Publication:

Incidence of hearing loss in high-risk neonates admitted in neonatal intensive care unit in a tertiary care centre using otoacoustic emissions

Background Neonates admitted in neonatal intensive care units (NICU) are at higher risk of hearing impairment due to multiple perinatal and postnatal risk factors. Early detection of hearing loss is essential for timely intervention and prevention of speech and language delay. This study was conducted to estimate the incidence of hearing loss in high-risk neonates admitted in NICU in a tertiary care hospital and to identify the associated risk factors.

Methods A hospital-based observational study was conducted among neonates admitted in the NICU of SAT Hospital, Thiruvananthapuram. A total of 384 neonates with risk factors as defined by the Joint Committee on Infant Hearing were included. Hearing screening was performed using otoacoustic emission (OAE). Neonates who failed OAE screening underwent confirmatory testing using brainstem evoked response audiometry (BERA). Data regarding antenatal history, perinatal events, clinical risk factors and NICU course were collected and analysed.

Results A total of 384 neonates were screened. Thirty-two neonates failed OAE screening, of which 11 had unilateral failure and 21 had bilateral failure. Among these neonates, BERA was normal in 15 and abnormal in 17 cases. The incidence of hearing loss among high-risk neonates was 4.4%. Significant associations with hearing loss were observed with low APGAR score, presence of external anomalies, exposure to ototoxic drugs, culture positive sepsis, hypoxic ischemic encephalopathy, meningitis, intraventricular haemorrhage, respiratory distress syndrome, mechanical ventilation, recurrent apnoea and longer duration of NICU stay.

Conclusions The incidence of hearing loss among high-risk neonates admitted in NICU is considerably higher compared to the general newborn population. Early screening using OAE followed by confirmatory BERA can facilitate early diagnosis and timely intervention.