Transcription:

Melanie Cole (Host): Welcome to UAB Med Cast. I'm Melanie Cole. And today we're discussing hypoglossal nerve stimulation to treat obstructive sleep apnea. Joining me is Dr. Kirk Withrow. He's the Director of Salivary and Sleep Surgery in the UAB Department of Otolaryngology at UAB Medicine. Dr. Withrow, it's a pleasure to have you join us today. I'd like you to start by giving us a brief overview of obstructive sleep apnea and the trends that you're seeing. And tell us just a little bit about who's at risk.

Kirk Withrow, MD (Guest): Sure thanks for having me. Obstructive sleep apnea is the most common form of sleep disordered breathing, and essentially is a pathologic amount of obstruction due to collapse of the airway and loss of muscle tone. And that leads to a disordered sleep architecture and desaturation in the blood oxygen levels which in turn leads to quality of life issues, such as snoring, cognitive deficits, excessive daytime sleepiness, and then health risks that we're pretty aware of including high blood pressure, you know, heart rhythm issues, heart attacks, and stroke risks.

Host: We're certainly learning more about the link between sleep disorders and obesity and diabetes, as you say, so many other things. So let's talk about first-line treatments because we really want to get into our hypoglossal nerve stimulator. So just tell us about conservative measures you would try first. Speak about C-PAP, medications, first-line treatments, and adherence to these treatments and specifically C-PAP.

Dr. Withrow: Sure C-PAP is as far and away the, the first line treatment. It has some significant advantages over most other treatments in that it can be titrated in the sleep lab and be shown to be effective at treating sleep apnea in a given patient. And unlike our other options where we have to kind of work backwards from that, and we'll talk more about that in a minute, I would assume, but the issue that C-PAP has in treating sleep apnea is that once they arrive at a set effective level of therapy, tolerance is, is the, the key question. And it's about 50, 50. On average, you know, a sleep lab that is very diligent might be able to get their patient compliance up to maybe 60 or 70%.

But the fact of the matter is that even though it is effective, not everyone can use it.

Host: Yeah, so we've seen a lot of literature on that and the adherence issue. So, barring all the rest of those things, tell us about hypoglossal nerve stimulators. How do they work? Tell us a little bit about this procedure and the device.

Dr. Withrow: Sure. Oh, well, I'll start with what we've had available just prior to that. And we have surgeries that can open the airway by moving the skeleton. So jaw surgeries to increase the amount of room for the tissue in the airway or surgeries to remove or alter that tissue, like taking out tonsil tissue and that sort of thing. Those can be effective, but as you would imagine, they're considerable procedures to go through. And so the more recent therapeutic option, that's been, been very impressive with its ability to treat it, but also with the lack of morbidity is hypoglossal stimulation and essentially it involves a nerve stimulator specifically to the hypoglossal nerve, that allows the addition of muscle tone, which is what is lost when we go to sleep to prevent the airway collapse. And in fact, to open the airway. Even though it's attached only to the hypoglossal nerve at this point, that moves the tongue, which is in turn attached to other structures, such as the soft palate and the epiglottitis. And therefore it can be almost a complete upper airway stimulation in many instances.

Host: Speak about patient selection, who makes a good candidate for this procedure?

Dr. Withrow: So as with most surgeries for sleep apnea, body weight is important. There are, there are practical and insurance considerations as far as that goes. Most surgeries are felt to be a lot less effective when you get above a BMI of 30. We have pretty good data up to 35 with the hypoglossal stimulators.

So, you know, certainly above that, we have to really encourage weight loss. Private insurance will cover this procedure up to a BMI of 32. Medicare covers it up to 35. So that is one of the big criteria. Other criteria that are of significant importance, including obviously having sleep apnea and at a mild or above level.

So 15 events and up typically is where, where this therapy is indicated. A patient can't have too much central sleep apnea. That's a fairly uncommon finding relative to obstructive apnea where the brain is essentially not telling the patient to breathe as opposed to obstructive apnea, where patient is trying to breathe, but the airway is collapsing and preventing that air flow.

And then the last criteria and maybe the most important one for the current device that we have available is how the airway collapses when we do a sleep endoscopy. A sleep endoscopy is a 20 to 30 minute procedure where we give a patient sedation and use a flexible scope to watch the airway collapse.

And that in turn tells us exactly what is occurring during these episodes of obstruction and apnea. And in turn will a stimulator effectively treat that.

Host: It's fascinating. What an exciting time to be in your field. Dr. Withrow speak to other providers about the changes that you've seen in patients once they start using the hypoglossal stimulation. Tell us about your outcomes.

Dr. Withrow: As far as the current device, that's FDA approved is the Inspire device. And to date, I've placed around 300 or so of them. And we see anywhere from probably 75 to 80% reduction in the severity of apnea. Quality of life improvement is, is very, very high, as is patient satisfaction. It's probably on the order of 95%. As far as you know, the patient's acceptance and approval of this therapy and even recommendations to other patients. So it's been pretty remarkable. That's far better than we can see with most of our other surgeries. And given that this isn't meant to replace C-PAP that's it's even more, more important I think because you're taking patients who are otherwise completely untreated and can give them a very acceptable and tolerable means with very high compliance.

We've rarely see people who don't use it, you know, the entire night of their sleep because there's not a whole lot that they have to do. They just turn it on and it does its thing.

Host: Wow. As we wrap up, Dr. Withrow tell us a little bit about the procedure itself and recovery and speaking to other providers, what would you like them to know about hypoglossal nerve stimulation and referring patients to the experts at UAB Medicine?

Dr. Withrow: Well, I would say as far as the, the procedure itself is a, an outpatient procedure it's done under general anesthesia. It takes me approximately an hour to an hour and a half to do. There's very minimal recovery, minimal pain with it, certainly relative to our other surgeries. There are other devices in the works, we have a couple of others that we're doing a trial on. There's a DREAM trial, which is for a device called the Genio device, which is a different type of a hypoglossal stimulator and the OSPREY trial, which is for a device called the Aura device again, another hypoglossal stimulator, which just adds more options for patients and more potential patients that can be treated.

So I think that the main thing for referring providers certainly, you know, if they are specifically interested in Inspire or hypoglossal stimulation you know, those criteria that we went over before are the main ones that are used in that regard. Insurance, pretty much universally approves that therapy as long as we meet the criteria.

But you know, we're certainly happy to see other patients, whether they are you know, clearly a good Inspire candidate or hypoglossal candidates. Sometimes we can help them to become a candidate for that. Or we do always have other options that we can pursue to try to get their sleep apnea under better control.

Host: Great information. Thank you so much, Dr. Withrow for joining us today. And a physician can refer a patient to UAB Medicine by calling the mist line at 1-800-UAB-MIST. Or by visiting our website at uabmedicine.org/physician. That concludes this episode of the UAB Med Cast. For updates on the latest medical advancements, breakthroughs and research follow us on your social channels. I'm Melanie Cole.