Archived SH Discussions [Q&A Thread from Sep-2011 thru May 2014]

[SuperSleeper]

I wish I knew more about the way the machine declares an OA - or why it chooses to give a pressure pulse when it does. (or doesn't)

When the machine detects that you've stopped breathing for 10 seconds, it scores an apnea. It sends a pressure pulse to determine if your airway is obstructed. OA (obstructed airway) or CA (clear airway).

[SuperSleeper]

Different things can affect it.. Check the leaks and snore graphs, pressure pulses (bright red dots) and other surrounding events for more clues. eg, you could pull the mask up for a few seconds, and it will skip the breath.. you could be rolling over, awake and concentrating hard, etc...

The clinical definition of an obstructive apnea, is major reduction in airflow (<10% of baseline) for at least 10 seconds, accompanied by an oxygen desaturation of 3 or 4%.

Hypopnea is similarly defined, with a reduction to <50% of baseline.

It's the oxygen desaturations that really matter, as this is what causes the damage made by OSA/CA. If your worried, invest in an oximeter if you haven't already.. I recommend the cheap Contec CMS50's.. (at least a D+, with a usb port), available from eBay and everywhere else.

SleepyHead has a few tricks to get the oximetry data to compare against CPAP.. My current favourite method is starting both CPAP and oximeter recording at the same time. Import the CPAP data first, and then when you import the oximeter, it will pick the starting time of the CPAP session. This is the most accurate sync method I've found..

Even when it's synced, the SpO2 (oxygen saturation %) is delayed by 15 seconds or so, as the blood at your fingertip represents what was at your heart back when that blood was pumping through. (The actual time of this delay depends on your blood pressure, size of arteries/veins, and the length of your arms)

[SuperSleeper]

It is fascinating being able to see how I am really breathing at night, and how the machine responds, and how I then respond or not. I can see when the machine sends 3 or 4 pulses before I breathe again........

I can also see freakish breathing patterns which the machine does not count into AHI. I have had weeks where my AHI is between 2 and 3 each night, but one day I feel like a train wreck, another I feel fine, so the machine AHI is not a really good indicator of the quality of my sleep.

I don't have an oximeter, but I do have a video camera, and I will be filming myself to see how much of a difference sleeping on my back or my side makes. A month or so ago, I was so wrecked I didn't put my mask on one night, and woke feeling refreshed...of course I have no data to analyse for that night........Ay Sleep Doc had me do a sleep study and said that I had AHI of about 3-5 on my side, but it goes sky high when I am on my back. My thought is to sleep on my side, and ditch the machine. Her idea is that I should sleep on my back with the machine. My body's idea is to toss and turn and switch from one to the other!

If sleeping on your side causes lots less events, then it's pretty obvious this is what you need to do.. There are some funky pillows you can get that help keep the mask in order and make it more comfortable sleeping in that position.

I sleep in a recliner to find a compromise between the two positions.. Sleeping horizontally on my back or side makes things much worse, and stirs up my g.o.r.d. something shocking. I found I'm moving around a lot less on the couch than on the bed.

Look out for clusters of lots of events together. Sometimes your AHI can be normal, but all the events were crammed into one or two areas, still leaving you feeling like a train-wreck in the morning. SleepyHead's AHI/hour graph can help pinpoint how bad these are.

Sometimes everything looks relatively normal and I still feel like crap..

My average AHI was 7.71 for the last month, so definitely not optimal treatment yet..

[SuperSleeper]

Sleeping on the couch is a god way to keep me on my side, as I am curled up to fit, and the back of the couch stops me rolling flat. Hubby would not be happy with me on the couch though.....

It's worth trying for a few days.. If it makes a difference to how you feel, he's gonna notice the improvement in your mood/energy levels.

I've now got my recliner in the bedroom next to the bed.. (I'm lucky enough have a fairly decent sized bedroom at the moment.)

My wife doesn't mind getting the whole bed to herself..

[SuperSleeper]

Taking the card out while the machine is running could very well corrupt the card if the machine was writing data to the card.

You definitely should power off the machine before removing the card. It's probably a good idea to wait 10 or 15 seconds before taking the card out because the machine may write data for a short period of time after you turn it off.

The machine will probably have remembered your settings, along with much of the data, but you will probably have lost your detailed data from the machine.

One other possibility is that there's a virus on your PC and it messed up your card. Some people have had this problem before.

[SuperSleeper]

Thanks, JediMark, for creating the software. I've had my CPAP for one week and there is a lot to learn.

Under the Events tab there's a listing for "pressure pulse." I checked Google and believe it is when the cpap is determining if my airway is open or not. Is this correct? Also is it better to have a lower number for the pressure pulse or doesn't it matter?

You are correct on the meaning of pressure pulse.

I don't see any reason to pay attention to pressure pulses in general. They'll probably go up and down with the number of apneas you have.

[SuperSleeper]

I am on version V0.8.8 of Sleephead. Will the option "Check for updates" keep me current, or at some point will I have to delete the program and download a newer version. (Using Windows 7)
Thanks,
jerry

0.9 Beta onwards has an auto-upgrader.. The check for updates feature in 0.8.x just looks if a new versions available.

Not released yet, as I'm trying to finish of support for VPAP/ST / ASV machines, and improve the Intellipap support.

0.9 will have an actual installer.

[SuperSleeper]

I started using CPAP about 7 weeks ago. My only complaint about my (commercial link removed per rules) machine is it uses Auto-IQ (does a small pressure test every 30 operating hours) and I haven't been able to see what pressure it says is most effective. I've made a few trial/error adjustments over the last month with limited success (original settings were Auto IQ 6-11cm H2O with standard pressure of 8cm H2O).

Today, I have downloaded SleepyHead and have had an interesting time pouring over the SD card data. However, I haven't been able to determine what the Auto-IQ 'tests' are saying. Does SH have this data? Where do I find it?

Thanks

I haven't actually seen any Auto-IQ data yet, so I'm not really sure of the differences data-wise.

All I know is it pretends to be an APAP for thirty days, than barfs back to a "boring" CPAP.

I personally find this marketing concept of PR's offensive...

[SuperSleeper]

I haven't actually seen any Auto-IQ data yet, so I'm not really sure of the differences data-wise.

All I know is it pretends to be an APAP for thirty days, than barfs back to a "boring" CPAP.

I personally find this marketing concept of PR's offensive...

While I despise the 30 day nonsense (Shame on you Respironics!), it actually does something useful afterwards. It has sort of a "slow APAP" mode where it adjusts your static CPAP pressure every x days.

I'm a little more peeved than normal with Philips Respironics for this one, because It's kinda like a constant insulting reminder to people they've been sold a "lower capability" machine.. It's only slightly less useless than a brick. The sole purpose of this machine is to make people wish they bought an auto right after they have already been sold this abomination.

It annoys me more than the bricks, because this is obviously the same hardware platform.. Why can't they sell firmware upgrades to avoid the landfill waste!? Evil!

[curse]
I hope the clown from PR who thought up this evil invention gets fired.. preferably at high velocity into the sun, so they can't replicate this kind of mistake ever again. May he or she (along with the entire boardroom who approved these vile creations) develop the severest case of haemorrhoids. (providing their heads aren't already occupying space in that particular orifice)
[/curse]

This is one thing I respect about DeVilbiss.. they don't have useless piece of junk brick machines clogging their current catalogue.
Though I'd be a lot more impressed with them if they bothered to add the Flow Waveform data, and logged prescription/settings changes properly :-/

[SuperSleeper]

It annoys me more than the bricks, because this is obviously the same hardware platform.. Why can't they sell firmware upgrades to avoid the landfill waste!? Evil!

[curse]
I hope the clown from PR who thought up this evil invention gets fired.. preferably at high velocity into the sun, so they can't replicate this kind of mistake ever again. May he or she (along with the entire boardroom who approved these vile creations) develop the severest case of haemorrhoids. (providing their heads aren't already occupying space in that particular orifice)

As far as I can tell, if they hadn't put that never-to-be-sufficiently-damned 30 day auto with copy protection BS into the machine, it would actually be a useful improvement to the PRS1 Pro machine. It might get some doctors with their head stuck in the wrong place to put their patient on the "adjust every 30 hours" auto check mode.

At least the autocheck mode doesn't start you out with a sub-therapeutic pressure every night like you get with a wide-open 4-20 pressure range.

I'd like to see the "autocheck" function added as an option to the full time auto machine as long as they don't put the blasted 30 day copy protection into it.

I totally agree.. That would be a welcome improvement..

This is probably how CPAP should work for most people.. 1 day a month the machine does some investigation to make sure the Pressure choice is still right..

I still really wish Philips would offer firmware upgrades like DeVilbiss..

It's not like the PRS1 machines don't have an upgrade port hidden in or behind the SD card slot..

Maybe one day someone sufficiently frustrated and disgusted will figure out how to hack their cpap machines internals, and put an end to these crappy firmwares..

Or save themselves the trouble and just design new control circuitry using the fan ripped out of an old machine. (which is probably what I'd do if I wasn't so damn foggy)