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Using an ear thermometer


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In Brief

HIGHLY VASCULAR, the ear is well suited for indirect measurement of core body temperature. The tympanic membrane (eardrum) lies close to the external carotid artery, so infrared temperature readings taken there reliably indicate core body temperature.

  • Explain the procedure and ask your patient to keep his head still. If the patient is a young child, have someone else hold his head still.
  • If your patient wears a hearing aid, take his temperature in the other ear or remove the hearing aid and wait 20 minutes to use that ear.
  • Place a new, clean lens filter on the thermometer probe and turn on the power.
  • If you're right-handed, measure temperature in the patient's right ear; if you're left-handed, use the left.
  • Figure
    Perform an ear tug to straighten the ear canal: In a child, pull the ear straight back; in an adult, pull it slightly upward and backward.
    Still tugging, use a slight rotating motion to insert the probe gently and slowly, aiming it toward the tympanic membrane. To prevent air temperature from affecting the reading, make sure the probe penetrates at least one-third of the external ear canal and forms a complete seal.
  • Follow the manufacturer's directions for operating the thermometer. After taking the reading, gently remove the probe from the ear canal, discard the disposable lens cover, and place the thermometer in the charger to prepare it for later use. Document the temperature reading.
  • Try to use the same ear each time you take your patient's temperature because readings may differ from the left ear to the right. However, wait 2 minutes if you need to recheck it in the same ear.
  • Make sure the biomedical staff calibrates and maintains the thermometer according to the manufacturer's guidelines.
  • Don't forcefully insert the thermometer probe into the ear canal.
  • Don't use an ear thermometer if the ear canal is completely occluded by earwax (which could affect accuracy) or if the patient has otitis externa (which would cause pain).


Berman, A., et al. (eds): Kozier & Erb's Techniques in Clinical Nursing. Upper Saddle River, N.J., Pearson Education, Inc., 2002.
    Nicoll, L.: “Heat in Motion: Evaluating and Managing Temperature,” Nursing2002. 32(5, Suppl.):1–10, May 2002.
      © 2003 Lippincott Williams & Wilkins, Inc.