Assessment of Hearing Impairment in NICU Graduates by Otoacoustic Emission and Brainstem Evoked Response Audiometry Tests

Abstract

Objectives: To find out the incidence of hearing impairment in Neonatal Intensive Care Unit (NICU)-admitted newborns and to correlate between several risk factors. Design: Prospective observational study. Setting: In a tertiary teaching hospital of Odisha between October 2014 and October 2016. Study population: 100 newborns delivered in the institution and admitted in NICU with usual indications and risk factors that underwent otoacoustic emission 1 and 2 (OAE1, OAE2) and Brainstem Evoked Response Audiometry (BERA). Results: 84 babies in OAE1 and 86 babies in OAE2 got “pass” results. In BERA test, 92 babies got normal waveform. 7 (13.7%) of 51 premature babies, 5 (38.5%) of 13 very low birth weight babies, 7 (17.5%) of 40 babies receiving ototoxic medication for >5 days, 7 (31.8%) of 22 babies with hyperbilirubinemia, 6 (42.9%) of 14 babies with sepsis, 5 (20%) of 20 babies with birth asphyxia, 3 (60%) of 5 babies under mechanical ventilation for >5 days, 1 baby with ear abnormality, and 1 (50%) out of 2 babies with congenital infections had hearing impairment and statistically significant association with abnormal OAE and BERA test. Conclusion: There is high incidence of hearing loss in NICU-admitted newborns. OAE and BERA both should be performed for complete evaluation of hearing. Important risk factors are elaborated. Predischarge hearing assessment in NICU is most important.