Recommended Hearing Screening Equipment
Only FDA approved equipment is recommended for use with infants and children. This equipment may be either:
1. Distortion Product (DPOAE) or Transient Otoacoustic Emissions (TEOAE) which is capable of screening at several frequencies from 1000 Hz to 6000 Hz
2. Automated Auditory Brainstem Evoked Response (AABR) equipment that detects mild to profound hearing loss in infants and newborns.
3. Noisemakers or other non-calibrated signals are not appropriate.
The equipment should be calibrated in accordance with the manufacturer's recommendations annually. There are no national standards for the calibration of OAE or AABR instrumentation. In the absence of national standards, it is recommended to also obtain biological normative data for the instruments and protocols being used.
It is recommended that a log should be kept documenting the dates of calibration and repair or replacement of parts.
APPROPRIATE EQUIPMENT USAGE:
OAE screening equipment can be used to successfully test a cooperative, quiet child of any age.
AABR screening test requires the child be asleep during the test procedure. Any muscle movement artifact of the face or eyes can invalidate the test results as they can mimic a brainstem response. AABR therefore is usually only useful for infants and children under 6 months of age who can be tested under natural sleep.
Sedating a child to complete a hearing screening is not appropriate or within normal standard of care. Sedation should only be used to complete a diagnostic electrophysiological test battery (air, bone, and toneburst ABR) by the audiologist and then only should be performed as the last resort. The sedation and testing should take place only in an environment appropriately set up for pediatric emergency resuscitation and under the constant supervision of a qualified physician. Audiologists are not qualified to administer or monitor sedation.
Behavioral audiometry should always be attempted before sedated testing. This can include both Visual Reinforced Audiometry and Conditioned Play Audiometry combined with impedance measures. A child with normal hearing can usually be identified by a skilled audiologist without electrophysiological testing.
A child under the age of 3 years, however; must have at least one diagnostic ABR to confirm a diagnosis of hearing loss before a hearing aid or cochlear implant can be fitted. Screening ABR results are not specific or comprehensive enough for a diagnosis of permanent hearing loss.