AHI Incident

[Sheriff Buford]

I ordered a Resmed S9 Autoset yesterday from my new DME (who was knowlegable about sleep apnea - so refreshing!). I have bad shoulders, so I turn alot during sleep (I flip more that a pancake!). I normally hold my breath while turning. At best, my breathing is interrupted. Will these incidences be recorded as an AHI incident?

Sheriff

[KatieW]

My guess is that if it's under 10 seconds and meets the ResMed definition of hypopnea, it could register as that. Or, if over 10 seconds, it would be a central apneas, since there is no airflow--but no obstruction.

Let us know what happens after a few nights.

[70sSanO]

I can only speak of my personal opinion, but I am less enamoured with AHI numbers than I am with the obstructive numbers. My goal has been to get my obstructive numbers down as low as possible and in doing so my HI numbers have also been decreasing.

I have been increasing my pressure and the fall out of this has been an increase in my central events.

The nice thing about the detailed data is that you can see not just the type and when the apneas occur but also the duration. Over the past few weeks the increased pressure has improved both of these areas. At lower pressures I actually had 40-50 second obstructions with therapy.

If I compare a AHI of 4.2 from 3 weeks ago to 4.2 today. I find I have dropped from over 2 obstrucitves to less than .5 but my centrals have gone from less than 1.5 to over 3. Almost all my centrals are 10-15 seconds, if they were areound 30 seconds I'd be more concerned.

I suspect that an Autoset will provide the best of both worlds and may bring the centrals down faster.

Thankfully I'm not losing sleep over the number either mentally or literally.

John

[avi123]

I agree with KatieW. But notice that the Centrals don't go into AHI calculations. Overall, body movement, taking off and putting on the mask, pinching the air hose, etc., could be assumed by the CPAP to be an event. To prevent it you need to become a Mummy. That's way taking averages over months make sense.

[Sheriff Buford]

John (70sSanO): do you get the information you referred to from the display screen, or did you have to buy the software to get that info? Sheriff

[Lizistired]

Buford, The link to the ResScan software is in Uncle Bob's signature block. If you get that you will be able to see the actual events. I toss alot too, and find that I take a few deep breaths before many of my "events" which I assume are turning over. In those cases my O2 doesn't drop so I don't worry about them.

[avi123]

[quote="Sheriff Buford"]John (70sSanO): do you get the information you referred to from the display screen, or did you have to buy the software to get that info? Sheriff[/quote

Shariff, your S8 Escape II machine is one of dumbest CPAP on the market. Beside compliance it has no output of medical data. Try to get it changed to S9 Autoset or S9 Elite. Then you could read the medical indexes on the machines screens or download it by using a ResScan software #3.10 and up, available free in this forum (probably pirated!). Then you could stick a regular SD Card (similar to those used in digital cameras, costing $10 +/- each) and next plug it into the CPAP. The next day plug the card into your laptop by using a $10 USB adapter, and read all your graphs.

[70sSanO]

John (70sSanO): do you get the information you referred to from the display screen, or did you have to buy the software to get that info? Sheriff

I use Resscan 3.14 that you can download. Uncle Bob has a link in his signature. You just download the data from the SD card that is in the back of the machine. Make sure you select all detailed data. The software shows the detail when things happen and for how long and other stuff.

The machine screen will give you the AHI, AI and CA numbers. I believe that if you subtract the AI number from the AHI number you get the HI. And if you subtract the CA number from the AI number you get the obstructions.

I've been on CPAP quite a while but I'm new to the data stuff. I'm sure that others can provide a better explanation.

John

[Lizistired]

Ooops, sorry, I didn't see the Escape in your sig.

[NightMonkey]

Shariff, your S8 Escape II machine is one of dumbest CPAP on the market. Beside compliance it has no output of medical data. Try to get it changed to S9 Autoset or S9 Elite.

avi, At least read the OP. Sheriff said he ordered the Autoset.

Then you could read the medical indexes on the machines screens or download it by using a ResScan software #3.10 and up, available free in this forum (probably pirated!).

What is wrong with you today?

- The software is not available "in this forum".
- The software is available free from ResMed (not "pirated").
- It is version 3.14

Sheriff, Good move to get an Autoset.

[robysue]

But notice that the Centrals don't go into AHI calculations.

This is just plain WRONG: On the Resmed S9's:

• AHI = AI + HI and AI = CAI + OAI + UAI

where

• CAI = (# clear airway or central apneas)/(time machine was running)
  OAI = (# obstructive apneas)/(time machine was running)
  UAI = (# "unknown" apneas)/(time machine was running)

and an apnea is labeled as "unknown" if the S9's algorithm cannot reliably determine whether the apnea was obstructive or central.

[avi123]

But notice that the Centrals don't go into AHI calculations.

This is just plain WRONG: On the Resmed S9's:

• AHI = AI + HI and AI = CAI + OAI + UAI

where

• CAI = (# clear airway or central apneas)/(time machine was running)
  OAI = (# obstructive apneas)/(time machine was running)
  UAI = (# "unknown" apneas)/(time machine was running)

and an apnea is labeled as "unknown" if the S9's algorithm cannot reliably determine whether the apnea was obstructive or central.

Sorry, I must have slept too long this morning.

But, I got a question which might interest the Sheriff:

A couple of days ago I got these results on my S9:


Statistics

Serial No.: 23101067352
Product: S9 Elite
4/17/2011 - 4/17/2011

Device Settings
Therapy Mode: CPAP Set Pressure: 9.0 cmH2O EPR: Off
EPR Level: 2.0 cmH2O

Leak - L/min
Median: 0.0 95th Percentile: 12.0 Maximum: 60.0


AHI & AI - Events/hr

Apnea index: 12.1
AHI: 20.3
Obstructive: 6.6
Central: 4.6
Unknown: 0.9
Hypopnea index: 8.2

My question: why I with an AHI of 20.3 I don't feel as crappy as robysue does with an AHI of 3.9 (judging by her posts ?

Another question: why a couple of days before the above I got these results:


Statistics

Serial No.: 23101067352
Product: S9 Elite
4/11/2011 - 4/11/2011

Device Settings

Therapy Mode: CPAP Set Pressure: 7.4 cmH2O EPR: Off
EPR Level: 2.0 cmH2O

Leak - L/min
Median: 0.0 95th Percentile: 10.8 Maximum: 36.0

AHI & AI - Events/hr:
Apnea index: 3.7
AHI: 5.9
Obstructive: 1.2
Central: 2.3
Unknown: 0.1
Hypopnea index: 2.2

You might say: it's the lower pressure!

OK, but look here, a few days before with same pressure:

Statistics

Serial No.: 23101067352
Product: S9 Elite
4/2/2011 - 4/2/2011

Device Settings

Therapy Mode: CPAP Set Pressure: 7.4 cmH2O EPR: Off
EPR Level: 2.0 cmH2O
Leak - L/min
Median: 2.4 95th Percentile: 22.8 Maximum: 27.6

AHI & AI - Events/hr
Apnea index: 10.0
AHI: 12.7
Obstructive: 4.7
Central: 5.1
Unknown: 0.1
Hypopnea index: 2.7

I have been titrating myself for 3 months and NO trend has been showing up!

Overall, my Epworth Sleepiness Scale is the same, regardless of the AHIs.

Any opinions?

[Pugsy]

I am biting my finger tips off to keep my mouth shut. Also looking for a 2 X 4....
avi123 won't listen to many anyway..

Sheriff Buford,
In theory it is possible that some of those tossing an turning holding of breath might show up on the on screen data if it meets criteria in some fashion. A pause in breathing is a pause in breathing and some of them are normal but the machine on knows to report on what it senses.

Get the software and then you can see if anything is there to warrant even worrying about. You have gone a long time without seeing your results. It may not even be exciting. I finally got a PR S1 APAP last week so that I could see the extra data. It's not all that different from my M series data except now I see a random CA. Not enough to worry about and I toss and turn a lot. It is kinda nice to satisfy my curiosity though.

When you get the Autoset get the software. If nothing else it satisfies the "what ifs"... you may have had.

[70sSanO]

Man, your numbers are really whacked out. I do know that if I am stressed and I don't sleep very well I can have great numbers. For me I worked on getting my bed pillows at the right height first and looked at the detail data.

I'm not a doctor and this may be totally wrong, but it seemed to me that a couple of 40-50 second obstructive apneas were probably a lot worse, health wise, than 8 or 9 ten second apneas... and I had 40-50 second apneas using my machine. So my primary goal was to get those times down, and hopefully the frequency because I was also have some of those 10 second varieties.

Now this may not work for you, but it sure seemed like if it takes 40 seconds to fix an apnea, I needed more pressure. So I increased my pressure and checked the details obstructive events and I've gone from a setting of 10.0 to 13.0 and the worst duraction has dropped to around the 20 second mark and I'm not getting as many of them either.

John

[avi123]

Man, your numbers are really whacked out. I do know that if I am stressed and I don't sleep very well I can have great numbers. For me I worked on getting my bed pillows at the right height first and looked at the detail data.

I'm not a doctor and this may be totally wrong, but it seemed to me that a couple of 40-50 second obstructive apneas were probably a lot worse, health wise, than 8 or 9 ten second apneas... and I had 40-50 second apneas using my machine. So my primary goal was to get those times down, and hopefully the frequency because I was also have some of those 10 second varieties.

Now this may not work for you, but it sure seemed like if it takes 40 seconds to fix an apnea, I needed more pressure. So I increased my pressure and checked the details obstructive events and I've gone from a setting of 10.0 to 13.0 and the worst duraction has dropped to around the 20 second mark and I'm not getting as many of them either.

John

John, since we have S9 Elite for CPAPs once we raise the pressure to above 10 cm it stays like that during all inspiration cycles. In the S9Autoset it could go to 13 cm if it detects an Obstructive but next it would drop to below 10 if we set it as such. I don't know about the damage of 13 cm going into a Central.

p.s. my prescribed pressure at the Sleep Study was 6 cm.