Hearing loss in high risk neonates

Abstract

Objective: To determine the incidence and risk factors associated with hearing loss in high risk neonates. Design: Descriptive cross sectional study. Setting: Level II NICU of a tertiary care hospital. Participants: 280 high risk infants were screened. Intervention: All high-risk babies were initially screened with both transient evoked otoacoustic emissions (TOAE) and Auditory brainstem response (ABR). Outcome variables: Primary: to determine the incidence of auditory neuropathy in high risk infants; Secondary: risk factors in those babies identified with hearing loss. Results: Incidence of hearing loss was 17.8 per 1000 screened (95% C.I is 0.24% - 3.32%), with bilateral hearing loss seen in 14.2 per 1000 babies. Highest incidence of hearing loss was seen is in infants with intracranial haemorrhage and meningitis (50%) followed by in decreasing orders craniofacial anomalies (20%), intrauterine congenital infections (11.11%), culture positive sepsis including meningitis (8.88%), birth weight less than 1.5 kg (7.14%), preterm < 33 weeks (4.34%), severe birth asphyxia (4%), use of ototoxic medications for more than 5 days (3.03%). The risk of hearing loss is higher with higher number of risk factors. With a single risk factor being present, it is only 0.66%, whereas with five risk factors, the incidence was 33.3%. Conclusion: There is a high incidence of hearing loss in at-risk infants. Hearing loss is commoner when risk factors such as intracranial haemorrhage or meningitis are present and with presence of multiple risk factors. This would justify the need to routinely screen all high risk infants, so that rehabilitative measures can be initiated at the earliest.