Unlocking the Mysteries of Sleep Apnoea: From Diagnosis to Cutting-Edge Treatments

Dr Gavin Nimon: ​[00:00:00] Sleep apnoea is a common but frequently undiagnosed condition which not only affects the quality of life but also poses serious health risks including cardiovascular complications, metabolic disorders and impaired cognitive function. Understanding the pathophysiology, identifying key symptoms and mastering diagnostic and treatment approaches are essential for any medical practitioner.

In today's podcast, we're going to explore the critical importance of recognising and managing sleep apnoea to improve patient outcomes and overall health. In the first part, we're joined by Dr Sanaz Lehman, a respiratory and sleep physician from Adelaide. Later, we're joined by Professor Simon Carney, an ENT surgeon, who's going to discuss the role that surgery has to play in sleep apnoea.

G'day and welcome to Aussie Med Ed, the Australian medical education podcast, designed with a pragmatic approach to medical conditions by interviewing specialists in the medical field. I'm Gavin Nimon, an orthopaedic surgeon based in Adelaide, and I'm broadcasting from Kaurna land. [00:01:00] I'd like to remind you that this podcast podcast players and is also available as a video version on YouTube.

I'd also like to remind you that if you enjoy this podcast, please subscribe or leave a review or give us a thumbs up as I really appreciate the support and it helps the channel grow. I'd like to start the podcast by acknowledging the traditional owners of the land on which this podcast is produced, the Kaurna people, and pay my respects to the Elders both past, present and emerging.

Dr Gavin Nimon: I'd like now to introduce Dr Sanaz Lehman, a Respiratory and Sleep Physician from Adelaide.

Having migrated to Australia from Iran in 1991, She studied medicine at the University of Adelaide and undertook basic physician training at the Royal Adelaide Hospital, completing respiratory and sleep medicine at Flinders Medical Centre, then the Repat General Hospital, then later on the Royal Melbourne Hospital.

She's worked as a Respiratory and sleep physician at the Queen Elizabeth Hospital for over 13 years, with sleep medicine being her number one passion throughout her career. In 2022, she established Complete Sleep Care, a medical sleep centre which concentrates [00:02:00] on the diagnosis and management of sleep disordered breathing.

Today she is going to talk to us about the importance of sleep and the disorder of sleep apnoea, a growing problem in today's society. Welcome Sanaz. Thank you very much for coming on board.

Dr Sanaz Lehman: Thank you. Thank you for having me.

Dr Gavin Nimon: It's brilliant to have you here. I wanted you to go through, first of all, and explain to me why sleep is so important.

Dr Sanaz Lehman: , from a simplistic point of view, sleep is a very good rest. So physically, it is very important in resting the body, but it's becoming more and more important that not only that from a mental point of view, from a psychological point of view, sleep is very important. Sleep is very important in consolidating memory in maintaining our mental health.

Controlling emotions, monitoring behavior. Sleep is important in maintaining immune system. it's multi layered how important sleep is. And that's becoming more and [00:03:00] more important and apparent in the sort of modern culture. And people are becoming more aware of sleep.

And it's importance.

Dr Gavin Nimon: What actually happens in the brain when people sleep?

Dr Sanaz Lehman: Yeah, so there are different stages of sleep in lighter stages of sleep. We are just going into sleep and our brain is entering the resting phase. And then it is the deeper stages of sleep, a slow wave sleep and also REM sleep that have been shown to be very important in essentially actively resting the brain and helping with consolidating memory, helping with improving the immune system with monitoring or Stabilizing behavior.

Sleep is probably the easiest way to put it is an active process to rest the brain and rest the body.

Dr Gavin Nimon: So what are the phases of sleep then?

Dr Sanaz Lehman: When you sleep, you go through four to six phases, and each phase [00:04:00] has four stages stages one and two, which are, as I said, when you first sleep you go through stage one, which is about five, seven minutes, then you go to stage two, it's a bit longer, then you have a stage. 3 and 4, which is slow wave sleep or deep sleep, and that's generally longer.

And then you have REM sleep. Each cycle about 90 to 120 minutes. And you usually have 4 to 6 cycles per 24 hours or per night.. REM sleep usually is about 20 to 25 percent of total sleep time. And historically it was thought that it's REM sleep that's only important in terms of, that's the stage that we dream in.

And it was thought that's the deep stage of sleep that's important in resting the body, resting the mind. But a slow wave sleep is also as important, than REM sleep. .

Dr Gavin Nimon: Okay. So I understand sleep apnoea is a big issue [00:05:00] nowadays in today's society and that affects sleep.

Dr Sanaz Lehman: So sleep apnoea essentially means when you stop breathing. The most common type that is the bulk of our clinical work is obstructive sleep apnoea. And in today's society with increased risk of obesity, , obstructive sleep apnoea is becoming more and more common. It is quite common if you look at men, It could be that something as much as 20 to 25 percent can be the prevalence of sleep apnoea

and obstructive sleep apnoea means when the upper airways collapse either completely or partially during a sleep. Central sleep apnoea is a bit more complicated and that refers to when the brain doesn't actually send signals for you to breathe. So it's got a central cause for [00:06:00] it. But obstructive sleep apnoea, as I said, is more common and it does make the bulk of our practice as a sleep physician.

Dr Gavin Nimon: right. Now you're saying obstructive is the most common and what are the main factors for that? You've already mentioned obesity. Are there other factors as well

Dr Sanaz Lehman: So the three main causes are obesity, so BMI of greater than 30. Men are generally at a higher risk, and that could be, again, anatomical and hormonal, and age. As people get older, risk of sleep apnoea increases. Other causes, women as they get older. older and go through menopause and lose the protective effect of estrogen also increase the risk of sleep apnoea.

There is obviously a genetic predisposition in terms of differences in anatomy. So yeah, these are the main risk factors. .

Dr Gavin Nimon: Okay. Why would you get [00:07:00] a central cause then? Is that related to previous strokes

Dr Sanaz Lehman: There are different causes. The most common cause that we see clinically, especially given the cohort of the patients that you see in a respiratory and sleep clinic, is heart failure. So patients with heart failure have what we call cheyne-stokes respiration, which is a rhythmical pattern of breathing and, that's the most common cause of central sleep apnoea.

Other causes pathology such as a brain tumor or a stroke. Less commonly things like congenital causes. And another common cause of central sleep apnoea that you should always think of at the back of your mind is medications. That can also cause central sleep apnoea.

Dr Gavin Nimon: And what are the medications you need to look out for in that scenario?

Dr Sanaz Lehman: Essentially things that suppress your breathing, the most common would be benzodiazepines. Yeah, so [00:08:00] that would be the most common thing that you see. And also the comorbidities to look out for that are associated with sleep apnoea include things like high blood pressure, So patients that, again, that you see in the cardiac and respiratory patients that you commonly see that, have cardiac risk factors such as ischemic heart disease, high blood pressure atrial fibrillation, COPD.

These are all risk factors that, are associated with sleep apnoea.

Dr Gavin Nimon: So they're an association. Does the atrial fibrillation itself cause sleep apnoea, or does the sleep apnoea cause actual fibrillation as a way of identifying it?

Dr Sanaz Lehman: It is generally thought that it is the sleep apnoea that contributes to atrial fibrillation. It is not so much that sleep apnoea causes atrial fibrillation or sleep apnoea causes high blood pressure. And if you treat sleep apnoea, then these things are resolved and treated. It is a [00:09:00] contributing factor. It is a risk factor.

It is like smoking contributes to high blood pressure. So it's a risk factor. So if you address this risk factor, then you can control the. High blood pressure better.

Dr Gavin Nimon: Okay. And on the scenario of age and lack of estrogen that almost implies as a collagen laxity in the soft tissues, which also can be a factor in causation of obstructive sleep apnoea, is it?

Dr Sanaz Lehman: That is, yes. That is my understanding that once , the estrogen goes, then the muscles become more lax and more prone to collapsing.

Dr Gavin Nimon: So would things like Ehlers Danlos and other conditions like that also be a risk factor for , obstructive sleep apnoea too?

Dr Sanaz Lehman: Absolutely, yes. Absolutely. And I do have patients with those conditions that do have obstructive sleep apnoea.

Dr Gavin Nimon: Excellent. So what symptoms do you get when you get sleep apnoea?

Dr Sanaz Lehman: The most common presenting complaint is a snoring. But I always say just because you snore doesn't mean you've got sleep apnoea. But [00:10:00] people with sleep apnoea generally snore. So patients come in, their partner is complaining that they snore.

Their partner may complain that they stop breathing. And that is one of the concerns that a lot of people have, and they are very worried. Scared of it. Then things like that, tired during the day, they find that when they wake up with a headache. They don't find their sleep refreshing by early afternoon.

They are tired. They have to have a nap during the day. So the main symptoms, or presenting complaints are snoring, partner says they stop breathing. And they're tired during the day.

Dr Gavin Nimon: Okay, how do you actually further assess it? Obviously, there's a lot of fitness watches out there which try and monitor sort of things like that. Are they useful

Dr Sanaz Lehman: No, they are not useful. I don't generally put any emphasis on those. I do get a lot of patients coming in saying their oxygen level is abnormal because of that. Or they don't have enough deep sleep. But I don't put any emphasis on fitness trackers. [00:11:00] No. How you further assess it, there are questionnaires that you use.

Epworth sleepiness score (ESS) that has 8 questions. That's a question of sleepiness. That's a standardized way to see how sleepy the patient is. The problem I find with it is very subjective and also the patients, can not be truthful for various reasons, including they're worried about losing their license or, concerned about their jobs.

But it's a rough guide of how sleepy you are. So it's eight questions. You rate them, whether there is no chance, small, moderate, severe in various scenarios, such as What's the chance of you falling asleep after you eat? What's the chance of you falling asleep if you're watching TV? If you're reading in the afternoon?

If you're stuck in traffic? If you're a passenger in a car, long drive? [00:12:00] And you then, Rate these as 0.1.2. or 3, and then you add up. Anything less than 8 is thought to be normal. If a patient scores 8, then they are at least mildly sleepy. And then there are other questionnaires that you look at the risk factors for the patients in developing sleep apnoea.

The main ones that I use are Stop-Bang which is do they snore? Are they tired? Do they stop breathing? Male or female? Comorbidities like high blood pressure, BMI. And neck circumference. I should mention that the size of the neck is also a risk factor for sleep apnoea. Or OSA 50, which again looks at your age, do you snore, stop breathing and so these questionnaires assess the risk of sleep apnoea.

And then with combination of these , you get , a profile [00:13:00] and a picture of how sleepy is the patient, does the patient have sleep apnoea, and then you can decide whether to proceed to the sleep study or not. Having said that, as I mentioned, ESS can be quite inaccurate and there could be patients who are skinny, who may not snore a lot or they sleep alone and there is no comments about snoring or stopping breathing and these people again need to have a sleep study.

, so accurate clinical assessment. Examination and clinical judgment are very important in who you decide to proceed to a sleep study.

Dr Gavin Nimon: For someone who does sleep on their own and they don't know if they snore and they're not that tired at night, how would they be identified as someone who could have sleep apnoea?

What would bring them to your attention in that scenario?

Dr Sanaz Lehman: The ones that in terms of risk factors, if someone has high blood pressure that is [00:14:00] difficult to control and they are on two or more medications and despite that their blood pressure is high, I think

that's very important to screen them for sleep apnoea. Atrial fibrillation is another thing, especially in the younger people that, there is no definite cause for it.

Then again, it's important to have a look at sleep apnoea. And then even if they are not tired, but they wake up with a headache or they have difficulty concentrating, they have difficulty with their memory Another thing is if their sleep is fragmented, if they wake up a lot during the night.

We get a lot of patients, especially a lot of men that come and they wake up a lot to go to the bathroom and they've been investigated and they've seen a urologist. There is no cause for it. They are not diabetic. And again, that could be a symptom of sleep apnoea.

Dr Gavin Nimon: Okay, so then obviously, once you suspect that sleep apnoea is [00:15:00] occurring, I presume you need to investigate it. Apart from a sleep study, are there any other pre investigations you might do,

Dr Sanaz Lehman: a lot of patients that I see, obviously, they've already had those basic tests. Because a lot of patients present to their GP, I'm tired, I don't know why. So basic bloods, checking their hemoglobin level, iron studies, thyroid sometimes, Checking things like is the patient going through menopause, for example, hormone levels.

So just basic blood obviously is important. And once the bloods are okay, and if anything comes up out of the blood, if any further testing is done, is needed, once there is nothing You know, jumps at you, then that's when they are referred to me. And my first line of investigation is probably a home sleep study.

And I always describe it as it's non invasive. It's an easy test, and with a home study, you do it [00:16:00] at home. And with the new sleep kits, they are very easy. Noninvasive. They are very easy to attach. Everyone can do it. So it's a very easy test. It's a very easy screening test. And it gives us a lot of information.

Dr Gavin Nimon: I have actually been through one of these at one stage. And because I sleep on my front and it's almost like it was designed to tie me up while I tried to turn over in bed. How easy, is it

because it certainly did seem quite tortuous to try and work into a position to be comfortable.

Dr Sanaz Lehman: I guess that's one issue. You can still sleep in any position, especially on your side, but a lot of patients think they shouldn't. So they end up sleeping. more on their back. And then when you see them, you say your sleep apnoea is worse when you're on your back.

And they say, actually, I don't sleep on my back usually. So I guess that's one of the drawbacks. Patients can sleep on their sides especially, and you get information quite accurately, but [00:17:00] they think they shouldn't. But I always explain to them just do what you do normally. You can sleep however you want.

You can get up in the middle of the night. . Detach, go to the bathroom and yeah.

Dr Gavin Nimon: Now what sort of data does this sleep study give you that helps you diagnose sleep apnoea?

Dr Sanaz Lehman: The data that the sleep study at home gives us is quite Accurate, and it gives us a lot of data. It gives us data about the sleep stages, so we get the sleep architecture quite accurately. It gives us information about the flow of air, so we can identify when there is an apnoea versus when there is a hypapnoea oxygen saturation.

 There would be a heart monitor, so you get a very basic ECG strip. So if you have an abnormal heart rhythm, for example, it's picked up. And it also gives us information about body position. [00:18:00] As well as movement of the legs, because another thing to watch out for is things like periodically movement that again can cause sleep fragmentation.

And there is also a sound recorder so you get the snoring.

Dr Gavin Nimon: Okay. Once you've got that sort of assessment and you've taken into account the different scores, how do you decide who's got sleep apnoea and who's just got basic snoring and it's not really important? What's the sort of cut off to actually make a formal diagnosis?

Dr Sanaz Lehman: You've got an apnoea hypopnea score, and that's given as an index. Basically anything up to 5. AHI of 0 to 5 is normal, 5 to 15 is mild sleep apnoea, 15 to 30 is moderate, greater than 30 is severe sleep apnoea. , treating sleep apnoea is a bit more complicated than that you need to take into account how tired the patient is, [00:19:00] and then is the sleep apnoea worse or when they are on their back?

Is there sleep apnoea worse when they are having REM sleep? Is the sleep apnoea affecting the sleep architecture? Are there a lot of arousals as a result of the sleep apnoea? Is there significantly reduced REM or slow wave sleep? So it is not so much that AHI is greater than 30 we need to treat, less than 30 we don't treat.

The other thing is you need to look at other comorbidities. If they've got difficult to control high blood pressure or if they've got atrial fibrillation then you would be more keen to treat a milder degree of sleep apnoea. So it actually becomes quite complicated.

Dr Gavin Nimon: And that's obviously why you've done so much specialist training in this area and involving a sleep physician is important. If the person is diagnosed with sleep apnoea. Obviously there's different forms of treatment, both lifestyle changes to more invasive equipment and [00:20:00] also surgery, which we'll cover later on in the podcast with Professor Simon Carney.

Perhaps you can outline what the different aspects of treatment are for me, please,

Dr Sanaz Lehman: Absolutely. Yeah, so as I said, treatment of sleep apnoea is very complicated and you don't really realize how complicated it is until you do it day in, day out and you see a lot of patients. So the basic treatment of sleep apnoea, the most, The gold standard treatment of sleep apnoea is CPAP and weight loss.

So the first advice, especially the patient cohort that you see generally have a BMI of greater than 25. So they are overweight. So the basic thing the first advice is losing weight. Losing weight helps, irrespective of whether you're going to put them on CPAP or not. If you're going to put them on CPAP, if they lose weight, they'll probably need a lower pressure.

And even if they want to have conservative treatment, again, Losing weight will help. So weight loss is the number one advice, [00:21:00] but it's probably the most difficult thing to adhere to and it is a long term goal as opposed to it doesn't happen overnight. So it's, lose weight, great, but it's not going to happen overnight. If somebody has mild sleep apnoea and the problem is it happens when they're on their back. So when they're on their back, their AHI goes up to 70. When they're not on their back, their AHI goes down to 2. Their overall AHI is, say, 15, 16. Then you can advise them to not sleep on their back.

That becomes a bit more difficult when you have older population and they've got arthritis in their shoulders, in their hip, because you need to exclusively sleep on your sides. So that becomes again a bit more complicated. But there are devices that help you and not sleep on your back. Historically, we would advise people to, between their shoulder blades, sew in a pocket, put a tennis ball in it.[00:22:00]

And then every time they're rolled on their back, they would be woken up. And in fact, some sleep centers were selling those t shirts. But now there are more sophisticated devices. There is something called night shift that you either wear around your neck or around your chest. Every time you go on your back, it vibrates.

And the good thing about it is it's more often than not, it doesn't really wake the patient up. They just change position. And you can download it and see whether it's been successful or not. Avoiding sleeping on your back is one of the conservative measures, and compared to CPAP, it's a good compromise.

It's cheaper, it's easier. Another kind of conservative measure is mandibular splints. Which is done by, people sometimes buy them online, but , you definitely need to see a dentist to assess your suitability. It [00:23:00] is an active splint, and I describe it to patients, it's like children wearing braces.

It actually pulls your jaw forward and increases the space of in your pharynx. The main role I see for mandibular splint is in younger population, when their main concern is snoring, and they've got mild sleep apnoea, because it gets rid of the snoring. With sleep apnoea, roughly, it halves the severity of sleep apnoea.

If your AHI is 18, It comes down to nine. You'll still have sleep apnoea, but it will be milder. It's really reserved for those patients that are young, they snore, they don't have very bad sleep apnoea. It's, another role would be in patients that do have bad sleep apnoea, but they can't tolerate CPAP.

, you've done everything you can, they can't tolerate CPAP, and then that's your last resort. So for those [00:24:00] patients, I would say it's an inferior second because it's not an accurate treatment. Generally what I recommend is go on the mandibular splint once you're used to it.

Dr Sanaz Lehman: We do a sleep study to see how bad your sleep apnoea is. And then as I mentioned, CPAP is the gold standard because it gets rid of your sleep apnoea, it gets rid of the snoring and that's the treatment for people who have moderate to severe sleep apnoea. Then you get into surgical treatments that I know you're talking to Professor Carney and that definitely has a role too, and I would let him elaborate on that.

It

Dr Gavin Nimon: Perhaps you can explain different types of sleep apnoea machines there are. I presume that they're quite common and people tolerate them fairly well and actually get a good benefit from them as well.

Dr Sanaz Lehman: is amazing how their public opinion has changed. Most patients especially in the older population, have a [00:25:00] very good idea of what a CPAP device is. In a lot of cases, their partner has it and they have friends that have it, and they all say how it has changed the lives of

people that they know. So most patients are not scared of it. You do get the cohort of patients, especially in the younger population, that think it is quite big and clunky. And there are some people that tried it 10, 15 years ago, couldn't tolerate it. have come back because they're tired, they're desperate, and they'd be pleasantly surprised how far things have come along.

The area of sleep apnoea and CPAP devices have gone through a lot of progress over the last 10, 20 years. So those clunky, big, noisy machines, those massive masks don't even exist now. The masks can be quite delicate, they could be quite small and [00:26:00] Non invasive. Machines are very quiet, such that if a patient snores, then when they go on CPAP, the partner is so thankful.

So the machines essentially don't make any noise.

Dr Gavin Nimon: That's good to see. And what about when they say to you, look, apart from getting a better night's sleep, what are the main advantages of it? And I presume it's just going to be purely the reversal of these things we've already talked about, but , what's your big selling point for saying someone should have their sleep apnoea treated for them?

Dr Sanaz Lehman: It , firstly, it improves your quality of life. Because you will feel so much better during the day and you will be more rested, which means all those things that we talked about in terms of concentration, memory, managing emotions even things like, immune system, they all will improve because your sleep will be more consolidated and you'd be more restful.

And in a lot of patients, especially the ones that have quite bad sleep apnoea, I do tell them this is going to [00:27:00] revolutionize your life. And sometimes when a lot, because what happens is that ESS is not really, doesn't really color correlate with AHI. So you can have really bad sleep apnoea, but just have an ESS of seven or eight.

And what I tell them is you don't know any different. So when you actually go on CPAP and realize how much better you're feeling It will just revolutionize your life and it's amazing the patients that come and tell me that and they just are so thankful that sleep apnoea has been diagnosed and treated.

And then from a medical point of view, from a comorbidity point of view, obviously, It is important. I do describe it as a cardiovascular risk factor because it is a risk factor as we talked about for high blood pressure and as a result for ischemic heart disease. It is a risk factor for things like atrial [00:28:00] fibrillation.

It's even been shown in patients with diabetes. Control of blood sugar improves. When sleep apnoea is treated. It is being associated to increased risk of stroke. Patients with COPD are a very important cohort of patients to pick up if they have sleep apnoea because it does improve, because improving your breathing at night, your oxygenation at night, your blood gas status, it is all important in improving your health.

 So from a medical point of view, from a risk factor point of view, it is also very important. And with a lot of the younger people that's a very important thing. So if somebody who is 40, 50 comes with a severe sleep apnoea, or even with a moderate sleep apnoea, it's very important for that to be addressed.

Because they've got another 40 years ahead of them. And this risk factor just [00:29:00] sitting there, obviously it's important for that to be addressed.

Dr Gavin Nimon: Brilliant. What percentage of people in Australia would be diagnosed if they were all tested

Dr Sanaz Lehman: . I guess overall it could be 5 - 10 percent of the population. And especially with increasing obesity, lifestyle it is becoming more and more common. But if you look at special cohorts, older people, Men looking at BMIs, then that could go up to 25%. So depending on the people , that come to you at a specialist level then yeah, it is much more common.

Dr Gavin Nimon: And how effective is weight loss in those people? We talked about weight loss being important. What's the chance of someone losing weight actually reversing the sleep apnoea? Or does it just help to control the symptoms?

Dr Sanaz Lehman: No, it is effective. I would say it is effective. And I always tell people, if you lose 10 percent of your body weight, [00:30:00] we will repeat your sleep study. The thing with weight is, if you lose weight or gain weight, it has a huge effect on the amount of adipose tissue around your neck and the pressure that will be on the upper airways.

So I do have patients that have very bad sleep apnoea, they lose weight. You do need to lose a significant amount of weight, so as I said, at least 10%. And they don't have sleep apnoea anymore or it becomes milder. And then with the milder amount of sleep apnoea, then we can work around it. If they avoid sleeping on their back,

so then you can work around it, and if they really don't like CPAP, then that's a very good motivation. But what I find is with a lot of the younger population who are not necessarily overweight, but they have a lot of REM related sleep apnoea, treating it would have a huge effect in how they're feeling.

What I do recommend with people, even if [00:31:00] their sleep apnoea is not, Very bad is have a trial of CPAP, see how you can feel. And sometimes it really, as I said, just changes their lives.

Dr Gavin Nimon: Now you've mentioned a couple of times about compliance. What percentage of people don't tolerate the CPAP machines? It sounds like most people do because they're so better off afterwards. But is there a percentage that don't?

Dr Sanaz Lehman: Most people do, especially when you see people in the outpatient setting that they've come willingly and they want to sort it out, they do. And if they go through purchasing the machines and they are not very cheap, so they do tolerate it. Occasionally, you do get people that do not tolerate it, and there could be a legitimate reason for it.

One of the common reasons is nasal pathology, so blockage of nose for whatever reason. So as part of my workup for these patients, when I'm doing a sleep study, [00:32:00] because a lot of them come to do a sleep study, and they say, I've got a blocked nose. That's a very common complaint, and I usually scan their nose and sinuses, and if there are issues, then I send them to an ENT specialist.

Because not only blockage of nose can cause sleep apnoea or, make sleep apnoea worse. It can also affect your compliance with CPAP. So it is important for that to be sorted. And and then sometimes people just can't tolerate it. And then they fall into that group. Then you have to look at, an inferior second option, mandibular splint.

Dr Gavin Nimon: Yeah. Okay. Where do you think things are heading in the future then? What's the advances in the future for treatment of this condition? Is there smaller devices? Are there other options of assessment or treatment.

Dr Sanaz Lehman: I think there's a lot of research around newer treatments, but I don't think there is anything as [00:33:00] effective as CPAP. There are things like medications that they're saying, won't lead to the muscles collapsing, improves the tone of the muscles.

But at the end of the day, thus far, there is nothing as effective as CPAP. What is happening is the CPAP machines are becoming more and more sophisticated. And not only we have CPAP, which is just It's just continuous. positive pressure. You have things like BiPAP, which is bi level pressure, that the pressure is higher during inspiration, lower during expiration.

Or you have even more sophisticated machines such as ASV. And these machines are used more for people who have central apnoeas. They are tolerated better. So there are more and more sophisticated machines coming into the market. There are nicer masks, the machines now all have humidifiers, for example, that makes it easier, makes the air warmer and [00:34:00] humid.

So the machines are becoming more and more sophisticated. There are younger people that are going on CPAP, CPAP is becoming more and more part of people's lifestyles. So there is a lot of advances in CPAP, and there are advances in terms of medications or things that stimulate the muscles to increase the Diameter of the upper airways.

But thus far, CPAP is the main mode of therapy.

Dr Gavin Nimon: It's been brilliant hearing all about it and finding out more. Look, I really appreciate your time. Sanaz It's an excellent and obviously quite a complex area and something that I didn't get to see much of, obviously, but it's certainly something to be aware of.

Yeah.

Dr Sanaz Lehman: Exactly. And it is a very growing field. And really, since the late 80s, early 90s, it's been a growing field. So it's still a very young kind of a specialist area, but there has been a lot of advances and it's very common, it's important to screen patients for it and to treat patients.

Dr Gavin Nimon: Brilliant. Thank you very much [00:35:00] for coming on Aussie Med Ed and giving up your time. It's been great hearing about it and I really appreciate it. So thank you very much.

Dr Sanaz Lehman: Okay. Thank you. Thank you for having me.

Dr Gavin Nimon: Thank you.

. Well thanks for that Sanaz, I'm now going to introduce Professor Simon Carney, a professor of ENT based at Flinders University. He's authored 116 full publications, has 15 book chapters, has two surgical manuals, and with over 4, 000 citations, he has a H index of 38.

His current research is on phenotyping patients to predict benefit for multi level sleep surgery. He's current chair of the South Australian Society of Otolaryngology. Head and Neck Surgery.

​He's going to talk to us about surgical options for sleep apnoea. Welcome, Simon. Thank you very much for coming on board. It's a pleasure, Gavin. Well, it's great to have you here and to hear about different options. Sanaz has already outlined how important sleep is and what the issues are with sleep apnoea.

She's also outlined what the assessment is for working one up using sleep studies and talked about non operative measures. But I believe surgery is indicated on some occasions. When is [00:36:00] surgery indicated?

Professor Simon Carney: Well, there's lots of different surgical options. And the first thing I'd like to say is that children and adults are completely different.

So a lot of kids, uh, snore and get significant sleep disorder breathing. Um, and we're very aware of the impacts of sleep disorder breathing on kids, on their well being, their cognitive development, and their sort of speech and language skills as well. And it's usually due to adenotonsillar hyperplasia.

in kids almost invariably. There are exceptions. Kids with Down syndrome, for example, have got very big tongues, but usually it's the tonsils and the adenoids, and therefore taking the adenoids out and doing some form of surgery on the tonsils works brilliantly. An intracapsular tonsillectomy, where you remove about 95 to 99 percent of the tonsil and leave the capsule intact, is now essentially taken over as the mainstay.

Pediatric tonsil surgery in the absence of recurrent tonsillitis, whereas the, certainly [00:37:00] when you and I were young, that would take the whole tonsil, nothing but the tonsil, you know, that was the story, you know, you took it out, including the capsule, and it was incredibly sore for 7 to 10 days, and the bleeding rate was not zero.

Certainly the reoperative rate was about 2%, but the intracapsular tonsillectomy has made it much safer. So that's with kids. Now with adults, There are lots of options, and we've got to remember that airway is a tube, and it starts at the nostrils and at the lips. So, people who've got blocked noses, snore more, and by Operating on the nose will change the pattern of the airway resistance.

And as surgeons, we're obsessed with anatomy and actually improving the anatomy, but we've got to go back to our high school days and think about physics, and think about And that's sort of scratching my, uh, deep and distant memories. When we look at that, and there's a thing called a Starling [00:38:00] Resistor model, where if you think of your airways a series of resistors, and by improving the first resistor in the chain, you actually improve the, the chain.

Overall resistance of the whole airway. So, by clearing the nose, you actually will improve airflow through the palate and the tonsils and the, and the retrolingual segment. And so, by clearing the nose, you will alter the rest of the airway as well. Plus, the other thing that we work very closely with the respiratory physicians is by clearing the nose, you actually facilitate CPAP compliance.

And so, often, physicians like Sinaz will refer patients to me saying, look, this patient can't use the CPAP because her nose is blocked. We've got these great sports that the Aussies love, such as Australian rules and rugby and cricket, all three of which can have objects flying at your nose with great speed, causing septal deflections and fractured nasal bone.

And so, you know, I see a huge number of adults who've had sporting injuries with a blocked nose as a result of [00:39:00] that. So, by operating on the septum, And the turbinates, which are on the lateral wall of the triangle, you're actually going to improve the airflow. You might not cure sleep apnoea by clearing the nose, but what you also do through that styling resistor is you actually improve sleep fragmentation.

And for those of us who've got our smart watches, we're told about REM sleep, non REM deep sleep, and When you've got sleep apnoea or sleep disorder breathing, you flick between those different phases of sleep much quicker. And so with a clearer nose, you spend longer in each phase of sleep. And although your sleep apnoea may not be cured, by improving that sleep fragmentation, you're actually less tired.

And that's one of the major outcomes we always look for with patients with snoring and sleep apnoea is just how tired people are. Because as we know, that's the source of both morbidity and mortality. You know, people falling asleep at the wheel and having motor vehicle accidents and killing not only themselves but other [00:40:00] innocent bystanders.

So one of the big factors is people being less sleepy. By clearing the nose, the evidence is that significantly improves daytime fatigue. And then when the nose is clear, we always try and retry the devices because nasal surgery is relatively low risk. Once you start operating on the palate, the tonsils, and the tongue, we're increasing risk quite significantly, and not to mention post operative pain.

And that's the surgery that everyone talks about, the palatoplasty, the UPPP, uvulopalatopharyngoplasty, that really long word, um, UP3, UPPP, however you want to abbreviate it. And the techniques of that have changed over the years. So instead of being literally a diathermy and producing a gothic arch at the back of someone's throat, we're actually dividing the muscles, which Attach the palate to the pharynx and then suturing them forward.

So instead of it being a receptive procedure, it's a repositioning procedure. So we want those [00:41:00] guy ropes of the tent to be pulling the palate forwards and opening up the airway, both in an AP plane and a lateral plane. And then tongue reduction surgery likewise has been revolutionized by new technology as well.

So, this technology's really helped with sleep surgery, and then of course we've got the robot as well. The da Vinci's the main one, but there are smaller robots specifically for ENT now where you can operate over the top of the tongue, you know, trans aurally very easily, and that has meant we're able to do much more conservative operations on that retro lingual segment.

Dr Gavin Nimon: So those robotic surgeries that allow you to put further instruments to retract things out the way, how else does it help as well?

Professor Simon Carney: Well, the other thing is you're not operating on line of sight. So when you're operating on the back of the tongue through the mouth, you're sort of 70, 90 degrees around the corner.

And that's the thing with the robot is your eyes essentially go where the tip of the uvula is with the robot. So that's where you're viewing your surgery from and then able to use those. Robotic arms on either the back of the tongue or the epiglottis, [00:42:00] all of which have been transformed by the robot.

We're able to do those sort of surgeries where previously it was much more challenging.

Dr Gavin Nimon: As I understand it too, the vision you get with a robotic surgery is more stereotypic as opposed to when I'm doing a shoulder scope where you use triangulation to help.

Professor Simon Carney: Yeah, it's great. I mean, the 3D, the smaller robots don't have the 3D, but they've got haptics, which is another advantage.

Whereas the DaVinci, you lose the haptics, but you get the 3D. It, it literally is as if your eyes are at the back of the throat. It's very easy to operate on that posterior third of the tongue, able to resect the tissue and yet preserve the, the taste buds, which in South Australia is extremely important.

People like their red wine and you ruin that for them, they, they don't thank you. So we're able to do more on that segment, and of course, dysphagia and globus. big complications as well if you take too much. So it's important that we open the airway and some of the research we're doing at Flinders is currently trying to work out exactly where people are obstructing in a much more [00:43:00] accurate way before surgery.

So we can actually say to someone, well, actually a UP3 isn't going to work for you because that's not where the problem is. Your problem's at the epiglottis in the back of your tongue. And so trying to pick your winners is the most important thing.

Dr Gavin Nimon: And is there any assessment techniques to work out exactly where the most obstruction is?

Professor Simon Carney: There are lots of ways and even in the consulting room, when a patient awake, you can sort of get someone to simulate a snore and um, it's, it's often very helpful to have the partner there and say, is that what he or she sounds like? And say, no, he's far worse than that. And so you can actually sort of try and reproduce what's happening in the office.

There's a technique called the Woodson's Hypotonic Maneuver where you basically get the patient to exhale on a end of expiration when the lungs are empty. You keep getting the patient to push out, push out, push out. So you're forcing the patient to try and voluntarily collapse their airway and seeing where it would collapse when the patient's trying to.

Now it's obviously not perfect because it's not during sleep. And then the next option is the thing [00:44:00] called a DICE, Drug Induced Sedation Endoscopy. We're using propofol and midazolam in an operating theatre. You can then, again, put a fibre optic up the nose and see where they're snoring and see where they're collapsing.

And you can use this monitoring to measure the depth of anaesthesia. But again, it's a simulated sleep. And so, some of the research we're doing at the moment, and we've got a grant from the Passon Williams Foundation to, um, Try and use artificial intelligence in the home with smart mattresses and sensors to not only record acoustically over a multi night period, but also to measure airflow patterns, obstructive patterns, and the old traditional flow volume loop, which we learned in physiology, you know, to see the shape of that curve and epiglottic collapse in particular, just shows a sudden change.

cessation of airflow on that flow volume loop, so you get a complete vertical curve as that epiglottis literally slams shut like a truck door. It's probably one of the biggest reasons for failure of sleep [00:45:00] surgery is missing that epiglottic collapse, because you can get the palate as good as you want, you can get the tongue as good as you want, but if you've got epiglottic collapse, you're still going to obstruct, and you're putting a patient through an extremely painful operation for zero benefit.

And so by putting By picking those patients before you embark on the journey, you're going to get much better results and also much happier patients. So I think in the next few years, we'll be using home based technologies to predict cytocollapse. And then the other thing is that with high quality acoustic recordings in the home to actually measure sound, we can then Try and reproduce that exact same sound in the, in the DICE environment in the operating theater and just make sure we are actually getting the same pattern of airway collapse so we can actually then work how, how as surgeons we can improve the airway.

Dr Gavin Nimon: So AI would be used to analyse huge amounts of data.

Professor Simon Carney: So these smart mattresses have got up to 50 channels of data. And if you're analysing 50 data channels on multiple nights, you know, you need AI to help sort the sheep out from the goats. And you've got to [00:46:00] sift through all that amount of data. And then the other thing as surgeons, which is TGA approved but not.

Medicare approved yet is upper airway stimulation. So like pacemakers for the airway. And in the States and in Europe, they've been stimulating the hypoglossal nerve, and you get a like a pacemaker which sits over the hypoglossal nerve, which stimulates the trunk protrusions when a apnoea is detected. And there's now 41, 000 of these devices being implanted, you know, worldwide.

They're about 35, 000 and we're optimistic that the I think in the next few years, it will be approved in Australia and be available with patients health funds. But again, it's not suitable for everyone. So this is, again, as surgeons and trying to do this pre surgical workup to work out who's going to benefit from nasal surgery, who's going to benefit from pharyngeal tongue surgery, and who's going to benefit from upper airway stimulation.

Because there are different phenotypes and different cohorts of patients that will be better suited for [00:47:00] each individual option.

Dr Gavin Nimon: How do you differentiate of the huge cohort of patients with sleep apnoea, which ones need to see an ENT surgeon to ascertain whether they can benefit? You wouldn't be able to cope with the huge numbers of people coming through, all appearing at ENT surgeons for consideration of surgery.

There must be sums that help determine which ones are better and which ones are worse prognosis?

Professor Simon Carney: Yeah, so I think that The education, both at the primary care level and the physician level, is really important. You don't need a lot of BNT skills to just have a look in the mouth, assess the position of the tongue, there's a modified malampathy score as to where the tongue sits in relation to the uvula and the palate, and assessing the tonsil size, you know, grade 1, If you've got massive gobstopper grade 4 tonsils, you know, you've got eminently fixable airway collapse.

It's great working in multi disciplinary environments, I find, incredibly worthwhile and very positive. And to work as part of a team that overall assesses a patient, it's what makes it all [00:48:00] worthwhile. So if, you know, you get a phone call from a sleep physician saying, I've got this patient, you know, they really can't tolerate the sleep apnoea, they've got, you know, big tonsils, I think they're ideal for you.

And it's a two way street as well. I see patients primarily, you know, I don't think surgery is for you. I think you need to go off and see a sleep physician. I think you probably need CPAP or a Mandibular Advancement Splint. Or a positional device or weight loss, which is the other big thing. And that's the other thing is that if you're operating on people with a BMI more than 38, you're going to fail.

Ideally, they want to be under 35 BMI, that's increasingly challenging. But with drugs like Azempic available, you know, that is changing. There are options now to get these patients below 35 quite easily. And then bariatric surgery, so often we're sending patients off for bariatric surgery and then often they get cured.

Uh, the sleep apnoea just fixes itself because something I was never taught in medical school is that the tongue contains a fat pad. So deep within the [00:49:00] intrinsic muscles of the tongue is the intraglossal fat pad. You put on weight, that fat pad increases in size so that the cushion in the box gets bigger.

The box doesn't change in size, but the tongue grows and grows. And likewise, when you lose weight, that tongue reduces in size and that retro lingual collapse just vanishes.

Dr Gavin Nimon: What investigations would you do apart from a good examination and assessing them? Are there any other things, CT scans or MRI scans that are done as a workup prior to you seeing them?

Professor Simon Carney: If the patient's got a nasal problem, we, you know, we'll do a naso endoscopy, assess the septum, and any sinus issues, we'll get a sinus CT. Sleep surgeons routinely perform lateral skull cathelometry, looking at the angles of the skull base, but upper airway CT, it probably only has a role if you see something odd on examination.

Obviously, you know, if you find a massive lingual thyroid or something like that, you'd want to get the CT or anything that was suspicious, maybe tongue based lymphoma. Um, but the other things are just quality of life scores. Upward sleepiness score, just to ascertain how sleepy the patient is. We use a stop [00:50:00] bang score, which looks at all the risk factors for sleep apnoea.

And a snoring severity score from the partner is always helpful as well. And a good quality sleep study, um, I'm sure Sanaz has spoken about that. And that's it. Of course, the sleep study as well has massive amounts of data and has to be reported properly. We do have to remember that, uh, upper airway surgery is not without risk, um, and fully informed consent means we have to warn the patients of all the risks that are associated with it, um, including the very rare chance of fatality, which is important for us to outline to the patient because, of course, CPAP might be inconvenient for people, but it's an extremely low risk alternative to surgery.

Dr Gavin Nimon: So, depending on the area you're operating from, what's the sort of failure rate or success rate of these procedures?

Professor Simon Carney: Well, the big thing is how do you define success? If you actually look at patients and say, well, would you go through the surgery again, which is probably the most important thing, it's about 85 90%.

So, and the role of [00:51:00] surgery is not always to cure the patient, because that's often unrealistic. But if you can get someone from an AHI of 60 down to 20, You know, you've essentially reduced their cardiovascular risk. You're going to make them much less tired. And okay, they may not have a normal AHI, but they're essentially cured.

And there are various criteria of assessing improvement. Um, and we did a randomized controlled trial based at Flinders, which was published in JAMA. Took 10 years off my life, that trial, but it essentially showed that on average, the mean improvement in AHI was 20. So, we started off with a cohort with a mean of around 39 and we were finishing at about 19.

So, you're significantly improving people's AHI and their ESS, their Epidural Sleepiness Score, again significantly improved. So, we've normalized people's sleepiness. Whereas, to actually, in inverted commas, cure, close inverted commas them, and get them with an AHI less than 50 percent and under 20, was [00:52:00] about 56%.

of absolutely cured patients. But then, like we said, 85 to 90 percent were significantly better and said they would go through the procedure again.

Dr Gavin Nimon: Obviously there's a fair bit of research you're doing at the moment. Where do you see this area progressing over the years to come?

Professor Simon Carney: I think the identification of the different patient phenotypes.

As surgeons, you know, we're incredibly simple individuals and we just look at anatomy and try and make it bigger. When in fact that's an oversimplification. You know, people who've got poor central respiratory control, you know, they're not driving the airway dilators enough, you know, are a group that, you know, is incredibly important to identify.

And so technology to identify who's just got that poor central muscular control and who, for example, has got a floppy tongue. You know, you can have a normal sized tongue, which is just floppy and just flops back. These upper airway stimulation techniques, both the hyperglossal and, of course, the new kid on the block is antiservic aortic stimulation.

So trying to get An electrode onto the, an [00:53:00] cervicals and the strap muscles, the neck is a lot easier than going high up around the hyoid, uh, onto the hypoglossal nerve. So, and by the, an cervical stimulation, uh, just drops the hyoid so it SubT tenses the airway, so it's tensing the tube so it doesn't collapse, rather than moving the tongue forward, which is what the hypoglossal nerve stimulation does, and increasingly new medications.

So there are, there's also the Adelaide Institute of Sleep Health doing a lot of research on just medications which will improve airway tone at night, which will stop collapse, um, positional devices and other things to just keep the airway open. Um, I think we'll be the way of the future. So I think in 10 years time we'll be doing much less aggressive surgery, would be my prediction.

I think the, the days of everyone getting a, a painful palatoplasty I think will be long gone.

Dr Gavin Nimon: Right. It was obviously great to hear what the options are. Just to go through those stimulators, are they just implantable electrodes that are put under the skin and then placed up against the [00:54:00] nerves?

Professor Simon Carney: There's now three different generations of devices.

So the first generation were cuffs that went around the hypoglossal nerve and you tried to place it as distal as possible so you're getting the airway protruders rather than the ones that retract the tongue. And they contained, you know, up to four, you know, Electrodes, uh, which could be selectively stimulated, depending on which ones work best.

And the earlier ones had a, um, a center in the intercostal muscles to detect apnoeas. Second generation devices are bilateral, and they sit bilaterally over the, uh, genia glossus under the chin, like a, uh, a double paddle. So one paddle over the left and one paddle over the right.

Dr Gavin Nimon: Right.

Professor Simon Carney: And then there's a percutaneous sort of magnetic instrument that you just literally just put under your chin at night and that uses an algorithm based on your sleep patterns from the night before to calculate when you're going to be obstructing and when to stimulate the, the hypoglossal nerves [00:55:00] bilaterally.

And then the third generations of implants are Are gonna be, uh, placed under ultrasound. So percutaneous, so under ultrasound control, it's sort of inserted percutaneously right next to the, uh, either the hypoglossal nerve or the an CLIs. And they're gonna have much more electrodes because obviously the, the accuracy of, of placement is less than under direct surgical vision.

Um, and therefore you, you need multiple electrodes to make sure you're getting the sweet spot.

Dr Gavin Nimon: How big are the nerves around the tongue we're talking about? What's the sort of size? Are they a few millimetres in size or are they bigger than that?

Professor Simon Carney: I mean the hypoglossal nerve is about millimetres at the hyoid.

And then as the different branches get given off, it goes down to 2 to 3 millimetres at the site of implantation. And then the, the, I think the more modern devices, you know, it's, it's not always necessary that you're simulating the nerve, you know, to simulate the muscle itself probably works as well. So, as long as you're getting the airway opening, it doesn't really matter whether you're simulating the nerve directly or [00:56:00] whether you're stimulating the muscle.

Both will work. And that's the same with the anti cervicalis. You know, if you're putting the electrodes between the strap muscles, between the sternohyoid and the sternothyroid, you know, you're getting in that plane, you're probably stimulating both of those muscles.

Dr Gavin Nimon: Look, it's been brilliant hearing about different options.

Do you think the take home message is? Well, I

Professor Simon Carney: think the first thing that can be done at a very primary care level is to assess the nose and to look in the throat. And I think by doing both of those, you will pick people with very easily fixable pathology very early. And I think they're the ones where they're in a referral to an ENT surgeon to fix the problem.

Or even if someone's got such a blocked nose that they're never ever going to be able to tolerate CPAP. There's little point in getting that fixation in the first place, because the patients will A, not use it, and then be very worried about it. Resistant to other options because, oh, it didn't work. And sort of bringing the patient along on the journey.

And multidisciplinary care, I think, is the way forward. And I think we're very lucky in Adelaide in that we do have a [00:57:00] very good multidisciplinary team. A lot of people, you know, work very closely together. And, you know, that shared care model works really well.

Dr Gavin Nimon: Brilliant. Well, look, thank you very much for your time.

It's Professor Simon Carney. Thank you very much for coming on Aussie Med Ed.

Professor Simon Carney: Thanks again, Gavin. Thanks a

Dr Gavin Nimon: lot.

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