RISK FACTOR ASSOCIATED WITH HEARING IMPAIRMENT IN NEONATES

Abstract

Beginning January, 1983, a comprehensive hearing screening program for all infants less than 28 days of age was initiated. 487 infants at risk for hearing impairment were screened using a list of 20 risk criteria. Infants are classified as high risk when they meet one or more of the risk criteria. Testing involves Behavorial Observation Audiometry (BOA), Tympanography (Tymp) and Auditory Brainstem Response (ABR). Hearing impairment was diagnosed when the infant failed BOA, or ABR on two occasions. Any infant who failed Tymp received otologic exam to rule out middle ear disease. To date 440 infants were classified at high risk and 214 have been tested. 8 (3.8%) have been diagnosed as hearing impaired. The most frequent risk factors to appear in the 8 hearing impaired infants were a birthweight <1500gm (6/8), evidence of intracranial hemorrhage (7/8), and aminoglycoside exposure ≥7 days (5/8). No infant who passed hearing screening has been subsequently diagnosed as hearing impaired during developmental follow-up. This data suggests that a comprehensive aeonatal hearing screening program can identify hearing impaired infants in the neonatal period. Although many other factors have been considered as high risk, birthweight <1500gm, presence of intracranial hemorrhage and aminoglycoside exposure seem to be the most important risk factors.