Newborn hearing screening at the Neonatal Intensive Care Unit and Auditory Brainstem Maturation in preterm infants

https://doi.org/10.1016/j.ijporl.2019.05.004Get rights and content

Abstract

Objectives

Aim of this study is to report and discuss the results of 4 years of Newborn hearing screening (NHS) program at the Neonatal Intensive Care Unit (NICU), particularly evaluating the clinical ABR results.

Methods

Retrospective study. NHS data from NICU newborns, admitted for ≥5 days, in the period from January 1st, 2013 and December 31st, 2016, were retrieved and analyzed. NHS results were classified as following: (i) “pass” when both ears for both the a-TEOAE (automated Transient-Evoked Otoacoustic Emissions) and the a-ABR (automated Auditory Brainstem Response) protocol resulted as “pass”; (ii) “fail” when one ear, at either one of the two performed tests resulted as “fail”; (iii) “missing” when the newborns were not tested with both protocols. All “fail” and “missing” newborns were retested (with both tests): in the case of a second “fail” result, a clinical ABR was performed within a period of 3 months.

Results

A total of 1191 newborns were screened. From those, 1044/1191 resulted as “pass”, 108/1191 as “fail”, and 39/1191 as “missing”. During the re-testing of these 147 newborns, 43 were assigned as “missing”, 63 were assigned as “pass” (showing bilaterally a wave V identifiable within 30 dB nHL) and 25 failed the retest and/or did not present an identifiable wave V within 30 dB nHL. Among the 147 retested infants, we identified a group of 16 subjects who resulted as NHS “refer” and who, during the audiological follow-up, showed either: (i) a unilateral or bilateral wave V identifiable over 30 dB nHL, at the first clinical ABR assessment; or (ii) a bilateral wave V identifiable within 30 dB nHL, in a following clinical ABR test during the first year of life. These 16 subjects were defined to have an ‘Auditory Brainstem Maturation’ issue.

Conclusions

A possible “maturation” of the ABR response (and therefore of the auditory pathway) has been hypothesised in 16 out of 1191 infants (1.3%). A delay of the auditory pathway maturation in preterm babies compared to term newborns has already been suggested in the literature. A possible delay of the NHS retest could be considered, in selected cases, with significant savings in economic resources and parental anxiety.

Section snippets

Background

The incidence of congenital hearing loss rate in full-term birth is reported to be about 0.1–0.3% [[1], [2], [3]]. This rate is reported to increase up to 2–3% in newborns at the Neonatal Intensive Care Unit (NICU) [[3], [4], [5], [6], [7]].

The Universal Newborn Hearing Screening (UNHS) is mandatory for the early identification, diagnosis and treatment/rehabilitation of children with moderate to profound hearing loss [8]. The screening technology consists in the evaluation of automated

Subjects and methods

Retrospective study. NHS data from NICU newborns, admitted for ≥5 days, in the period from January 1st, 2013 and December 31st, 2016, were retrieved and analyzed. The collected data included information on: the gestational age at birth, the birth weight, the causes of admission at the NICU, the age at the time of NHS, the NHS data and the rescreening and clinical ABR testing data.

NHS was performed at the NICU, 1–2 days before discharge, by the same audiometrist when newborns were asleep. Both

Results

The study sample consisted of 1191 newborns screened at the NICU. The descriptive characteristics of the sample are presented in Table 1. In terms of subjects, 261 were tested in 2013, 258 in 2014, 318 in 2015 and 354 in 2016, respectively. The mean age at NHS was 11.5 ± 15.3 days, while the mean ‘screening age’ at NHS was 37.8 ± 2.7 weeks.

Table 2 presents the causes of hospitalization at the NICU. The most common cause is represented by prematurity 46.8% (557/1191 infants had a gestational

Discussion

To date, several NHS protocols (using a-TEOAE, a-ABR and ABR) for well-babies have been proposed [[20], [21], [22], [23], [24]], while, according to the JCIH protocols [1], hearing screening for NICU infants should be performed by both aOAE and aABR.

It is well known that NHS cannot detect some forms of hearing loss, in particular those with a delayed onset, nor mild or isolated frequency losses [1]. Also, NHS does not provide a definition of hearing loss in terms of severity. When indicated, in

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Declarations of interest

None.

Acknowledgments

Authors wish to thank Monica Rosignoli for her precious help with the statistical analysis.

References (32)

  • Z.D. Jiang et al.

    Normal brainstem responses in moderately preterm infants

    Acta Paediatr.

    (2008)
  • A.M. Korver et al.

    DECIBEL-collaborative study group, Causes of permanent childhood hearing impairment

    Laryngoscope

    (2011)
  • P. Ghirri et al.

    Universal neonatal audiological screening: experience of the University Hospital of Pisa

    Ital. J. Pediatr.

    (2011)
  • H.M. Fortnum et al.

    Prevalence of permanent childhood hearing impairment in the United Kingdom and implications for universal neonatal hearing screening: questionnaire based ascertainment study

    BMJ

    (2001)
  • S. Berrettini et al.

    Newborn hearing screening protocol in tuscany region

    Ital. J. Pediatr.

    (2017)
  • J.L. Johnson et al.

    A multicenter evaluation of how many infants with permanent hearing loss pass a two-stage otoacoustic emissions/automated auditory brainstem response newborn hearing screening protocol

    Pediatrics

    (2005)
    • View full text
    © 2019 Elsevier B.V. All rights reserved.