Hello Guest, Welcome to Apnea Board !
As a guest, you are limited to certain areas of the board and there are some features you can't use.
To post a message, you must create a free account using a valid email address.

or Create an Account


New Posts   Today's Posts

First Night: Burst of Events?
#1
My first night I had an AHI of around 1.2 if you ignore a burst of about 25 events around 12:30 that went on for about 30 minutes. I don't see what caused these, attached are screen shots looming in on that point in time, can someone make suggestions please?

[Image: 2cqglGb3XtM6.png]
.
[Image: 2cqh27u1rnYM.png]
.
[Image: 2cqhEcCfxJk9.png]

In the first image you can see 8 large leaks, those are my nose scratching events. Also, comparing these to my S+ data, there is an event here every time S+ recorded me waking up, however I did not wake up (S+ did not record it) every event - so, I assume some of these are non-arousal events.
I am not a Medical professional and I don't play one on the internet.
Started CPAP Therapy April 5, 2016
I'd Rather Be Sleeping
Reply
#2
I wonder if you would not be served better by switching to Auto and bracketing your 10 cm-H2O pressure. Perhaps 9 to 12?

Or, lower EPR. Your pressure drops to 7 on exhale; and your airway may be collapsing with only 7 on EPAP. Yeah, reduce EPR from 3 to 2 and watch your graphs. Remember, one night does not make a trend.

Any idea what your sleeping posture was at that time. i.e. -- were you sleeping on your side then rolled on your back?
INFORMATION ON APNEA BOARD FORUMS OR ON APNEABOARD.COM SHOULD NOT BE CONSIDERED AS MEDICAL ADVICE. ALWAYS SEEK THE ADVICE OF A PHYSICIAN BEFORE SEEKING TREATMENT FOR MEDICAL CONDITIONS, INCLUDING SLEEP APNEA. INFORMATION POSTED ON THE APNEA BOARD WEB SITE AND FORUMS ARE PERSONAL OPINION ONLY AND NOT NECESSARILY A STATEMENT OF FACT.
Reply
#3
I am pretty certain I was on my side. It could well be that I woke because of an event, felt an itch coming on, scratched my nose (pulled mask out and scratched, then reseated it) and then laid on my back to go back to sleep. I know that happened at least once and I don't know if that was at the time.

That is roughly 1 event per minute (60 AHI), I would think I would have woken up with all those going on? So, my second thought was maybe it was not real, and something like the leaks caused it?

I have switched the exhale reducing (forgot the acronym) off for tonight to see if that affected it. In my titration study my events were close to zero at 10 in CPAP mode, BiPAP mode was worse. and the doctor wanted me to start off in CPAP and not APAP (I cheated and got an Autoset upgrade).
I am not a Medical professional and I don't play one on the internet.
Started CPAP Therapy April 5, 2016
I'd Rather Be Sleeping
Reply


#4
(04-06-2016, 12:36 PM)FrankNichols Wrote: I am pretty certain I was on my side. It could well be that I woke because of an event, felt an itch coming on, scratched my nose (pulled mask out and scratched, then reseated it) and then laid on my back to go back to sleep. I know that happened at least once and I don't know if that was at the time.

That is roughly 1 event per minute (60 AHI), I would think I would have woken up with all those going on? So, my second thought was maybe it was not real, and something like the leaks caused it?

I have switched the exhale reducing (forgot the acronym) off for tonight to see if that affected it. In my titration study my events were close to zero at 10 in CPAP mode, BiPAP mode was worse. and the doctor wanted me to start off in CPAP and not APAP (I cheated and got an Autoset upgrade).

I think that's a good idea. It might also reduce CAs since EPR can induce CO2 washout.
With EPR=3, you are in effect running a Bilevel machine with a PS of 3.

BTW -- you might rescale the Y-axis on the leak graph to perhaps 50.
INFORMATION ON APNEA BOARD FORUMS OR ON APNEABOARD.COM SHOULD NOT BE CONSIDERED AS MEDICAL ADVICE. ALWAYS SEEK THE ADVICE OF A PHYSICIAN BEFORE SEEKING TREATMENT FOR MEDICAL CONDITIONS, INCLUDING SLEEP APNEA. INFORMATION POSTED ON THE APNEA BOARD WEB SITE AND FORUMS ARE PERSONAL OPINION ONLY AND NOT NECESSARILY A STATEMENT OF FACT.
Reply
#5
Thanks, I have zoom din on Leak rate and Mask Pressure. The original post images are updated.
I am not a Medical professional and I don't play one on the internet.
Started CPAP Therapy April 5, 2016
I'd Rather Be Sleeping
Reply
#6
That burst occurs about 100 minutes after you went to bed, which points to the possibility that its REM related.

Did you have a formal titration study? If so, how much REM was recorded when they were titrating you?

It looks to me like you may need more pressure in REM than in non-REM.

If you want to switch to APAP, I'd suggest a range of 10-12 to start with.
Questions about SleepyHead?
See my Guide to SleepyHead
Reply


#7
(04-06-2016, 05:18 PM)robysue Wrote: That burst occurs about 100 minutes after you went to bed, which points to the possibility that its REM related.

Did you have a formal titration study? If so, how much REM was recorded when they were titrating you?

It looks to me like you may need more pressure in REM than in non-REM.

If you want to switch to APAP, I'd suggest a range of 10-12 to start with.

Hmm, the more I read the smarter you look!

That period did correlate to a REM period in my S+ data.

In my first sleep study I had 1 REM period and it was brief. I don't recall right now, but I think I had 2 or 3 in the titration study.

I am taking justMongo's advice tonight and turning off the EPR, since I did do so much worse on BiPAP in the titration study and the EPR looks a lot like BiPAP. Also, the doctor picked the 10 because higher began to trigger CA's. I am seeing some CAs on my chart from last night, but I am trying to be patient (which I am not) and deal with the OA's first If I can get them under control, then I will see how to deal with the OAs.

As fro APaP mode, I am debating. Every few minutes I switch between yes, and no, wait until after the compliance test period, then I can go wild and fiddle all I want.

Thing is, I think I doctor thinks I will end up with a ASV machine, but wants to go through the steps and not just leap into it. So, I don't want to do anything to spoil the data and his plan...

I will see how tonight goes and if it is at all better, then maybe in a day or two I will try moving the pressure up 1 and see how that works.

Thanks for the advice.
I am not a Medical professional and I don't play one on the internet.
Started CPAP Therapy April 5, 2016
I'd Rather Be Sleeping
Reply
#8
Okay, the second night I had another burst of events that lasted about 30 minutes. This time they were UAs where last time they were OAs. Also, this time there was no related REM sleep during the 30 minutes.

It's looking more like possibly leak related?

I am going to address the leak issues I am having tonight before drawing any more conclusions.
I am not a Medical professional and I don't play one on the internet.
Started CPAP Therapy April 5, 2016
I'd Rather Be Sleeping
Reply
#9
(04-07-2016, 07:56 AM)FrankNichols Wrote: Okay, the second night I had another burst of events that lasted about 30 minutes. This time they were UAs where last time they were OAs.
The machine scores apneas as "UAs" (unclassified or unknown) apneas when the FOT algorithm cannot determine the patency of the airway.

The most common reason the FOT algorithm fails is the presence of leaks that are large enough to make it difficult for the machine to track your breathing.

Quote:It's looking more like possibly leak related?
Leaks could explain why the apneas were listed at UAs.

But leaks would probably not be the cause of a whole string of apneas happening in the first place. Unless the leaks were repeatedly waking you up and the apneas are occuring just as you're trying to get back to sleep. In which case they could be mis-scored sleep onset centrals, which are usually considered normal. Unless they're happening so frequently that can never make it over the hump of sleep transition and actually get t sleep.

It would help to see the data.

Quote: Also, this time there was no related REM sleep during the 30 minutes.
How does the device you are using to track sleep stages work? And what is its accuracy?

REM sleep can be quite difficult to pick up for a number of reasons. The old (defunct) Zeos which used EEGs were only abotu 75% accurate at distinguishing REM according to the fine print stuff that Zeo wrote in their owners guides. Accurate enough for home use, is how they put it.

Questions about SleepyHead?
See my Guide to SleepyHead
Reply


#10
(04-08-2016, 07:59 AM)robysue Wrote: How does the device you are using to track sleep stages work? And what is its accuracy?

REM sleep can be quite difficult to pick up for a number of reasons. The old (defunct) Zeos which used EEGs were only abotu 75% accurate at distinguishing REM according to the fine print stuff that Zeo wrote in their owners guides. Accurate enough for home use, is how they put it.

The device is the ResMed S+. Based on what they have said in the marketing, the device is basically a RADAR unit that uses a frequency at which the clothing, blankets, etc. are transparent, and the body (water mostly) is opaque. It then monitors the movement of the body, I assume by doppler effect. I have not found a technical description of the methodology yet, but I expect it uses a something along the lines of an FFT of the doppler shift rates to create a frequency signature of the movement over a period of time. Then that signature is applied to some form of comparison algorithm (probably an AI Neural net?) that has been taught what various sleep stages "look like".

All that is probably wrong - but... I wrote the software for a similar idea ages ago that was used in a system for cargo ships where the system listened to bearing noise in the drive shaft and predicted when the bear was going to fail, so preventative maintenance could be performed before heading out from a ocean crossing. The system was expanded to "listen" to entire machine shops and make predictions of all the various pieces of equipment, mills, presses, lathes, etc. from the composite noise based on recognizing how each piece of equipments signature sound was changing. Towards the end of my involvement in that product we were able to create usage reports indicating how each piece of equipment was being used in the busy machine shop, correlate that to which machinists were assigned to or using each and determine if someone needed additional training on proper techniques to reduce machine maintenance times.

Anyway, back to S+. If I recall correctly ResMed claims to have tested/trained their system in numerous Sleep Labs during clinical sleep studies and it performed with a reasonable accuracy when compared to the studies results. Since it is not sold as a medical device, "reasonable accuracy" is what ever someone wants it to be.

In my case, I am tracking my CA's and OA's in SH and comparing them to my arousal events reported by the S+. There is an almost 100% relationship between a waking event on the S+ and an apnea event in SH. Of course not all apnea events result in an arousal event, and so there are many OA's and CA's that do not result in my waking up. Also, I can't say how many times the S+ misses me waking, I can only say it is "reasonable" that I would have woken at the reported time because there was a long duration Apnea event (30seconds or more) at the same time the S+ says I woke.

Added to that times that I know I woke because I noted the time on a clock before going back to sleep.

I have not figured out how to determine the validity/accuracy of the light sleep periods reported by the S+.

There is a strong correlation between being woken from deep sleep (according to the S+) and my feeling very "groggy".

On REM stage, in all cases where/when I recall being woken from a dream, the S+ reported I was in REM stage.

I have only been woken a low percentage of the times the S+ reports I am in REM, so it will take a while to draw any conclusions. But it is 100% so far in that specific case. Obviously you dream mostly (not necessarily only) in REM so it is not a perfect qualification.

Also, the S+ may be missing REM states - hard to know what is not there and I don't wake up.

Back to the AHI I am seeing. Yesterday I spent some time adjusting and fiddling and got rid of most mask leaks. Previously the leak rate was running around a constant 20L/min I have it now down to around 4L/min. (sadly shaving my short beard was a major contributor to improving my leak rate - sigh.)

Quote:But leaks would probably not be the cause of a whole string of apneas happening in the first place. Unless the leaks were repeatedly waking you up and the apneas are occuring just as you're trying to get back to sleep. In which case they could be mis-scored sleep onset centrals, which are usually considered normal. Unless they're happening so frequently that can never make it over the hump of sleep transition and actually get t sleep.

This comment I think is right on. What I "think" is happening now, with the leaks reduced, is that I have an arousal event that results in my tossing and turning, which results in my hitting my mask and a major leak occurring. Then I wake enough to adjust the mask and try to go back to sleep. (This awakening is reported by the S+). Then "sleep onset" Centrals occur causing the entire sequence to repeat - often, not always.

So I am going to try going to sleep on my side and not my back to see if that reduces the sleep-onset centrals and focus on not tossing and turning - well, I can try to anyway.

Thank you for your insight, I appreciate it.
I am not a Medical professional and I don't play one on the internet.
Started CPAP Therapy April 5, 2016
I'd Rather Be Sleeping
Reply


Possibly Related Threads...
Thread Author Replies Views Last Post
  92 events easkey 3 175 01-10-2017, 07:51 PM
Last Post: trish6hundred
  Variable events per hour a3sulliv 8 362 12-20-2016, 11:19 PM
Last Post: trish6hundred
  False events in SleepyHead marcus10 5 335 12-18-2016, 09:16 PM
Last Post: srlevine1
Question 4 Days on first Smart Machine (Good AHI, but lots of events) kacn6771 6 401 12-16-2016, 11:00 AM
Last Post: Sleeprider
  [Equipment] Mask Events suddenly showing up gillw 3 178 12-12-2016, 08:18 PM
Last Post: trish6hundred
  Respironics 9 minute cycle with no events. pixpop 2 186 12-06-2016, 09:17 PM
Last Post: trish6hundred
  2015 peer reviewed article on how xPAPs score events and auto algorithms respond robysue 1 213 12-03-2016, 07:48 PM
Last Post: Perchas

Forum Jump:

New Posts   Today's Posts




About Apnea Board

Apnea Board is an educational web site designed to empower Sleep Apnea patients.

For any more information, please use our contact form.