15 AHI per hour with CPAP. Help me ...

Hello everybody,
I am a new user of cpap and I have some doubts. Could you help me?
First a summary:
- 29 years, 48 AIH per hour, the user approximately 40 days, S8 Elite 2 with humidifier and nasal mask comfortgel.

Looking at my results this month I had a mean AHI 15.5 / h, being 1.1 and 14.1 AI HI. Use the drug Stilnox to induce my sleep and an anti-allergic (loratadine) to alleviate allergic rhinitis. The pressure that I used initially was 8cm, and how to test this last week raised to 8.8 cm. But I had no decrease in my rates. Only two nights I could have 5 AIH / hour. And I have kept an average of 4 hours of CPAP use per night. For the mask shot without realizing it, so I have awakened at dawn to check.

Therefore, I have some questions:
- This index AHI presented can be considered good?
- It tends to decrease with time?
- What other strategies could try to lower the rate?

Thank you in advance for your attention by all.

Gus

Hi,

In general, your AHI needs to be under 5 to be considered to have effective therapy. Many people find that any level of events disturbs their sleep, so many folks strive for as low of AHI as possible. At 40 days, you are probably well past the point where any more time will lower your AHI.

The AHI numbers that are on the machine could be a one night number, or it could be an average. You need to read your manual and see what kind of number you have. If it is an average, you will want to reset it every day so you get the number from the previous night. You can have a really good night, and the average will hardly move. That doesn't give you any useful information.

How do you feel? What do you feel like when you wake up?

The biggest issues that new users have are mask fit and leaks. That is what folks here would suggest looking into first.

A follow-up question is how was a pressure level of 8 arrived at? What was the number that was found in your sleep study, and what was your AHI on CPAP in your study?

Finally, did your study report any positional issues? For example, some folks have far, far worse problems when they are on their back. You can tell this pretty quickly by sleeping on your side for a few nights, and see if your AHI goes down.

-john-

Hi Gus,

Gusbr wrote:S8 Elite 2

Gusbr wrote:Looking at my results this month I had a mean AHI 15.5 / h, being 1.1 and 14.1 AI HI.

Those two things jumped out at me in your post, Gus.

I don't know this for a fact, and I'm not a doctor or anything in the health care field, but it's my personal opinion that when a person is using a ResMed S8 machine, the "HI" (hypopnea index) is generally going to be higher than with other brands of machines (and higher than with the newer ResMed S9 models.)

That doesn't mean a ResMed S8 is not treating a person effectively.

I don't pay much attention at all to the overall AHI or the HI numbers when I use a ResMed S8 machine. I look only at the AI number (the "apnea index" number.) If the AI is nice and low (which yours is, with that AI of only 1.1 ) I think the treatment is going extremely well.

If I do bother to look at the overall AHI using a ResMed S8, and if the AHI is over 5, I immediately look at the separate AI and HI numbers. If the AI (apnea index) is low and the HI (hypopnea index) is high, I mentally cut the "HI" number in half and add that "halved HI " number to the AI...to give me a new overall AHI....a lower AHI.

Doing that "HI-halving" gives me (I think... again, it's just my opinion) a more realistic comparison if I'm going to compare my S8 results against the results of other brands that use a more lenient definition of "hypopnea." And it's a more realistic comparison (imho) if I'm going to compare the S8 results against a "good CPAP treatment is an AHI under 5 " standard.

In other words, a degree of "flow limitation" that a Respironics machine would call "flow limitation" and not lable as a "hypopnea" could be something a ResMed S8 machine would lable "hypopnea." It's just a matter of each manufacturer having a different definition of "hypopnea" and building their own definitions into their machines. Each manufacturer picks its own arbitrary line in the sand for saying, "this much flow limitation is still just 'flow limitation', and that much flow limitation is 'hypopnea' . "

So, the "HI" (hypopnea index) results from different brands could be quite different. Doesn't mean one manufacture is right and another is wrong. Doesn't mean one is "missing" things that the other is catching. Doesn't mean one is "over-reporting" or another is "under-reporting." Doesn't mean one treats better than another.

Just means they are using different definitions.

None of the manufacturers use the same definition for "hypopnea" that sleep labs use when scoring PSG (polysomnogram) sleep studies. None of the machines are checking drops in oxygen level or checking arousal signals sent by the brain to make a person breathe better during sleep. Both those are things sleep labs use in defining an event as a "hypopnea" instead of just a flow limitation. So...I'd not get very concerned at all about a high AHI reported by a CPAP machine at home (especially by a ResMed S8 or S7 machine) if that high AHI was made up mostly of "hypopneas."

If I were using a nasal mask, as you are, I'd check the leak rate each morning, in the LCD on the machine, to see if excessive leaks were compromising the therapy. I'd want to see a leak rate that was as close to zero as possible when using a ResMed machine. If I saw a leak rate that was close to .40 L/s (liters per second) with a ResMed S8 machine, I'd start trying to figure out if it was mask leaks or mouth air leaks that was driving the leak rate up.

Good luck, Gus. Keep posting and let us know how it goes for you!

Up the pressure. 8.8 is pretty low. You need more. Try 12.

Don't listen to "guests" who don't know what they are talking about.

Don't make radical changes on a whim. Make changes gradually while observing the data. (If your change from 8.0 to 8.8 made no discernible improvement, there's no motivation to raise it higher.)

I don't know anything at all about the S8, but I personally wouldn't just outright ignore the hypopnea data. During my sleep study my AI was only 3.4, but my HI was 67.3.. which combined was leading to over 80 awakenings+arousals per hour over night, and was greatly impairing my sleep. If only the AI data was looked at, one would think that I was doing great.

Hello guys, thanks for the responses.
Last night, shortly after writing this post, I researched the cpaptalk on changes in pressure and decided to do a test. Increased the pressure from 8.8 to 10 with ramp 45 minutes, starting with the pressure 7. Incredibly the numbers that night were full AHI = 6.2, while only 0.5 of AI and the rest of HI in 4 hours with the appliance.
I check every day the amount of leakage in the month and the average was only 0.02, since I use a tape to seal the mouth and I adapted well to the mask.
I will continue with these parameters for a week to see results and I will write my results to you.
This morning I woke before the alarm sounds, and I feel much more prepared and relaxed than on previous nights.
I woke up with a little more gas in the stomach, but nothing that bothers me, waking up in a good mood after so many years worth the effort.
Anyway, today I woke up much more enthusiastic about the treatment, but now believe he is walking back to a normal life.
But I have another question for you then maybe Stilnox can cause relaxation of the pharyngeal muscles?

Again thanks for the comments. You make me feel supported.

Regards,

Gus

Telle wrote:I don't know anything at all about the S8, but I personally wouldn't just outright ignore the hypopnea data. During my sleep study my AI was only 3.4, but my HI was 67.3.. which combined was leading to over 80 awakenings+arousals per hour over night, and was greatly impairing my sleep. If only the AI data was looked at, one would think that I was doing great.

Telle, I agree absolutely with you that a person should not ignore hypopnea data from a sleep study. I was talking about hypopnea data from our treatment machines...not the hypopnea data from sleep studies.

Hypopnea data from a PSG sleep study is quite different from "hypopnea" data from the treatment machines we use at home.

The definition(s) for "hypopnea" used to score PSG sleep studies takes into account air flow and drops in O2 and arousals.

The definition(s) for "hypopnea" used by CPAP/Autopap/bilevel machines at home look at air flow, but do not take into account O2 or arousals. Our machines can't even see those last two things. And...different CPAP manufacturers use different definitions from each other as to what constitutes a hypopnea.

ResMed changed its definition of "hypopnea" when it designed the S9 model. With the older S8 model, I'd either pretty much disregard the hypopnea data from the S8, or I'd mentally cut the S8's hypopnea result in half. But that's just the way I look at it, and I'm not a doctor.

Hello, updating the data, have again had a low apnea index, in total only eight, but I slept only two hours with the appliance. I do this q with these indices is controlled to stop using the drug, which makes me sleep very heavy and will not let me see when I take the mask in the middle of the night. Can you give me any tips on that?

Do you have the software and card reader to be able to upload your data to your PC?

You need a Windows PC and a ResMed data card reader, plus the ResScan software.

If you want to use it, we can help you get the software.

jdm2857 wrote:You need a Windows PC and a ResMed data card reader, plus the ResScan software.

Hi,

The software works on any intel based Mac running OS/X. All you need is Parallels or VMware Fusion, and you can run it in a virtual machine window. I do both ResScan and Encore Viewer this way.

-john-