Newborn News

14 - Newborn Hearing Screening with Drs. Angela Shoup and Kris Owen

Episode Summary

We discuss the universal newborn hearing screening program, causes of hearing loss, and management of infants who do not pass their hearing screen. We are joined by Angela Shoup, PhD, and Kris Owen, AuD, Audiologists at the University of Texas Southwestern Medical Center.

Episode Transcription

Dr. Neeta Goli:

Welcome to Newborn News, a podcast where we discuss educational topics for medical professionals who care for newborns. I'm your host, Dr. Neeta Goli, a pediatrician in the UT Southwestern newborn nursery. Welcome back to the podcast. In today's episode, we'll be discussing newborn hearing screening. We are recording remotely due to the ongoing COVID pandemic. We are joined today by audiologists Dr. Angela Shoup, who is the chief of the division of communicative disorders at UT Southwestern and president-elect of the American Academy of Audiology, and Dr. Kris Owen, who is the audiology coordinator for the Parkland Universal Newborn Hearing Screening Program, and a member of the UT Southwestern audiology pediatric team at Children's.

Dr. Angela Shoup:

This Angela Shoup.

Dr. Neeta Goli:

Hi Dr. Shoup, this is Neeta, and Dr. Owen is there as well?

Dr. Kris Owen:

Hello.

Dr. Angela Shoup:

Yeah, just call me Angela.

Dr. Neeta Goli:

Okay. Thank you Angela and Kris for joining us today.

Dr. Kris Owen:

Thank you. Thanks for having us. I'm so excited to be here, and indeed, to talk with you.

Dr. Neeta Goli:

Yes, I'm excited too. Just so if you're ready, I can go ahead and jump into that. Newborn hearing loss is estimated to occur in about 1.7 in every 1,000 babies born in the US. Without routine screening, sometimes this might only be caught later in life once babies have speech delay and language delays, which can then impact cognitive development. With the advent of universal newborn hearing screening, we can now screen for this in the newborn period, so that if an infant does have hearing loss, we can intervene early to minimize the impact on the infant's development. Could you tell us some more about the causes of hearing loss and the importance of early identification?

Dr. Angela Shoup:

Sure. Although there are a variety of potential causes of congenital hearing difficulties, in many cases, the cause remains unknown. And that's sometimes difficult for families to accept. However, estimates suggests that approximately 40% is due to environmental factors with the most common of these being congenital cytomegalovirus. Congenital cytomegalovirus is estimated to cause about 15% to 25% of congenital hearing difficulties, and then the remaining 60% are believed to be due to genetic factors. Approximately one third of these are going to be associated with the syndrome and two thirds will be non-syndromic.

Dr. Angela Shoup:

When we look at early intervention and identification of hearing loss, it's important for us to intervene early as a lack of sensory input to the developing auditory system can lead to sensory deprivation, degenerative effects that impact the plasticity of the central nervous system, and early intervention from a biologic and neurodevelopmental standpoint is important because we need to maximize the neural pathways during critical developmental windows. So in order to maximize neural development, we have to provide appropriate stimulation to the brain.

Dr. Angela Shoup:

Research by Christine Yoshinaga-Itano, this was the research that was used initially to support the universal newborn hearing screening recommendations, indicates that babies with hearing loss who receive appropriate intervention services before six months of age will demonstrate higher receptive and expressive language, express the vocabulary, and better personal, social and speech skills than children that are identified or receive intervention later in life.

Dr. Angela Shoup:

So regardless of the degree of hearing difference, if they're identified early, babies have the opportunity to develop speech along with their peers with typical hearing. The emphasis on early intervention is on providing appropriate services that most importantly allow the infant and the family access to a shared symbol-based language in order to facilitate communication.

Dr. Neeta Goli:

And then how and when did we come to develop the universal newborn hearing screening program in the US nationally, then Texas, and then specifically Parkland?

Dr. Angela Shoup:

This was a decades-long journey, but I'll try to recap it pretty quickly. Marion Downs, she was an audiologist in Colorado, who is acclaimed as the mother of pediatric audiology, and she was advocating for newborn hearing screening in the '60s. But due to a number of facts, one of these being the lack of appropriate, reliable testing technologies, newborn hearing screening was not widely adopted at that time. In the early '70s, the Joint Committee on Infant Hearing Development was convened, and in '72, they released a high-risk register. And in this high-risk register, if an infant was identified that has one of the indicators such as a family history of childhood hereditary hearing loss, a newborn infection, including rubella, herpes, CMV, or toxoplasmosis, craniofacial malformations, and specifically, those that affect the ears, low birth weight, elevated bilirubin, all of these types of problems would trigger a recommendation for screening.

Dr. Angela Shoup:

After this recommendation was made by the Joint Committee on Infant Hearing, it took a while for hospitals to start adopting high-risk register screening. And that's where Parkland comes into the picture because in 1986, Parkland started a high-risk register infant hearing screening program. And this was done with the support from the National Council of Jewish Women. Parkland expanded the high-risk register screening in 1991 to include not just infants with the risk factor, but also infants in the special care nursery regardless of risk factor.

Dr. Angela Shoup:

And then nationally, in March of 1993, the National Institutes of Health convened a consensus conference on early identification of hearing impairment in infants and young children. And their resulting statement included the recommendation that all infants receive a hearing screening by three months of age, and that this should be followed with appropriate intervention services for those who do not pass the hearing screening. And this was the impetus for universal newborn hearing screening in the United States.

Dr. Angela Shoup:

In 1997, we at Parkland convened a committee to begin planning for universal newborn hearing screening. This committee included Kris Owen and myself from audiology, Dale Talley from WISH leadership, Cheryl Aldridge, who represented the PNPs, Pam Ford as director of the Newborn Nursery, Greg Jackson and Abbot Laptook as physician leadership. Pablo Sanchez was not an official member of the committee, but he provided much guidance and was also instrumental in the addition of congenital CMV screening to the newborn hearing screening protocol.

Dr. Angela Shoup:

After we had formulated our initial plan, I then met with Ron Anderson, who was the president and CEO of Parkland at the time. He was extremely supportive of the interest in implementing universal newborn hearing screening at Parkland. He was particularly supportive of our focus on ensuring the follow-up of infants that did not pass newborn hearing screening and reinforce that management of these infants should be an emphasis of the program. Then submitted a grant proposal to Hoblitzelle Foundation, which was successful in providing the initial equipment and supplies for the program. And then in April of 1999, we initiated a pilot program in preparation of universal newborn hearing screening, which was fully implemented at Parkland as of September 1st of 1999.

Dr. Angela Shoup:

Now there was also a lot of activity going on across the nation and around the universal newborn hearing screening at this time. The Newborn and Infant Hearing Screening and Intervention Act of 1999 was introduced in March by Representative James Walsh of New York, and this led to nationwide activity to plan for implementation of newborn hearing screening programs. In Texas, House Bill 714 was passed, which required birthing hospitals to implement universal newborn hearing screening by 2000 or 2001. And then since 2000, the number of infants screened in the United States has increased from 38% to 97%. As of December of 2007, all 50 states in the United States had implemented some form of UNHS legislation.

Dr. Neeta Goli:

Okay. Quite a journey. I'm so glad to be able to talk to you both since you've been so instrumental in getting this program started here.

Dr. Angela Shoup:

Yes. Dr. Owen has been managing the program since its inception. So she has a very long history with the program.

Dr. Neeta Goli:

Yes. So now that we have this universal screening protocol, how common are we finding congenital hearing loss to be?

Dr. Angela Shoup:

The National Institutes of Health reports hearing loss to be the most common developmental abnormality present at birth. And some estimates that they've provided indicate that about 33 babies are born each day in the United States with hearing loss, other suggest one to three per 1,000 in the newborn well-baby population and two to four per 100 in the special care nursery. And then for reference, think about the prevalence of other commonly screened diseases or disorders. PKU is estimated at 0.1 per 1,000, hypothyroidism is estimated at 0.25 per 1,000, and sickle cell anemia is estimated at 0.2 per 1,000. Current CDC estimates are that 1.7 per 1,000 infants screened will have some degree of hearing difficulty. And this estimate comes from the data they receive across the United States from newborn screening programs. This estimate then increases to five per 1,000 as children reach the age of three to 17 years. So there is some evidence of a delayed onset of hearing loss in this population as well, which Dr. Owen will speak to in a moment.

Dr. Neeta Goli:

Okay. And then in terms of the actual screening protocols, the options we have are the AABR and the OAE. Could you walk us through each of these, what the acronyms stand for, how they're performed and advantages and disadvantages of each?

Dr. Kris Owen:

Yeah, sure. This is Kris. So the automated auditory brainstem response is a test that measures the auditory pathway from the opening of the ear all the way to the brainstem. And it's done with placing a gel button on the forehead, one on the shoulder and the back of the neck. The baby hears a clicking sound. It's a band of pitches that encompasses most of the speech range. And every time the baby hears a click, it records a brainstem response. And then there's an expectation of the response being a little bit louder than the noise level. And when it gets to a certain ratio, then the baby will pass the screen. But if after about 5,000 little clicking sounds, if the baby's response is not significantly higher than the noise floor, then the baby will not pass the screen.

Dr. Kris Owen:

And the OAE or otoacoustic emissions is a test. There's two different types. So there's one called transient otoacoustic emissions, and it kind of measures at a lower intensity level than distortion product otoacoustic emissions. And most of your hearing screening programs will be hopefully using the transient, which is the lower intensity level because transient otoacoustic emissions will catch hearing loss in anything that's like mild, moderate, or any... That type of hearing loss, it will catch, whereas distortion product otoacoustic emissions, they will miss the mild and just start measuring at the moderate range. So a baby could have a mild hearing loss or even a moderate hearing loss and potentially pass a distortion product otoacoustic emission screen. So that's why we want them to be using transient otoacoustic emissions if they have to use otoacoustic emissions.

Dr. Kris Owen:

I'll be honest with you. I am very pro-automated auditory brainstem response only because I would want to measure the whole auditory system, whereas with otoacoustic emissions, you're just measuring from the opening of the ear to the outer hair cells. So you're not testing the inner hair cells, you're not testing the synapses to the auditory nerve or to the eighth cranial nerve. And so sometimes we have seen, and because we use automated ABR at Parkland, we've seen babies that have had an absent eighth nerve and passed otoacoustic emissions. And so that's one of the reasons why I'm more pro-automated auditory brainstem response than I am otoacoustic emissions.

Dr. Kris Owen:

But some negatives are some things that people, you kind of wonder if you're not testing the whole auditory pathway, why would you use OAE versus automated ABR? And some of it has to do with cost. It costs quite a bit more to do the automated ABR system. The supplies are about $6 to $10 per baby, whereas if you use otoacoustic emissions, it's about $1 to $2. There is a statement out called Joint Committee on Infant Hearing or JCIH Statement, and they recommend that you only use the otoacoustic emissions in the well-baby nursery versus using them in the NICU. They don't recommend them in the NICU.

Dr. Kris Owen:

But otoacoustic emissions, how that works is you just put a little probe in the baby's ear. The baby hears a little buzzing sound and the sound travels through the outer ear through the middle ear to the inner ear. And then there's a shearing effect of your outer hair cells that produce what they call an echo. And that echo comes back out the middle ear out to your canal to the probe and your probe is picking up that echo response of the outer hair cells. So if the ear is healthy, it will produce that echo, but if it's not healthy, then you won't have a response.

Dr. Kris Owen:

So some pros and cons, I maybe talked a little bit about those, but a pro to otoacoustic emissions is that you do get some frequency-specific information, which is nice to have. And it looks at the speech range too. But some negatives of this is vernix and things like that can interfere with this screen because you're trying to measure something and bring it back out through the probe. And so you have to wait at least 12 hours before you can do the screen on a baby with that type of technology. And then also noise. Because you're picking up this very soft echo response, noise can interfere with the screening. And so we actually even tried using otoacoustic emissions because of the cost factor at Parkland, and we had to put our babies in an isolette to be able to do it because to even get those systems to run because of the noise level in the room, our ventilation system was too loud.

Dr. Neeta Goli:

So then if the baby gets the screen and doesn't pass the first time, what are the next steps?

Dr. Kris Owen:

So at Parkland, in most hospitals, if they're in the well-baby nursery, the babies will come back for an outpatient screen. The only babies that typically will not come back for an outpatient screen would be your babies with aural atresia. And in fact, Texas just recently passed in their law that you don't do a hearing screen on babies with aural atresia. And so babies with aural atresia will go directly to Children's for a diagnostic evaluation. But pretty much any other patient will come back to Parkland, to usually the birth hospital and receive an outpatient screen. It's the same exact screen that they received in the inpatient, except we do it 10 to 12 days post discharge. This is to try to rule out any type of transient thing that may be going on. If there was a little bit of fluid in the ear or the vernix that would rule that out.

Dr. Kris Owen:

And then if they don't pass the outpatient screen, we typically have them go to Children's for a full diagnostic evaluation or to any facility, any audiological facility for a diagnostic evaluation. One thing that Parkland does that other hospitals are also beginning to do is that any baby that doesn't pass the inpatient screen, they receive a CMV screen prior to going home from the hospital. And Dr. Stehel had done some research and found that about 6% of our babies were detected with having CMV. And the only reason we did the CMV screen was because they didn't pass the hearing screen.

Dr. Neeta Goli:

Okay. So important not to miss those.

Dr. Kris Owen:

No.

Dr. Neeta Goli:

And just one point I just wanted to clarify for our listeners, what Dr. Owen is referring to is if the baby does not pass the first screen, then the screen is repeated the following day. And so this is all if the baby does not pass both screens.

Dr. Kris Owen:

Right.

Dr. Neeta Goli:

So for our listeners, if they don't pass the first one, we just recheck the next day.

Dr. Kris Owen:

Yes. And so, probably when audiology rechecks in the next day, then we will send them on to for the outpatient screen. Now, if they're in the NICU, if the babies are in the NICU for greater than five days, then those babies do not receive an outpatient screen. All babies will go directly to Children's for a full diagnostic evaluation.

Dr. Neeta Goli:

How common is it for babies to not pass both screens in the nursery and then come back and pass in the outpatient setting?

Dr. Kris Owen:

For us, it's about 50% of the time the babies will pass the outpatient screen. So it's a significant number. But once those babies go on to Children's for a full diagnostic evaluation, probably about 85% to 90% of those babies will have some type of auditory impairment. So if they do end up getting to Children's having to go on for the diagnostic testing, the probability of there being some type of auditory impairment is significantly higher.

Dr. Neeta Goli:

I see. Okay. And then other than CMV, you said the most common things we would see or identifiable factors we would see would be genetic causes?

Dr. Kris Owen:

Yes. Our most common risk factors are family history. We see that a lot. Also extended NICU stay where they have a very low birth weight. Also, if there's more than one thing going on, like say they have very low birth weight and they also were exposed ototoxic meds for five days or more, then their risk of a change in hearing or a delayed onset of hearing, we see that quite a bit.

Dr. Neeta Goli:

Okay. And then can you tell me a little bit more about the delayed onset hearing loss?

Dr. Kris Owen:

Sure. We have a program at Parkland and a lot of other hospitals are starting to ramp up on this because of what Dr. Shoup mentioned about there being a higher incidence later on in life of seeing a change in auditory statuses. We have something called a delayed onset program. And we starts with when the baby passes the screen, we give the family some developmental milestones. It is in their pass letter and we just ask the families to check and make sure that their child is hitting the developmental milestones. Also, the medical home is also doing checks to make sure babies are hitting their developmental milestones. And then if they're not, or if the parents get concerned, then we're recommending they do another test.

Dr. Kris Owen:

But if a baby has like a family history of hearing loss, or they were given ototoxic meds greater than five days, or if they were in the NICU for greater than five days, these are some of our common risk factors that we would give the family a letter. The letter tells the family that their baby passed the test, yay, but that they need to come back for some follow-up testing just to make sure that nothing's changed.

Dr. Kris Owen:

And so typically right now, the Joint Committee on Infant Hearing put out a new statement and they recommended that all of these, with some of these risk factors, like family history, the NICU, the ototoxic med, they did change that. It used to be if they got any type of ototoxic med, like gentamicin, for example, they would have to come back for follow-up testing. But now it has to be a full course, which would be five days or more. And then if they had any utero infections like herpes, exposure to HIV or Zika, then those patients will come back by nine months.

Dr. Kris Owen:

So how we do it at Parkland just to make it simple is we have everybody come back at six months of age. And then based on their delayed onset respect, it determines how we follow them from there. But all of our families will get a letter recommending that they give this letter to their primary care provider, let them know that they have a risk factor for a change in hearing, and then that they needed some follow-up testing. And then the family home will make the follow-up appointment.

Dr. Neeta Goli:

Okay. Is there anything else that either of you wanted to bring up today that we haven't gotten a chance to cover yet?

Dr. Kris Owen:

I think we wanted to just mention the importance of following patients and making sure if there's any parental concern or if there's any risk factors to definitely monitor and make sure that the kids are hitting their developmental milestones. And if not, to go ahead and recommend some more testing be done or recommend that we repeat the testing. And then also just talking about, have you heard about the 30-million-word gap? Have you heard of that where just talking to your baby in a conversational way helps to really impact your baby's language development? And so one thing we spend time with is talking to our families when they come back for that six months follow-up about how important it is to talk to them. That they learn a lot more from their families talking to them than they do from the TV.

Dr. Kris Owen:

And so if they were to read a book and then the TV were to read the same book, the child would have learned more or grasped more from their parents reading it than they would hearing it from the TV. And so we talked to the families a lot about talking with their children, also having the siblings talk to them to help their baby's brain grow and also help them to develop speech and language. So those are some things that we talked a lot with families about and I would encourage everybody to. And our families are so excited to know that they can help their baby's brain grow by just talking to them.

Dr. Neeta Goli:

Yeah, and that's such a great tie in to reading to your baby is there are so many programs crafted around this. So Reach Out and Read is a program that provides books for pediatricians to provide to their families, to include the anticipatory guidance about reading to their babies for speech and language development. So really wonderful interventions that we have. In terms of reading to your baby, I've heard commentary about dialogic reading. Is that how it's pronounced? Is it dialogic, dialogic?

Dr. Kris Owen:

That sounds good.

Dr. Neeta Goli:

I'm not sure exactly how it's pronounced. I've heard some information about dialogic reading. Would you be able to speak to that in terms of how that works?

Dr. Kris Owen:

Yes, that's what they were saying. For the 30-million-word gap, they were saying, don't just say words like, you know how some people will point to an object and say, "This is a ball, that's a ball." They talk about it more being a conversational type thing. Kind of having conversations with your children, talking about what you're doing. "I'm stirring the cake batter, we're going to pour it in the pan." And it's going to make it kind of using more of a dialogue versus just saying words and pointing to different pictures. They say that children, their comprehension level is a lot greater if you spend time doing that with your child than you would if you... Then when they hit kindergarten, a lot of kids they'll evaluate, and kids that have had that opportunity to have the dialogic reading and the dialogue conversations with their families and their families talking with them more in a conversational manner versus point to this picture, point to that picture kind of thing, that they are the ones that their comprehension levels are a lot higher than the ones who haven't had that opportunity.

Dr. Neeta Goli:

Well, thanks so much for this great discussion today. To end the episode, do either or both of you have any additional advice for our listeners while they're taking care of newborns?

Dr. Kris Owen:

No, mostly just talking to their babies. And just if they are concerned in any way, to just talk with their pediatricians to determine if additional testing is needed. And that the earlier we can do something about it, the more opportunities the child has for different modes of communication. So early intervention is key.

Dr. Angela Shoup:

And I think that the only other thing we might add is that Texas does have the Texas EHDI program, Texas Early Hearing Detection and Intervention Program. And they have a lot of information on the Texas website that includes information for health care providers. They also have a database that Parkland and all of their other hospitals that screen are required to enter their data about their babies screened into the database, and audiologists who do follow-up testing enter the test results on those babies that did not pass the newborn hearing screening. And as a medical provider, as a medical home, you can reach out to this state and get an account so that you can log on to that system and monitor your patients' hearing screening test results through that system.

Dr. Neeta Goli:

Okay, that's a useful resource for us to know about. Thank you so much for all this information and thank you both for joining us today.

Dr. Kris Owen:

Thank you for having us. We really appreciate the opportunity.

Dr. Angela Shoup:

Thank you so much.

Dr. Neeta Goli:

Thanks for listening to Newborn News. We hope you join us next time. If you like what you hear, make sure to subscribe and leave us a review. If you have questions, comments, feedback, or suggestions for future episodes, please email me at newbornnews@utsouthwestern.edu. As a reminder, this content is educational and is not meant to be used as medical advice. Views or opinions expressed in this podcast are those of myself and my guests and do not necessarily reflect the views of the university.