into electrical impulses which can be analyzed by the brain
    • B. Brain Stem - binaural interaction, permits locating the direction of a sound in space as well as identifying the sound
    • C. Cerebral Cortex - Interpret the meaning of the sound and begin the appropriate response
    • D. Pathway of Hearing - normal pathway of hearing is air conduction; alternate route of hearing is by bone conduction (bones of the skull vibrate - vibrations are transmitted directly to inner ear and to cranial nerve VIII)
    • E. Hearing Loss - Anything that obstructs the transmission of sound impairs hearing
    • 1. Conductive Hearing Loss - involves a mechanical dysfunction of the external or middle ear
    • 2. Sensorineural (or Perceptive) Hearing Loss - pathology of inner ear, cranial nerve VIII or the auditory areas of the cerebral cortex
  6. Equilibrium
    • labyrinth (inner ear) constantly feeds information to your brain about your body’s position in space
    • A. Vertigo - strong, spinning, whirling sensation
  7. Transcultural Considerations
    • A. Otitis Media - increased incidence and severity in Native American, Alaskan, Canadians and Hispanics. Otitis media also increased incidence in premature
    • infants, Down Syndrome and bottle fed infants.
    • B. Cerumen - Asians and Native Americans usually have a dry flaky cerumen; Caucasian and African Americans/Blacks usually have wet/moist cerumen
  8. History (Subjective)
    • A. Ear aches, ear pain, hx of ear infections - adult, childhood, frequency, tx.
    • B. Ear d/c or difficulty hearing.
    • C. Any trouble/difficulty hearing
    • D. Loud noise exposures, environmental noise - home or work exposures
    • E. Hx Tinnitus
    • F. Hx Vertigo
    • G. Self Care - how are ears cleaned, last time hearing evaluated
  9. Physical Exam/Assessment of Ears (Objective)
    • A. Inspect and palpate the size and shape of the external ear
    • B. Observe for tenderness with external palpation
    • C. Otoscopic Examination
    • 1. External Canal - note any redness, swelling, lesions foreign bodies or d/c
    • 2. Tympanic Membrane - color & characteristic, LR, landmarks, position
    • D. Hearing Acuity - audiometry or crude test with conversation
    • E. Voice Test - whisper 2 syllable word at 2 feet distance - cover lips/mouth
    • F. Tuning Fork Test -
    • 1. Weber - vibrating tuning fork in the middle of the persons skull and ask if the tone sounds the same in both ears or better in one
    • 2. Rinne Test - compares air conduction and bone conduction sound (place the stem of the vibrating tuning fork on the mastoid process and ask them
    • when the sound goes away. Quickly invert fork so vibrating end is near the ear canal. Normal - sound is heard 2X as long by air conduction as by bone conduction AC>BC
  10. Ear Abnormalities
    • A. Otitis Externa
    • B. Otitis Media
    • C. Serous Otitis Media
    • D. Sebaceous Cyst
    • E. Perforation
    • F. Darwin’s Tubercle
    • G. Tophi
    • H. Cerumenosis
    • I. Foreign Body
Card Set
Nursing 307