Results of first 2 weeks using PAP therapy...more questions!

Hi all,
Some of you may have read my first thread last week and be aware that I'm new to OSA, CPAP, AHI, AI and all the other acronyms that seem to be associated with this condition In any case, I'm happy and committed to managing my own therapy and have no problems with trying different things in order to get my OSA under control.

I've now been using PAP therapy for 11 nights over the past 2 weeks (2 nights off due to severe flu i.e. bad chest cough, blocked nose etc) and have been tracking my progress with the ResScan 3.3 software. I initially experimented with a number of different factors in my therapy but was advised here to introduce changes slowly so I stopped doing this. But, some of my stats are still raising questions for me. The following info may help:

• *I was initially diagnosed in my sleep study as experiencing Non-REM AHI of 42 and REM AHI of 60 events per hour
  *Titrated pressure during subsequent titration study is 13cm but my early experimentation with Auto pressure appeared to average between 11 and 12
  *My median AI (events p/h) for the past 2 weeks is 2.8 but has blown out to anywhere between 7 and 10.7 on some occasions.
  *My median HI (events p/h) has been 10.0 but has blown out to 16 on some occasions
  *My median AHI is 12.8 but have experienced 5 (out of 11) nights between 19 and 27.....which concerns me a bit!
  *I can sleep a full night using therapy with only a couple of minor awakenings (going to bathroom, tube occasionally getting snagged etc). No trouble going back to sleep.
  *I average between 7-8 hours sleep per night, all with mask
  *No problems with getting accustomed to 'pressure' sensation
  *I like the Swift II mask & it seems to fits me well
  *No major problems with mask leaks. Of course, these do occur but I'm getting much better at avoiding these
  *I seem to have adjusted really well to the therapy and never have to fight an urge to remove the mask etc. In fact, I don't even really notice that I'm breathing against pressure at all......another thing which concerns me i.e. is this normal? Even with pressures up to 14 I hardly even notice it.
  *I'm a professional sax player (for all of my career) and have read some info which seems to indicate that sax and trumpet players are significantly more prone to OSA due to the very high neck/throat pressures when playing and subsequent over-development of the neck/throat muscles and tissues....which then tends to cause airway constriction when these muscles/tissues are relaxed.

So, my sleep stats have been all over the place for the past 2 weeks and I've been trying to determine if there are any particular correlations between the different variables involved (eg. pressure, leak, AHI, HI etc) and my sleep stats. Different pressures don't seem to be making much difference overall.....it almost seems like each night is "pot luck" and as I'm a pretty logical thinker, this is driving me nuts.

I realize that I'm still in the very early stages of therapy but am wondering if these "roller-coaster stats" are normal? If not, what is normal? But if so, (and given all of the info above), is there any particular time period when these should start to level out?

Also, is it normal for the HI to be consistently much higher than AI? Are there any particular things I can check or implement that can reduce this factor? I've been wondering if I should experiment with auto mode between 13 and 16cm to see if the increased base pressure reduces the HI......but given that the Auto pressure averages between 11 and 12 I'm not sure that this would be a good idea.

Any ideas folks? Sorry for such a long post and all the questions......I just really want this to work and am still unsure of so many things! (And I'm tired of being kicked out to the spare bedroom by my wife...... )

Cheers
Gary

_________________

CPAPopedia Keywords Contained In This Post (Click For Definition): swift, Titration, CPAP, AHI, auto

Gary:

My HI is usually higher than my AI, but it's AHI that I track. I can appreciate your desire to understand it all, but it sounds to me like you're getting into it really well.

I didn't grasp whether you're using APAP, and if so, what the range is. My experience was that it worked better for me as I narrowed the range, and I finally went back to CPAP.

If you're not feeling the pressure, that suggests to me that you're adapting pretty well. The sax may be the reason. I can clearly remember the day I woke up thinking the machine had failed during the night because I didn't feel the pressure. I knew I was on my way!!

Keep a close eye on leaks. I think the ResMed lets you enter the mask and it reports the leaks above the rated leaks, so check on how that's set up, as leaks not only mean lost therapy, but cause the machine's interpretation of your events to be off.

I'm sure you'll get lots of good advice from more experienced users than me, but it looks to me as though you're doing really well.

Another post on the forum said that Resmed machines often show a high HI because they detect snores and flow limitation as an HI when they may not actually be a hypopnea.

I'm far from an expert on the subject considering I picked up my APAP on Wednesday, but I had low AI (.01) for the first 4 nights, and today it was an AI of 4.0. My HI events are between 3.0 and 7.0.

I have the same issue that you have. Do you use the "Settling" feature?

I was researching the "Settling" feature today. I *think* settling is a time period that you can set at the start of the night to ignore AI and HI events that the machine detected while you are still awake. Sometimes I breath wierd when I first put on the mask and adjust it. I'm thinking that some of the AI and HI are recorded by the machine while I'm actually awake.

I'm thinking that if I enable the settling feature I'll get more accurate data and lower AI and HI.

Maybe you're experiencing the same thing. Does your software show a lot of events at the start of the night, or during the times when you wake up and reposition before falling asleep again?

I also heard that the pressure reading in the morning is not the highest the machine went to. It's supposedly the average or something.

Does anyone think that some of these high numbers can be caused by breathing activity before falling asleep or by fiddling with the masj?

Hi Panhandler, and thanks for the reply. I'm "supposed" to be using CPAP only (my sleep physician is against APAP) but tried APAP a couple of times early on to see how it felt, and also to see what the APAP median pressure was. My titrated pressure was 13cm but the auto pressure on my AutoSet Spirit II seems to hover between 11-12cm when I've tried APAP.

I can clearly remember the day I woke up thinking the machine had failed during the night because I didn't feel the pressure. I knew I was on my way!!

Yep, that's exactly how it feels!

And yep, the ResMed allows me to enter the mask (which I've done).....though I'm still a bit unsure of how to interpret the stats re. leakage above the rated leakage.

2 week leak summary stats are (according to ResScan):

• *Median = 2.4 (L/min)
  *95th percentile = 20.4
  *Maximum = 31.2

Last night's stats are:

• *Median = 1.2 (L/min)
  *95th percentile = 12.0
  *Maximum = 30.0

I'm pretty certain that the couple of maximum leaks simply reflect those occasions when I took the mask off when getting up to go to the bathroom etc and didn't stop the machine (thus recording a sharp spike).....and there are only ever a couple of isolated max. spikes on the graphs and that seems to confirm this.

And I just checked this site for mask leakage rates (though it only mentions the Swift, not Swift II) and the leak rate for 13cm is 38.6 (I have no idea if this is L/min or what!) and for 11-12cm is between 35-37. Can anyone confirm how my leak rate stats are comparing with the mask's rated leakage?

Sleet wrote:Do you use the "Settling" feature?

Yeah, most of the time, though I've turned it off on a couple of occasions to see if it makes any difference to the whole experience......I guess it's better for helping my wife to fall asleep as it's quieter, but as mentioned in my first post, I don't even really notice the high pressures so I guess it doesn't do much for me!

Does your software show a lot of events at the start of the night, or during the times when you wake up and reposition before falling asleep again?

No, the software doesn't show a lot of events at the start of the night, but it could be showing a lot of events when I wake and reposition etc. I usually can't remember exactly what time I woke up and therefore whether the events on the graph occurred before I woke up, or after. I might have to start noting these times to check.

Madcow, welcome. to answer a few of your questions, yes, some 'rollercoater' stats are to be expected, especially in the beginning. Leaks will play hob with your stats, too.

Sleet is correct about what settling is and does. The machine does not score (or respond) to any events during the settling time. Keep that time as short as possible. Pressure will gradually rise from the starting level you set up to your lower pressure setting over that period of time, allowing you to get off to sleep before reaching full pressure. Set it just long enough to get to sleep on an average night. You can always it if you are having trouble getting to sleep on one particular night. Ramp works the same way in cpap mode, except the rise is to your full set pressure (since there is no range in cpap mode).

The mask feature in the ResMed machines is limited to ResMed masks. Of course, you can use other brands of masks, but the machine won't match the vent rate correctly for them in the statistics. Note that this does not affect your therapy, only your statistics for leaks. If the mask you use comes reasonably close to the vent rate of a ResMed mask, you are good to go, stats wise. Otherwise, just use the "Standard" setting.

Here is a chart to help you match the vent rates to the ResMed machines:

http://www.internetage.com/cpapinfo/leak-rates-1.html

Good luck!

Gary,

Sounds like you have adapted to the mask and breathing against pressure, two significant hurdles in adapting to CPAP. Congratulation on this.

I use the S8 Elite, the straight CPAP cousin to the Vantage, your machine. I also get my data straight from the LED screen, no software. From the reading I have done and my own experiance, it seems that the Resmeds do score high on the HI numbers. As I understand it, both machines work the same as far as displaying leak rate. If I have selected my mask in the clinicians menu, my machine automatically subtracts the mask's normal exhaust leak rate from the total leak rate, so that any leak shown on the screen is "bad" leak, not normal leak.

Have you tried taping your mouth for a few nights to see if you are breathing or leaking air out your mouth? If your AHI is going all the way up to 27 something is going wrong somewhere, and this is a quick, simple and cheap way to eliminate the possiblity of a real problem. If you are leaking out your mouth, it would explain the broad swings in your numbers. If it were me, I would give it a try. Best of luck!

Hi again all,
Well, I taped my mouth shut last night and whilst the leak results are pretty darn impressive, I actually had my worst night yet as far as the other stats are concerned.

Here they are:

• *Auto pressure setting: 10cm - 13cm
  *Actual pressures: Median: 10.2, 95th percentile: 10.4, Maximum: 10.6
  *Leak: Median: 0.0, 95th percentile: 2.4, Maximum: 21.6 (2 spikes when I took off the mask without stopping the machine)
  *AI/HI/AHI: AI: 7.2, HI: 20.5, AHI: 27.7

Any thoughts guys? I'm a bit puzzled as to how my AI/HI/AHI could possibly be so high.....the worst so far!

Also, I only used wide, clear packing tape over my mouth 'cause that's all I had and it was pretty tight, but is it normal to drool a bit when your mouth is taped shut? I'm also puzzled as to how that could happen. I figure the tape tension gradually slackened off but it wasn't the greatest experience in the world waking up with that wonderful sensation of cold drool underneath the tape!

Cheers
Gary

It seems your leaks are still too high. You should have under .40 for 95%.
I think if you give yourself a while to adjust you may stop drooling so much. I know I drooled when I first started taping but it stoped after a week or two.

Everytime you change something you need to give it a week or two. Every change can throw you off until your body adjusts to it.

Brenda

bdp522 wrote:It seems your leaks are still too high. You should have under .40 for 95%.

Brenda, I just took another look at what "95th Percentile" means in the software and it says "The value exceeded during the selected period for 5% of the time." Isn't the median value the most important stat? i.e. my median last night was 0.0. I'd have thought that was excellent so am I incorrect in my understanding of this?

My understanding is that 95% means that you spent 95% of the time at that pressure or lower. To me this means that most of the time you had no leaks, but for some of the time you had leaks big enough to compromise treatment causing you to have events that raised your AHI. I believe that once you get your leaks controlled(I like mine to be a straight line on the graph and in the range for the mask I use), THEN you look to changing pressures.
I would work on the leaks and once they are fixed I would give it a week before changing pressures.

Brenda

Ok, I must be having some real issues then as I just can't see how I can possibly get a better and more consistent mask seal to reduce my total leak rate to a 95th percentile of 0.4L per min. I called CPAP Australia today (the company I bought my CPAP equipment from) and they told me that the ResScan software doesn't compensate for mask rated-leakage i.e. the graphs display actual leakage and not compensated leakage (only the leakage that exceeds a mask's acceptable leak rate.) I was also told that the AutoScan software and ResScan software both used different measuring systems and that the information I was obtaining on forums must be based on users familiar with the AutoScan software and not ResScan.

So I'm not too sure who to listen to now as the consultant I spoke to said that my 95th percentile leak results of 2.4L per min were actually extremely good.....far, far lower than an absolute "acceptable" ceiling top limit of 25L per min (which does happen to correspond with a fixed red line at 25L per min that appears on all of the leak graphs).

But, there are still a LOT of events happening every night with an AHI last night of 27.7 so I guess I'll just have to persevere and see how it goes. Anyone familiar with ResScan 3.3 who can confirm or refute the claims made above by the CPAP Australia rep? I'm very confused now.......

_________________

CPAPopedia Keywords Contained In This Post (Click For Definition): CPAP, AHI, seal

I thought the leaks were reported in leak per second. If in fact they are leak per minute...the leaks are fine. I too would like someone with more experience to clarify if possible.

Brenda

I haven't seen any of the "Old Timers" comment here yet. BUT it seems to me you are in way too much of a hurry to see results. I am definitely no expert but it seems to take everyone some time to adjust depending on how long they have had OSA. It may take weeks or months before you body adjusts.

After a sleep study you would be best if you used a CPAP or CPAP mode set at triated pressure until you body adjusts then try to make improvements. I was issued a straight CPAP and felt good for about a year. I never knew what my stats were I just knew I was much better. After 15 months and some discust with my DME I purchsed a ResMed S8 Vantage which I use with an Activa Mask. I have had best results (at least number wise) on AUTO.

So at first don't worry about the numbers, give your body time to rest up before you try to control the numbers. Best of luck to you in your treatment.

bdp522 wrote:I thought the leaks were reported in leak per second. If in fact they are leak per minute...the leaks are fine. I too would like someone with more experience to clarify if possible.

The leak graph in ResScan is definitely L per min, but from memory I think the LCD on the machine itself is L per sec.....and I've been using the graph rate of L per min with any info that I've posted.

RestlessRoper, you're probably right - I'm just impatient and want to feel better NOW I've got a friend who's been using CPAP for years and he told me that he woke up from his very first night using it feeling unbelievably refreshed etc, and he's been like that ever since. I guess I've been so desperate to feel better that perhaps I'm a little unrealistic in my expectations......I just thought that surely I'd be feeling a little better after 2 weeks. I'll go back to the prescribed titration of 13cm CPAP and see how it goes for awhile.

Thanks for all the advice guys, it's appreciated.

Gary