Download Newborn hearing screening in Western Australia

Newborn hearing screening in Western Australia
Bailey, HD1, Krishnaswamy J2, Coates H2, French N2, Bower C1
1
TVW Telethon Institute for Child Health Research, Perth Western Australia
PO Box 855 West Perth 6872
[email protected]
2
King Edward Memorial Hospital for Women and Princess Margaret Hospital for Children, Perth
Western Australia.
The aim of the Western Australian Newborn Hearing Screening Programme is early detection
of bilateral hearing loss in order to offer and commence intervention by the time the baby is six months
of age. Universal hearing screening has been introduced in parts of the USA and Europe. Speech
and language outcomes of children with bilateral hearing loss who have commenced intervention by
six months are better than those children with bilateral hearing loss who commenced intervention
later. In 1997 in Western Australia, the median age for the fitting of hearing aids was 25 months.
Estimates of the prevalence of congenital bilateral hearing loss range from 1.4- 3 per 1000 live births.
Since February 2000 newborn hearing screening has been offered to all babies born at King Edward
Memorial Hospital for Women. During 2000, hearing screening has also been introduced to four more
large maternity hospitals in Perth. About 47% of all of the births in Western Australia and 60% of
metropolitan births occur at these hospitals.
Method: All screening is done by specially trained screeners. The screeners obtain a complete list of
the previous day(s) deliveries and every live birth is allocated a unique identification number based on
the hospital and year of birth. Written parental consent is obtained prior to screening. Where
possible, well babies are screened when at least 24 hours of age. The initial screen is done using an
ECHOCHECK (ILO OAE screener) which measures transient evoked otoacoustic emissions (TEOAE).
If a pass response is not obtained in both ears, an automated auditory brainstem response
measurement (AABR) is done prior to discharge using either the SABre (SLE Ltd.) system or Algo 2e
(Natus). Babies who are admitted to a special care nursery are screened when at least 34 weeks
gestation and fit enough for the screen. For a small number of high risk babies, AABR technology,
rather than TEOAE is used for the initial screen. The results of the screening and basic demographic
data are entered onto a specially designed database developed in FileMaker Pro. All babies who do
not pass in both ears are given appointments for repeat screening in 2-3 weeks. Any baby who does
not pass the follow-up screening in both ears is referred for urgent assessment by a paediatric
audiologist while any baby who passes in only one ear is referred for assessment at seven months of
age.
Results: About 5000 babies were eligible for screening in the first eight months of the programme.
Ninety-five percent of babies received hearing screening. Reasons for not being screened included
discharged prior to screening, transfer to another hospital and parental refusal. Eighty percent of
babies were screened using only TEOAE. In the first five months of screening, 94% of screened
babies passed hearing screening in both ears. This increased to 98% in the next three months. A
small group of babies who required follow-up were lost due to missing multiple appointments or
parental refusal. Of those who received follow-up, 96% passed the follow-up screen. A total of ten
babies have been referred for diagnostic assessment for either a unilateral (eight babies) or bilateral
(two babies) fail. Of the latter, one was confirmed as having bilateral profound hearing loss and the
other is awaiting surgical intervention for a conductive hearing loss.
Conclusions: Hearing screening has been successfully introduced at five hospitals in the Perth
metropolitan area. Challenges in the future include reducing the proportion of babies who miss
screening and continuing to increase the proportion of babies who pass the initial screen. Over the
next few months, all aspects of the programme will be evaluated and the cost of screening per baby
calculated. This will provide information on which to base the proposed expansion to other maternity
hospitals in Western Australia.