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Re: Sleep Doctor Visit: Aerophagia and Changing Our Pressures...
Posted: Wed Aug 18, 2010 11:22 am
by SleepingUgly
I can't think of any viable explanation for why your body would "get used" to a particular pressure level and then rebel against a different one. I think that from night to night, you're starting with a clean airway slate. I don't have any data to back up my opinion, but I've never seen any to suggest that our bodies get used to a particular pressure and then we can't lower it or the body rebels either.
Re: Sleep Doctor Visit: Aerophagia and Changing Our Pressures...
Posted: Wed Aug 18, 2010 11:35 am
by ozij
You seem to be pretty far away from the doctor's preferred "less than 5". Perhaps you can call and ask him what he thinks would help?
If it were me, I would look for the pressure that gave me the lowest AHI - not matter what that AHI consisted of. I think 3 breathing interruptions an hour are preferable to 12. I'm pretty sure your doctor would agree to that.
Re: Sleep Doctor Visit: Aerophagia and Changing Our Pressures...
Posted: Wed Aug 18, 2010 11:40 am
by klgm326
Thanks, Guys! I agree...I don't like having 11+ events per hour! And I am very very tired today! I hate to go against doctor's orders, but something isn't working here...I may try one more night and then give him a call tomorrow if those numbers are still that high.
Re: Sleep Doctor Visit: Aerophagia and Changing Our Pressures...
Posted: Wed Aug 18, 2010 11:58 am
by SleepingUgly
ozij wrote:I think 3 breathing interruptions an hour are preferable to 12.
Just to clarify what I was saying earlier, lest my message be misinterpreted. Ozij is right--no one would argue that 3 is not better than 12. Although it's not clear how the cutoff of 5 was selected, everything below 5 is considered "normal". There is no data to suggest that any differences below 5 are clinically meaningful. Try for as low as you can get, but don't obsess about the small differences within the normal range, especially if you don't feel a difference between them.
AHI Took Root at Stanford in '73
Posted: Wed Aug 18, 2010 11:08 pm
by -SWS
This excerpt from
Promise of Sleep describes how Stanford sleep medicine pioneers William Dement and Christian Guilleminault devised an AHI-of-5 as the original apnea/hypopnea clinical cut off in 1973:
William C Dement in [i]PROMISE OF SLEEP[/i] wrote:In 1973 Christian Guilleminault and I proposed the measure that is still used for the clinical definition of sleep apnea and for rating its severity. We called it the Apnea/Hypopnea Index (AHI). Hypopnea is the term we use when the throat doesn't quite close entirely, but air flow is reduced sufficiently to lower oxygen and cause an arousal. The AHI score represents the average number of Apnea and Hypopnea episodes that a patient has during an hour of sleep. We decided that an AHI of 5 should be the lower limit for making a diagnosis of apnea, so a score of less than 5 (breathing stops fewer than 5 times per hour) is considered too low for clinical diagnosis and doesn't require treatment. However treatment may be necessary if a patient has an AHI of 5 to 10 with other signs or symptoms of apnea such as daytime fatigue or high blood pressure. Although not all my colleagues agree, I feel strongly that people with an AHI of 10 to 20 should definitely consider treatment, even if they are not feeling sleepy during the day. In my opinion, anyone with a score over 20 should always be treated - they will soon have a serious, life-threatening problem."
Sleep medicine and Medicare still adhere to Dement's and Guilleminault's AHI-of-5 as clinical cut-off criterion to this day.
Below is a recap of one classic debate between doctors Sullivan and Rapoport, two sleep medicine legends in their own right. They argue AHI's usefulness as an apnea/hypopnea severity marker in the year 2002:
http://www.respiratoryreviews.com/sep02 ... Index.html
[edited to update broken link]
Re: Sleep Doctor Visit: Aerophagia and Changing Our Pressures...
Posted: Thu Aug 19, 2010 4:59 am
by klgm326
Well, the good news is....last night, I slept in my Swift LT for Her and was back down to AHI of 3!! Interesting...All else staying the same, it appears that my body did not care for the Liberty Hybrid! The 2 nights I spent on the Liberty had much higher AHI! Switching back to straight nasal pillows with mouth taping seemed to do the trick...interesting...
Thanks for all the support! I will continue to watch this...
Re: Sleep Doctor Visit: Aerophagia and Changing Our Pressures...
Posted: Thu Aug 19, 2010 6:34 am
by -SWS
klgm326 wrote:Well, the good news is....last night, I slept in my Swift LT for Her and was back down to AHI of 3!! Interesting...All else staying the same, it appears that my body did not care for the Liberty Hybrid! The 2 nights I spent on the Liberty had much higher AHI! Switching back to straight nasal pillows with mouth taping seemed to do the trick...interesting...
Thanks for all the support! I will continue to watch this...
Klgm326, a few possibilities come to mind regarding your AHI variability. One is sleep position; many people experience more severe sleep apnea while sleeping on their backs, while a few experience increased severity while side sleeping. Another possibility is excessive leaks; more than a few of our posters over the years have reported being prone to AHI spikes amidst leaks. A third possibility is that the Liberty might have facilitated mouth breathing; mouth breathing, in turn, seems to increase airway resistance/collapse in some patients.
Here's a relevant citation SleepingUgly shared with us a few months ago regarding that last possibility:
http://erj.ersjournals.com/content/22/5/827.full
ozij wrote:You seem to be pretty far away from the doctor's preferred "less than 5"... I would look for the pressure that gave me the lowest AHI - not matter what that AHI consisted of. I think 3 breathing interruptions an hour are preferable to 12. I'm pretty sure your doctor would agree to that.
That was so succinct and so logical that I just had to quote it.
Re: Sleep Doctor Visit: Aerophagia and Changing Our Pressures...
Posted: Thu Aug 19, 2010 3:25 pm
by klgm326
...a few possibilities come to mind regarding your AHI variability. One is sleep position; many people experience more severe sleep apnea while sleeping on their backs, while a few experience increased severity while side sleeping. Another possibility is excessive leaks; more than a few of our posters over the years have reported being prone to AHI spikes amidst leaks. A third possibility is that the Liberty might have facilitated mouth breathing; mouth breathing, in turn, seems to increase airway resistance/collapse in some patients.
Here's a relevant citation SleepingUgly shared with us a few months ago regarding that last possibility:
http://erj.ersjournals.com/content/22/5/827.full
@SWS...I think that's me!! The leak rate wasn't it...it was one of my lowest yet...1.2!! Position...same! -- mainly side. So, the mouth breathing has to be it! And the Liberty seems to follow the same concept as the test study - nasal mask and separate mouth mask. Interesting...Well, I'm very grateful to all of you and for having the capability of seeing my own data. I might have gone on like this thinking all was great and wondering why I was so tired. I did wake up today feeling better...not great, but not so YUCK like the last two days. (My husband also said that I seemed the most peaceful he's seen me in the month I've been doing this...and it was with a Swift LT I just decided to bid on on Ebay out of curiousity...go figure!)
Thanks again!!