Acta Biomedica Scientia

ASSOCIATION BETWEEN HIGH RISK FACTORS AND INITIAL SCREENING RESULTS OF NEWBORN HEARING SCREENING

Ashvind Lakshmiah* & Mirunalini devi G.K.V.

ashvind.zulu@gmail.com

Congenital Hearing Loss, Microphone, Neonatal Intensive Care Unit, Hearing Screening

Joint Committee on Infant Hearing (JCIH, 2007) has recommended the High-Risk Register (HRR) which includes the specific risk indicators that are often associated with infant and childhood hearing loss. High false positive results in initial screening of NHS has been reported. Therefore, a second screening is always recommended before a diagnostic evaluation. The reasons attributed for high false positive results are fluid/debris in the ear canal which usually subsides within a week’s time. The refer results warrants for another visit that increases the anxiety of parents. Thus, there is a great need to analyse the factors associated with the ‘refer’ result in the initial screening. Though the risk factors are known to influence referral rates (JCIH, 2007), there is a need to measure the strength of association. The aim of this study is to do a retrospective analysis and find the association of high risk factors with the initial screening results of newborn hearing screening. The study was conducted at Department of Paediatrics, Chettinad Medical College and Research Institute, Chennai, Tamilnadu and Institutional ethics committee approval was taken. From an ongoing newborn hearing screening program in our OP, medical records of all the babies who underwent hearing screening between the month of April 2017-August 2018 were extracted and analysed in our college. All babies have been subjected to the following screening protocol. Screening was done using DP-OAE (Distortion product otoacoustic emissions) or A-ABR (Automated-Auditory Brainstem Response) after 10 days of birth but within 1 month of age. DP-OAE screening was done for all babies except for babies with hyperbilirubenemia (? 18mg/dL) and NICU stay >5 days. Babies who do not pass the initial screening, a re-screening is carried out after 2 weeks. Passing criteria is >4 dB SNR for at least 3 frequencies in both ears.Among the total number of babies screened (1653), 147 (9%) obtained ‘refer’ results in the screening. 753 (45.5%) had one or more high risk factors. Among the babies screened, 85 babies with high risk factors and 62 without risk factors got ‘refer’ results in the initial screening. Initial screening results were compared across risk factors to see the strength of association. There is a significant association between refer results and overall high-risk factors in initial hearing screening. Within the high-risk factor group, individual risk factors like craniofacial anomalies, preterm, low birth weight and NICU stay seem to be the most important risk factors influencing referrals in the initial screening. Among the combined high-risk factors, preterm and low birth weight combination was more commonly seen in babies with refer results and it has a highly significant association. Since, refer results are twice more often obtained in high risk babies, it is important to have a system in place and a logistic plan for the follow up of these babies.