Assessment of Hearing Loss by OAE in Asphyxiated Newborns

BACKGROUND: Severe birth asphyxia (apgar < 7 at the 5th minute of birth) is recognized as a hearing loss risk factor by the joint committee on infant hearing (JCIH). About half of the newborns with hearing loss do not indicate any sign and risk factor at birth. Accordingly, the joint committee recommended performance of hearing screening test in 2000, especially for babies born with risk factors. OBJECTIVES: The aim of this study was to evaluate hearing loss in asphyxiated neonates. Early diagnosis would result in early treatment of these newborns. PATIENTS AND METHODS: We assessed the relationship between asphyxia and hearing impairment in newborns admitted to a referral hospital, Tehran, Iran within 3 years (2003 - 2006). Hearing problems were diagnosed and followed by otoacoustic emission (OAE) in the third and fifth days of birth. Asphyxiated neonates with abnormal OAE were referred to an ENT specialist; second OAE and tympanometry were carried out after 2 weeks. Based on the results, newborns underwent treatment or were discharged. RESULTS: Of 149 asphyxiated neonates, 80 had mean first minute apgar score of 4.01, and mean 5th minute score was 7.24. Two percent (3/149) of asphyxiated neonates had abnormal OAEs. No statistical correlation was found between the 5th minute apgar score and abnormal OAE (P value = 0.391). However, a significant relationship between the mean birth weight and abnormal OAE (P value = 0.0406) was found. CONCLUSIONS: It seems that birth asphyxia is not correlated with hearing loss.