[CPAP] Need Help w/Understanding Finding of My Sleep Study

[anakranism]

hi everyone.  i've had a long and mostly not great experience with sleep apnea treatment and my cpap machine.  my first sleep study was a joke.  i only slept for about 45 minutes and based on that they diagnosed me.  needless to say, as i became more comfortable sleeping with all of the gear on my face, my real sleep apnea issues became evident.  it took months to get them to increase the air pressure on my machine.  things got better, but, frankly, i rarely feel rested when i wake up.  

anyway, that's all a long story for another day.  now, 5 years later i just had a second sleep study and i actually fell asleep and slept through the night.  they supposedly got some good data on treating my sleep apnea, but i really don't understand what they're recommending.  the study states "The most appropriate setting of CPAP was 10 cm H2O.  At this setting, the sleep efficiency was 95.3% and the patient was supine for 30%.  The AHI was 0 events per hour(with 0 central events). Oxygen nadir was 93%."

what does "10 cm H2O mean"?  what does that translate into for a pressure setting?  i'm hoping someone out there can help...thanks, jim

[sheepless]

your resmed airsense 10 autoset has 3 settings related to pressure, all expressed in terms of centimeters of water. for brevity I prefer cmw. the machine pressure ranges from 4 cmw to 20 cmw. it can auto-range between a set minimum and maximum (apap) or it can be set to a single static cpap pressure either by switching from auto to cpap mode or by setting min and max to the same value. settings can be changed in the clinician menu. check out the black banner at the top of this page. you can get a cpap setup manual to learn more. also take a look at OSCAR. you'll need it to gather data the machine generates, post it here and folks will help you fine tune your settings.

edit: I forgot the 3rd setting which is exhale pressure relief or epr. setting a higher epr can make it easier to breathe out against a higher inhale pressure.

[Crimson Nape]

Hi anakranism - Welcome to the Apnea Board.

The 10cm H2O is a pressure measurement.  The pressure of the CPAP is measured with a Manometer.  While there are now digital ones, the primitive one was a "U" shaped device filled with water. Your 10 cm H2O would mean the pressure will press down the water by 5cm on one side and 5cm up on the other.. for a total of 10 cm.


I hope this helps.

[Dormeo]

There are useful links in Crimson Nape’s signature block. It’d help the experts help you if you would download Oscar, arrange your Daily chart per instructions, and then post your data.

It sounds as though your apnea is, or can be, well treated, yet you remain unrested. Your charts may give some good clues as to why that is so.

[anakranism]

thank you all for your help.  right now, my cpap machine is set to "auto set" and the max pressure setting is 17.8.  the minimum pressure is set to 12.8.  the EPR is set to off.  i've tried using the sleepy head software in the past and couldn't get the data from my disk(the one in my cpap machine to transfer onto the software properly.  i will try again, but i'm probably going to need some coaching.  i've never heard of OSCAR and i'll have to research it to understand what it's for.

[anakranism]

i can't believe it worked this time.  i got my data to show up in the sleepy head software.  here's a screenshot.  should i be lowering my max pressure and min pressure?  please see attachment.

[DeepBreathing]

G'day Anakronism. Welcome to Apnea Board.

Looking at your overall statistics I think your pressures are OK for the moment, and you're getting pretty good results as far as the AHI goes. However you have persistent and significant leaks - once the leak goes over the "red line" of 24 L/min the machine has trouble maintaining pressure or diagnosing and treating events. I see you're using a nasal mask, and my guess that you may be leaking via your mouth. If you can post a recent daily chart, we might be able to tell how the leaks are occurring.

Please make sure the daily chart is formatted as per the instructions here: http://www.apneaboard.com/wiki/index.php...ganization

i've never heard of OSCAR and i'll have to research it to understand what it's for.

Think of Oscar as an updated SleepyHead. For reasons that are too complicated to go into here, SleepyHead is no longer being supported and Oscar is the new standard software. You can download Oscar here: OSCAR

[anakranism]

               
hi.  yes, i saw very clearly that the issue of leakage is big.  the main reason for leakage with my cpap is for years i've tried to minimize the strap marks that wind up deeply grooved into my cheeks every morning as a result of wearing this device.  i've recently discovered that putting some folded tissue paper between the straps and my skin helps to alleviate this problem, so that i've been strapping the mask more tightly.  last night i strapped it a bit more tightly still and the leakage time went down a great deal. 

i also changed my pressure settings to minP--10 and maxP--16.  i figure if the sleep study found that 10 stopped my apnea episodes, i can probably proceed with less pressure.  i have to say, last night was the best night's sleep i've had in a long time.  so, i think i might be onto something. 

i also turned the EPR on at a level of 3.  my rational being, i probably exhale at some point during the night and i should probably do something to aid that process.

here are the screenshots of my data for last night minus the very last one.  let me know if you need this one too...thanks, jim

[DeepBreathing]

Hi Jim

On the face of it that's a big improvement. However we'd be able to see more important data if you could format the screen as per the instructions: http://www.apneaboard.com/wiki/index.php...ganization That will show us the most important graphs plus the machine settings and statistics. Make sure the calendar and pie chart are turned off.

You have a few more central apneas than normal, which may or may not be significant. Increasing the EPR can sometimes also cause central apneas to rise - it becomes a trade-off between increased comfort and increased apnea.

[SarcasticDave94]

Touching on the issue of leaks and mask adjustments: if I've read what has been described correctly, it seems you're practicing "the more it leaks, the more I'll crank up the tightness" method. I've done this myself until I learned a different way.

Quite a number of things with this would be incorrect. Some to most masks work better if they're on just snug enough to not leak. Some will leak more if overtight. Overtight masks can cause pain and could reduce sleep and rest.

Check the mask for proper fit and that it's not damaged and needing replacement parts. It's possible this mask isn't a proper choice for you. Read the Mask Primer for some great info.