Auditory Screening inHigh-risk Infants

Overview

The present report concerns hearing screening in 700 high-risk (pre-term) infantsusing transient evoked otoacoustic emissions (TEOAE) and brain stem auditory evoked potentials(BAEP). The findings of 7 years’ study evaluate screening of low birth weight neonates at increasedrisk of hearing impairment. A total of 700 infants (347 girls and 353 boys) were tested: 406 infantswith very low birth weight (VLBW) under 1500 g, 163 infants had extremely low birth weight - under1000 g. From the presented results in this sample of 700 high-risk infants 18 (2.6%) were identifiedto have a sensorineural hearing loss: 11 infants had bilateral severe to profound losses, and 2 hadunilateral losses, and 5 had medium forms of hearing impairment. Although the etiology of hearingloss in these 18 infants cannot be specifically elucidated, RDS (respiratory distress syndrome) andits treatment appear to place an infant at risk for hearing loss. Other frequent clinical complicationsinclude abnormal CNS (central nervous system) findings - intracranial haemorrhage into theventricles or in the area around the ventricles. Premature and low birth weight infants are at riskfor intracranial bleeding because of complex anatomical and physiologic processes occurring in thisstage of fetal development. Any primary disorder that results in hypoxia may affect an infant’shearing and neurologic status. A group of 497 neonates treated with gentamicin sulphate andampicilin usually had an underlying disease or severe infection, including RDS, hypoxia and sepsis,all of which were clinically significant indicators of high risk for auditory pathway dysfunction.The 2.6% incidence of hearing loss in high-risk infants is accepted by the authors as favourable. Theresults of 7 year’s study confirm a very good standard of initial care of newborns in NICU (neonatalintensive care unite).

Key words:
low birth weight neonates (LBW), hearing loss, TEOAE, BAEP.