Zero AHI stuck on 60 series CPAP

[SleepyCPAP]

My new PRS1 460 CPAP (firmware 3.02) has had two full nights and a couple nap test runs before that, but is showing "0" for AHI, Periodic Breathing, etc. I know it is counting nights of compliance properly (it shows "2") and the number of hours run. When I load the data into Sleepyhead I can see my real AHI, so the machine is recording to the card properly. Yes, it is set to display the data, I've checked the clinician's menu. Why is the screen stuck on zero (1 night, 7 day, and month all show zero)?

I'll unplug the machine, and then plug it back in (I saw that works for S9 units). But is there something else I should do to get it unstuck?

-- SleepyCPAP

[tetragon]

What AHI shows in SleepyHead? I have a PRS1 560, and it displays the AHI as 0.0 if it is below 1.0.

[sol]

are you checking after noon
after noon, start a new CPAP day and data reset to "0"

[squid13]

The PRS1 uses Greenwich Mean Time to reset it to zero. ResMed resets at noon your time if you have your time set right in the machine.

[Pugsy]

Actually the PR S1 machine doesn't reset to zero like the ResMed machine does.
It does use GMT time...and on the machine LCD screen the AHI isn't updated until Noon GMT time. So it depends on where you live in relation to GMT time and what time you are checking the LCD screen.
So to see any changes on the LCD screen a person has to wait until after 12 Noon GMT time.

What is the AHI on the software reports?
If it is real low the machine may be doing the average and rounding down to 0.0.

So the 1 day AHI...you need to check it after 12 noon GMT time if you expect to see changes.
Any changes to the 7/30 day averages also won't show up until after 12 noon GMT time.
The SD card will have the results prior to the GMT time thing.

If your AHI on the software report is significantly higher and obviously not 0.0....there's a problem.

[JohnO]

What is your AHI when you look at software? My AHI is always below 1.0, so the LCD display always shows 0.


John

[sol]

Check "Show AHI/leak/PB" set to ON
If set to OFF no data is displayed on the machine or the software

[SleepyCPAP]

Thanks all for your input.

The first night Sleepyhead showed .64 as my AHI. I looked at the breath patterns and agree.

What I'm hearing is that these new machines don't do AHI like the older PRS1 machines. When I reset my 450 machine each night it shows the overnight results (in the week and month display) after noon GMT rounded to the first decimal place. So based on that I was expecting to see .6 on the screen of the 460 machine for that first night in the 1-day listing. Instead I'm hearing anything under 1 gets rounded down to zero????

The most recent nights Sleepyhead and the machine agree -- I've been lucky enough to experience real "0" AHI nights. So is it still stuck, or just reporting accurately? We'll see when I get another non-zero night.

I've been at this since 2010 and have got my therapy fine-tuned and pillow and sleep routine figured out pretty well and so I do get down to zero sometimes, and rarely hit 1. Average has been around .3 AHI, and RERA and flow restriction is something I should look at more. It is a big difference for me when I have .6, so I look at leaks or other details when I see that. I realize I'm one of the lucky ones on this forum, in that straight CPAP really did make a difference for my AHI once I "got the hang of it."

-- SleepyCPAP