|Year : 2017 | Volume
| Issue : 4 | Page : 175-180
Universal neonatal hearing screening program in private hospital, Qatar
Hanaa H Elsanadiky1, Pretty O Afifi2
1 Department of Audiology, Otorhinolaryngology, Faculty of Medicine, Tanta University, Tanta, Egypt
2 Department of Audiology, Otorhinolaryngology, Ain Shams University, Cairo, Egypt
|Date of Submission||11-Mar-2017|
|Date of Acceptance||09-Aug-2017|
|Date of Web Publication||12-Mar-2018|
Hanaa H Elsanadiky
Al-Ahli Hospital, Ahmed Bin-Ali Street, Qatar, PO Box 6401
Background Newborn hearing screening is now the accepted standard of care in several countries and is becoming increasingly more established worldwide. The early detection of hearing loss is important to avoid complications in language development.
Aim The aim of this study was to evaluate two-stage neonatal hearing screening program in a single private hospital in Doha, Qatar.
Patients and methods A total number of 10 310 babies were tested from May 2011 to May 2016. A universal two-stage hearing screening (universal neonatal hearing screening) protocol was used. Transient-evoked otoacoustic emissions (TEOAEs) were used twice for hearing screening of all babies. The first-stage screening was performed at the first 2–3 days of life before discharge from the hospital, and the second-stage screening was performed after 2 months. Auditory brainstem response (ABR) was assessed later for babies who failed TEOAEs.
Results Most of the studied neonates were delivered by means of caesarian section (55%) with a mean weight of 3.19±0.46 kg. All (100%) neonates attended the first-stage hearing screening, and only 27.8% of neonates attended the second stage. The most frequent risk factor was prematurity (54.6%). The percentage of high-risk babies was 19.1% from the total neonates for the 3 years recorded for high risk. 10.3% attended the second stage and only one-fourth underwent diagnostic ABR. A percentage of 0.001–0.003 hearing disorder was recorded.
Conclusion Two-stage neonatal hearing screening protocol should include automated ABR and not only TEOAEs.
Keywords: auditory brainstem response, Doha, Qatar, neonatal hearing screening, Transient-evoked otoacoustic emissions
|How to cite this article:|
Elsanadiky HH, Afifi PO. Universal neonatal hearing screening program in private hospital, Qatar. Tanta Med J 2017;45:175-80
| Introduction|| |
Hearing loss is one of the most frequent congenital diseases present at birth occurring in about one to three of every 1000 healthy neonates and two to four of every 100 neonates in the neonatal intensive care unit (NICU) ,. Many etiological factors may result in hearing loss in neonates. Genetic causes account for at least 50–60% of childhood hearing loss − for example, congenital anomalies and family history of childhood hearing impairment. Environmental causes of hearing loss include, for example, rubella embryopathy, prematurity, bacterial meningitis, hyperbilirubinemia, asphyxia, and head trauma .
Screening is the process of applying certain rapid and simple tests, examinations, or other procedures to generally large numbers of individuals, which will identify those persons with high probability of the disorder. Neonatal hearing screening (NHS) is now an accepted standard of care in several countries and is becoming increasingly more established worldwide .
The Joint Committee on Infant Hearing (JCIH) in 2007 endorsed the goal of universal detection of infants with hearing loss as early as possible. Screening should be completed by 1 month of age, and all infants with hearing loss should be identified by 3 months of age and receive intervention by 6 months of age .
The JCIH  and Kileny and Riper  emphasized the goal of newborn hearing screening so as to maximize linguistic competence and literacy development for children who are deaf or hard of hearing. Even American Academy of Pediatrics  published an independent endorsement of universal newborn hearing screening calling for pediatricians to take more active role. The JCHI  issues of the year 2000 Position Statement describe principles underlying effective Early Hearing Detection and Intervention program. The early identification of congenital hearing loss is necessary to minimize the consequences of hearing impairment on future communication skills .
Evoked otoacoustic emissions are extremely useful in infant hearing screening. They are accurate, economic, easy procedure, and time efficient. Many researchers had administered automated auditory brainstem response (AABR) for screening neonates to identify patients with auditory neuropathy spectrum disorder, and to reduce the number of false-positive results .
Both types of otoacoustic emissions and AABRs were used on large sample of babies and infants from ICUs; however, risk factor screening identifies only 50% of infants with significant hearing loss . Despite the presence of many reliable screening methods, universal neonatal hearing screening (UNHS) programs are still not available in many countries. Newborn hearing screening is now the accepted standard of care in several countries and is becoming increasingly more established worldwide. White and Edhi  reported eight countries screening over 90% of newborns, ten screening between 25 and 89% of births, and a further 54 implementing pilot or small-scale programs, many working to the development of national system.
In Qatar, there is a relatively high prevalence of consanguineous marriage together with lack of public awareness about the importance of hearing screening. A two-stage UNHS programs was started in 2003 and was officially declared in 2004 in all public and private hospitals.
Accordingly, this study was conducted to evaluate UNHS program using two-stage otoacoustic emission, presenting results and raising problems faced in 5-year program.
| Patients and methods|| |
This prospective study was conducted at a private hospital in Doha, Qatar, between May 2011 and May 2016. A total number of 10 310 neonates were examined. About 20% neonates were admitted in the NICU with high-risk registry for hearing loss as listed by JCIH  (high-risk group).
All neonates were subjected to the following: detailed medical, perinatal, and family history and clinical examinations with emphasis on estimation of gestational age and assessment of Apgar score at 1 and 5 min. Otological examination included external examination of auricles and otoscopic examination for patency and structure of the external auditory canal, tympanic membrane structure, and consistency. Moreover, laboratory investigations included complete blood count and serum bilirubin.
Neonatal hearing screening
NHS was performed by the audiologist by applying the national program of the country. This protocol for NHS program is as follows: infants were tested using transient-evoked otoacoustic emissions (TEOAEs), which was performed in two stages. The first stage was carried out at the first 2–3 days of life before discharge from the hospital. If the infant did not pass the test in the first stage in one or both ears, they were scheduled to repeat within 10–15 days after birth. In the second stage, TEOAEs were performed for all infants at the age of 2 months. Failures of the second stage and all high-risk group were referred for diagnostic auditory brainstem response (ABR) assessment.
Tympanometry was performed using MADSEN OTOflex 100 (Denmark), high-frequency probe tone (1 kHz).
Transient-evoked otoacoustic emissions
TEOAEs were measured using a portable Vivosonic Integrity V500 (Vivosonic, Canada). It was elicited using click stimuli at level 80 dBSPL. Probe fitting and quiet state of the infant are the most important factors for better stimulus. The amplitude of the TEOAEs was determined in four frequency bands 1, 2, 3, and 4 kHz.
The results of TEOAEs were interpreted according to the Rhode Island criteria : pass (P), response is 3 dBSPL or more in at least four frequency bands; partial pass (PP), positive response in at least two frequency bands; and refer (R), no response is present in any frequency band.
Testing was performed while infants were naturally sleeping or were alert and calm. If the test could not be performed due to active or crying infants, they were retested on another day. Moreover, retesting was performed for those who failed to pass in one or both ears before discharge from hospital. Infants who did not pass either the first or the second stage in one or both ears or of high risk were scheduled to undergo diagnostic ABR evaluation and tympanometry. The test was performed by the same observer.
Auditory brainstem response
Using Vivosonic Integrity V500, infants were naturally sleeping. Three surface electrodes were placed so that the active electrode was applied to the forehead and the reference and ground electrodes to the ipsilateral and contralateral mastoids, respectively. Acoustic rarefaction unfiltered clicks of 0.1 ms duration were presented at a rate of 21 P/s at 80 dBnHL and down in 20 dB steps until threshold and then 10 dB steps. A total of 1024 sweeps were differentially amplified. High-pass filter cutoff frequency was 30 Hz, and low-pass filter cutoff frequency was 3000 Hz within 15 ms analysis time.
Assessment of ABR pass was based on the detection of wave V at expected latency according to norms recorded by the same equipment and down to threshold (30 dBnHL). At least two recordings were obtained for each intensity. Abnormal results of ABR were interpreted as permanent congenital hearing loss with failed test of a greater than or equal to 40 dBnHL in the presence of normal middle ear function.
Results were collected, tabulated, and statistically analyzed using an IBM compatible personal computer with SPSS statistical package, version 18. Descriptive statistics including number, percent for qualitative data, and mean, SD for quantitative data were used. The criterion for statistical significance was set at P-value less than 0.05 and P-value less than 0.001 for highly statistical significance.
| Results|| |
The Newborn Hearing Screening (NBHS) program was conducted at a private hospital in Doha, Qatar, between May 2011 and May 2016 (5 years). A total number of 10 310 neonates were screened for hearing loss, 5054 female and 5256 male neonates. Their mean weight was 3.19±0.46 kg. Most of the studied neonates were delivered through caesarian section [5670 (about 55%)].
[Figure 1] represents the sex distribution from 2011 to 2016; the number of male and female neonates were increased directly proportional to increase in the total number of neonates.
There were no significant differences between them each year.
[Table 1] represents description of all neonates in each year. The number and the percentage of the neonates attending the first and second stage were also analyzed in the table. All neonates (n=10 310) were examined using TEOAEs in the first stage of hearing screening, whereas only 2929 of neonates attended the second stage, which was a very low percentage (about one-third of the total).
|Table 1 Descriptive table for neonates who attended first and second stages of neonatal hearing screening|
Click here to view
[Figure 2] shows the distribution of risk factors among all studied neonates. The highest risk factor was prematurity (54.6%), followed by sepsis (12.6%), hyperbilirubinemia (12.5%), hypoxia (2.8%), family history of hearing loss (2.4%), and congenital hearing loss (1.3%). The other 12.8% were admitted to the NICU for different causes (e.g., intrauterine growth retardation, respiratory distress syndrome, uncontrolled diabetes mellitus, and tachypnea). We were not able to record the high-risk factors for the neonates in 2011 and 2012.
|Figure 2 Distribution of risk factors for hearing impairment among high-risk neonates|
Click here to view
Therefore, failure in the NHS test following this protocol must be taken in consideration and expecting a possible hearing loss. All babies who failed to pass the TEOAEs bilaterally or unilaterally and all high-risk babies were scheduled for ABR.
[Table 2] shows the percentage of high-risk babies in each year per total number of neonates. The mean was 19.1% from the total neonates for the 3 years recorded for high risk. The high percentage was for 2013–2014 and the lowest was for 2014–2015. For neonates attending second stage, the percentage decreased to about half of those attended the first stage (10.3%); the high attendance rate was for 2015–2016, which indicates more awareness about the possibility of hearing deficit due to risk factors. All high-risk neonates were scheduled for diagnostic ABR; only one-fourth (5.3%) of them underwent the test; the highest attendance was recorded for 2015–2016.
|Table 2 Descriptive table for high-risk neonates who underwent first and second stages and auditory brainstem response|
Click here to view
[Table 3] shows the neonates who were scheduled for diagnostic ABR. All neonates who underwent the ABR test were high-risk neonates. The number of neonates who passed the test during 2013–2014 were 107/111 (about 96.4%), and the incidence of failed ABR was 0.002%. During 2015–2016 there were 93/96 (96.8%), and the incidence of failed ABR was 0.001%. The lowest percentage of neonates who passed the test was seen in 2015–2016 [145/152 (95.4%)]. The percentage of children who failed ABR ranged from 0.001 to 0.003. Analysis for all risk factors revealed that all factors were not significantly associated with ABR results (P>0.5).
|Table 3 Descriptive table for neonates attend auditory brainstem response and percentage of hearing loss|
Click here to view
| Discussion|| |
The prevalence of hearing loss is 20 times more in neonates compared with other disorders that are routinely screened. Until just a decade ago, there was a late diagnosis of hearing loss with average age at identification of congenital hearing loss reported as 2.5–3 years or even later . Early intervention in the first 6 months of life is particularly important for speech and language development; accordingly, parents and professionals prefer early diagnosis ,.
It was found that results of hearing screening was better when recorded on the third day of delivery or before discharge of the mother from the hospital. This is in agreement with Clarke et al. , who suggested that screening for hearing loss in neonates should be performed 4 days after birth. Our strategy of UNHS is to screen all newborns shortly after birth, not just those with risk indicators. The goal is to avoid delaying the diagnosis of hearing loss in an infant who may not have any known or recognized risk indicators, and who would be included in a high-risk screening program. This strategy is in agreement with JCHI . Some authors suggested that as many as 50% of newborns with hearing loss were being missed if only high-risk screening was carried out . With the advent of NHS it was thought that it may no longer be necessary to identify risk indicators. However, risk indicators continue to represent a critical component in the understanding of the pathophysiology of congenital hearing loss.
A two-stage TEOAEs was performed in order to reduce the false positives; this protocol is in agreement with other studies ,. Therefore, failure in the NHS test following this protocol must be taken in consideration and expecting a possible hearing loss. All babies who failed to pass the TEOAEs bilaterally or unilaterally and all high-risk babies were scheduled for ABR. In the current study, the protocol depended on TEOAEs, which was consistent with Trinidad et al. , who reported that TEOAEs is an effective method when used in infantile auditory screening, as it is objective, bloodless, and quick. Its correlation with auditory-evoked potential is very high, which proves their reliability. We believe that universal screening is necessary, although a much higher incidence of deafness is encountered among children with risk factors. The establishment of programs for the precious detection of infantile deafness should not be delayed.
In this study, TEOAEs test revealed failed response in some neonates, including high risk. Korres et al. , who examined hearing in well-nursery babies with TEOAEs in Greece, found a failure rate of 2.3%, which is near our findings. The results of TEOAES screening varied widely in the literature according to the characteristics of the screened population. However, El-Gamal et al. , in Egypt, reported a failure rate of 54% in multiple risk factor neonates and 20% in the single risk factor neonates. However, Abdullah et al.  found that 11.8% of the screened high-risk neonates in Malaysia failed TEOAEs test. Imam et al.  recorded failed response in 28%.
This study did not follow two-stage protocol of Vignesh et al. . They used two-stage protocol AABR along with Distortion Product Otoacoustic Emissions (DPOAEs), at the initial level of testing; it significantly reduced referral rates in newborn screening programs. Moreover, AABR decreased the false-positive responses, hence increasing the efficiency of screening program. Suppiej et al.  reported that the brainstem auditory-evoked potentials appeared to be the more reliable test for hearing screening of high-risk neonates because of highest sensitivity and specificity and should be used to confirm the diagnosis of ‘auditory neuropathy’ in high-risk neonates.
In our study, many babies did not attend the second-stage TEOAEs and ABR. Hence, it affects the final results for hearing impairment. The results of this study emphasized that one to three infants per 1000 have congenital hearing loss ([Table 3]). These results are in agreement with the results of University of Michigan, in which hearing loss in infancy is one of the most common congenital defects, affecting two to three per 1000 infants. It is well-documented that children who are identified through universal newborn hearing screening and diagnosed at an early age have better language outcomes at school age than those who are identified later in life. The prevalence of newborn and infant hearing loss has been estimated in other studies from 1.5 to 6.0 per 1000 live births ,,.
Risk factor screening identifies only 50% of infants with significant hearing loss ,,. Those findings suggest that, among the sensorineural hearing loss of unknown etiology, those of a hereditary origin should be considered. With the progress in the field of molecular genetics, new genes could be responsible for sensorineural hearing loss. The development and implementation of newborn hearing screening has been driven by the aim of reducing the negative impact of congenital hearing loss on children’s health and development, which in turn leads to social and educational underachievement and limits life chances.
Finally, the potential limitations inherent in this study include lack of a standard method to track infants who failed screening tests and missed diagnostic ABR. However, we believed that our findings provide new insights into NHS in Qatar.
In conclusion, TEOAEs is sensitive, rapid, and simple test in newborn hearing screening. Universal two-stage NHS protocol should include AABR for all babies, not only the high-risk group. It is the key components of what constitutes ‘early intervention’, and in particular what marks that intervention as being of high quality and leading to improved outcomes.
Financial support and sponsorship
Conflicts of interest
There was no conflicts of interest.
| References|| |
Erenberg A, Lemons J, Sia C, Tunkel D, Ziring P. Newborn and infant hearing loss: detection and intervention. Pediatrics 1999; 103:527–530.
Nelson H, Bougatsos C, Nygren P. Universal newborn hearing screening: systematic review to update the 2001 US preventive services task force recommendation. Pediatrics 2008; 122:e266–e 276.
Morton C, Nance W. Newborn hearing screening − a silent revolution. N Engl J Med 2006; 354:2151–2164.
Carr G. Screening: evaluating the outcomes of early intervention. 2015; 23:68–69.
American Academy of Pediatrics, Joint Committee on Infant Hearing. Year 2007 position statement: principles and guidelines for early hearing detection and intervention programs. Pediatrics 2007 120:898–921.
Kileny P, Riper L. Newborn hearing screening: lessons learned. ENT Audiol News 2013; 22.
American Academy of Pediatrics. New-born and infant hearing loss: detection and intervention task force on newborn and infant hearing. Pediatrics 1999; 103:527–530.
Joint Committee on Infant Hearing. Year 2000 position statement: principles and guidelines for early hearing detection and intervention program. Audiol Today 2000; 12:7–27.
Flucher A, Purcell AA, Baker E, Munro N. Listen up children with early identification hearing loss achieve age-appropriate speech/language outcomes by 3 years-of-age. Int J Pediatr Otorhinolaryngol 2012; 76:1785–1794.
Korres S, Nikolopoulos P, Komkotou V. Newborn Hearing Screening: effectiveness, importance of high risk factors, and characteristics of infants in the neonatal intensive care unit and well-baby nursery. Otol Neurotol 2005; 26:1186–1190.
Mauk G, White K, Mortensen L, Behrens T. The effectiveness of screening programs on high-risk characteristics in early identification of impairment. Ear Hear 1991; 12:312–319.
White K, Edhi I. The global status of newborn hearing. Paper presented at the 3rd Annual Meeting of the coalition hearing health. Pretoria, South Africa, 2012.
Maxon A, White K, Vohr B, Behrens T. Using transient evoked otoacoustic emissions for neonatal hearing screening. Br J Audiol 1993; 27:149–153.
Clarke P, Iqbal M, Mitchell S. A comparison of transient evoked otoacoustic emissions and automated auditory brainstem responses for pre-discharge neonatal hearing screening. Int J Audiol 2003; 42:443–447.
Norton S, Gorga M, Widen J. Identification of neonatal hearing impairment: transient evoked otoacoustic emissions during perinatal period. Ear Hear. 2000; 21:425–442.
Trinidad Ra, Pando P, Vega C, Serrano B, Trinida Ru, Balsco H. Early detection of hearing loss in neonates by using transient evoked otoacoustic emissions. An Esp Pediatr 1999; 50:166–171.
El-Gamal A, Hazaa N, Awwad K. Otoacoustic emissions in high risk neonates. Egypt J Otolaryngol 2001; 185:145–155.
Abdullah A, Hazim M, Amyzan A. Newborn hearing screening: experience in a Malaysian hospital. Singapore Med J 2006; 47:60–64.
Imam S, El-Farrash R, Taha H, Bishoy H. Targeted versus universal neonatal hearing screening in a single Egyptian center. ISRN Pediatrics 2013; 2013:574937.
Vignesh S, Jaya V, Sarathy K, Vanthana M. Prevalence and referral rates in neonatal hearing screening program using two step hearing screening protocol in Chennai: a prospective study. Int J Pediatr Otorhinolaryngol 2015; 79:1745–1747.
Suppiej A, Rizzardi E, Zanrdo V, Franzoi M, Ermani M, Orzan E. Reliability of hearing screening in high-risk neonates: comparative study of otoacoustic emission, automated and conventional auditory brainstem. Clin Neurophysiol 2007; 118:869–876.
Watkin P. National acoustic emission screening and the identification of deafness. Arch Dis Child 1996; 47:F16–F25.
White K, Behrens T. The Rhode Island hearing assessment: implications for universal newborn hearing screening. Semin Hear 1993; 14:1–122.
Northern J, Hayes D. Universal screening for infant hearing impairment: necessary, beneficial and justifiable. Audiol Today 1994; 6:10–13.
Pappas D. Hearing impairments and vestibular abnormalities among children with subclinical cytomegalovirus. Ann Otol Rhinol Laryngol 1983; 92:552–557.
Elssmann S, Matkin N, Sabo M. Early identification of congenital sensorineural hearing impairment. Hear J 1987; 40:13–17.
[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3]