UARS: A Critical Link to Optimizing PAP Therapy Results

I read through some other posts on UARS, and frankly, I'm disturbed by a number of comments from individuals who may be inadvertently providing misinformation to this forum.

Having trained with the pioneer researcher Dr. Christian Guilleminault who discovered UARS, I wish to make a few comments that might help PAP therapy users optimize their responses to find high quality sleep.

A reminder that for all practical purposes, the following three terms are interchangeable:

· UARS (upper airway resistance)
· Flow limitation
· RERAs (respiratory effort-related arousals)

UARS as Mini-Suffocations

First and foremost, let's look at an analogy in cardiology to put to rest the nonsense that UARS does not exist or is somehow not important. We all know that asystole (heart stops) is bad, just as we know apnea (breathing stops) is bad. But, in cardiology, for decades we've known there are many other cardiac arrhythmias producing irregular heart rhythms, and we don't sit back and say, "well it's not asystole, so it must be OK." For decades, unfortunately, that practice is in fact what many physicians were taught or conditioned to believe, "it's not apnea, so it must be OK." Indeed, to this very day, I still see patients who have been to sleep doctors who told them their sleep study was OK because it didn't show apneas.

But, as we like to say, “a little choking is still choking,” therefore I think it is reasonable to state that each of the various forms of sleep-disordered breathing (apneas, hypopneas, UARS) reflects some degree of “suffocation.” Apnea is the most concrete form as the patient awakens choking or gasping, whereas UARS is probably equivalent to a “mini-suffocation,” which while asleep I imagine produces an unpleasant sensation but not choking.

UARS is not Mutually Exclusive of Hypopneas or Apneas

Please appreciate then that UARS is simply on the continuum of breathing events. To complete our analogy, UARS represents a more subtle form of breathing irregularity (or as some say pulmonary dysrhythmia). It is not mutually exclusive of apneas or hypopneas. You can have all three types of events when you are diagnosed with sleep-disordered breathing (SDB). In fact, the most common type of SDB shows all 3 components in varying proportions during the sleep study.

You would think though that apneas are more important than UARS events, right? Well, maybe. Don’t forget that UARS events, like apneas, are also frequently associated with sleep fragmentation and therefore unequivocally associated with daytime sleepiness and fatigue. We have seen patients with severe UARS (e.g. RDI > 40), who unequivocally have more sleepiness than say a patient with a moderate degree of apneas and hypopneas (AHI =20). That is why RDI (apneas + hypopneas + UARS) is more valuable when diagnosing and treating your condition than AHI.

To repeat, it is critical to realize that nearly all patients with OSA also have a UARS component on their diagnostic sleep studies, but if the sleep lab doesn’t use the proper respiratory sensors, they will not see it: "what you don't look for, you will not see!"

UARS Assessment and Treatment is Critical to Titration Success

Still more importantly, when a titration is conducted, UARS is invariably present, because the pressurized airflow doesn’t work like a magic wand to suddenly make apneas disappear. Apneas are often turned into hypopneas as the pressure is increased. Then hypopneas turn into UARS or as more commonly called in the lab nowadays “flow limitation.” Remarkably, many sleep lab techs do not push forward with the titration at this point, believing that their job is done. Even some proportion of sleep medicine physicians do not mandate that their sleep techs increase pressure for flow limitation.

“Consensus Medicine” Covered up The Science of UARS

How anyone would think UARS doesn't exist or isn't important probably relates to the sometimes misguided concepts of "conventional wisdom" and "consensus medicine" and how such processes frequently retard scientific discoveries from finding their way into community medical practices. In the early 1980s, papers were published about sleep apnea, then Medicare got on board to accept and cover the condition, after which a new CW was born that's taken quite awhile to revisit.

Once physicians and patients became accustomed to hearing the words "sleep apnea," it was only natural that people would block out any other pictures about the nature of a sleep breathing disorder. A consensus formed: either you stop breathing or you don't! Black and white, eliminate the gray! Which is why we always return to the heart rhythm analogy to help people understand the need to monitor different breathing irregularities, not just apneas.

I have treated thousands of patients with UARS who had either no apneas or hypopneas or an AHI less than 5. Nearly all these patients suffered sleepiness or fatigue from their conditions, and many suffered from insomnia and nocturia. Among those who were able to successfully use an appropriate SDB treatment (e.g PAP therapy, oral appliances, nasal strips, nasal surgery, nasal hygiene and so on.), virtually all achieved clear-cut improvements in their symptoms.

What’s in a Name?

In most of my UARS cases, the patients would almost invariably start the discussion with, “so, you don’t mean I have sleep apnea do you?” Which is interesting, because if you follow the workings of the American Academy of Sleep Medicine, you’ll notice their strategy is to abandon the word UARS, and simply declare that UARS equals sleep apnea. In their lexicon, they would answer the UARS patient as follows, “yes, you have sleep apnea, oh but by the way, you don’t stop breathing.” See the problem? That’s why I continue to use the term UARS to make it clearer to the patient.

As an aside, I’ve seen cases where the UARS was ridiculously subtle (I was almost too embarrassed to call it UARS) or it only appeared in REM sleep. I had to inform these patients that I was skeptical about whether PAP therapy would make any difference. Although I still encouraged this particular subset of patients to give PAP therapy a chance, no more than 50% were willing to try it. Yet, in several cases, some of these patients reported dramatic and sustained (as in years) improvements in fatigue or sleepiness with PAP therapy. Undoubtedly, we find these events very perplexing, but the upshot appears to be that sleep assessment technology for measuring respiration and arousals has a long way to go….but then most of you knew that already!

Start Connecting Some Zzzzzots

Along these lines, let me mention a working theory we have developed about UARS and why bilevel might be the best option for its treatment.

The most salient factor during most titrations is how well the patient responds during expiration. Think about it: it sure feels a lot easier if not pleasurable to breathe in with pressurized airflow coming into your lungs. Many SDB patients are immediately hooked on PAP therapy because of this singular experience.

But breathing out against pressurized airflow is a completely different experience for a very large proportion of patients. After all, it’s downright weird to breathe out when pressurized air is coming in. And, that’s exactly how many people describe it and worse. It’s weird, anxiety-producing, claustrophobic, and triggers a sense of panic. Now, the biggest question is who are the types of UARS patients that would feel so negatively about exhaling on PAP therapy?

In our clinical and research experience, it would be someone who already has some degree of anxiety, a lot or a little, it may not matter, because once they try to use fixed CPAP in particular, they quickly report that it’s very uncomfortable or worse, they report feeling more anxious.

In a large proportion of these patients, we switch them to bilevel during the pre-sleep desensitization/adaptation period, and remarkably, we have found that 90% of these patients report immediate relief by virtue of the lower expiratory pressure.

Note: Bilevel combines IPAP (pressure on Inhalation) and EPAP (pressure dropping on Exhalation).

Can You Feel Anxiety in your Sleep?

Although we have more recently discovered that most patients want to switch to bilevel during the desensitization, that is, before the formal titration begins, we didn’t really figure out this point until we watched UARS patients while asleep. That’s when we saw that they did not like CPAP, that is, a fixed pressure on exhalation. That’s when we saw the ratty looking signal suggesting they were having some kind of anxiety or otherwise unpleasant response to air coming in while they were trying to breathe out.

In my opinion, which I don’t think is shared by the majority of sleep docs, anxiety is experienced while you sleep. If you can experience anxiety in dreams, I don’t see why you can’t experience anxiety to pressurized airflow in your sleep. So, in a nutshell, I think that’s why CPAP doesn’t work well in UARS patients and for that matter, I don’t think it works well in most SDB patients except for truly classic hypersomnolent, anxiety-free, sleep apnea cases.

I think anxiety is already present in the majority of SDB cases, because it is an anxiety-producing experience to breath abnormally all night long. That is, anxiety and breathing are intimately connected, so most SDB patients are more or less conditioned to be more nervous in general by having spent the night not breathing well. Now, introduce a foreign stimulus, CPAP, which then triggers or worsens anxiety by the introduction of an extremely foreign sensation: pressurized airflow forced inward during exhalation.

Is Bilevel the Answer?

Why bilevel works so well is still a puzzle. But, what’s so intriguing is that the subjective and objective findings match. That is, nearly all patients who switch from CPAP to bilevel state that it is easier (subjectively) to breathe out with bilevel. And, during their titrations, the ratty airflow signal disappears on expiration (objectively) and is replaced by a smooth and rounded curve indicating normal expiration.

Should you be able to produce the same results with CFLEX, APAP, etc? Presumably so, except for one “large” difference. You cannot generate the same gradient or gap between IPAP and EPAP with any of the other devices. And, in our clinical and research experience, we are using gaps of 4 to 12 cm of water in our patients. My personal bilevel settings are 21/12.5 for a gap of 8.5.

In our prescriptions for bilevel, I would venture that the average gap is in the 5 to 6 range with tremendous variation, including some with a gap of only 2 or 3. Those with a lower gap requirement would likely do as well on FLEX or APAP, but to repeat, the large majority of our patients have a gap of 4 or greater.

Still, it would be nice to have a respiratory physiologist explain to us why the larger gap is so effective. As an internist and sleep medicine physician, there are only two obvious theories that stand out. First, what if we’ve always assumed, mistakenly, that airway pressure had to be constant for both inspiration and expiration? I think it has already been proven by other researchers that you actually need higher pressure to keep the airway pinned open on inspiration and a lower pressure on expiration. If that’s so, then is bilevel the best system because it provides the exact pressure you need (not too much and not too little) during expiration.

The second idea relates more to the psychophysiological response to PAP therapy. Maybe the larger gradient simply gives the patient a distinctly more comfortable feeling, because the lower pressure creates a feeling so much closer to breathing normally (without PAP). If this theory were accurate, though, it would imply that over time as you get used to any sort of PAP therapy, then perhaps the gap would narrow and eventually you could use fixed CPAP again. If this were true, I would expect more people to eventually adapt to fixed CPAP pressure, and I don’t believe that’s occurring.

UARS Diagnosis and Medicare

Last, insurance coverage for UARS is always a hot topic. This section is not relevant to titrations, because nearly everyone manifests UARS on the titration. Insurance questions revolve around the diagnostic study: does the patient “only” have UARS?

In Albuquerque, I have pushed back on this issue for more than a decade, and the results have been tangible and somewhat satisfying. At this point, there are only 3 insurance carriers in New Mexico who do not cover treatment (specifically, PAP therapy or oral appliances) for UARS. Even among these 3 carriers, we can always make an appeal on very specific comorbidities (e.g. a UARS patient who has had 2 car accidents in the last year), then Medicare might decide to cover such a UARS patient.

In the beginning of this particular journey, I found it frustrating at first, but it was also an opportunity to educate medical directors at insurance companies. We would routinely call these individuals, send them research publications, and explain how UARS was going to cost them more money in the long-run if they didn't cover it.

As an aside, I have to mention how frustrating and disappointing it is to hear about sleep physicians who might make their decisions about UARS based on insurance considerations. I was never trained to think that way in medical school, and it approaches unethical behavior in my opinion. If a patient is diagnosed with UARS, that's the diagnosis whether it's covered by insurance or not. Insurance companies don't tell me what I can diagnose and they don't tell me how to treat my patients!

Financial considerations are relevant and important, but they have nothing to do with my patient advocacy and my duty to inform the sleep patient of the diagnosis and treatment plan we recommend.

I am deeply perplexed by the notion that a sleep physician would withhold this information from a UARS patient because the insurance company wasn't going to cover it. As before, it borders on unethical behavior, in my opinion.

Summing Up

Last and not least, UARS is one of the primary reasons that many SDB patients do not achieve an optimal response. As I describe at length in my book, it is a human tendency to "normalize" behaviors, which over time prevents us from obtaining the best possible response to PAP Therapy. If you are so used to fatigue and sleepiness, having suffered for so many years, then how could you possibly discern what a normal level of sleepiness and fatigue should be? Instead, (and I know this from my own trials from CPAP to APAP and finally bilevel), when you experience some improvement, the tendency is to create a new "normal" and wrongly assume that this is "as good as it gets."

Well, it's not as good as it gets if the UARS component of the SDB hasn't been treated, because there is still more to treat. Undoubtedly, most of the members of this forum recognize the fine-tuning and tweaking that's needed to manage mask leaks, mask comfort, mouth breathing, humidifier settings, and nasal congestion, just to name a few of the issues that must be regularly attended to enhance the PAP response.

Notwithstanding, in my clinical experience, I have found that resolving the UARS component of SDB is in the top tier of factors that frequently must be addressed to achieve optimal results, especially so among patients whose regular use of PAP therapy has not yielded the desired effects.

I've lived through this problem and I've breathed through it, and no other single factor enhanced my sleep quality to the level I currently enjoy and am eternally grateful for experiencing.

Surely, this is something to sleep on. I do, night after night.

P.S. Sorry for the long post; but it's not my fault, it's the bilevel. After 7 near perfect hours of sleep quality last night, I had to do something to burn up the energy.

My UARS was covered after an appeal to my insurance company by my doctor. I had, at that time, very good insurance coverage, which I'm sure contributed to the final approval.

When I changed to an HMO, they approved all supplies, etc. by a letter of medical necessity from my doctor.

He had sent me home with a 5 night trial with a loaner cpap and downloaded the data. I had never slept so well in my life!, My doctor was so frustrated at the insurance company, that the day after my machine was delivered, his nurse called to tell me that he had an extra machine which he was willing to give me to begin my treatment.

I have been 100% compliant since October 2005. Since cpap therapy, I have not woken up once feeling like I was smothering or choking.

Thanks for the long post, Barry.

Up to this sentence

If this were true, I would expect more people to eventually adapt to fixed CPAP pressure, and I don’t believe that’s occurring.

It describes me to a T.

I'm not sure about that last sentence though, at least as far as the people with relatively lower pressures are concerned.

I think that under certain conditions, people do get used to fixed pressures, but the reason you aren't finding those people or conditions that it has never been checked systematically.

People are sent out of labs with their "correct" cpap pressure - and left to flounder. I have yet to hear of a person who was told by the doctor (or lab) OK, this is the pressure you need, but we'll start building up to it gradually.
What I sometimes call the "tracheotomy model" seems to reign supreme: "we titrate you one night, and then we know what's right for you, and we expect you to use it and adapt to it".

However, breathing out against pressure demands we do some muscular work we're not used to - an effort that signals "you're choking, there's a problem" to some of us. Physically, some of us even experience sore muscles when we start breathing against pressure we're no used to.

On the other hand, sooner or later (I'm a "much later' case, at relatively low pressures) we do get used to this weird experience. Eventually the pressure no longer signals "danger" and,we are no loger even sure if there's air blowing in - we have to put our hand in front of the mask for that. For me, the desensitization occured becuase I have an automatic machine, and its top range was limited to a pressure that didn't terrify me.

What I'm trying to say is this: for a person to get used to fixed pressure, they have to have a certain level of comfort (or limited discomfort) when breathing out. If their prescribed pressure causes too much anxiety, they won't adapt to it, since anxiety will keep them from sleeping. Ramp was no solution for me because fear of the moment the pressure would be too high kept me waiting for it (like wating for the second shoe to drop). But, if people are given a training period at suboptimal pressures, and then the pressure is raised gradually, I think they might. (I'm not saying this is better than bi-level - not at all).

Of course, I dont' think this is true at any pressure, and even I - from the height of a "top range at 8" but with tons of flow limitations (according the the 420E) am very tempted to experience bi-level treatment....

O.

Dr Krakow,

Thank you for taking the time to share with us that very informative post! In my experience both with my own multiple chronic medical conditions and working in medical research, I've noticed that typically more docs who live with the same or similar condition (depending on their circumstances) are likely to understand what the patient goes through and, as you noted, are more willing to understand that just because standard medical definitions say one thing, it is possible for the real situation to be more complex. In It's not really surprising that a doc who has never experienced anything like what the patient has is unlikely to truly understand how the patient is feeling.

I was diagnosed with "mild" sleep apnea and my sleep doc and the tech went to extra mile to do an additional tedious analysis of my sleep study data so that my insurance company would cover the equipment. Although mine is "mild", I'm finding that this therapy is helping me a great deal - more than I ever expected. I was using APAP, but recently switched to CPAP with C-FLEX and I'm finding that more comfortable than the constantly varying pressures. I've never experienced CPAP without the expiratory relief.

I hope that you will keep posting. It's easy for misconceptions to get started and all of us can inadvertently pass them along and, like the telephone game, info can so easily become more and more distorted.

It's especially helpful since we know that you have similar experiences to what we have *and* you have the medical knowledge.

Mindy

Thanks for the long post. Well written, I found your views of UARS very understandable and the relationship to anxiety very logical.

However, as ozij noted, perhaps some of us do adapt to the pressure and anxiety diminishes over sufficient time. In addition, for those of us with very severe OSA, adaptation to pressure may be even more enhanced due to our immediate response to improved O2 levels and anxiety may not even register as an SDB issue. As you pointed out, normal breathing is a very relative phenomenon.

For myself (w/ Dx AHI of 102 and AI of 99 and 60% O2 desats), I noticed immediate change with PAP treatment. I tweaked my treatment to an optimal AHI < 0.5 with fairly consistent AI of zero. Nonetheless, on occasion I do still have a mild bout of daytime sleepiness. Maybe UARS has finally become more relevant to me now that my body has fully readjusted to normal O2 levels? However, without another sleep study, I have no idea if indeed I am experiencing UARS or not (I guess the P&B 420E is the only machine that records FLs?). I don't consider myself to be prone to anxiety (at least not while awake).

I have two APAP machines ... one with CFLEX and one with the newer AFLEX technology. Although I have tried each of them for a night or two, I have not felt the need to use expiratory relief and hence have not really used these features. Your views have compelled me to try these exhalation relief features for a longer trial period to see if I can observe any significant differences in the quality of my sleep.

Anyhow, very interesting ... thanks again for your efforts.

DreamStalker wrote: However, without another sleep study, I have no idea if indeed I am experiencing UARS or not (I guess the P&B 420E is the only machine that records FLs?). I don't consider myself to be prone to anxiety (at least not while awake).

DreamStalker, if you've got the M-Series A-Flex, that will record FLs if you're in APAP mode. Since I just switched to CPAP mode, I've found that they are no longer recorded. I have no idea what are "good" numbers of FLs.....

Mindy

mindy wrote:

DreamStalker wrote: However, without another sleep study, I have no idea if indeed I am experiencing UARS or not (I guess the P&B 420E is the only machine that records FLs?). I don't consider myself to be prone to anxiety (at least not while awake).

DreamStalker, if you've got the M-Series A-Flex, that will record FLs if you're in APAP mode. Since I just switched to CPAP mode, I've found that they are no longer recorded. I have no idea what are "good" numbers of FLs.....

Mindy

Thanks, I'll get my AFLEX machine back out of the box tonight and check it out.

mindy wrote:

DreamStalker wrote: However, without another sleep study, I have no idea if indeed I am experiencing UARS or not (I guess the P&B 420E is the only machine that records FLs?). I don't consider myself to be prone to anxiety (at least not while awake).

DreamStalker, if you've got the M-Series A-Flex, that will record FLs if you're in APAP mode. Since I just switched to CPAP mode, I've found that they are no longer recorded. I have no idea what are "good" numbers of FLs.....

Mindy

Like everything else, Mindy......"ZEROS".

Den (still tryin' to figger out what we're supposed to do with all of this "information" on FLs and UARS)

[quote="DreamStalker"][quote="mindy"][quote="DreamStalker"]
Thanks, I'll get my AFLEX machine back out of the box tonight and check it out.

oops - slippy fingers!

Ooooh - 10 lashes with a net noodle for you, Den

Mindy

BarryKrakowMD wrote:I read through some other posts on UARS, and frankly, I'm disturbed by a number of comments from individuals who may be inadvertently providing misinformation to this forum.

Having trained with the pioneer researcher Dr. Christian Guilleminault who discovered UARS, I wish to make a few comments that might help PAP therapy users optimize their responses to find high quality sleep.

A reminder that for all practical purposes, the following three terms are interchangeable:

· UARS (upper airway resistance)
· Flow limitation
· RERAs (respiratory effort-related arousals)

UARS as Mini-Suffocations

First and foremost, let's look at an analogy in cardiology to put to rest the nonsense that UARS does not exist or is somehow not important. We all know that asystole (heart stops) is bad, just as we know apnea (breathing stops) is bad. But, in cardiology, for decades we've known there are many other cardiac arrhythmias producing irregular heart rhythms, and we don't sit back and say, "well it's not asystole, so it must be OK." For decades, unfortunately, that practice is in fact what many physicians were taught or conditioned to believe, "it's not apnea, so it must be OK." Indeed, to this very day, I still see patients who have been to sleep doctors who told them their sleep study was OK because it didn't show apneas.

But, as we like to say, “a little choking is still choking,” therefore I think it is reasonable to state that each of the various forms of sleep-disordered breathing (apneas, hypopneas, UARS) reflects some degree of “suffocation.” Apnea is the most concrete form as the patient awakens choking or gasping, whereas UARS is probably equivalent to a “mini-suffocation,” which while asleep I imagine produces an unpleasant sensation but not choking.

UARS is not Mutually Exclusive of Hypopneas or Apneas

Please appreciate then that UARS is simply on the continuum of breathing events. To complete our analogy, UARS represents a more subtle form of breathing irregularity (or as some say pulmonary dysrhythmia). It is not mutually exclusive of apneas or hypopneas. You can have all three types of events when you are diagnosed with sleep-disordered breathing (SDB). In fact, the most common type of SDB shows all 3 components in varying proportions during the sleep study.

You would think though that apneas are more important than UARS events, right? Well, maybe. Don’t forget that UARS events, like apneas, are also frequently associated with sleep fragmentation and therefore unequivocally associated with daytime sleepiness and fatigue. We have seen patients with severe UARS (e.g. RDI > 40), who unequivocally have more sleepiness than say a patient with a moderate degree of apneas and hypopneas (AHI =20). That is why RDI (apneas + hypopneas + UARS) is more valuable when diagnosing and treating your condition than AHI.

To repeat, it is critical to realize that nearly all patients with OSA also have a UARS component on their diagnostic sleep studies, but if the sleep lab doesn’t use the proper respiratory sensors, they will not see it: "what you don't look for, you will not see!"

UARS Assessment and Treatment is Critical to Titration Success

Still more importantly, when a titration is conducted, UARS is invariably present, because the pressurized airflow doesn’t work like a magic wand to suddenly make apneas disappear. Apneas are often turned into hypopneas as the pressure is increased. Then hypopneas turn into UARS or as more commonly called in the lab nowadays “flow limitation.” Remarkably, many sleep lab techs do not push forward with the titration at this point, believing that their job is done. Even some proportion of sleep medicine physicians do not mandate that their sleep techs increase pressure for flow limitation.

“Consensus Medicine” Covered up The Science of UARS

How anyone would think UARS doesn't exist or isn't important probably relates to the sometimes misguided concepts of "conventional wisdom" and "consensus medicine" and how such processes frequently retard scientific discoveries from finding their way into community medical practices. In the early 1980s, papers were published about sleep apnea, then Medicare got on board to accept and cover the condition, after which a new CW was born that's taken quite awhile to revisit.

Once physicians and patients became accustomed to hearing the words "sleep apnea," it was only natural that people would block out any other pictures about the nature of a sleep breathing disorder. A consensus formed: either you stop breathing or you don't! Black and white, eliminate the gray! Which is why we always return to the heart rhythm analogy to help people understand the need to monitor different breathing irregularities, not just apneas.

I have treated thousands of patients with UARS who had either no apneas or hypopneas or an AHI less than 5. Nearly all these patients suffered sleepiness or fatigue from their conditions, and many suffered from insomnia and nocturia. Among those who were able to successfully use an appropriate SDB treatment (e.g PAP therapy, oral appliances, nasal strips, nasal surgery, nasal hygiene and so on.), virtually all achieved clear-cut improvements in their symptoms.

What’s in a Name?

In most of my UARS cases, the patients would almost invariably start the discussion with, “so, you don’t mean I have sleep apnea do you?” Which is interesting, because if you follow the workings of the American Academy of Sleep Medicine, you’ll notice their strategy is to abandon the word UARS, and simply declare that UARS equals sleep apnea. In their lexicon, they would answer the UARS patient as follows, “yes, you have sleep apnea, oh but by the way, you don’t stop breathing.” See the problem? That’s why I continue to use the term UARS to make it clearer to the patient.

As an aside, I’ve seen cases where the UARS was ridiculously subtle (I was almost too embarrassed to call it UARS) or it only appeared in REM sleep. I had to inform these patients that I was skeptical about whether PAP therapy would make any difference. Although I still encouraged this particular subset of patients to give PAP therapy a chance, no more than 50% were willing to try it. Yet, in several cases, some of these patients reported dramatic and sustained (as in years) improvements in fatigue or sleepiness with PAP therapy. Undoubtedly, we find these events very perplexing, but the upshot appears to be that sleep assessment technology for measuring respiration and arousals has a long way to go….but then most of you knew that already!

Start Connecting Some Zzzzzots

Along these lines, let me mention a working theory we have developed about UARS and why bilevel might be the best option for its treatment.

The most salient factor during most titrations is how well the patient responds during expiration. Think about it: it sure feels a lot easier if not pleasurable to breathe in with pressurized airflow coming into your lungs. Many SDB patients are immediately hooked on PAP therapy because of this singular experience.

But breathing out against pressurized airflow is a completely different experience for a very large proportion of patients. After all, it’s downright weird to breathe out when pressurized air is coming in. And, that’s exactly how many people describe it and worse. It’s weird, anxiety-producing, claustrophobic, and triggers a sense of panic. Now, the biggest question is who are the types of UARS patients that would feel so negatively about exhaling on PAP therapy?

In our clinical and research experience, it would be someone who already has some degree of anxiety, a lot or a little, it may not matter, because once they try to use fixed CPAP in particular, they quickly report that it’s very uncomfortable or worse, they report feeling more anxious.

In a large proportion of these patients, we switch them to bilevel during the pre-sleep desensitization/adaptation period, and remarkably, we have found that 90% of these patients report immediate relief by virtue of the lower expiratory pressure.

Note: Bilevel combines IPAP (pressure on Inhalation) and EPAP (pressure dropping on Exhalation).

Can You Feel Anxiety in your Sleep?

Although we have more recently discovered that most patients want to switch to bilevel during the desensitization, that is, before the formal titration begins, we didn’t really figure out this point until we watched UARS patients while asleep. That’s when we saw that they did not like CPAP, that is, a fixed pressure on exhalation. That’s when we saw the ratty looking signal suggesting they were having some kind of anxiety or otherwise unpleasant response to air coming in while they were trying to breathe out.

In my opinion, which I don’t think is shared by the majority of sleep docs, anxiety is experienced while you sleep. If you can experience anxiety in dreams, I don’t see why you can’t experience anxiety to pressurized airflow in your sleep. So, in a nutshell, I think that’s why CPAP doesn’t work well in UARS patients and for that matter, I don’t think it works well in most SDB patients except for truly classic hypersomnolent, anxiety-free, sleep apnea cases.

I think anxiety is already present in the majority of SDB cases, because it is an anxiety-producing experience to breath abnormally all night long. That is, anxiety and breathing are intimately connected, so most SDB patients are more or less conditioned to be more nervous in general by having spent the night not breathing well. Now, introduce a foreign stimulus, CPAP, which then triggers or worsens anxiety by the introduction of an extremely foreign sensation: pressurized airflow forced inward during exhalation.

Is Bilevel the Answer?

Why bilevel works so well is still a puzzle. But, what’s so intriguing is that the subjective and objective findings match. That is, nearly all patients who switch from CPAP to bilevel state that it is easier (subjectively) to breathe out with bilevel. And, during their titrations, the ratty airflow signal disappears on expiration (objectively) and is replaced by a smooth and rounded curve indicating normal expiration.

Should you be able to produce the same results with CFLEX, APAP, etc? Presumably so, except for one “large” difference. You cannot generate the same gradient or gap between IPAP and EPAP with any of the other devices. And, in our clinical and research experience, we are using gaps of 4 to 12 cm of water in our patients. My personal bilevel settings are 21/12.5 for a gap of 8.5.

In our prescriptions for bilevel, I would venture that the average gap is in the 5 to 6 range with tremendous variation, including some with a gap of only 2 or 3. Those with a lower gap requirement would likely do as well on FLEX or APAP, but to repeat, the large majority of our patients have a gap of 4 or greater.

Still, it would be nice to have a respiratory physiologist explain to us why the larger gap is so effective. As an internist and sleep medicine physician, there are only two obvious theories that stand out. First, what if we’ve always assumed, mistakenly, that airway pressure had to be constant for both inspiration and expiration? I think it has already been proven by other researchers that you actually need higher pressure to keep the airway pinned open on inspiration and a lower pressure on expiration. If that’s so, then is bilevel the best system because it provides the exact pressure you need (not too much and not too little) during expiration.

The second idea relates more to the psychophysiological response to PAP therapy. Maybe the larger gradient simply gives the patient a distinctly more comfortable feeling, because the lower pressure creates a feeling so much closer to breathing normally (without PAP). If this theory were accurate, though, it would imply that over time as you get used to any sort of PAP therapy, then perhaps the gap would narrow and eventually you could use fixed CPAP again. If this were true, I would expect more people to eventually adapt to fixed CPAP pressure, and I don’t believe that’s occurring.

UARS Diagnosis and Medicare

Last, insurance coverage for UARS is always a hot topic. This section is not relevant to titrations, because nearly everyone manifests UARS on the titration. Insurance questions revolve around the diagnostic study: does the patient “only” have UARS?

In Albuquerque, I have pushed back on this issue for more than a decade, and the results have been tangible and somewhat satisfying. At this point, there are only 3 insurance carriers in New Mexico who do not cover treatment (specifically, PAP therapy or oral appliances) for UARS. Even among these 3 carriers, we can always make an appeal on very specific comorbidities (e.g. a UARS patient who has had 2 car accidents in the last year), then Medicare might decide to cover such a UARS patient.

In the beginning of this particular journey, I found it frustrating at first, but it was also an opportunity to educate medical directors at insurance companies. We would routinely call these individuals, send them research publications, and explain how UARS was going to cost them more money in the long-run if they didn't cover it.

As an aside, I have to mention how frustrating and disappointing it is to hear about sleep physicians who might make their decisions about UARS based on insurance considerations. I was never trained to think that way in medical school, and it approaches unethical behavior in my opinion. If a patient is diagnosed with UARS, that's the diagnosis whether it's covered by insurance or not. Insurance companies don't tell me what I can diagnose and they don't tell me how to treat my patients!

Financial considerations are relevant and important, but they have nothing to do with my patient advocacy and my duty to inform the sleep patient of the diagnosis and treatment plan we recommend.

I am deeply perplexed by the notion that a sleep physician would withhold this information from a UARS patient because the insurance company wasn't going to cover it. As before, it borders on unethical behavior, in my opinion.

Summing Up

Last and not least, UARS is one of the primary reasons that many SDB patients do not achieve an optimal response. As I describe at length in my book, it is a human tendency to "normalize" behaviors, which over time prevents us from obtaining the best possible response to PAP Therapy. If you are so used to fatigue and sleepiness, having suffered for so many years, then how could you possibly discern what a normal level of sleepiness and fatigue should be? Instead, (and I know this from my own trials from CPAP to APAP and finally bilevel), when you experience some improvement, the tendency is to create a new "normal" and wrongly assume that this is "as good as it gets."

Well, it's not as good as it gets if the UARS component of the SDB hasn't been treated, because there is still more to treat. Undoubtedly, most of the members of this forum recognize the fine-tuning and tweaking that's needed to manage mask leaks, mask comfort, mouth breathing, humidifier settings, and nasal congestion, just to name a few of the issues that must be regularly attended to enhance the PAP response.

Notwithstanding, in my clinical experience, I have found that resolving the UARS component of SDB is in the top tier of factors that frequently must be addressed to achieve optimal results, especially so among patients whose regular use of PAP therapy has not yielded the desired effects.

I've lived through this problem and I've breathed through it, and no other single factor enhanced my sleep quality to the level I currently enjoy and am eternally grateful for experiencing.

Surely, this is something to sleep on. I do, night after night.

P.S. Sorry for the long post; but it's not my fault, it's the bilevel. After 7 near perfect hours of sleep quality last night, I had to do something to burn up the energy.

Thanks for bringing this insight to us Dr. K, but I have to ask WHY is it that the American Academy of Sleep Medicine has NOT bought into Dr. Guilleminault's UARS findings?

My understanding is UARS remains controversial. It is also my understanding that most medical insurance still does NOT cover a UARS diagnosis, WHY is that?

Why hasn't there been any other parallel studies done by other Sleep Research institutes to confirm Dr. G's original findings (or I haven't found them yet)? If there have been other studies completed, it would seem insurance would have no choice but to cover UARS.

My understanding is UARS involves nearly everything north of the vocal cords, if that is true, then WHY does the UPPP procedure fail so miserably? What is your findings on the efficacy of UPPP procedure on UARS?

You suggest that if we control UARS with xpap, that we may see an end of our residual daytime fatigue?

I use a machine that says it effectively reduces my SDB events down to below AHI=5, the number of FL runs seen on my 420e reports is miniscule, while my A-Flex also records FL's, I don't assume that machine to be very accurate on that front, some nights it may score 1 or 2 (should NOT be enough to impact my sleep) at least with my 420e I see them scored.

For the past 6 or 7 years I've been searching for a solution to that daytime fatigue, the only answer my ABSM sleep doc has been able to suggest is those spontaneous arousals.

My last PSG was a bi-level titration, it didn't seem to improve my spontaneous arousal indice any, in fact it made my SDB worse so they switched back to cpap, I was still left with a RERA=27 to 29 per hour on the hose when it was all said and done....and still tired during the day.

Without having to buy a book, can you show us research WHERE the number of spontaneous arousals decrease switching from use of CPAP therapy to Bi-level therapy by use of a higher IPAP/EPAP spread?

But it would seem to me, if use of Bi-level use so easily eliminates FLs as Dr. K suggests (and reduces spontaneous arousals seen during a PSG) that information would be coming out of the woodwork at nearly every sleep lab across the country.

Mindy, if the Respironics machine lets you set equivalent top and bottom pressures, you may get CPAP treatment with APAP recording.

O.

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mindy wrote:

DreamStalker wrote: However, without another sleep study, I have no idea if indeed I am experiencing UARS or not (I guess the P&B 420E is the only machine that records FLs?). I don't consider myself to be prone to anxiety (at least not while awake).

DreamStalker, if you've got the M-Series A-Flex, that will record FLs if you're in APAP mode. Since I just switched to CPAP mode, I've found that they are no longer recorded. I have no idea what are "good" numbers of FLs.....

Mindy

What about snores-how should we view them.

[quote="Snoredogis it that it did not record them in that mode or that the mode eliminated them?

(personally, I don't think that machine does a very good job at counting those where it would be useful).[/quote]

Snoredog,

I don't think it records them -- the graph with FL's doesn't appear in the EncorePro output for days in CPAP mode.

Thanks for the heads up about accuracy questions!

Mindy