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

APAP and SH disagree on AHI
#1

My routine is to wake up, press the button on my APAP to get a general reading, then a bit later pull everything into Sleepyhead. Been doing that a long time. Never have the numbers disagreed.

Today my APAP gave an AHI reading of 1.6, while SH says 2.35. I do not include the "test" events in the total. I did not cross the "12 PM" boundary.

What's up with that? Anyone experience anything like this?
Post Reply Post Reply
#2
I never cared much about the LCD screen readouts on my PRS1, but compare my SH scores with my EncoreBasic scores. They have been aligned each time I checked. My LCD screen has totally diff numbers, sometimes higher sometimes lower.
Dedicated to QALity sleep.
You'll note I am listed as an Advisory Member. I am honored to be listed as such. See the fine print - Advisory Members as a group provide advice and suggestions to Apnea Board administrators and staff concerning Apnea Board operation and administrative policies. Membership in the Advisory Member group should not be understood as in any way implying medical expertise or qualification for advising Sleep Apnea patients concerning their treatment.
Post Reply Post Reply
#3
Try ResScan and compare with SH.
Has to be some other form of respiratory arousal that SH is counting in the total.

My LCD is always right on with reporting SW.
This Veteran is medicated for your protection.
Post Reply Post Reply


#4
(01-08-2015, 05:17 PM)justMongo Wrote: Try ResScan and compare with SH.
Has to be some other form of respiratory arousal that SH is counting in the total.

My LCD is always right on with reporting SW.

Well, if the Autoset and SH are counting different types of events, then it would have to have been a coincidence every night for 6 months in a row that the numbers still added up to the same total; astronomically impossible.

If SH is counting anything other than the common three types of events in AHI (and it is not counting the experimental events as that is turned off in the prefs), it sure is doing it opaquely.

But then some of this stuff may be obvious, yet still opaque to me. I am still not sure what triggers certain pressure changes in my APAP; the SH graphs don't seem to reveal anything that connects.
Post Reply Post Reply
#5
OK, it happened again. Again the Autoset gave the lower reading (1.8) while SH gave the higher reading (2.88). If I do the math, SH is correct according to the number of events it flagged, for AHI as well as for the three individual indexes.

The Autoset is also reporting that I slept (or ran the blower) for 24.0 hours. Nuh-uh, that didn't happen. And if it had, that would mean that its calculated AHI, if accurate to the flagged events over time, would be more like 0.7. So, wrong on both counts.

So something funny is going on here.
Post Reply Post Reply
#6
(01-10-2015, 12:46 PM)TyroneShoes Wrote: OK, it happened again. Again the Autoset gave the lower reading (1.8) while SH gave the higher reading (2.88). If I do the math, SH is correct according to the number of events it flagged, for AHI as well as for the three individual indexes.

The Autoset is also reporting that I slept (or ran the blower) for 24.0 hours. Nuh-uh, that didn't happen. And if it had, that would mean that its calculated AHI, if accurate to the flagged events over time, would be more like 0.7. So, wrong on both counts.

So something funny is going on here.

The time period (number of days included in the summary statistics sleep report) is adjustable.

So perhaps settings for the number of days are different between the machine versus SH?

Membership in the Advisory Member group should not be understood as in any way implying medical expertise or qualification for advising Sleep Apnea patients concerning their treatment. The Advisory Member group provides advice and suggestions to Apnea Board administrators and staff on matters concerning Apnea Board operation and administrative policies - not on matters concerning treatment for Sleep Apnea. I think it is now too late to change the name of the group but I think Voting Member group would perhaps have been a more descriptive name for the group.
Post Reply Post Reply


#7
(01-10-2015, 12:46 PM)TyroneShoes Wrote: OK, it happened again. Again the Autoset gave the lower reading (1.8) while SH gave the higher reading (2.88). If I do the math, SH is correct according to the number of events it flagged, for AHI as well as for the three individual indexes.

The Autoset is also reporting that I slept (or ran the blower) for 24.0 hours. Nuh-uh, that didn't happen. And if it had, that would mean that its calculated AHI, if accurate to the flagged events over time, would be more like 0.7. So, wrong on both counts.

So something funny is going on here.

I'm not laughing.

I think you are looking at the LCD screen that says "Sleep Report."
It can be set for 1 day or 7 days or 30 days... That's not the one to look at.
It's normally set to 30 days... I am guessing it's set to 1 day.

The report screen you want is called "Sleep Quality." (Has the smiley face, says "last night" -- has number of hours "usage" and the AHI for that period.

How about you pull out your digital camera, put it in macro mode; and shoot a photo of the screen you're looking at.
And, post it.
This Veteran is medicated for your protection.
Post Reply Post Reply
#8
"Sleep Quality" is what I always have been looking at; one button press on the Autoset, includes smiley for mask fit. I am only looking at one day at a time in SH as well.

So I rebooted the damned thing. Unpowered it for an hour. Today the numbers matched. Makes sense; I have yet to see anything using a microprocessor that didn't need a swift kick in the pants now and then. I once left my old PowerPC-based MacBook up for something like 187 days and it still worked perfectly, but then I needed to upgrade the SW, so that is the record so far.
Post Reply Post Reply
#9
(01-11-2015, 01:06 PM)TyroneShoes Wrote: So I rebooted the damned thing. Unpowered it for an hour. Today the numbers matched. Makes sense; I have yet to see anything using a microprocessor that didn't need a swift kick in the pants now and then

Same here. I have to reboot my router every so often. I have a friend who never shutdown his Windows based computer -- just let it sleep at night. Eventually a bit error will creep into any system. He'd call and say, "My mouse pointer won't move." And, I would tell him to "hold the power button on for 4 seconds."

We're getting to the point in microelectronics where a bit state is represented by a charge of the order of 100 electrons. A cosmic ray can create that many electron-hole pairs in a bit volume.

Actually, cosmic ray induced upsets have been a design factor in space environments since about 1975 when Binder, Smith and Holman published their paper. IEEE TNS Vol. 22, #6
This Veteran is medicated for your protection.
Post Reply Post Reply


#10
(01-11-2015, 01:06 PM)TyroneShoes Wrote: So I rebooted the damned thing. Unpowered it for an hour. Today the numbers matched. Makes sense; I have yet to see anything using a microprocessor that didn't need a swift kick in the pants now and then. I once left my old PowerPC-based MacBook up for something like 187 days and it still worked perfectly, but then I needed to upgrade the SW, so that is the record so far.

It would seem that the S9 has some undocumented features(bugs). I had to do a total power down to get the Climateline to work in the auto mode after I had it in the manual mode and reset it back to auto.

On a side note: I have a computer running phone attendant software in DOS at a client site that was started in 1997 and hasn't gone down yet. . . Now that I said this, it's probably the kiss of death for it.
______________________
Useful Links -or- When All Else Fails:
Posting SleepyHead Charts in 5 Easy Steps
Robysue's Beginner's Guide to Sleepyhead
Apnea Helpful Tips
Post Reply Post Reply


Possibly Related Threads...
Thread Author Replies Views Last Post
  Travel apap machines yankees123 2 72 Yesterday, 07:15 PM
Last Post: OMyMyOHellYes
  Still snoring with APAP Tahera11979 31 1,240 06-23-2017, 09:38 AM
Last Post: Tahera11979
Question Should I use APAP while waiting for ASV Shift Worker 5 221 06-14-2017, 08:11 PM
Last Post: Sleeprider
Thumbsdown Use APAP to approx. current AHI. Mogy 1 145 06-09-2017, 11:05 PM
Last Post: chill
  Weinmann / Löwenstein Prisma 20A Auto CPAP: APAP settings: standard vs. dynamic Costas P 0 116 06-08-2017, 06:35 PM
Last Post: Costas P
  Bench evaluation of 10 APAP / CPAP machines Costas P 7 456 06-08-2017, 07:42 AM
Last Post: Timur
  Apap to CPAP for camping, settings question. DavePaulson 20 707 06-04-2017, 08:19 AM
Last Post: DavePaulson

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.